V1k Motor Protection Filter KLC Series dv/dt Output Filters
Transcript of V1k Motor Protection Filter KLC Series dv/dt Output Filters
V1k Motor Protection Filter
KLC Series dv/dt Output Filters
V1k provides Motor Protection by limiting voltage spikes below 1,000 volts for long lead applications
Greatly extends the life of the motor and cable
Specific applications can reach 3,000 feet
30% reduction in common mode current
The V1k is the newest generation of the KLC dv/dt output filter series. V1kfilters are UL Listed and available in Open, Type 1 and Type 3R packagingconfigurations. The V1k supersedes the KLC product line.KLC to V1k part cross-reference is available.
Typical Problems, Superior Solutions with V1k
As Pulse Width Modulated (PWM) Drives are incorporated into various applications and processes, theincreased energy savings and decreased maintenance on Drives can be offset by increases in Motorfailures.
The KLC-Series V1k product family has been designed as an engineered solution for motor failures dueto the reflected wave phenomenon.
Reflective Wave Phenomenon
Voltage wave reflection is a function of the voltage rise time (dv/dt) and the length of the motor cables.
The impedance on either end of the cable run does not match, causing voltage pulses to be reflectedback in the direction from which it arrived. As these reflected waves encounter other waves, their valuesadd, causing higher peak voltage.
As wire length or carrier frequency increases, the overshoot peak voltage also increases.
Peak Voltages on a 460V system can reach 1200 to 1600V, causing rapid breakdown of motor insulation,leading to motor failure. On 575V systems, the peak voltages can easily reach 2100V. If this is leftuncontrolled, insulation failure may occur.
Mitigate Reflective Wave
By combining a patented dampening circuit with a low pass filter, V1k filters:
Increase the voltage rise time (dt out of dv/dt)
Prevent voltage spikes from exceeding 1,000 V
Slow pulse transitions, reduce dv/dt
Protect motor and cable insulation
Voltage without V1k Voltage with V1k
Reduces Common Mode Motor and Bearing Currents
Common Mode current, which leads to bearing pitting and bearing fluting, is reduced by a minimum of30%. V1k filters:
Slow down the pulse dv/dt by a factor of 3, reducing the harmful common mode currents
Increase bearing life and up-time
Reduce common mode noise and currents
Common Mode w/o V1k Common Mode with V1k
The V1K prevents voltage spikes from exceeding 1,000 V up to 2,000 feet and limits dv/dt to less than1,000 V/ μs. The product has been used successfully in applications up to 3,000 feet depending on cableand VFD sizes.
V1k Specifications
Ratings: 2 - 750 amps; 480 Volt; 7.5 - 600 HP
Carrier Frequency: 1 - 12 kHz
Fundamental Frequency: 0 - 60 Hz (consult factory for applications over 6 kHz and/or 60 - 120 Hzfundamental if the cable lengths don't exceed 400 feet)
Efficiency: > 98%
Insulation Rating: 600V Class
Insulation Class: Class H (180°C) or Class R (220°C)
Ambient Temperature: 40° C
Maximum Altitude: 2,000 meters (6,000 feet)
Derating necessary above 2,000 meters
Agency Approvals: cUL, UL
Enclosures: Open, UL Type 1, UL Type 3R
Lead Length: Specific applications can reach 3,000 feet (consult factory for applications above1,500 feet)
SCCR Version Available
V1k Typical Applications:
Oil and Gas Pumps
Irrigation Fields, Farms
Water, Wastewater
HVAC
Pulp, Paper
V1k dv/dt Performance Guarantee
Properly sized and applied, TCI guarantees that the V1k will limit motor terminal peak input voltage to150% of the bus voltage with a wire lead length of 1000 feet and a carrier frequency of 4 kHz. Maximumlead length and carrier frequency can vary depending on wire lead type. If a properly selected, installed,and loaded V1k filter fails to meet the guaranteed performance levels, TCI will provide the necessarycomponents or replacement filter at no additional charge. TCI does not take responsibility for additionalinstallation or removal costs, to include, but not limited to, replacement of third party equipment.
Minimum System Requirements for Guarantee
In order to achieve the performance levels as stated in this guarantee, the electrical system must adhereto the following: The V1K must be sized at no more than 110% of the drive output current rating. TheV1K must be sized to have regular line current loading of no less than 25% of its current rating. If theload has a potential for overhauling, the drive must be equipped with braking resistors or other features
limiting bus voltage to no more than the level of the peak line voltage. The V1K must be wired no morethan 10 feet from the drive.
V1k Installation
Guide
TCI, LLCW132 N10611 Grant Drive
Germantown, Wisconsin 53022Ph: 800-TCI-8282www.transcoil.com
Version 3.8 Part # 25316 March 21, 2014
TCI, LLCW132 N10611 Grant Drive
Germantown, Wisconsin 53022Ph: 800-TCI-8282www.transcoil.com
Field WiringField Wiring Connection TerminalsCompression type terminals are provided for all line wiring connections. The wire size capacity ranges and tightening torque for the power terminals are listed in the table.
Warnings and Cautions
Dangerous Voltage Warning: warns of situations in which a high voltage can cause injury and/or equipment damage. The text next to this symbol describes ways to avoid danger.
General Warning: warns of situations that can cause physical injury and/or equipment damage by means other than electrical. The text next to this symbol describes ways to avoid the danger.
General Safety Instructions
Be sure to read, understand, and follow all safety instructions.
Only qualified electricians should carry out all electrical installation and maintenance work on V1k drive output filters.
All wiring must be in accordance with the National Electrical Code (NEC) and/or any other codes that apply to the installation site.
Disconnect all power before working on the equipment. Do not attempt any work on a powered V1k output filter.
The V1k, VFD, motor, and other connected equipment must be properly grounded.
The VFD terminals and connected cables are at a dangerously high voltage when power is applied to the VFD, regardless of motor operation.
Warning
Warning
Warning
Warning
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Warning
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See www.transcoil.com for dimensions tables. Please contact TCI Technical Support or your TCI distributor for application information regarding the use of V1k output filters on the output side of the VFD.
V1k Model Numbers
Input and Output Motor Power
Wire Size Torque (in.-lb.)
V1k2A to V1k12A 12 - 14 10
V1k16A 4 - 12 20
V1k18A to V1k21A 4 - 10 20
V1k25A to V1k27A 4 - 8 20
V1k35A 6 - 8 30
V1k45A 6 30
V1k55A 1 - 4 35
V1k80A 1 - 3 35
V1k110A 2/0 - 1/0 50
V1k130A 2/0 50
V1k160A 250 MCM - 3/0 375
V1k200A two 2/0 - 1 50
V1k250A two 2/0 50
V1k305A 600 MCM - 3/0 500
V1k362A two 350 MCM - 4/0 375
V1k420A two 600 MCM - 300 500
V1k480A two 600 MCM - 350 500
V1k600A two 600 MCM - 500 MCM 500
V1k750A three 600 MCM - 400 MCM 500
All electrical connections must be re-torqued annually.
V1k KLC-Series Motor Protection Filter Installation Instructions
Installation Checklist• Make sure that the installation location will not be
exposed to direct sunlight, rain or dripping liquids, corrosive liquids or gases, explosive or combustible gases or dust, excessive airbourne dirt and dust, or excessive vibration.
• Select a mounting area that will allow adequate cooling air and maintenance access.
• Make sure that all wiring conforms to the requirements of the National Electric Code (NEC) and\or other applicable electrical codes.
• Ground the V1k Ouptut Filter to a dedicated system ground to ensure safety and filter performance. Use a properly sized grounding conductor.
• Wire the output power terminals of the VFD, T1(U), T2(V), & T3(W) to the input terminals of the V1k, A1, B1 & C1.
• Wire the output power terminals, of the V1k, A2, B2 & C2 to the motor power connections.
• Make sure the VFD is set for operating modes and ranges that are compatible with the V1k Output Filter.
• Check the entire system throughly before energizing and operating any equipment.
• Current Rating: 2 - 750 Amps, 240 V - 600 V, 7.5 - 600 HP
• cUL• Open, UL Type 1 and 3R Enclosures• Efficiency > 98% • Insulation Rating: 600V Class• Insulation Class: Class H (180°C or better)• Maximum Altitude: 2000 m (6,000 ft) Derating
necessary above 2000 m• Lead Length: Specific applications can reach
3,000 feet (consult factory for applications above 1,500 feet)
• Ambient Temp: Max 40°C
Product Specifications
Wiring Diagram
When you receive the unit, you should immediately inspect the shipping container and report any damage to the shipping carrier who delivered the unit.
Verify the ApplicationMake sure the V1k drive output filter is correct for the application. The current rating of the V1k should be sized to handle the FLA rating of the motor but not to exceed 110% of the drive output current rating. This output filter is best applied matched closely to the load. The V1k drive output filter is not selected by the drive input current rating. Properly sized and applied, TCI guarantees that the V1k will limit motor terminal peak input votage to 150% of the bus voltage with a wire lead length of 1000 feet and a carrier frequency of 4kHz. Maximum lead length and carrier frequency can vary depending on wire lead type. For best performance, the V1k should be installed within 10 feet of the drive.
Variable Frequency Drive SettingsMake sure that the variable frequency drive will be set for operation modes and ranges that are compatible with the V1k output filter: • Maximum output frequency: 60 Hz• PWM switching frequency best between 2kHz and
4kHz• Mode of operation: Do not use with DC braking unless
the drive application has been confirmed by TCI Technical Support
• Do not use on overhauling loads without bus voltage control.
Mounting and open panel unitIf you are mounting an open panel unit in your own enclosure, you must provide an enclosure that is adequately sized and ventilated sufficiently to prevent overheating. The filter is designed with a maximum ambient temperature of 40° C (104°F). If the ambient temperature exceeds this value it is the responsibility of the customer to provide auxiliary cooling to reduce the ambient operating temperature around the V1k filter. TCI strongly recommends using auxiliary cooling devices such as cooling fans, heat exchangers, or possibley air conditioning units when required to maintain the proper operating temperature.
The V1k must be mounted vertically on a smooth, solid surface, free from heat, dampness, and condensation. Mounting it verticallly is important for natural convection cooling. A metal plate is provided to mount the V1k on a composite surface.
Power WiringThe conduit and wiring from the output of the variable frequency drive to the motor must be routed to the V1k and then to the motor. TCI recommends a separate dedicated conduit run for each drive/filter/ motor run unless properly shielded and segregated wiring procedures are practiced. Parasitic and induced capacitance can greatly reduce the effectiveness of the filter performance. Under no circumstances should you wire both control and power wire in the same conduit unless the wire way is specifically designed for this practice. The line reactor temperature is sensitive to lead wire oversizing. Avoid lead wires more than five times oversized by copper cross sectional area regarldess of the material used. Use 75°C copper conductors only or the equivalent, unlesss the wire connector is marked for AI/Cu, then the use of aluminum wire is permitted. Use only copper conductor on units rated above 80 amps.
Wiring Cable Entry LocationsTCI has provided enclosure knock-outs on the two smaller enclosures for incoming and outgoing power cables. These are located in a typical wiring location for customer convenience. On the two larger size enclosures, TCI has not provided knock-outs due to the wide variety of application requirements. TCI allows installing electricians the option of locating the cable openings at a point of their choosing.
GroundingThe V1k filter must be connected to the ground of the premises wiring system. This can be conducted by identifying a known premises ground near by the filter or running a special ground dedicated for the application. The ground connection must be made using a wire conductor. Metallic conduit is not a suitable grounding conductor. The integrity of all ground connections should be periodically checked.
A1
B1
C1
B2
A2
C2
dv/dt MOTOR PROTECTION OUTPUT FILTER
V1k
Limits voltage spikes below 1,000 Volts for long lead applications
• Greatly extends the life of the motor and cable • Specific applications can reach 3,000 feet • 30% reduction in Common Mode Current
Line Reactors • Harmonic Filters • EMC Filters • dv/dt Filters • Sinewave Filters
dv/dt MOTOR PROTECTION OUTPUT FILTER
V1kTypical Problems, Superior Solutions with V1kAs Pulse Width Modulated (PWM) Drives are incorporated into
various applications and processes, the increased energy savings
and decreased maintenance on Drives can be offset by increases in
Motor failures.
The KLC-Series V1k product family has been designed as an
engineered solution for motor failures due to the reflected wave
phenomenon.
Reflective Wave Phenomenon
Voltage wave reflection is a function of the voltage rise time (dv/dt)
and the length of the motor cables.
The impedance on either end of the cable run does not match,
causing voltage pulses to be reflected back in the direction from
which it arrived. As these reflected waves encounter other waves,
their values add, causing higher peak voltage.
As wire length or carrier frequency increases, the overshoot peak
voltage also increases.
Peak Voltages on a 460V system can reach 1200 to 1600V, causing
rapid breakdown of motor insulation, leading to motor failure. On
575V systems, the peak voltages can easily reach 2100V. If this is left
uncontrolled, insulation failure may occur.
Mitigate Reflective Wave
By combining a patented dampening circuit with a low pass filter,
V1k filters:
• Increase the voltage rise time (dt out of dv/dt)
• Prevent voltage spikes from exceeding 1,000 V
• Slow pulse transitions, reduce dv/dt by a factor of 3 or more
• Protect motor and cable insulation
Reduces Common Mode Motor and Bearing Currents
Common Mode current, which lead to shaft voltages, bearing pitting,
and bearing fluting is reduced by a minimum of 30%. V1k filters:
• Slow down the pulse dv/dt by a factor of 3, reducing the harmful
common mode currents
• Increase bearing life and up-time
• Reduce common mode noise and currents
The V1K prevents voltage spikes from exceeding 1,000 V up to 2,000
feet and limits dv/dt to less than 1,000 V/ μs. The product has been
used successfully in applications up to 3,000 feet depending on
cable and VFD sizes.
Voltage Without V1k
Voltage With V1k
Common Mode Without V1k
Common Mode With V1k
1500
1000
-1500
-1000
-500
0
500
Volt
s
0 3530252015105
Time (ms)
1500
1000
-1500
-1000
-500
0
500
0 5 10 15 20 25 30 35
Vo
lts
Time (ms)
1.5
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-0.5
0 2 4 6 8 10 12 14 16 18 20
1
-1
0 2 4 6 8 10 12 14 16 18 20
Pe
r U
nit
Cu
rre
nt
Pe
r U
nit
Cu
rre
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Time (ms)
Time (ms)
1.5
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-0.5
1
-1
500 feet
500 feet
A1
B1
C1
B2
A2
C2
One Line Diagram of Patented Design
Part Numbering System
V1K 80 A01 EX
SeriesCurrent Rating (amps)Enclosure A00 = Open A01 = UL Type 1 A03 = UL Type 3ROption A EX = Heavy Duty Model
Properly sized and applied, TCI guarantees that the V1k will limit motor terminal peak input voltage to 150% of the bus voltage with a wire lead length of 1,000 feet and a carrier frequency of 4 kHz. Maximum lead length and carrier frequency can vary depending on wire lead type.
If a properly selected, installed and loaded V1k filter fails to meet the guaranteed performance levels, TCI will provide the necessary components or replacement filter at no additional charge.
TCI does not take responsibility for additional installation or removal costs to include but not limited to replacement of third party equipment. Please see TCI web site for minimum system requirements.
PERFORMANCE GUARANTEE
Product Specifications
• Ratings: 2 - 750 amps; 240 V - 600 V; 7.5 - 600 HP
• Carrier Frequency: 1 - 12 kHz
• Fundamental Frequency: 0 - 60 Hz (consult factory for applications over 8 kHz and/or 60 - 120 Hz fundamental if the cable lengths exceed 400 feet)
• Efficiency: > 98%
• Insulation Rating: 600V Class
• Insulation Class: Class H (180°C) or Class R (220°C)
• Ambient Temperature: 40° C
• Maximum Altitude: 2,000 meters (6,000 feet) Derating necessary above 2,000 meters
• Agency Approvals: cUL, UL
• Enclosures: Open, UL Type 1, UL Type 3R
• Lead Length: Specific applications can reach 3,000 feet (consult factory for applications above 1,500 feet)
• SCCR Version Available
• Operation possible up to 120 Hz output drive frequency with derating (contact factory for details)
Multiple Motor Applications
DRIVE
MOTOR
MOTOR
MOTOR
V1k
Please see web site for configuration guidelines.
TCI, LLCwww.transcoil.com
7878 North 86th StreetMilwaukee, WI 53224USA
Toll Free: 800-824-8282P: 414-357-4480F: 414-357-4484
Please contact us about specific products and services.
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1.4
V1k Typical Applications:
• Oil and Gas Pumps• Irrigation Fields, Farms• Water, Wastewater• HVAC• Pulp, Paper
KDR Line Reactor • Prevents nuisance tripping • Protects the source by lowering current distortion created by the drive
Additional Power Quality Solutions:
KMG Motor Protection Output Filter • Protects the motor by converting the PWM waveform into a near sinusoidal wave• Prevents voltage overshoots that cause early degradation of insulation systems in
motors, transformers, and cables• Extends motor life by reducing operating temperature
H5 Active Harmonic Filter• Helps meet IEEE-519• Reduces harmonic distortion to less than 5% TDD at full load• Actively monitors the load current while returning the power factor to near unity
HG7 Passive Harmonic Filter • Helps meet IEEE-519• Reduces harmonic distortion to less than 7% TDD at full load• Improves power factor
KRF EMC Filter • Filter EMI/RFI noise caused by power switching devices• Meet FCC regulation 15, subpart 3• Prevents interference with automated lighting circuits, security cameras, and other critical
electronics
Line Reactors • Harmonic Filters • EMC Filters • dv/dt Filters • Sinewave Filters
TCI Product Drawings V1K Type 1 www.transcoil.com
PART NUMBERRATED
VOLTS
NEC HP
480V
NEC HP
600V
NEC HP
240VAMPS HEIGHT WIDTH DEPTH ENCL TYPE
TERM
TYPE
TERM
TORQUE
TORQUE
UM
WATTS
LOSSWEIGHT
V1K2A01 600 0.75 1 - 2 9 5.5 10 1 tb 10 LB-IN 75 11V1K3A01 600 1 - 1.5 2 0.5 3 9 5.5 10 1 TB 10 LB-IN 75 11V1K4A01 600 2 3 0.75 4 9 5.5 10 1 TB 10 LB-IN 75 11V1K6A01 600 3 - 1 - 1.5 6 9 5.5 10 1 TB 10 LB-IN 80 11V1K8A01 600 5 5 2 8 9 5.5 10 1 TB 10 LB-IN 90 11V1K12A01 600 7.5 10 3 12 9 5.5 10 1 TB 10 LB-IN 95 11V1K16A01 600 10 - 5 16 9 5.5 10 1 TB 20 LB-IN 95 15V1K18A01 600 10 15 - 18 9 5.5 10 1 TB 20 LB-IN 110 15V1K21A01 600 15 - - 21 9 5.5 10 1 TB 20 LB-IN 110 15V1K25A01 600 15 20 7.5 25 9 5.5 10 1 TB 20 LB-IN 110 15V1K27A01 600 20 25 - 27 9 5.5 10 1 TB 20 LB-IN 110 15V1K35A01 600 25 30 10 35 12 8 11.5 1 TB 30 LB-IN 130 23V1K45A01 600 30 40 15 45 12 8 11.5 1 TB 30 LB-IN 135 23V1K55A01 600 40 50 20 55 12 8 11.5 1 TB 35 LB-IN 145 23V1K80A01 600 50 - 60 75 25 - 30 80 12 8 11.5 1 TB 35 LB-IN 255 29V1K110A01 600 75 100 40 110 16.5 18 15 1 PT 50 LB-IN 245 68V1K130A01 600 100 125 50 130 16.5 18 15 1 PT 50 LB-IN 270 83V1K160A01 600 125 150 60 160 16.5 18 15 1 PT 375 LB-IN 260 83V1K200A01 600 150 200 75 200 16.5 18 15 1 PT 50 LB-IN 265 93V1K250A01 600 200 250 100 250 16.5 18 15 1 PT 50 LB-IN 290 93V1K305A01 600 250 300 - 305 16.5 18 30 1 PT 500 LB-IN 325 117V1K362A01 600 300 350 150 362 16.5 18 30 1 PT 375 LB-IN 300 117V1K420A01 600 350 450 - 420 16.5 18 30 1 PT 500 LB-IN 450 132V1K480A01 600 400 500 200 480 16.5 18 30 1 PT 500 LB-IN 475 138V1K600A01 600 500 600 - 600 16.5 18 30 1 PT 500 LB-IN 515 168V1K750A01 600 600 700 - 750 16.5 18 30 1 PT 500 LB-IN 770 180
Page 1 of 1
dV/dTGUARD V1k MOTOR-PROTECTING PWM OUTPUT FILTER
SAMPLE BIDDING SPECIFICATIONS
Page 1 of 2
1.0 GENERAL
1.1 The V1k dampened low pass filter, (hereafter also known as "dV/dTGuard" or "PWM Output Filter"), minimizes motor failures due to IGBT-based drives that are connected by long leads. Motors controlled by variable frequency drives that are installed some distance away often fail as a result of high voltage-induced insulation breakdown. The extremely fast switching time of the IGBT drive is reflected by the steep edges (dV/dT’s) of the PWM voltage waveform. When uncontrolled, these high dV/dT’s result in voltage wave reflections which can become additive at the pulse level yielding a voltage overshoots or spikes. These voltage overshoots damage the motor and cable insulation and lead to motor failure as the length of the motor cables increase. The combined inductance, capacitance and resistance of the PWM Output Filter shall be specifically designed to reduce voltage waveform dV/dT. In so doing, the dV/dTGuard shall also minimize parasitic resonance interaction between the inductive and the capacitive elements within the long leads. Left unguarded, this conductor resonance phenomenon would likewise contribute to the formation of motor-damaging voltage spikes.
1.2 The V1k dampened, low pass filter consists of a gapped, three phase, iron core inductor; AC-rated, polypropylene capacitors; and wire-wound resistors. The filter shall be rated for application at a maximum fundamental system frequency of 60Hz at nominal system voltages up to 600V. The filter shall operate at a maximum carrier frequency of 8kHz at 40% of fundamental voltage. The ambient temperature of operation shall be 40°C. The maximum distance from the drive to the input terminals of the V1k filter shall be 20 ft. V1k filter application shall be effective for lead distances between the drive and the motor that range from 50 ft. to 3,000 ft., depending on the application details (consult factory). Leads should not be electrically oversized more than four cable sizes or the mechanical limitations of the cable connectors.
2.0 COMPONENTS
2.1 INDUCTORS
2.1.1 The three phase inductors shall be designed for harmonic filtering service and for slowing the rate of rapid current changes. The inductors shall be UL component-recognized and shall be built to comply with UL 508A standard. Construction shall be of copper wire wound on magnetic grade steel. Inductors shall be sized appropriately for the total connected load. The design maximum temperature rise for reactors shall be 115° C or 155º C depending on frame size at rated current.
2.1.2 The core shall be made of laminated, electrical steel (grade M50 or better).
2.1.3 Brackets shall be ASTM structural steel or structural aluminum. Coils shall be wedged in place and the core shall be locked in place using vertical ties or rods.
2.1.4 Windings shall consist of copper wire or of copper foil. Terminations shall be copper alloy ring lugs, UL-recognized terminal blocks, or solid copper bus. Sheet insulation shall be Tufquin or Cequin IF or Dupont Nomex 410 of the thickness as required for UL insulation systems.
2.1.5 Inductors shall be air-gapped to control saturation. Inductance shall be measured under full load and shall be within 10% of design value.
dV/dTGUARD V1k MOTOR-PROTECTING PWM OUTPUT FILTER
SAMPLE BIDDING SPECIFICATIONS
Page 2 of 2
2.1.6 Completed inductors shall be impregnated with 100% solid epoxy resin. All insulation varnish systems shall be rated class R (220° C) or H (180°C), 600V.
2.1.7 Inductance shall remain above 50% of nominal for any overload up to 200% of rated current. Inductors shall not sustain any thermal damage for levels up to 150% of rated current for a minimum period of five minutes. Inductors shall be Hi-Pot tested (2,640V, 60 Hz, 1 second) line-to-line and line-to-ground.
2.2 CAPACITORS
2.2.1 Capacitors shall be constructed of metallized polypropylene film material.
2.2.2 Capacitors shall be Y(Wye)-connected and ungrounded neutral. Each capacitor element shall be rated at minimum of 700V AC.
2.3 RESISTORS
2.3.1 Resistors shall consist of wire-wound cement construction and incorporate thermal insulating terminations.
2.3.2 Resistors shall be derated to operate at twice the calculated worst case requirements for watts loss.
3.0 PROTECTION
3.1 Enclosure (optional) shall be designed to conform to NEMA 1 standards. Enclosure shall be constructed from steel with enamel finish. Enclosure openings shall be provided to allow for air flow convection cooling. Provisions shall be made to allow for permanent conduit entry sites. Enclosure shall have a removable cover that shall not at any time disrupt the conduit connections.
4.0 WARRANTY
4.1 The dV/dTGuard V1k output filter shall be warranted free from defects in both materials and in workmanship for a period of one year from the date of installation or for a maximum of two years from the date of purchase, whichever comes first.