WESTERN SECTION IAEI

CODE PANEL QUESTIONS & ANSWERS 2014

1. An installation consists of a breaker–breaker 480v series rated system and a industrial controller. The line side breakers are 65k, the downstream panel contains 14k AIC breakers. The fault current at the downstream panel is 28,000. Next to the downstream panel attached by a close nipple is an industrial controller that was a field evaluated an issued a 14k sccr. The fault current is approximately 25,000 at the line terminals of the controller. Is this controller protected and NEC compliant since it has the same rating as the breakers in the panel? If not what is a solution?

2. Does a UPS require a disconnecting means ahead of it and within sight? Is the UPS considered an appliance for installation guidelines?

Reference 645.11, 700.12(C), 701.12(C) and the Definitions in 100

This is a difficult question to answer. Personally, I would say yes that you would need a disconnect before the UPS to isolate it from the power source. You would also need a disconnect between the UPS and the piece of electrical equipment that might need to be serviced.

However, I could not find a section within the code that made this statement generally. I did find the reference in 645.11 that require disconnects and in 700.12(C) and 701.12(C) states that the UPS needs to be treated as a Battery and Generator Set where 700.12(B)(6) 701.12(B)(5) for Outdoor Generators Sets require a disconnect. As NFPA always stated: We look forward to your Public Input.

Is an UPS consider an Appliance?

I would say maybe. If it is a cord and plug piece of equipment I would say yes and the disconnect could be accomplished by unplugging the UPS per 422.33. Otherwise the UPS is a piece of electrical equipment.

Article 100 defines the following:

Appliance. Utilization equipment, generally other than industrial, that is normally built in standardized sizes or types and is installed or connected as a unit to perform one or more functions such as clothes washing, air-conditioning, food mixing, deep frying, and so forth.

Uninterruptible Power Supply. A power supply used to provide alternating current power to a load for some period of time in the event of a power failure.

Informational Note: In addition, it may provide a more constant voltage and frequency supply to the load, reducing the effects of voltage and frequency variations.UPS systems do not alleviate the need for a generator or second utility service power source, but they do serve to buffer critical loads from the effects of generator starting time and voltage and frequency variations.

3. UL stands behind their reducing washers even when over 250v if they are installed by removing all rings in a concentric. If we have an installation that is 120v or208v and use a reducing washer in a disconnect but do not remove all the rings is it now required to install a bonding bushing?

Answer: NEC 250.96(A), 110.3(B), UL White Book, QCRV, Pg. 392

Yes, NEC 250.96 (A) requires the enclosure to be bonded and remove the paint from the effected area. See Outlet Bushings and Fittings (QCRV) in the UL White Book that states: GROUNDING

Metal reducing washers are considered suitable for grounding for use in circuits over and under 250 V and where installed in accordance with ANSI/NFPA 70, "National Electrical Code." Reducing washers are intended for use with metal enclosures having a minimum thickness of 0.053 in. for non-service conductors only. Reducing washers may be installed in enclosures provided with concentric or eccentric knockouts, only after all of the concentric and eccentric rings have been removed. However, those enclosures containing concentric and eccentric knockouts that have been certified for bonding purposes may be used with reducing washers without all knockouts being removed.

4. Under the 2014 NEC, do I now have to have a grounding electrode system for roof top solar arrays? Are ground rods required?

Answer: Yes. You did not ask, but I’ll answer anyway (Do I have to have an auxiliary grounding electrode system…Yes). Are ground rods required…No.

Code Reference: 690.47(A); 690.47(B); 690.47(C)(1), (2), or (3); 690.47(D)

An auxiliary grounding electrode system is required to be installed in accordance with 250.52 and 250.54 at all ground- and pole-mounted PV arrays and as close as practicable to roof-mounted PV arrays.

The large quantity of conductive material that is added to a roof when a PV system is installed increases the likelihood of a lightning strike. This PV grounding electrode system would help to minimize the effects of such a lightning strike. The purpose of this PV grounding electrode is two-fold. The primary purpose is to maintain the frames of the PV array to as close to local earth voltage potential as possible. This is favorable to relying on a potentially long equipment grounding conductor back to a grounding electrode perhaps on another structure. This situation presents a potential shock hazard and necessitates these PV arrays be grounded to a local grounding electrode. The secondary purpose of this PV grounding electrode is to provide a simple and direct path to earth for any static charge that may build up in storm or lightning activities.

The term “Auxiliary” was added to the title and reference in the text along with a reference to 250.54 to indicate that this PV grounding electrode system is not required to be tied into the premises grounding electrode system. This tie-in with auxiliary grounding electrodes will also make it clear that if multiple PV “auxiliary“ grounding electrodes are installed, they do not need to be bonded together by a dedicated bonding jumper. These grounding electrode(s) will be permitted to be connected to the equipment grounding conductors of the branch circuit(s) or feeder(s) to these PV arrays.

5. A 200- amp main breaker for a home is installed on the exterior of the house and from there a 4/0 aluminum SER cable rated at 75 degree is installed to the sub-panel  (main feeder).  The cable is run in a insulated area of the floor joists. Is the ampacity of the cable determined at 60 degrees because Art- 338.10 (B) 4  or does  Informational note #2 allow the use of table 310.15 (B) 7 and the 4/0 cable is good for 200 amps?

Answer: The statements in the question are not exactly true but yes you can feed the sub-panel in this question with the 4/0 Alum SER 4 plex. 338.10(B)(4)(a) interior installations must comply with Article 334 Part 2 except for 334.80, therefore the ampacity limitations for NM cable do not apply to SER.

6. Are the conductors between a 30 amp breaker and a 30 amp fused disconnect feeding a single air conditioning unit defined as a feeder or a branch circuit? Would the answer change if the fuses in the 30a disconnect are reduced to 20 amps to meet the nameplate rating of the equipment?

Reference: NEC 100 – Feeder / Branch Circuit

Answer: Q1) Yes it is a Feeder

Q2) No

7. What size equipment bonding jumper is required to connect a 125-volt, 20-amp duplex receptacle, located in the patient care area, to the patient equipment grounding point of a critical care area located in a health care facility?

Answer: Equipment bonding jumper connected to the grounding point shall not be smaller than # 10 AWG

Reference: 2014 NEC 517.19(D) 2011 NEC 517.19(C)

Reference grounding point is defined at 517.2 as “The ground bus of the panelboard or isolated power system panel supplying the patient care area.”

Though an optional feature a patient equipment grounding point continues to be provided by many hospital equipment manufacturers and is specified by consulting engineers. The objective is to reduce any potential difference between conductive surfaces in the patient care vicinity. Also see NFPA 99:3.3.141

8. Is it permissible to install an 8” piece of ¾” EMT with set screw connectors between the bottom of a panel (below live parts) and a 3R pull box installed outdoors?

Reference: NEC 314.15 and 110.3(B), 2014 UL White Book, Pg. 174, Electrical Metallic Tubing Fittings (FKAV)

Answer: No, See NEC 314.15, which states that in damp or wet locations, “Boxes, conduit bodies, outlet box hoods, and fittings installed in wet locations shall be listed for use in wet locations.” A set screw fitting would not be Listed as a suitable for wet locations or rain tight. See EMT Fittings (FKAV) in the 2014 UL White Book.

9. A 400 amp service is installed using 500 KCMIL copper conductors. Based on table 250.66 a 1/0 copper conductor is required for the grounding electrode conductor. Is it permissible to instead install 2- #2 AWG copper conductors in parallel instead of the single 1/0 for the GEC?

See 250.62 for the material permitted for grounding electrode conductors. There is no provision in Article 250 for parallel grounding electrode conductors.

10. We have an Eaton panelboard that does not recognize a 208v three pole breaker to be series- rated with a Type ( J ) fuse. Could we install three single pole breakers and use a listed 3- pole tie handle to achieve the series rating?

225.33(B) Single-Pole Units. Two or three single-pole switches or breakers capable of individual operation shall be permitted on multiwire circuits, one pole for each ungrounded conductor, as one multipole disconnect, provided they are equipped with identified handle ties or a master handle to disconnect all ungrounded conductors with no more than six operations of the hand.

Article 100 Definitions

Identified (as applied to equipment). Recognizable as suitable for the specific purpose, function, use, environment, application, and so forth, where described in a particular Code requirement.

11. We have multiple roof top exhaust fans that have starters controlling them. These starters are “hand/ auto/ off” type with heaters and fuses in them. A common practice is to locate these controllers above the ceiling below the units that are on the roof. Is this location permissible?

Reference: 404.8(A) Exception Number 2, 430.2, 430.102

Yes, 404.8(A) Exception Number 2, allows for motor controllers (switches) to be located higher than 2.0 meters and to be accessible by portable means.

430.2 Controller. For the purpose of this article, a controller is any switch or device that is normally used to start and stop a motor by making and breaking the motor circuit current.

 Switch, Motor-Circuit. A switch rated in horsepower that is capable of interrupting the maximum operating overload current of a motor of the same horsepower rating as the switch at the rated voltage.

 430.102 states that the requirements for the disconnects for the motor and the controller. However, it does not state where the controller is permitted to be installed.

12. UL requires exhaust fans that are in a damp location to have GFCI protection. Is the exhaust fan for a residential or commercial hood considered to be in a damp location?

12. UL requires exhaust fans that are in a damp location to have GFCI protection. Is the exhaust fan for a residential or commercial hood considered to be in a damp location?

Answer: Reference: Art. 100 Definition of Damp Location, NEC 110.3(B)

No, the definition of Location, Damp. Locations protected from weather and not subject to saturation with water or other liquids but subject to moderate degrees of moisture. Informational Note: Examples of such locations include partially protected locations under canopies, marquees, roofed open porches, and like locations, and interior locations subject to moderate degrees of moisture, such as some basements, some barns, and some cold-storage warehouses.

Look at the installation provided with the Listed Hood.

13. Can a listed deck box for pool lights be located in a wall with an access cover for aesthetic reasons?

Answer: No

Code Reference: NEC 314.20; 314.29; 680.24(A)(2)(c); and 110.3(B)

I could not find a listed flush deck box for an Article 680 environment that was listed as a swimming pool junction box and identified to be installed in an orientation other than horizontal flush in the deck.

314.20 requires boxes in walls or ceilings to have the front edge of the box to not be set back more than 6 mm (¼ in.). from the surface. It would seem that the aesthetic access cover over the flush deck box would be set the deck box back more than 6 mm (¼ in.) from the surface of the wall.

314.29 requires boxes to be installed so that the wiring contained in them can be rendered accessible without removing any part of the building or structure.

14. We have a 6- story building with about 20 low- voltage cabinets installed in 10 different locations; most of them are for 24v card readers. Is it required to ground or bond every low voltage cabinet that contains low voltage cables for these card readers?

Answer: Yes if supplied by a Transformer if the supply system exceeds 150V

NEC 725.133 must comply w/ 725.135 and 143 Grounding is not covered 250.3 250.112(I) and 250.20(A)

15. Does a 480-volt, 1600-amp frame breaker with an 800-amp trip plug installed require GFCI protection?

Reference: NEC 230.95

The rating of the service disconnect shall be considered to be the rating of …. the highest continuous current trip setting for which the actual overcurrent device installed in a circuit breaker is rated or can be adjusted.

Answer: No

16. When the travelling carnival comes to town, they have a couple of distribution panels located throughout the carnival site. From these distribution panels a feeder ranging from a 60a 3 pole to a 20a 2pole are run to each ride controller. These controllers then supply the rides that typically have motors & lights. Is it required to install an electrode at each controller?

Answer: Not required Reference: NEC Article 525

There are no mandatory requirements in the NEC for the installation of a grounding electrode at these controllers.

17. The industry is seeing inverters that feed multiple lights to obtain emergency lighting instead of individual frog eye or emergency ballasts. Is it required to treat the wiring method as required for generator emergency backup? Must you identify all enclosures and keep the wiring independent?

Reference: NEC 700.10 and 700.12(F)(5)

Answer: Yes, the requirements of 700.10 apply to this installation.

700.12(F) Unit Equipment (5) Emergency luminaires that obtain power from a unit equipment and are not part of the unit equipment shall be wired to the unit equipment as required by 700.10 and by one of the wiring methods of Chapter 3.

18. Is there any situation that can be verified where a installer can use the 90 degree chart for the wires other than adjustment factors? I have done some research and come to realize that even if you use 90 degree wire, 90 degree lugs and terminate on a bus bar that

the equipment is only listed for 75 degrees therefore the 90 degree chart cannot be used. True or false? If false please give an example

Generally, the statement is true particularly for 600-volt class equipment. I have seen an example where conductors with 90C insulation but sized for 75C ampacity can be connected in a junction box outside the panelboard to a conductor with 90C insulation that is sized for 90C by using connectors that are rated for 90C. The process is reversed at the termination end of the feeder or branch circuit. I am not sure how practical this would be but it can be done.

19. Our local utility company requires a cold- sequence installation with current- limiting fuses when the fault current is above 10k to protect the meter. Since the meter is rated at only 10k, is it also permissible to protect the 10k rated breakers with those same fuses ( Note: they do not series rate)

Cold sequence metering is arranged such that overcurrent protection is provided between the utility supply and the meter to provide isolation and protection of the entire metering installation.

No. You would be required to series rate with the downstream circuit breakers.

20. Can NM-B cable be installed in a piece of EMT conduit without a bushing?

Reference: 300.10 Exception 1, 300.12 Exception 1 and 334.15(C)

Response; Maybe, if you are using the EMT as physical protection as permitted in 334.15(B) , then 300.10 Exception 1 and 300.12 Exception 1 allows the EMT to be installed without mechanically or electrical continuity.

334.15(C) states when a piece of conduit or tubing is used in unfinished basements and crawl spaces the raceway shall be protected with a suitable insulated bushing or adapter at the point where the cable enters the raceway.

21. I have several electricians who have been using 14 AWG conductors from a switch to a light on a 20 amp circuit. Some cite tapping, others point to fixture wire sizing to allow them to do it. I have rejected this installation in both cases as it is my understanding that the weakest link in the circuit needs to be the OCPD (Over Current Protective Device). They often state that the light is only using half an amp etc. so what’s the concern? Are they correct?

Answer: NEC 240.4, 310.15, 240.4(E), 240.21, 210.19

The light may only be drawing ½ an amp, but unless it is 18 inches or shorter, they have to use the 12 AWG on a 20A circuit. I am assuming the circuit is being run with THHN. Since these are THHN conductors they are not considered as fixture Wire. Fixture wire is only those types of conductors detailed in 402.3.

NEC 240.4 states Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.15, unless otherwise permitted or required in 240.4(A) through (G). Table 310.15(B) refers you to 240.4(D) for 14 AWG which permits 15A max ampacity.

NEC 240.4(E) addresses tap conductors. (E) Tap Conductors. Tap conductors shall be permitted to be protected against overcurrent in accordance with the following:

N/A (1) 210.19(A)(3) and (A)(4), Household Ranges and Cooking- N

Appliances and Other Loads

N/A (2) 240.5(B)(2), Fixture Wire

(3) 240.21, Location in Circuit

N/A (4) 368.17(B), Reduction in Ampacity Size of Busway

N/A (5) 368.17(C), Feeder or Branch Circuits (busway taps)

N/A (6) 430.53(D), Single Motor Taps

NEC 240.21 (A) states:

(A) Branch-Circuit Conductors. Branch-circuit tap conductors meeting the requirements specified in 210.19 shall be permitted to have overcurrent protection as specified in 210.20.

210.19(A)(4) States:

(4) Other Loads. Branch-circuit conductors that supply loads other than those specified in 210.2 and other than cooking appliances as covered in 210.19(A)(3) shall have an ampacity sufficient for the loads served and shall not be smaller than 14 AWG.

Exception No. 1: Tap conductors shall have an ampacity sufficient for the load served. In addition, they shall have an ampacity of not less than 15 for circuits rated less than 40 amperes and not less than 20 for circuits rated at 40 or 50 amperes and only where these tap conductors supply any of the following loads:

(a) Individual lampholders or luminaires with taps extending not longer than 450 mm (18 in.) beyond any portion of the lampholder or luminaire.

(b) A luminaire having tap conductors as provided in 410.117.

(c) Individual outlets, other than receptacle outlets, with taps not over 450 mm (18 in.) long.

(d) Infrared lamp industrial heating appliances.

(e) Nonheating leads of deicing and snow-melting cables and mats.

Exception No. 2: Fixture wires and flexible cords shall be permitted to be smaller than 14 AWG as permitted by 240.5

22. Are the PV output conductors that are connected on the supply side of a service disconnect as permitted in 705.12 (A), considered service conductors when they don’t meet the definition of a service?

Answer: No

Code Reference: Article 100; 705.12(A); 230.82(6)

Article 100 Definitions:

Service. The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.

Service Conductors. The conductors from the service point to the service disconnecting means.

Feeder. All circuit conductors between the service equipment, the source of a separately derived system, or other power supply source and the final branch-circuit overcurrent device.

Per our definitions, the PV output conductors are not supplied by the utility; therefore, they cannot be called service conductors. Article 690 and the PV industry treat these conductors as service conductors, but they are not service conductors. They are considered feeder conductors.

Section 705.12(A) establishes the allowance for supply-side PV connections. A supply-side connection is made on the supply or utility side of the service disconnecting means for the existing building or facility. Section 705.12(A) refers to Section 230.82(6).

Of course, this section is in Chapter 2 of the Code dealing with services, and this section allows solar photovoltaic systems or interconnected electric power production sources to be connected on the supply side of the service disconnecting means.

23. I recently installed a 300 ampere, 277/480 volt service located on a pole barn structure. As there is no concrete footing or foundation and there is no water supply to the building, I drove two 5/8" diameter, 8-foot long, copper-clad ground rods below the service equipment. I ran a single 6 AWG copper grounding electrode conductor to the closest ground rod, ran it unspliced through the approved ground clamp and then on to the second ground rod. The inspector required that I install an individual 6 AWG copper grounding electrode conductor from the service equipment to each ground rod. Of course to pass the inspection and get power turned on, I did what he asked. I recently attended an IAEI class on Soares Grounding and Bonding and feel that both methods would meet NEC requirements but that my initial installation should have been approved.

Answer: You were correct Part 3 of Article 250 covers your installation 250.50 requires a grounding electrode “system” consisting of all electrodes “ present” since none were available you were required to drive an electrode per 250.52, 250.53(A) and be connected per 250.66(A) & (B)

24. I installed a pump for a rancher at a location served by a 120/208 3 phase service. The pump supplied was a 480v 3 phase only. I installed a standard, step- down 277/480 to 120/208 transformer by reversing the primary and secondary to supply the 480v for the pump. The 480v side (originally the primary) has no XO connection. Do I need to ground one of the phase conductors, creating a corner grounded delta secondary to provide a ground fault return path back to the transformer?

Answer: If the HV side is a delta connection then the rated voltage should be 480v and not 277/480. No, grounding the secondary is not required see 250.20(B) but the choice is really application dependent. Additionally, follow manufacturer’s instructions and make no connection to the XO on the wye side.

2014 NEC

450.11(B) Source Marking. A transformer shall be permitted to be supplied at the marked secondary voltage, provided that the installation is in accordance with the manufacturer’s instructions.

25. When the AHJ does his inspection and notices 1 or multiple violations in a listed piece of equipment, does the AHJ have the duty or even the right to contact the testing laboratory to discuss the “violation”?

Reference: NEC 90.7 – Examination of Equipment for Safety :

… It is the intent of this Code that factory-installed internal wiring or the construction of equipment need not be inspected at the time of installation of the equipment, except to detect alterations or damage, if the equipment has been listed by a qualified electrical testing laboratory that is recognized as having the facilities described in the preceding paragraph and that requires suitability for installation in accordance with this Code.

Answer: Listed equipment is evaluated in accordance with specific Product Standards. These standards are not necessarily identical to NEC requirements. Observation of possible violations are always welcome by testing laboratories. There are no NEC requirements that would mandate contacting the testing agency. Fortunately as an IAEI member and attendance at local and Section Meetings, such as here, affords that networking and gives contact information to that aides in resolving such concerns with the various testing agencies.

26. Does the metal faucet on a hydromassage bathtub need to be bonded the same as the circulating pump motor when the rest of tub has plastic water pipes?

Reference: 680.74

Answer: No. Per 680.74 the metal piping system and grounded metal parts in contact with the circulating water shall be bonded together and connected to the terminal on the circulating pump that is intended for this purpose. A metal faucet that is fed from plastic water pipes is not considered to be part of a metal piping system.

27. We are wiring a condominium that is basically a duplex. It has two water mains coming in from the street. The service wires to the panels are run under the garage slabs to opposite sides of the building. The inspector says we can’t simply go from each panel to the unit’s individual copper water main. He says we have to connect each water main to each other by running a #4 AWG copper wire between the two units. He also told me that I have to tie both sets of ground rods to the underground metal water pipe. This seems excessive as they come out of their respective panels and the grounding electrode conductors from these panels go to the water pipes. How do I have to do this?

Answer: If a building separation fire wall is installed, there is basically two buildings in one structure. The rule in 250.50 is that all the grounding electrodes that are present at each of the two buildings be bonded to create a grounding electrode system. Each

building is considered separately. The size of the bonding jumper(s) is determined from Table 250.66 based on the size of the ungrounded service-entrance conductor(s).

If a building separating fire-wall is not installed, one building remains. A single grounding electrode system is created by connecting both water pipe electrodes together. A grounding electrode conductor is installed from each service to the grounding electrode system.

Don’t forget that water pipe grounding electrodes are required to be supplemented with another grounding electrode(s) from 250.52(A)(2) through (8).

28. A 400A service is made up of two 200A main breaker panelboards that are connected together by nipples. Can the service conductors pass through one of the cabinets to supply the other panelboard?

Yes, cabinets, cutout boxes, and meter socket enclosures can be used as a raceway for conductors that feed through.

• Conductors must not fill the wiring space at any cross section to more than 40% (See Section 312.8(1))

• Splices and taps can be installed in cabinets, cutout boxes, or meter socket enclosures if the splices or taps do not fill the wiring space at any cross section to more than 75% (See Section 312.8(2))

• A warning label complying with 110.21(B) is applied to the enclosure that identifies the closest disconnecting means for any feed-through conductors. (See Section 312.8(3))

29. The plans for a new office building show there is skeleton-tube neon installed inside. Is this neon required to be listed?

Reference: 600.3(A)

No. See 600.3(A) Field-Installed Skeleton Tubing. Field-installed skeleton tubing shall not be required to be listed where installed in conformance with this Code.

30. Where can we find a code section that prohibits the attachment of a male plug on the end of a section of NM for a garbage disposal? I have a reference site that points to Table

400.4 which doesn't list NM. Or would it be Article 334 - "closely follow the building surface, "securing and supporting"?

Reference: NEC 422.16(B), AXUT Pg. 81 in UL White Book and 110.3(B)

Answer: NEC 422.16(B) allows for plug connection only when connected to flexible cord. Also, NEC 110.3(B), plugs are only Listed for use on flexible cord see Attachment Plugs, Fuseless (AXUT) on page 81 in the 2014 UL White Book. See the Guide Information for AXUT under the heading Terminals which states “Terminals of appliance couplers, appliance and flatiron plugs, attachment plugs, cord connectors and table taps are intended for use with stranded copper conductors of the type used in flexible cord.”

31. Why is temperature derating in 310.15 (B) (3) (c) still required for rooftop installations when it has been shown not to be an issue in a recent IAEI magazine?

Answer: Wow! I must have missed that issue of the IAEI News magazine! CMP-6 rejected the proposal to remove 310.15(B)(3)(c) from the Code.

Code Reference: 310.15(B)(3)(c)

CMP 6 Panel Statement ROP 6-18: Technical substantiation was provided during the 2008 and 2011 Code cycles to support the ambient adjustment factors to conduit exposed on rooftops. This testing proved to the panel’s satisfaction that the adjustments are required. Additional testing has been provided via a fact-finding report in Proposal 6-31 during the 2014 cycle to support the application of adjustment factors. Adequate technical substantiation has not been provided to support removal of this requirement.

Rooftop Wiring Temperature-Field Installation Experiment (May-June 2013)

By: Howard Herndon

32. Is it a violation to have open wire nuts in a non- plenum ceiling for class 2 & 3 wiring methods for signs & occupancy sensors or does 300.15 apply?

Answer: No, Article 725 permits open cable and there are no requirements for placing splices in a box.

33. I have 24- unit multi-family building that was built in 1978 and thus the 1978 NEC would apply. In reviewing the main electrical equipment / boiler room it was noted that

an interior electrical generator was installed at the time the building was constructed and appeared to be non –operational. Doesn’t NEC 700.3(B) & (D) need to be addressed? Under section (B) the generator system shall be tested periodically on a schedule (normally monthly) to ensure the system is maintained in proper operating condition. Under section (D) a written record shall be kept of such tests and maintenance done on the system. As was discussed with the maintenance person a log needs to be made up of the operations test and date and time frame of the test and copy available on the site. Normally we as electrical inspectors only get back into those building to answer an electrical complaint. Who is the responsible party to be sure items are corrected and followed up on? The local volunteer FD and their inspection reports never seem to address this concern. What can I do in the future to solve this problem? Electrical and fire safety is everyone’s concern.

Reference: NEC 700.3(B) & (D)

Question:

Who is the responsible party to be sure items are corrected and followed up on? The local volunteer FD and their inspection reports never seem to address this concern. What can I do in the future to solve this problem?

Answer: Not the Building Department (After CO Issued)

The Fire Department

34. Where is the disconnecting means for a Class 2 remote- control transformer required to be located?

Reference: NEC Article 725 - NEC 450.14

450.14 Disconnecting Means. Transformers, other than Class 2 or Class 3 transformers, shall have a disconnecting means located either in sight of the transformer or in a remote location. Where located in a remote location, the disconnecting means shall be lockable in accordance with 110.25, and its location shall be field marked on the transformer.

Answer: Disconnecting means would not be required unless specifically required in Chapter 1 – 4.

Article 725 is silent as to Class 2 Transformer disconnecting means. Although 725.127 states in part …Conductors and equipment on the supply side of the power source shall be installed in accordance with the appropriate requirements of Chapters 1 through 4.

Section 450.14 exempts Class 2 or 3 transformer disconnecting means.

Section 430.75 in subsection (A) requires the motor control circuits to be disconnected from all sources of power when the disconnecting means is in the open position. Subsection (B) would only require the control transformer to be on the load side of the disconnecting means for the motor control circuit when located in the controller enclosure.

35. Can I install a receptacle for the basin in a bathroom near the floor as long as it is within 3’ of the basin? The basin is a free-standing type and does not have a countertop associated with it.

Reference: 210.52(D)

Answer: No. The receptacle may not be located more than 12 inches below the top of the basin.

36. I have an existing building where I am upgrading the electrical service. The building is masonry and wood frame walls. The roof system is steel bar joists which are supported by steel beams which are then supported by the concrete footings. Is it required to bond to the steel bar joists? The basement ceiling is Spancrete, which is supported with 2 steel I beams. Would these 2 steel beams in the basement be required to be bonded to the electrical service?

Answer: The structural metal is required to be connected as a grounding electrode if it qualifies as “the metal frame of the building or structure” under 250.52(A)(2). If not, bonding of the structural metal is required by 250.104(C) if it qualifies as, “Exposed structural metal that is interconnectedto form a metal building frame.”

There would be no harm done if the 2 steel I beams in the basement are bonded. However, they are not required to be if they do not qualify as mentioned in 250.104(C).

37. Can I use Type NM cable to connect recessed fluorescent fixtures in a suspended lay-in ceiling in a retail store? Section 334.30(B)(2) seems to permit this.

334.30(B) Unsupported Cables. Nonmetallic-sheathed cable shall

be permitted to be unsupported where the cable:

(1) Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.

(2) Is not more than 1.4 m (41⁄2 ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of connection are within an accessible ceiling.

Answer: No

334.12 Uses Not Permitted.

(A) Types NM, NMC, and NMS. Types NM, NMC, and NMS cables shall not be permitted as follows:

(1) In any dwelling or structure not specifically permitted in 334.10(1), (2), (3), and (5)

(2) Exposed in dropped or suspended ceilings in other than one- and two-family and multifamily dwellings

(3) As service-entrance cable

(4) In commercial garages having hazardous (classified) locations as defined in 511.3

(5) In theaters and similar locations, except where permitted in 518.4(B)

(6) In motion picture studios

(7) In storage battery rooms

(8) In hoistways or on elevators or escalators

(9) Embedded in poured cement, concrete, or aggregate

(10) In hazardous (classified) locations, except where specifically permitted by other articles in this Code.

38. When hooking up a 100 amp mobile home feeder, can I use a 200 amp breaker in the pedestal and use tap rules to the panel?

Reference 550.10

No, the requirement for power to a mobile home in Section 550.10 calls for a feeder. There is no provision to use a tap.

39. I have installed approximately 50 - 4’ fluorescent light fixtures in a retail store and have direct- wired the factory- supplied cord into a 4” square junction box. The Inspector has required me to install an attachment plug on to the end of cord and he is citing NEC 410.62(C)(2). Is he correct?

Reference: 410.62(C)

Answer: Yes, the inspector is always right. If the luminaires are chain, cable or hook hung luminaires, then it is possible to wire the cord to a junction box if these are required to be height adjustable in accordance with the adjusting provisions in 410.62(B).

40. I have a large county estate home being built with a large center living room and fireplace that is open on the inside for two and a half stories; with a slab on grade construction in that part of the house. The owners have many small children and have left a large (24”) inch oak tree in the room and about (15’) feet high with a tree house and ladder to get up to it. This is all covered with the house’s roof above it. My question is, how do I treat the area around the cut off tree and what do I do with the tree house area since it has a door and (3) windows installed?

Answer: This is an AHJ call.

Code Reference: None [Maybe 210.52(A)]

This is an AHJ call. If I were the AHJ, I would not consider the treehouse as “living area” and would not require receptacle spacing, smoke alarms, etc. If you wanted to tread the tree trunk like a 2 ft. wall or column and require a receptacle outlet at the trunk, I could be talked into that.

41. I have a SFD house that is going to have a 60 ampere to 100 ampere up-grade and it has a # 8 Copper armored cable for a grounding electrode conductor going outside to two ground rods and an old copper ground ring (#8 copper) around the house. Is this acceptable for use with the new service?

Answer: Yes, 250.66 and Table 250.66

42. Is it allowable to have a switched receptacle outlet (for a lighting outlet) for a stairway? Does installing a midpoint landing have any bearing on the issue?

Reference: NEC 210.70(A)(2)c

Answer: Q1) No

Q2) No – Landing can create a need for another switch but still has no bearing on a switched receptacle outlet.

43. We have a free-standing medical building that doubles as the doctor’s consultation office and surgery center on a outpatient basis. He has a pre-op, post op and surgery room which does plastic surgery, therefore patients are often under a general anesthesia. How do we treat these rooms? In the 2014 NEC, all surgery rooms in hospitals require 36 receptacles, they are all required to be GFCI-protected or ungrounded. How does a jurisdiction address this in the plan review process? This set up is becoming common.

Reference: NEC 517.1, 517.5 Informational Note No. 1 to definition of “patient care space,”

Answer: In order to answer the question we need to properly define the area in question. We need to keep in mind , the governing body of the facility designates patient care space in accordance with the type patient care anticipated and with the definitions of the area classification as referenced in Informational Note No. 1 for the definition of “patient care space.” The term “surgery room” as stated in the question, is not defined in the NEC a surgery room could possibly be designated by governing body of the facility as a critical care space requiring compliance as such (requiring the min. 36 receptacles). Normal procedures administered in a pre-op or post-op would typically be considered a “general care space.” The plan review should be based on the patient care spaces anticipated and designated.

44. Are receptacles installed for a countertop in a dining room required to be GFCI protected? The counters are not within the kitchen, and 1 counter is actually used as a desk area.

Reference: 210.52(D)

Answer: No. The receptacle may not be located more than 12 inches below the top of the basin.

45. It appears the grounding electrodes are now allowed to be installed in many cases without being continuous, they can now be spliced. When and where can these grounding electrode conductors be spliced? What type of splices are allowed? What is the rationale behind the changes over the last few Code cycles for this change?

Answer: The rule is located in 250.64(C). Note that the bold-face title of the section continues to be “Continuous”. It reads,

If necessary, splices or connections shall be made as permitted in (1) through (4):(1) Splicing of the wire-type grounding electrode conductor shall be permitted only by irreversible compression-type connectors listed as grounding and bonding equipment or by the exothermic welding process.

(2) Sections of busbars shall be permitted to be connected together to form a grounding electrode conductor.(3) Bolted, riveted, or welded connections of structural metal frames of buildings or structures.(4) Threaded, welded, brazed, soldered or bolted-flange connections of metal water piping.

The reason for the allowed splices or connections? To allow flexibility for installations to be made as necessary. It also recognizes that grounding electrode conductors that consist of components such as building structural metal are not installed in one continuous length.

Note that the NEC also allows the use of ¼ x 2 busbars to make connections of the grounding electrode conductor and grounding electrode bonding conductors. See 250.30(A)(5), 250.66(D)(3) and 250.64(F)(3).

Some may consider these connections to be splices of the grounding electrode conductor. However, these are permitted connections and are not a splice in the truest sense of the word.

46. I plan to use 2 AWG aluminum SER cable for the 100-ampere feeders to each apartment in a multi-family dwelling. The length of the home run varies but is under 100 feet. The last 4-feet of the run is through an insulated wall cavity. If the voltage is 120/240, single phase, can I still protect the feeders at 100-amperes? If the voltage is 120/208, single phase, can I protect the feeders at 90-amperes by using the exception to 310.15(A)(2)?

310.15 Ampacities for Conductors Rated 0–2000 Volts.

(A) General.

(1) Tables or Engineering Supervision. Ampacities for conductors shall be permitted to be determined by tables as provided in 310.15(B) or under engineering supervision, as

provided in 310.15(C).

240.6 Standard Ampere Ratings.

(A) Fuses and Fixed-Trip Circuit Breakers. The standard ampere ratings for fuses and inverse time circuit breakers shall be considered 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600, 700, 800, 1000, 1200, 1600, 2000, 2500, 3000, 4000, 5000, and 6000 amperes. . . .”

110.14(C) Temperature Limitations. The temperature rating associated with the ampacity of a conductor shall be selected and coordinated so as not to exceed the

lowest temperature rating of any connected termination, conductor, or device. Conductors with temperature ratings higher than specified for terminations shall be permitted to be used for ampacity adjustment, correction, or both.

ARTICLE 338, Service-Entrance Cable: Type SE and USE

338.10 Uses Permitted.

(B) Branch Circuits or Feeders.

(4) Installation Methods for Branch Circuits and Feeders.

(a) Interior Installations. In addition to the provisions of this article, Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334, excluding 334.80.

Where installed in thermal insulation the ampacity shall be in accordance with the 60°C (140°F) conductor temperature rating. The maximum conductor temperature rating shall be permitted to be used for ampacity adjustment and correction purposes, if the final derated ampacity does not exceed that for a 60°C (140°F) rated conductor.

Informational Note No. 1: See 310.15(A)(3) for temperature limitation of conductors.

Informational Note No. 2: For the installation of main power feeder conductors in dwelling units refer to 310.15(B)(7).

47. If I have a raceway under a building, or encased in concrete on an outside wall beneath grade on an exterior wall, would I have to seal the raceway where it enters the building? If so, would I have to seal each end?

Reference 300.7(A)

300.7(A) requires raceways to be sealed where known to be subjected to different temperatures, and where condensation is known to be a problem such as passing from a the interior to the exterior of a building. Only the end where warm air would enter the cold section is required to be sealed.

48. The new Orion F-bay fixtures I plan to use for warehouse lighting have a “platform” connection. The manufactured “cord-whips” come with a 3- or 5-pin connector. The connector plugs into a factory mounted socket on the back of the ballast compartment.

The other end of the cord is intended to connect to the outlet box with suitable strain relief and run into the outlet box. If I mount the boxes directly above the fixture, would this connection meet 410.62(C)(1)?

Reference: 410.62(C) (1)(c)

Answer: No, 410.62(C)(1)(c), requires the cord whips to terminate in a grounding type attachment plug or a manufactured wiring system connector. So from what was described as a “platform connector”, I assume is a manufactured wiring system connector, however, the other end of the cord that connects to the building would also have to terminate in a manufactured wiring system connector or attachment plugs. There are some of these fixture whips with 12AWG cord that terminate in a mws connector and the other end is a pigtail, however, that pigtail is intended to get wired into the luminaire not the building wiring box.

These MWS cord whips may be Listed/Certified in a couple categories. Manufactured Wiring Systems are Certified/Listed under the product category Manufactured Wiring Systems (QQVX) located on page 429 in the 2014 UL White Book. There may also be some of the cord fixture whips that terminate in a MWS connector Certified/Listed under the product category Luminaire Fittings (IFFX) located on page 226 in the 2014 UL White Book.

49. Recently a code inspector mentioned to us that building service entrance conductors need to be sized for 100% of the service entrance main circuit breaker rating. Is this correct, or does NEC 240.4 (B) still apply for service entrance conductors? In our particular situation we had an 800A MCB with 2~500 Kcmil conductors per phase. The inspector indicated that we could not use these conductors because the ampacity ratings listed in Table 310.16(B)(16) indicated the conductors were only good for 380 amps, 760 amps total. We were asked to up-size the conductors to 2~600 Kcmil per phase.

Answer: Yes, this is correct. As usual, the AHJ is correct again! 240.4(B) is for sizing overcurrent protection, not conductors.

Code Reference: 230.42(B)

230.42(B) Specific Installations. In addition to the requirements of 230.42(A), the minimum ampacity for ungrounded conductors for specific installations shall be not less than the rating of the service disconnecting means in 230.79(A) through (D).

50. Can I use 1/2-inch flexible metal conduit to fish in receptacle outlets in an existing building? I used 12-AWG THWN wire with fittings on the outside of the flex and I only put two wires in each run. Now I was told I have to pull in a ground wire. Is this right?

Answer: FMC is covered in Article348, 348.10 permitted uses will allow the practice of fishing. It is approved as an EGC with conditions see; 250.118(5) if the length exceeds 6 feet then an EGC is required fittings must be listed and the OC device cannot exceed 20 amperes. Where required or installed, equipment grounding conductors shall be installed in accordance with 250.134(B). Where required or installed, equipment bonding jumpers shall be installed in accordance with 250.102

51. I have a bathroom that has laundry equipment in it. I know the receptacles in this room need GFCI protection. Would AFCI protection be required because this room is also part laundry room?

Reference: NEC 210.12 - AFCI

Answer: Yes – 120V, 15 and 20A laundry branch circuits

52. A new condo we are working on has lighting fixtures that are antiques and were bought on the internet. There does not appear to be a listing mark on the fixtures. Are these lighting fixtures required to be listed, or can they just be rewired and installed?

Reference: NEC 410.6 – Listing Required

410.6 Listing Required. All luminaires, lampholders, and

retrofit kits shall be listed.

Answer: The luminaires would be required to be listed or a field evaluation could be requested.

53. Can NM cable be used outside for temporary wiring? How about if I put it in a PVC sleeve?

Reference: 590.4(B), 590.4(C), 334.12(B)(4), 300.9, Rigid Nonmetallic PVC Conduit (DZYR)

Answer: No, 590.4(B) and (C) only allow NM cable inside the building for feeders and branch circuits. 334.12(B)(4) does not allow NM cable in wet or damp locations.

All Rigid nonmetallic PVC conduit is intended for installation as a rigid nonmetallic raceway. Use as a sleeve and not a raceway would be a violation of 110.3(B).

Even if we call it a raceway, then 300.9 considers the interior of a raceway above grade to be a wet location.

54. When “Chicago” type grid systems are used to hang drywall ceilings, I’ve been allowed to secure and support MC cable onto the Chicago grid system.  I just want to confirm that this is acceptable before we get too far along.

Answer: I am not sure what a “Chicago” type grid system is as I am from the Northwest! Irrespective, 300.11(A) contains the sentence, “Cables and raceways shall not be supported by ceiling grids.” So, other means of support such as a trapeze or, when selected and sized appropriately, ceiling support wires may be installed for the support of Type MC cables.

55. I have a project coming up with a "Mother-in law" apartment above the detached garage. Would that need to be a 100A service?

230.79(C) One-Family Dwellings. For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire.

225.39 Rating of Disconnect.

(C) One-Family Dwelling. For a one-family dwelling, the feeder disconnecting means shall have a rating of not less than 100 amperes, 3-wire.

Dwelling Unit. A single unit, providing complete and independent living facilities for one or more persons, including permanent provisions for living, sleeping, cooking, and sanitation

56. I have installed a main distribution panel (MDP) which supplies many feeders and branch circuits. I have installed a metal wireway above the MDP and have used 4 PVC conduits, 20” in length, to connect the MDP to the wireway. Can I install only 1 equipment grounding conductor thru only 1 of the PVC conduits in order to ground the metal wireway? The conduits exiting the wireway to supply the loads are all metal conduits, IMC or EMT.

Reference: 250.134(B)

No, 250.134(B) requires the equipment grounding conductor to be contained within the same raceway, cable or otherwise run with the circuit conductors. The only Exception to this for this scenario, is if this was a DC application in accordance with Exception Number 2. 

57. I found an LED conversion kit for a recessed incandescent can I want to use in a closet. Are these things legal? What are the clearances for this can in a closet?

Reference: 410.6, 410.16(A) and (C), 110.3(B)

Answer: I would say yes if it is a Certified/Classified retrofit conversion kit as required by 410.6 with an enclosed light source. Per 410.16(A)(1) or if it is marked as suitable for use

installation within the closet storage space and permitted in 410.16(A)(3). 410.16(C)(3) would dictate the minimum clearances which in this case of a completely enclosed light source would be 6 inches.

UL Certifies/Lists LED retrofit kits under the product category Light Emitting diode Retrofit Luminaire Conversion Kits (IFAR) located on page 217 in the 2014 UL White Book. The marking on the retrofit kit will identify what types of luminaire that it was certified for use in or in accordance with the installation instructions.

58. I am trying to find out whether we will need to rewire the current X-ray machines at a dental facility. After a few weeks of not being able to find this manual or instructions online; can we run a ground from the X-Ray to the metal j-box that sits behind the unit? The dental equipment supplier has stated this model was discontinued 15-20yrs ago so we will not be able to find any info.

Answer: Yes, maybe.

Code Reference: Part V of Article 517 [517.78(C)], Part VII of Article 250 [250.130(C), 250.134]

If the existing wiring method is an acceptable wiring method for the application, the required equipment grounding conductor can be ran with the wiring method inside or outside of the raceway.

517.78(C) Non-Current-Carrying Metal Parts. Non-current-carrying metal parts of X-ray and associated equipment (controls, tables, X-ray tube supports, transformer tanks, shielded cables, X-ray tube heads, etc.) shall be connected to an equipment grounding conductor in the manner specified in Part VII of Article 250, as modified by 517.13(A) and (B).

59. I am installing a new 600 amp 120/208 volt overhead electrical service. The service equipment consists of 1- 600 amp tap box in the center, with a 400 ampere fused service disconnect to the left and a 400 ampere 2- position meter stack cabinet to the right of the tap box. All of the equipment is connected together with bus bars. Am I allowed to install the grounding electrode conductors into the utility tap box which will be sealed? The only grounding electrode present at the building is copper water pipe located on the opposite end of the building. Am I required to install 1 or more grounding electrode conductors to the new electrical service, and where will these need to be terminated?

Answer: This is a two part question, 1) No, This connection must be accessible. 250. 24(A)(2)

2) yes the CU. Water pipe must be supplemented 250.53(D)(2) Where = any point from the service point to the main service disconnect 250.24(A)(1) through (A)(5)

60. Article 210.8(6) states that receptacles for the counter top must be GFCI protected. I agree with this. Confusion has arisen from the Analysis of the Code changes about the dishwasher and disposal receptacle. The analysis states that dishwasher and disposal, whether hardwired or cord and plug connected, shall be GFCI protected as well. The code stated differently. The commentary in 210.8(6) 2nd paragraph states that they are not required to be protected. This also includes the refrigerator. The receptacle for the refrigerator is for a specific appliance, not he counter top, therefore it is not required to be GFCI protected although it is within 6 feet of the sink. When installing a generator to an existing 200 amp service with a 200 amp transfer switch, is there any consideration to the size of the generator?

Reference: NEC 210.8(A) GFCI

NEC 702.4(B) Capacity

Answer:

Q1) GFCI required that serve the counter top and those within 6ft of the sink. A refrigerator receptacle within 6ft of sink must be GFCI protected.

Q2) If the transfer switch is automatic it must either pick up the entire load or a load management system employed.

61. I have a house damaged by fire. It occurred in the first floor area and the main panel is down in the basement. The insurance company is saying that the whole service does not have to be replaced and the old panelboard can be reused. But due to the bubbled paint on the outside of the panel I am concerned with possible heating from the fire. Should the panelboard be replaced?

Reference: NEC 110.12(B) Integrity of Electrical Equipment and Connections.

Internal parts of electrical equipment, including busbars, wiring terminals, insulators, and other surfaces, shall not be damaged or contaminated by foreign materials such as paint, plaster, cleaners, abrasives, or corrosive residues. There shall be no damaged parts that may adversely affect safe operation or mechanical strength of the equipment such as parts that are broken; bent; cut; or deteriorated by corrosion, chemical action, or overheating.

Answer: Depends

Although the NEC specifically may not require replacement Section 110.12(B) does appear to play a part in decision. Although the overheating may not have been electric related the ambient temperature would have been exceeded affecting its listing. Another serious effect to consider is

water damage to the equipment caused by fire fighting procedures. In both cases a good reference would be NEMA’s publication “Evaluating Fire- and – Heat Damaged Electrical Equipment”

62. Do the identification requirements for branch circuits also apply to 120 volt control wiring circuits if they are in the same raceway?

Reference: 200.4(B), 200.6(D), 210.5(C), 725.30, Definitions of Branch Circuit and Control Circuit

Answer: Per 200.4(B), more than one neutral must be identified, with no exception for 120 volt control wiring. Per 200.6(D), grounded conductors of different systems must be identified, with no exception for 120 volt control wiring.

210.5(C) requires ungrounded branch circuits from more than one system to be identified.

725.30 requires that Class 1,2,and 3 circuits be identified

No mention of identifying ungrounded control conductors that are not Class 1,2,or 3.

63. A mini-split system has one compressor and two “heads”. One head supplies conditioned air for an elevator equipment room. The other head supplies an adjacent office. Is this arrangement permitted by the Code?

Answer: See 620.37(A). Wiring in Hoistways, Machine Rooms, Control Rooms, Machinery Spaces, and Control Spaces.(A) Uses Permitted.

The section does not seem to permit wiring for the air-conditioning unit that supplies the elevator machine room to be in the machine room. Talk with your electrical inspector. Perhaps you will be allowed to install the wiring method behind the sheetrock. Public Input anyone?

64. Is it required to have 2 sources of power in a doctor’s office that does in- house facial reconstructive surgery, and oral surgery? If so, should the wiring method from the critical branch be installed only in a raceway?

Reference: NEC 517.18 Ex # 2, 500.2

Answer: No. NEC 517.18(A) typically requires one from the normal and one from the critical branch. NEC 517.18 Exception #2, which is located in Part II of 517, does not require the 2

power sources in these types of facilities (doctors offices). Also revised definitions (2014) of patient care areas in 500.2.

Reference: NEC 517.18 Ex # 2, 500.2

Answer: No. NEC 517.18(A) typically requires one from the normal and one from the critical branch. NEC 517.18 Exception #2, which is located in Part II of 517, does not require the 2 power sources in these types of facilities (doctors offices). Also revised definitions (2014) of patient care areas in 500.2.

Doctors and Dentists offices which perform procedures in their offices such as oral surgery, root

canals and facial surgery are not required to have 2 sources of power. NEC 517.18 Ex #2,

500.2

65. A rooftop solar system is installed with 3 strings of panels with AC micro-inverters on the panels. The conductors are then installed in a combiner box and run in conduit through the attic to an AC disconnect. Is an AC disconnect and overcurrent protection required on the roof?

No. The NEC 690 has no requirement, check with the local AHJ

66. To save his company dollars, a contractor dug through his inventory to locate lugs to terminate four parallel runs of 250 kcmil service entrance conductors in a CT enclosure. He installed four single conductor lugs rated for 250 kcmil on Phase A. On Phase B, he installed a quadruple lug rated for 3/0 - 350 kcmil. On Phase C, he installed two double lugs listed for terminating two 4/0 conductors per lug. Do conductors of the all phases have to terminate in the same manner or just the conductors of each phase have to be of the same type of lugs?

• Section 310.10(H)(5) provides the conductors in each phase, polarity, neutral, grounded circuit conductor, equipment grounding conductor, or equipment bonding jumper shall be terminated in the same manner. The language is specific to each phase.

67. A roof top heating / ac unit is placed on metal framing to help distribute the weight. The RTU’s service breaker is now well above 6’7”. Would the installation of a platform be required to get the breaker to a height of 6’7” or less? If so, would the platform have to be 30” x 36” to meet Art- 110.26?

Answer: 404.8 (A) Accessibility and Grouping

Location. All switches and circuit breakers used as switches shall be located so that they may be operated from a readily accessible place. They shall be installed such that the center of the grip

of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 2.0 m (6 ft 7 in.) above the floor or working platform.

67 (c) Would the installation of a platform be required to get the breaker to a height of 6’7” or less?

Reference: 404.8

ANSWER: Yes

35(b) If so, would the platform have to be 30” x 36” to meet Section 110.26?

Reference: 110.26

ANSWER: Yes, but depending on voltage/clearances it may have to be larger

68. Is there any violation in reversing a standard 480v delta/208v wye step down transformer to a step up transformer?

Reference: 2014 NEC 450.11(B)

Answer: No, not as long as the manufacturer’s instructions are followed. This has been done for many years and now included in the 2014 NEC 450.11(B). Pay particular attention that the XO terminal is not connected when the wye side is the primary.

69. Why was the exception for existing feeders for panels supplying pool equipment in 680.25 removed in the 2014 NEC? This causes inspectors problems and adds expense to the job.

• Reference: 680.25

• Answer: Proposal 17-119 was accepted:

• Substantiation: Inspectors struggle with the term “existing” in this section. The grounding and bonding requirements for pools and spas are there for the safety of the users. The exception for “existing” feeders allows the installation of the feeder without an insulated EGC and after some arbitrary time period the installation becomes “existing” and the pool equipment can be installed without this important electrical safety requirement. This should not be allowed.

70. What is the minimum size grounding electrode conductor required to connect to a ground ring that has been increased in size from 2 AWG copper to 250 kcmil copper by the engineer? This installation is for an electrical service fed by six parallel runs of 500 kcmil copper?

Reference: 250.66, 250.66(C), Table 250.66

The size of the grounding electrode conductor shall as specified in Table 250.66 based on the service entrance conductor size. In this case for 3000 Kcmil copper service entrance conductors, that would be a 3/0 Copper conductor. When a ground ring is the electrode, the size of the grounding electrode conductor is not required to be larger than the size of the ground ring conductor and not smaller than 2 AWG copper from the minimum size copper conductor for a ground ring. When the ground ring conductor is increased in size by design, then if required under the basic rule the grounding electrode conductor is sized to the ring but does not have to be larger than required by 250.66 and Table 250.66 with 3/0 AWG copper being the maximum size

71. We have an installation of an x-ray machine and a CT Scanner in a health care facility. At what point does the AHJ stop his inspection and depend on the listing of the equipment? Typically, there is a NEC- required disconnect with THHN to the line terminals. From the load side of that disconnect there is typically a wireway that is designed by the manufacturer but installed by the contractor. From the wireway, the cables will leave go to 1 or more pieces of equipment, go back to the wire-way and ultimately feed the CT or large x-ray machine. From the load side of the disconnect, I normally witness multiple NEC violations such as wire bending radius issues and loss of redundant grounding.

The listing of the X-ray or CT equipment applies to the piece of equipment and the interconnecting cables. The field installation of that machine is not included in the listing and would need to comply with the code. Section 110.3(B) regarding the installation instructions of the piece of equipment is your main tool regarding the installation requirements. The internal portion of a listed piece of equipment would not need to be evaluated by the inspector. The requirement for metal raceways and redundant grounding of Article 517 would still apply. Any field wiring would still need to comply with the National Electrical Code. Article 517, Part V covers x-ray installations, Being Sections 517.70-78.517.75 Equipment Installations. All equipment for new X-ray installations and all used or reconditioned X-ray equipment moved to and reinstalled at a new location shall be of an approved type. The term “Approved” is defined in Article 100 as “Acceptable to the authority having jurisdiction.” 

72. What is the minimum rating of a disconnecting means for an outside feeder supplying a building with only 2 branch circuits?

Reference: NEC 225.39(B)

ANS: The minimum size disconnect required for this particular outside feeder is 30 amperes. 225.39 requires the branch circuit of feeder disconnect have a rating of not less than the calculated load to be supplied as determined by Article 220, Part III for feeders. 225.39 (A) requires a minimum 15 ampere circuit for a single circuit, (B) requires the minimum 30 ampere disconnect as already mentioned, (C) requires for one family dwellings a minimum of a 100 ampere disconnect and then subsection (D) requires a minimum 60 ampere disconnect for all other installation.

30 ampere feeder required to supply this outbuilding which has 2branch circuits.

NEC 225.39(B)

73. Is the wiring method of an eyeglass examination room required to comply with 517.13?

• Yes. 517.13 is about receptacles in a Patient Care Area and in “definitions” of 517.2 it calls that Patient Care Space ‘wherein patients are intended to be treated or examined’

74. A free- standing building is designed for a bank and there are windows for about 75% of the building. Doing an electrical rough inspection, I failed the inspection because there were no show window receptacles. The engineer responded that the bank will not install any electrified signs and stated the windows are there primarily for security and may hang material but will not display electrified signs. Does 210.62 need to apply?

Where the window qualifies as a “show window” 210.62 would apply.

The actual answer in this case lies in the definition of a “show window” in Article 100. There it states a “show window” is one that is used or designed to be used for the display of goods or advertising material, whether it is fully or partly enclosed or entirely open at the rear and whether or not it has a platform raised higher than the street floor level.

So if the window was not designed to be used as a show window and is not being used as a show window 210.62 would not apply.

75. Is it permissible to connect a 240 volt, 4500 watt water heater with a cord and plug?

Reference: NEC 110.3(B), 2013 UL White Book pg. 243 for KSDT

Answer: No. UL Lists water heaters under the product category Household Water Heaters, Storage Tank (KSDT) on page 243 in the 2013 UL White Book. The KSDT Guide Information states these are for permanent connection to a source of supply in accordance with the NEC.

These water heaters are evaluated for compliance with UL 174, the Standard for Safety for Household Electric Storage Tank Water Heaters. UL 174, only permits small capacity storage tank water heaters up to 5 gallons to be cord and plug connected, over 5 gallons they have to be hard wired. I doubt a 4.5kw water heater is 5 gallons or less.

76. Can NM cable be installed outdoors in conduit when its ambient is not exceeded? Does it comply with Section 334.10(A) when it is normally dry 95% of the time in most geographic locations?

Reference: NEC 334.12(B)(4), 300.5, 300.9

Answer: No. Outdoor locations are considered wet or damp locations. Sections 300.5 (underground) and 300.9 (above ground) state that the interior of raceway installed in a wet location shall be considered a wet location. and 334.12(B)(4) does not permit NM cable to be installed.

77. Section 690.43(C) requires that the racking can be used as the equipment grounding conductor if it is identified as a EGC. What does this mean? What was the intent of that verbiage? Should it have a symbol located on the couplings, can the manufacturer write a letter stating it is identified as such. Can the inspector simply make a judgment call? Many states require all equipment be listed by a National testing laboratory

78. We have a water pipe as the only grounding electrode in a residence. Is it required to install 1 or 2 ground rods to supplement the water pipe?

Reference 250.53(D)(2) and 250.53(A)(2)

250.53(D)(2) requires that a metal water pipe grounding electrode be supplemented with another electrode. If ground rods, pipes, or plates are used, 250.53(A)(2) would require a minimum of 2 these electrodes (rods, pipes, or plates) in any combination. The exception to 250.53(A)(2) provides that a single rod, pipe or plate could be used if it is proven by testing that the resistance to earth of the single electrode is 25 Ohms or less.

79. In the 2014 NEC, does Section 690.12 that talks about the rapid shut down of a PV system, apply to residential solar systems?

Yes, 690.12 will applies to all PV Systems and does not exempt out residential applications. There are many different ways to comply with the requirement in the 2014 NEC for rapid shut down of PV Systems.

Rapid shutdown is possible with systems designed with AC modules, DC-to-DC converters, and micro-inverters. Those without them may have to incorporate them or employ other means of isolating and reducing DC power. For smaller residential systems using micro-inverters for individual modules is ideal. If you shut down the power to the building it would activate this unit. Disabling the capacitors in the inverters is the key issue. The rapid shut down is require where we have ten feet of conductor from the array or 5 feet of conductor length as it enters the building.

Yes, 690.12

80. In a Master bath there is a large claw foot tub that is set in a bump-out of the room, the tub is very close to the side wall (2”)  and the ends are 12” from tub . The homeowner would like to install a receptacle at the end of the tub at a height of six feet so they can hang a TV to watch while soaking in the tub. Is this a violation of 406.9 ( C ) ? Are there any dimensions that define this area?

Reference: NEC 406.9(C)

Answer: A receptacle appears to be allowed in this location. The NEC does not have any specific dimensions of the tub area, and it becomes a local AHJ interpretation. NEC 406.9(C) only indicates the receptacle cannot be placed within or directly over the bathtub or shower stall. Also see IAEI 1 & 2 Family dwelling book on page 269.

81. I have received plans for a residential addition. Because of the grade change, the service disconnect will be mounted one foot off the ground. Is there a minimum allowable height for a service disconnect on a residential home?

• NO. Article 230 regarding Services has no requirements. Normal 110.26 general access needs to be considered however you may need to check with the serving Utility.

82. The 2014 NEC 210.52(1) requires one receptacle for each car space. Would a 4plex receptacle at the garage door of a 3 car garage meet this requirement? As an alternative, can I

install a duplex receptacle on the ceiling over each bay to serve the door openers and still be in compliance with 210.52 (1)?

Technically, the “quad plex” (two duplex receptacles) would meet the requirement as there would be one for each car space.

The same would be true where a duplex receptacle was installed for the garage door openers. There would be a receptacle for the door opener and one for the car space. However, if a single receptacle was used for the door opener an additional receptacle would be needed for the car space. Section 210.52(G) specifies the receptacle must be in addition to what has been installed for specific equipment.

83. What is the NEMA rating of an indoor panelboard enclosure subjected to hose down and splashing water?

Answer: NEMA 4, 4X, 6 and, 6P.

84. I seem to be hearing different interpretations on whether an electrical service transfer switch is to be SUSE- rated or not depending on which side of the main it is located. Does it have to be adjacent to the main? Can it be inside or outside from the main and not be required to be within sight of each other? Does it matter if it is SUSE- rated gear as to where it has to be placed or allowed to be placed?

Reference: 230.90(A), 230.91

Answer: Transfer equipment located ahead of the service main must be rated as “Suitable for Use as Service Equipment” (SUSE). Service equipment requirements are found in part VII of Article 230. NEC 230.90(A) requires overcurrent protection in series with each ungrounded conductor and 230.91 specifies the location.

230.91 Location. The service overcurrent device shall be an integral part of the service disconnecting means or shall be located immediately adjacent thereto.

The determination of what is considered “immediately adjacent” must be determined by the AHJ but the requirement does not require the disconnect and overcurrent protection to be within sight or prevent installing back to back with the transfer switch outside and overcurrent protection inside.

85. I found an installation with a 120-volt kitchen refrigerator and 120-volt washing machine on a 2- pole breaker. Is this a legal installation?

• Reference: 210.4(B)

• Answer: 210.4 Multiwire Branch Circuits

• Branch Circuit, Multiwire. A branch circuit that consists of two or more ungrounded conductors that have a voltage between them, and a grounded conductor that has equal volt- age between it and each ungrounded conductor of the circuit and that is connected to the neutral or grounded conductor of the system.

86. I ran a 2-inch PVC feeder underground. Where it came up out of the ground I used a 2-inch rigid metal elbow and then continued with 2-inch PVC up a wall to a junction box 10 feet above the floor. I just used the rigid metal elbow for physical protection where it came out of the slab. Am I required to ground this steel elbow?

Reference 250.86 and exception #3

Yes.

Unless the metal elbow is completely encased in at least 2” of concrete or buried so the upper most part is a minimum of 18” below grade, then the elbow must be bonded to the equipment grounding conductor. The allowance not to bond is based solely on the possibility of someone coming into contact with the metallic elbow when it might be energized from a fault. Note that from the question it appears the elbow come up through the slab. Also note the by virtue of being buried in the earth the elbow is “grounded” and the question is really if the elbow should be “bonded”.

87. Is it permissible to run non-metallic cable through kitchen cabinets at peninsulas and islands where it is not subject to damage or does it always have to be sleeved?

If the cable is properly installed and not subject to physical damage it would not need to be sleeved. Section 334.12 for "Uses Not Permitted" does not list this type of installation in one of its sub-sections. If the installation, is determined to be subject to physical damage it would need to be protected. Section 334.15 Exposed Work in Sub-Section 334.15(B) requires NM Cables subject to physical damage to be protected using a few different type of raceways, or other approved means. 

88. I have a large and very old campground in my area and the owner does not want to correct the problems or re-wire it. What code can I cite to get things corrected?

• Reference: NEC Annex H – NEC 80.9(B), NEC 90.3, NFPA 1-section 11.1.1.1, IFC section 605.1, or State & Local Codes

• Answer: The NEC Annex H can be used to require corrections if specifically adopted by the Jurisdiction. Note that the Annexes in the NEC are for informational purposes only (90.3). If Annex H is adopted, then 80.9(B) would be applicable to this installation. 80.9(B) allows the Authority Having Jurisdiction to require existing electrical installations to be repaired to be safe condition if the existing electrical wiring presents an imminent danger to the occupants. Most Jurisdictions, State, County or Local, have similar types of languages in their local Electrical Codes.

• NFPA 1 & IFC (Fire Codes) may also be applicable if adopted by the Jurisdiction.

89. I have an old overhead service that is attached to the side of the building in an alley. The riser goes down to a round, 60 ampere meter socket. In this bar they only have a 60 ampere range and main cutout box that does not seem to be overloaded, since the bar only has a few lights and the canned and bottled beer is in an old unit cooler with water and ice to keep it from getting too warm. The outside riser has faulted out and needs to be replaced. The computed load per NEC 220 is 50 amperes. DO they need to replace the whole thing with a new 100 ampere service, or can they just repair the 60?

90.2[A] references ‘installations’ in the scope of the NEC. As this is a ‘repair’, Check with local AHJ. In our State if it was compliant when it was installed, it can be repaired.

90. With the new changes in the 2014 code requiring GFCI for disposal receptacles located under the kitchen sink, are these receptacles generally accepted to be readily accessible?

Answer: I would say that it is likely the electrical inspector would not consider them to be readily accessible. However it would really depend on where the receptacle was located within the cabinet. For example if the receptacle was located just to side of the cabinet door near the front it would likely be readily accessible. I would not likely have to remove objects to access it at that location.

91. At an old cabinet shop business, they have a pole-mounted NEMA 1 type panelboard out in the weather and it is rusted badly. The owner says he will get it covered up and does not want to spend a lot of money to have a licensed electrician on the site to work on it. What does he need to do to make this right and can he do it, since he feels it is just a repair?

Answer: Clearly the equipment wasn’t installed correctly in the first place. This would be an AHJ call being that it is an existing installation. It is of my opinion this NEMA 1 panel should be replaced with a panel that rated for outdoors (3R rated).

92. A local electrician says he used a Square D panel in the garage with a 100 amp main breaker installed (because it's cheaper to buy them that way), and that it's okay if he protects the panel with a 60 amp breaker back at the main provided that all the wiring is correct. I say he’s not correct because a home owner buying this house is under the impression there is a 100 amp supply at the detached garage. Who is right?

Reference: NEC 225.39

Answer: The inspector is always right BUT in this case possibly looking at the installation incorrectly. The feeder begins at the house so assuming that the circuit overcurrent and conductors are sized correctly and that the panel in the garage is SUSE rated and installed per NEC 225, the code requirements are met.

93. We are installing a transformer vault in a large apartment building. The vault will be venting into an areaway made of concrete with a large metal grate over the opening. The inspector says we can’t do that. What is wrong with this installation?

Reference: Webster’s Online Dictionary, 450.41, 450.42 & 450.45

Areaway - a sunken space affording access, air, and light to a basement

450.41 provides the requirement for vaults to be located where they can be ventilated to the outside air without using flues or ducts wherever such an arrangement is practicable.

450.42 requires the vault have approved structural strength for the conditions with a minimum fire resistance of 3 hours.

450.45 includes the requirements for ventilation openings. 450.45(E) requires all ventilation openings to the indoors shall be provided with automatic closing fire dampers that operate in response to a vault fire. Such dampers shall possess a standard fire rating of not less than 11⁄2 hours.

94. We are installing string lights in the entrance and lobby areas of a 14,000 seat auditorium. The inspector rejected the job saying the website says these are festoon lights. They are listed and the engineer says that if they are approved outdoors, they are ok for indoor use. Who is right?

• Reference: Reference: Article 590, 110.3(B),, UL White Book DGZZ, Pg. 116 and XBRT, pg. 549.

• UL does not have a category for Festoon lighting and UL 1598, the Standard for Luminaires does not permit cord or cable strung lights. These types of string lights are typically cover by UL under one of two categories Decorative Lighting Strings (DGZZ) located on page 116 in the 2014 UL White Book. The guide Information for DGZZ indicates that this is seasonal lighting strings such as Christmas lights intended seasonal

or temporary use not to exceed 90 days per year. The other category would be Temporary Lighting Strings, (XBRT) located on page 549 in the 2014 UL White Book. The guide information for XBRT states they are intended for use indoors and outdoors to provide temporary illumination in accordance with Article 590 of ANSI/NFPA 70, "National Electrical Code." From what I understand this product wasn't certified by UL, so we cannot speak for the other test lab.

 

• As for indoor and outdoor use, UL certified/Listed luminaires that are listed for use outdoors are also suitable for indoors. The general rule is all products are listed for indoor dry non-hazardous locations and if additional ratings are needed, such as outdoor then that is added. If the luminaire was for some reason found to be suitable only for outdoor use, then there would be a marking on the product with that limitation

95. The central vacuum system installer installed a suction outlet in a kitchen at an existing house. The vacuum outlet was adjacent to a kitchen wall receptacle. The circuit he tapped his five foot whip to was one of the 20 amp small appliance branch circuits. When he was told that he can’t tap off of this circuit, he said that the 30 foot vacuum cleaner hose is also serving the kitchen, so this is OK…..is this OK?

Section 210.52(B)(1) requires the two or more 20 ampere circuits to feed all receptacles in kitchen to be connected to the small appliance branch circuits. (B)(2) states that the two or more small-appliance branch circuits specified in 210.52(B)(1) shall have no other outlets. The connection of the vacuum hose connection is for power to the beater brush of the vacuum and should not be on the small appliance circuit.No, 210.52(B)(1) and (2) 

96. Would a cord- connected projector be allowed in an attic of a church above the drywall ceiling? Attic is accessible from a walkway.

• Reference: NEC 400.7(A)(6), 400.7(A)(8), 400.8

• Answer: Yes, the installation would most likely be allowed. NEC 400.7(A)(6) allows cords for utilization equipment for frequent interchange, 400.7(A)(8) allows cords where appliances are installed and the cord is for the ready removal for maintenance and repair. NEC 400.8 (uses not permitted) does not prohibit this specific installation. If the cord was installed thru the drywall ceiling, then 400.8(2) would prohibit this, as well as 400.8(5) would prohibit the cord from being installed in a concealed location. This specific installation has the cord installed within the accessible attic, therefore it appears to be

visible, accessible and not concealed and therefore can be inspected periodically for possible damage.

97. I have a local food vendor with a portable trailer which has been wired by the owner of the food business and they use a portable generator to supply power for the 120 volt receptacles and lights. The generator is set away from the trailer and a flexible cord is used to connect power to the trailer. Are there any special grounding requirements to properly ground the metal frame and metal siding of this trailer, and are ground rods required whenever this trailer is used at different events?

First part, is to determine what type of trailer you have.

Grounding the frame/siding not looked at because 90.2[B]1 states not covered since it is not mobile home or recreational vehicle also not a building or structure as described in 250.32. It is not used for temporary living quarters as scope for in 551 where it would require the frame and siding to be connected to the panelboard such as in 551.56B. If it is a 590 Temporary Installation feeder cords would have to be hard/extra hard usage type as stated in 590.4B

Second part, 250.34[A] states Connection to the GEC not required if using the receptacles ON the Portable Generator AND the equipment grounding conductor terminal of those receptacles are connected to the generator frame. And part [B] for Vehicle Mounted Generators is the same but adds that the generator also needs to be bonded to the vehicle frame.

98. The 2014 NEC requires a separate branch circuit to supply receptacles in dwelling unit garages. Can lighting outlets in the garage be installed on this circuit? Is a lighting outlet for a personnel door of the garage considered to be outside the garage since the wiring and junction box are located in the garage?

Answer: To the first question; yes as currently written lighting outlets within the garage could be installed on the same circuit.

There is no doubt this section is all about receptacle outlets. However, technically, the current wording permits other outlets to be on the same circuit.

To the second question; no an outlet for an outdoor luminaire would not be permitted on a circuit installed under 210.52(G)(1).

99. What are the working clearances requirements for a fire alarm control panel? Does Section 110.26 apply?

Answer: Yes

110.26 Spaces About Electrical Equipment. Access andworking space shall be provided and maintained about allelectrical equipment to permit ready and safe operation andmaintenance of such equipment.

(A) Working Space. Working space for equipment operatingat 600 volts, nominal, or less to ground and likely torequire examination, adjustment, servicing, or maintenancewhile energized shall comply with the dimensions of110.26(A)(1), (A)(2), and (A)(3) or as required or permittedelsewhere in this Code.

100. I need to relocate an emergency feeder due to expansion of a large assembly occupancy. The feeder was not required to be fire-rated at the original time of construction. Does the relocated feeder have to be a FHIT rated system or are we grandfathered in?

Reference: NEC 518.3(C), 700.10(D)

Answer: This installation would not be grandfathered. Assembly occupancies are covered in Article 518. 518.3(C) states the emergency system is covered in Article 700. If this is covered by 700.10(D) exceeds 1000 persons or is over 75 feet in height, then feeder circuit must meet one of the requirements in 700.10(D)(1) 1 through 5.

(1) Be installed in spaces or areas that are fully protected by an approved automatic fire suppression system

(2) Be a listed electrical circuit protective system with a minimum 2-hour fire rating

Informational Note: UL guide information for electrical circuit protective systems (FHIT) contains information on proper installation requirements to maintain the fire rating.

(3) Be protected by a listed thermal barrier system for electrical system components with a minimum 2-hour fire rating

(4) Be protected by a listed fire-rated assembly that has a minimum fire rating of 2 hours and contains only emergency wiring circuits.

(5) Be encased in a minimum of 50 mm (2 in.) of concrete

101. I am wiring a home in which a cabinet has been installed in a bathroom and the cabinet has been prewired with a receptacle inside one of the pull out drawers. Does this receptacle count for the receptacle required by the NEC for the bathroom sink?

Reference: 210.52 & 210.52(D)

Answer: 210.52 Dwelling Unit Receptacle Outlets

This section provides requirements for 125-volt, 15- and 20-ampere receptacle outlets. The receptacles required by this section shall be in addition to any receptacle that is:

(3) Located within cabinets or cupboards…

210.52(D) requires at least one receptacle outlet shall be installed in bathrooms within 3 ft of the outside edge of each basin.

102. I have a LED trim with the LED driver which is listed to either fit into a recessed can light housing or is acceptable to be installed into a 4” box. If I install this trim and driver into a 4” box in a clothes closet, will this be considered as a recessed luminaire or a surface mounted luminarie for clearances as described in 410.16(C)?

Reference 410.16(C)(1) and (C)(3)

If the 4” box is inside the wall or ceiling finish (flush mounted) then the LED installation should be considered as a recessed installation. If the 4” box is surface mounted then the installation would all be considered surface mounted. It would appear from the statement in the question that this assembly could be either surface or recessed mounted if the installation instructions on how to do the installation are followed

103. Can a meter base be closer than 3 ft. to a window? Our Utility says the meter base must be three feet from a window. I cannot find it in the code.

The electric utility company may have additional requirements for electrical installations above the requirements we have in the National Electrical Code. I believe the utility my be taking a NEC requirement and are creating their own rule. The NEC section 230.9 states: (A) Clearances. Service conductors installed as open conductors or multi-conductor cable without an overall outer jacket shall have a clearance of not less than 900 mm (3 ft.) from windows that are designed to be opened, doors, porches, balconies, ladders, stairs, fire escapes, or similar locations. Article 312 covers cabinets, cutout boxes and meter socket enclosures and there is no reference to windows in that article. Yes it can be closer to the window per the National Electrical Code, but the utility company may not connect to it, if it violates their rules.        

104. I have been told in the past that the fire alarm control panel (FACP) power supply is considered by the AHJ as an “emergency circuit”. Therefore this power supply to the FACP (with back up battery) must be installed per NEC 700.10(B) and be wired in a wiring methods allowed in that article. Is this true? I would like to install nonmetallic sheathed cable to supply power to the FACP, but the local AHJ insists this must be in a raceway or MC cable

References: NEC 700.2, 700.12(A) NFPA 72-10.6.3.2, 10.6.5, 10.6.7, IFC 604.2.16.2

Answer: Primary power supply allowed to be supplied from normal power panelboard, a secondary power supply (typically a battery) also required for FACP. NM cable would be acceptable provided battery was part of listed FACP. The power supply to the fire alarm panel(FACP) is required to be supplied from an emergency system,  the battery which is typically included with the FACP, is allowed by NEC 700.12(A), and is considered an emergency power system, therefore the branch circuit is not required to be supplied from an emergency system, such as a generator for the primary power supply. NFPA 72 has requirements for a primary and secondary power supply, and the IFC requires the fire alarm system be supplied from an emergency system. This installation is similar to the exit light with the battery installed within the exit light, the branch circuit supplying the exit light can be supplied by nonmetallic sheathed cable or any Chapter 3 wiring method provided the battery is located within the exit light.

105. We plan on using Milbank recreation vehicle pedestals for the expansion to an RV park. Each pedestal has a 50, 30, and 20 amperes breaker mounted on a feed-thru buss. Is each pedestal considered a “separate structure” and does each require connection to ground rods?

• Article 551 for the Parks have no requirement for this and prohibit the connection of a GEC to the Grounded Conductor except at the service. In 250.32 it references Buildings or Structures where in 100 Definitions it states a Building is a Structure that stands alone and A Structure is “That which is built or constructed”. A check with the local Building Inspector would show this pedestal does NOT require a building permit as it is not built or constructed for habitation, of course always check with the local AHJ.

106. Many homes in my jurisdiction still have Knob & Tube wiring in use in all or part of the home. I was called to look at an attic roof problem and noted that a local insulating company covered the old wiring up with insulation. The space is low and not easy to get into. When I called them they said they did their job and do not see it as a problem since it is done all the time and they will not do any more work on this house. I cited this as a violation, am I correct?

Answer: Section 394.12(5) prohibits concealed knob and tube wiring from being located in hollow spaces of walls, ceilings and attics that are insulated by loose, rolled or foam-in-place insulating material that envelopes the conductors.

The inspector was correct in citing the violation.

107. I have read about the photovoltaic systems now require AFCI protection. How do these devices work and where are they required to be installed within the PV system? On the roof, at the panels, or in the inverter? If installed within the inverter, how does the AFCI detect a fault ahead of the device?

Answer: DC PV arc fault protection is designed to detect and interrupt unintended arcs, in other words, the function must be able to differentiate intended arcs such as those which may be created by switching devices and unintended arcs such as those that may be created due to a break in a conductor. The Code does not specify where the function is to be located. It may be located somewhere in the system or in the inverter. Functionality currently on the market is located in inverters. If located within an inverter, the function is only able to interrupt series arcs, i.e. those in series with the inverter, not parallel arcs, i.e. those in parallel with the inverter. The function looks for characteristics in the arc signature that are unique to unintended arcing.

UL White Book QIDC (Photovoltaic DC Arc-fault Circuit Protection).

108. The lift pumps in the basement of an office building are located in sealed pits. The rigid conduit is specified to connect the sealed top of the pit to the controller cabinet. The power and control cords pass through about 8-feet of the rigid conduit to directly connect to the controller. Are cords permitted to run through conduit? How do I provide a seal or do I even need one?

Reference: NEC 400.8(6), 501.140(A)(3)&(B), 505.17

Answer: Answer: Yes, Yes. 400.8(6), 501.140(A)(3) & (B), 505.17 allows conduit to be used to protect and sleeve the cord for a pump like this. If the pit is considered a hazardous location, then a seal off in compliance with 501.15 would need to be used. If the pit is not a hazardous location, then a conduit seal that would prevent liquid or moisture from transferring out of the pit would be needed. This could be accomplished using duct seal. Check with the AHJ for a clarification. Code references 400.8(B); 501.140(A)(3) & (B)

109. The new single family home I just inspected has a NFPA 13D sprinkler system. The sprinklers are supplied with water through a couple of water tanks in the basement and a pump package. The pump package is factory wired enclosure that contains the pump, controller, flow and pressure switch and alarm module. Does this package need to meet Article 695? What is the

correct listing for the pump package? The manufacturer’s instructions indicated that it only needs to be connected to an individual branch circuit.

Reference: NEC 695.1 & NFPA 13D 6.2

695.1 Scope 2014 NEC Handbook: This article does not apply to pumps used to supply sprinkler systems in one- and two-family dwellings. NFPA 13D, Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes, does not require the use of a fire pump; thus, neither NFPA 20 nor Article 695 is applicable. NFPA 20 Stationary Fire Pump Handbook includes the same commentary.

In response to the second question, NFPA 13D section 6.2 addresses water supply sources

From the NFPA 13D & 13R Handbook: FAQ Where a pump is utilized, is it required to be in accordance with NFPA 20?

NFPA 13D does not require that a fire pump conforming to NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, be installed. The type of pump and the arrangement of power supplies to that pump only need to satisfy the system demand and must be electrically wired to conform to NFPA 70®, National Electrical Code®.

One of the key differences between 13D and 13 is that 13D uses the term “water pump” rather than “fire pump”. UL does list residential fire pump controllers but they are much different than a controller for a listed fire pump. The residential controllers are essentially just a pump motor controller and do not contain all of the time delay features relative to locked-rotor current.

Here is the information from the 2013 UL White Book (in part)

PUMP CONTROLLERS, FIRE, RESIDENTIAL (QZKE)

GENERAL

This category covers fire pump controllers intended for starting, stopping and protecting centrifugal fire pumps in one- and two-family dwellings and manufactured homes.

110. I have seen metal halide fixtures at some gas stations changed out to LED fixtures. Is it allowed to leave the 30 amp circuit breaker which supplied the previous metal halide fixtures with mogul base (heavy duty lampholders) installed for the new LED retrofit luminaires? It would appear 210.23(B) would not allow this 30 ampere circuit to remain in place for the retrofitted LED luminaires.

Reference 210.23(B)

Maybe.

The branch circuit overcurrent protection would need to be correct for the branch circuit conductors and also in accordance with the listing and installation instructions for the load. I will assume that with the HID luminaires the 30 Amp device was correct for the branch circuit conductors and luminaire assembly. Changing the luminaire to LED is now going to change the load and the branch circuit protection will need to be in accordance with whatever the limiting factor is. For LED lighting, unless listed for the 30 Amp branch circuit overcurrent device, would be required to be on a 15 or 20 amp branch circuit.

111. When changing a service from the house to the detached garage, how is the service on the detached garage to be grounded? How is the grounding handled at the house where this will now be a subpanel? The home has a copper water line supplying water to the home.

The question does not state the distance between the house and the detached garage. Is the house and garage three feet apart, 40 feet, 100 feet or even further apart. For this question let’s say its more than 20 feet between structures. The new service at the garage would need to have a grounding electrode system in accordance with section 250.50. The feeder from the garage to the house would need to be installed in accordance with 250.32. The feeder installed from the garage to the house is required to include an equipment grounding conductor. The grounding electrode system at the house is required by 250.32(A). The water pipe grounding electrode along with a supplemental grounding electrode(s) would be required to be connected together to form the grounding electrode system. The neutral is bonded at the service only and is isolated at the panel at the house. The grounding electrode system at the house would be connected to the electrical panel and the equipment grounding conductor of the feeder to the building.

112. A refrigerated warehouse uses ammonia as the refrigerant. I have to install gas detection and purge ventilation in the compressor room. Can I connect the purge ventilation to the emergency generator? Do I need a separate transfer switch and distribution system?

• Reference: NEC 700.2, 700.5(D), ASHRAE 15-2010 section 8.12

• Answer: Yes, the ventilation system can be connected to the emergency generator. Yes, a separate transfer switch & distribution system is required. This ventilation system would not be classified as an “emergency system”. This room can be classified as Class 1, Division 2 without ventilation present.

• Ammonia is classified as a B2 refrigerant and is subject to the special requirements listed in ASRHAE 15, section 8.12 – assuming the quantity of ammonia determines that a refrigeration room is required, there are exceptions for ammonia within section 8.12.  If

the room is served by a ventilation system that operates continuously the electrical equipment in the room does not need to be Class 1 Div 2.  When a standard says “operates continuously” this is typically interpreted to mean the system needs to be served by standby power.

113. The plumber placed the sump pump directly beneath my panel. Can I access the panel by standing on the lid? It seems pretty strong.

• Normal 110.26 access would need to be provided. If the ‘lid’ in this case is flat so tripping is not an issue it may be ok, otherwise some sort of platform may be needed.

114. I have a rural house and shop building that is fed through the house service panel, but the shop has a separate phone company line into it. Since this is a feeder, do I have to provide an intersystem bonding point on the shop?

Yes, 250.94 requires an intersystem bonding termination be provided external to service or metering equipment enclosures and at the disconnecting means for any additional buildings or structures.

The requirements for a disconnecting means for additional buildings or other structures are located in 225.31.

115. I would like to use PVC conduit to directional- bore some new feeders under a concrete yard. The conduit comes on a reel and is softer than conventional PVC. Do I need special fittings to connect it to the enclosures on each end? Can I use it above ground or do I need to transition to conventional PVC on each end?

Answer: Yes. HDPE is intended for underground use. There are listed HDPE fittings that transition to PVC Conduit. Just be careful, there are HDPE raceways and fittings that are used in the telecommunication world but are not listed.

116. The NEC defines a Panelboard, but has no definition for a Load Center. Can you explain the differences with this equipment?

Reference: NEC 408

Answer: A load center is a panelboard and required to be installed in accordance with Article 408. It is tested in accordance with UL 67, Category Code QEUY, the same as a panelboard.

117. I installed a condensate pump for a split system installed above a suspended ceiling. The inspector says I can’t put the receptacle above a suspended ceiling. How do I make this a legal installation?

• Reference: 400.7(A)(8) & 400.8(5)

• Answer: Flexible cords and cables are not limited to use with portable equipment. However, 400.8 prohibits the use of flexible cords and cables as a substitute for the fixed wiring of a structure or where concealed behind building walls, floors, or ceilings (including structural, suspended, or dropped-type ceilings).

• ROP 6-102 & 103/ROC 6-72 for the 2014 revision cycle

proposed permission-CMP 6 did not accept.

118. When doing a residential service most guys I know bury the grounding electrode conductor, extending outside the home to a ground rod, about the depth of a standard shovel spade head. Nobody can find a reference in Art.250 that clearly states the depth for a single grounding electrode conductor to be buried. Can you give a code reference for this depth? Table 300.5 col. 1 seems a bit excessive to most people.

Reference 250.64(B)

A change to the 2014 NEC in this section makes it clear that Table 300.5 does not apply for burial depth of a grounding electrode conductor. There is no minimum burial depth and all that is required is providing physical protection relative to the degree of physical damage that may occur. The main reason for not requiring the 300.5 burial depth is that digging into a grounding electrode conductor does not pose a shock hazard and also for lightning aspects sharp bends in the conductor are not desired.

119. Are remote -controlled light switches allowed in dwelling units, bedrooms and other habitable rooms? The switches being installed are battery operated with a control device mounted up within the ceiling light box, therefore the battery operated switch could easily be removed.

The requirements for lighting outlets in dwelling unit habitable rooms are located in 210.70(A)(1). Habitable Rooms. At least one wall switch-controlled lighting outlet shall be installed in every habitable room and bathroom. Exception No. 2: Lighting outlets shall be permitted to be

controlled by occupancy sensors that are (1) in addition to wall switches or (2) located at a customary wall switch location and equipped with a manual override that will allow the sensor to function as a wall switch.The type of remote control device referenced in the question was not found on the Internet. Section 110.3(B) would require the manufacturer’s installation instructions to be followed. Those instructions are required as part of the listing investigation and would need to be followed. Having the control device mounted up within the ceiling light box, draws a huge concern about having a compliant installation.

120. Our county fairgrounds is proposing sites for park trailers for the annual horse show. Do you see any reason we can’t feed 4 sites from one pedestal? Assuming the pedestal has (4) 30A and (4) 20A GFI receptacles on it. I don’t see any kind of spacing requirement in the code.

• Reference: NEC 551.71, 551.77 (A), (B), (C) & (E),

• Answer: Article 552 applies to wiring of the park trailers(see 552.1 scope), Article 551, Part IV has the requirements for the wiring of the parks where these units are used. There is no reason 4 sites cannot be supplied from one pedestal. There are some requirements for locating the receptacles on each site.

• 551.71 has the requirements for the minimum number & type of receptacles which are required to be installed in the park.

• 551.77(A) has the specific requirements for the location of the receptacles on each site depending if the site is a back in or drive thru site.

• The meter pedestal (possibly centrally located) would typically contain the circuit breakers adequately sized for the feeder conductors which would then supply the receptacles, typically contained within a listed pedestal on each park site with the required disconnects or circuit breakers, required by 551.77(B) at each site to disconnect power to the RV thru receptacles at the individual RV sites.

• 551.77(C) requires the site supply equipment be accessible and an unobstructed entrance or passageway a minimum of 2’ wide and 6’6” tall above the ground. 551.77(E) also requires the typical working space in accordance with 110.26.

121. Is a receptacle needed at all windows in a commercial building?

No. 210.62 would only require the single standard receptacle to be within 18” of the top for each 12 linear foot of a Show Window designed to be used for display of goods or advertising.

122. Is GFCI protection for personnel required for sump pumps and sewage ejector pumps located outdoors as part of an installation at a dwelling? Some inspectors say GFCI protection is not required because of possible nuisance tripping and the damage such an incident could pose. Section 210.8(A) requires GFCI protection for personnel for all 125-volt, single-phase, 15- and 20-ampere receptacles in location specified in (1) through (8). This includes (3) for Outdoors. Does the NEC require GFCI protection for receptacles (for cord-and-plug connected pumps) or for breakers serving sump pumps and sewage ejector pumps located Outdoors?

Answer: there are no specific requirements in the NEC for GFCI protection for sewage ejection or sump pumps so “hard wired” pump motors would not require GFCI protection by 210.8(A)(3).

As the submitter noted, the GFCI protection requirement is for 15 or 20 ampere, 125 volt, receptacles installed outdoors

123. The owner’s manual for a treadmill states the machines are to be pluggedinto a non -GFI circuit. I did not check all of the manuals, but the samewas true for a recent service issue we were called to. The treadmillthis person purchased tripped the ground fault breaker installed. Wetried changing the breaker to a standard breaker with a GFCI receptacle, and it still trips. Does the specification in the owner's manual override the code? This is the third instance of either a GFCI or Arc fault tripping for treadmills, all in different municipalities. In each case, customers have contacted the manufacturer and in each casethey were told to plug into non GFCI and non AFCI circuits. I am fairlycertain in each case, there are cords run to that type of circuit.

Answer: GFCI - The applicable UL standard is UL 1647 Motor-Operated Massage and Exercise Machines. The standard states that the leakage current for a portable machine may not exceed 0.5 mA and for a fixed machine 0.75 mA. If the machine meets the standard it should not cause a GFCI to trip. The GFCI tripping was probably caused by the variable speed motor drive.

AFCI - In order to address unwanted tripping with treadmills fed from AFCIs, the standard was revised a few years ago to add Electro Magnetic Compatibility (EMC) requirements. Whether this has reduced the unwanted tripping of AFCIs, whether mfgrs actually improved their designs is an another issue. Hopefully, the testing agency verifies this change in the standard.

124. I’m installing a whole house generator with an automatic transfer switch which is service rated which makes the exiting service panel a sub-panel. I understand that I need to separate the grounding conductors from the grounded conductors in the now-subpanel. However, this house

was wired when you were only required to use a three conductor type cable. Do I need to change this cable to a four wire type cable and change the dryer receptacle to a four wire?

Reference: NEC 215.6, 250.140 Exception, 250.142 Exception No.1

NEC 250.130(A), 250.134(A)

Answer: Yes. No. The conductors from the transfer switch to the subpanel are considered feeder conductors and based on 215.6 need to include a grounded conductor and a equipment grounding conductor. Since no changes are being made to the circuit s from the subpanel the NEC does not require updating these but it is a good idea. Don’t forget to remove the main bonding jumper in the subpanel and move the GEC to the transfer switch.

125. We have a 7.2kw car charging station for our EV. It indicates that a 2- pole 40 amp breaker is needed with #8 AWG conductors. In the instructions (since I only have a 100 ampere service on my house) it says we are permitted to “dial down” the amperage to 15 or 20 amperes if our service is not adequate. Can I install a 15 or 20 amp circuit to this car charger?

• Reference: 625.41 & 110.3(B)

• Answer: Installation in accordance with the manufacturer's instructions per 110.3(B) is required. If the charger can be dialed down to a smaller amperage, then you can reduce the calculation on the service,. However, it must still meet the requirements of the manufacturer’s installation instructions.

126. The inspector red-tagged my raintight in use cover. The manufacturer says I can mount it sideways without having the hinge on the top. Who is correct?

Reference 110.3(B)

Depends - The listing and installation instructions will specify how the in-use cover can be mounted. There are models that are listed to have the hinge on the top or to be mounted with the hinge to the left or right as the installation conditions require. If as the question states the manufacturers listing and installation instructions state it can be mounted “sideways”, then that is permitted.

127. I need to supply a building built on piers. The meter cabinet is on the outside. I plan to run conduit under the floor deck to the electrical room in the center of the building. Do I need Service Equipment at the meter location? The architect plans to enclose the piers with permanently mounted panels with a stucco-like finish.

The service disconnecting means would need to be installed in accordance with section 230.70. 230.70(A)(1) Readily Accessible Location. The service disconnecting means shall be installed

at a readily accessible location either outside of a building or structure or inside nearest the point of entrance of the service conductors.The question is would a conduit installed under the floor deck that will be concealed by the finish building materials be considered outside the building. Conductors are considered outside the building when they are installed in accordance with section 230.6. The installation as described would not be considered outside the building and a service disconnect outside the building would be required. The Answer is NO you do not have to install the service equipment at the meter location. The service disconnecting means will need to comply with 230.70.