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April 2009 NABCEP StudyGuide Questions 1-29SolPowerPeople, Inc.

Austin, TX

March 8, 2012

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Problem 1

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Problem 1

- 1. b. as required by OSHA Subpart E.- Seems to be an error in this answer. NABCEP indicates subpart

E. OSHA indicates subpart M.

- 1926.501(b)(1)- "Unprotected sides and edges." Each employee on a walking/working surface (horizontal and vertical surface)

with an unprotected side or edge which is 6 feet (1.8 m) or more above a lower level shall be protected from falling

by the use of guardrail systems, safety net systems, or personal fall arrest systems.

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Problem 1

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Problem 2

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Problem 2

- 2. b. reference OSHA Subpart E.

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Problem 3

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Problem 3

- 3. A. See section 3.1.2 (of NABCEP Study Guide)- The severity of the shock depends on the path of current

flow through the body, the amount of current, and the

duration of the exposure

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Problem 4

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Problem 4

- 4. A. See section 3.1.2 (of NABCEP Study Guide)- Currents above 10 mA can paralyze orfreeze muscles.

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Problem 5

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Problem 5

- 5. D. See section 3.1.2 (of NABCEP Study Guide)- Currents of more than 75 mA ac can cause a rapid,

ineffective heartbeat, and can result in death in minutes

unless a defibrillator is used.

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Problem 6

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Problem 6

- 6. A. See section 3.1.2

- Lockout and tagging is used to prevent unknowingindividuals from energizing electrical circuits while they are

being serviced or maintained.

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Problem 7

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Problem 7

- 7. B. See section 3.1.3 (of NABCEP Study Guide)- Consequently, OSHA requires that fall protection be used

for walkways and ramps, holes and excavations, roofs, and

wall openings where an employee or worker can fall 6 feet

or more.

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Problem 8

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Problem 8

- 8. D. See section 3.1.3 (of NABCEP Study Guide)- Guardrails used to protect open-sided floors and platforms

must have top rails between 39 and 45 inches tall, a mid rail,

and toeboards at least 3-1/2 inches high.

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Problem 9

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Problem 9

- 9. B. See section 3.1.3- Guardrails used to protect open-sided floors and platforms

must have top rails between 39 and 45 inches tall, a mid rail,

and toeboards at least 3-1/2 inches high.

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Problem 10

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Problem 10

- 10. D. See section 3.1.3- Safety nets must be deployed no further than 30 feet below

where work is performed, preferably closer.

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Problem 11

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Problem 11

- 11. C. See section 3.1.4- OSHA requires that a stairway or ladder be used at points

of access where there is an elevation break of 19 inches or

more on a jobsite.

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Problem 12

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Problem 12

- 12. A. See section 3.1.4- Stairways with four or more risers, or higher than 30

inches, must be equipped with at least one handrail, capable

of withstanding a force of 200 pounds.

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Problem 13

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Problem 13

- 13. B.See section 3.1.4

- Stairways with four or more risers, or higher than 30inches, must be equipped with at least one handrail, capable

of withstanding a force of200 pounds.

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Problem 14

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Problem 14

- 14. D. See section 3.1.4

- Stairs must be installed between 30 and 50 degrees, musthave uniform riser height and tread depth, with less than a

1/4-inch variation.

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Problem 15

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Problem 15

- 15. B. See section 3.1.4

- Stairways landings must be at least 30 inches deep and 22inches wide at every 12 feet or less of vertical rise.

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Problem 16

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Problem 16

- 16. B. See section 3.1.4-Non-self-supporting ladders (those that lean against a

wall or other support) must be positioned at an angle

where the horizontal distance from the top support to

the foot of the ladder is 1/4 the working length of the

ladder.

- The working height is 20 feet. 1/4th of 20 is 5 feet.

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Problem 17

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Problem 17

L = (12)2+ (3)

2+3

L = 144+ 9 +3

L = 153 +3

L =12.4+3

L =15.4feet

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Problem 17

12 feet

3 feet (i.e. of 12 as required byOSHA)

Unknownlength

3 feet as

required byOSHA

3.1.4 When using a portable ladder for access to anupper landing surface, the side rails must extend at least

3 feet above the upper landing surface.

L = (12)2+ (3)

2+3

L = 144+ 9 +3

L = 153 +3

L =12.4+3L =15.4feet

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Problem 18

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Problem 18

- 18. D. See section 3.1.4 If using ladders where theemployee or the ladder could contact exposed energizedelectrical equipment, such as transformers or overhead

services, ladders must have nonconductive side rails such as

wood or fiberglass.

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Problem 19

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Problem 19

- 19. D. See section 3.1.6- Class B hardhats are intended for electrical and utility

work, and protect against falling objects, as well as high-

voltage shock and burns. from NABCEP Study Guide.

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Problem 19

-WRONG!: Hard hats are classified based on ANSIZ89.1. The 1986 revision had a Class B classification for

high voltage. This classification changed in 1997 to

Classes G & E.

P bl 19

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Problem 19

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Problem 20

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Problem 20

- 20. D. See section 3.1.6 (of NABCEP Study Guide)- Employee responsibilities include using PPE in accordance

with training received and other instructions, and inspecting

daily and maintaining in a clean and reliable condition.

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Problem 21

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Problem 21

- 21. D. See section 3.1.6

- Eye protection must be provided to protect against hazards such as dust andother flying particles, corrosive gases, vapors, and liquids, and welding operations.

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Problem 22

Note: NABCEP loves this question!

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Problem 22

- 22. C.- C is the best answer because (a) is not at the level of the

workers, (b) may be distracted, and d is not at the level of

the workers and not in communication with them while

they work.

P bl 22

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Problem 22

"Safety monitoring systems." Safety monitoring systems [See 1926.501(b)(10) and 1926.502(k)] and their useshall comply with the following provisions:

1926.502(h)(1)

The employer shall designate a competent person to monitor the safety of other employees and the employer

shall ensure that the safety monitor complies with the following requirements:1926.502(h)(1)(i)

The safety monitor shall be competent to recognize fall hazards;

..1926.502(h)(1)(ii)1926.502(h)(1)(ii)

The safety monitor shall warn the employee when it appears that the employee is unaware of a fall hazard or is

acting in an unsafe manner;

1926.502(h)(1)(iii)

The safety monitor shall be on the same walking/working surface and within visual sighting distance of theemployee being monitored;

1926.502(h)(1)(iv)

The safety monitor shall be close enough to communicate orally with the employee; and

1926.502(h)(1)(v)The safety monitor shall not have other responsibilities which could take the monitor's attention from the

monitoring function.

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Problem 23

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Problem 23

- 23. B. The module and wiring can withstand short-circuitcurrent of the module, even if modules are connected inseries or parallel. (Wiring must be sized accordingly.)

P bl 23

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Problem 23- Consider this. Modules have a nameplate rating for Isc

(short-circuit current) under STC (standard test conditions)which is an irradiance of 1,000 watts per square meter

P bl 23

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Problem 23

- Now consider that allmodules have a series

fuse rating which is an

indication of the

ampacity of the device,

as in how much current

the device can handle.

P bl 23

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Problem 23

- This implies that inorder for the module

to produce current

greater than the

ampacity of the

module itself, it wouldbeen to be exposed to

an irradiance level of

3,200 watts per square

meter which you

would never see with

terrestrial irradiation.

Isc@1,000watts /m2= 6.25

20amps / 6.25amps = 3.2

3.21,000W /m2= 3,200W /m

2

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Problem 24

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Problem 24

- 24. C. Multiply the open-circuit voltage by 1.18. B- Be sure to use the 20C correction factor from NEC Table

690.7.

P bl 24

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Problem 24

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Problem 25

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Problem 25

- 25. B. The GFP is designed to provide fire protection. TheGFCI protects people from shock.

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Problem 25

-From 3.5.4.1: The 2008 NEC, in article690.5 requires that all grounded PV

arrays must incorporate a ground-fault

protection device to reduce fire hazards.

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Problem 26

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Problem 26

- 26. C. The module maximum power voltage decreases at therate of -0.5%/C (rule of thumb) for module temperaturesabove 25C.

-Hence, at 60C, the module voltage will have decreased by0.5(6025) = 17.5%, resulting in Vmp = 14.1 V.

Problem 27

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Problem 27

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Problem 27

- 27. A. SeeNEC 480.9(A). Note that option (c) represents animplementation of (a), but is not exact NEC wording.

Problem 27

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Problem 27

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Problem 28

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Problem 28

- 28. C.See instructions from equipment and batterymanufacturers.- When vented lead-acid batteries are used, they should not be located

beneath any electronic components. The corrosive vapors from the batteries

can degrade the circuitry in the electronic equipment causing prematurefailures.

- The answer implies all of the other battery types listed produced outgassingthat can damage electronic equipment.

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Problem 29

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Problem 29

- 29. B. See any instructions from manufacturers of storagebatteries or equipment that uses storage batteries.

- From section 3.1.9: If batteries are used outdoors in coldclimates, the electrolyte freezing temperature increases as the

batteries discharge. If the electrolyte freezes, DO NOT CHARGE

THE BATTERY. Let it thaw slowly in a place where, if it shouldrupture, the electrolyte will be contained. Do not attempt to

accelerate the thawing process with anything that might be

capable of igniting any gases that may be liberated.