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Eaton Guide SpecificationNotes and instructions to specwriter

The following guide specification is offered for your assistance in specifying this product as part of a CSI (Construction Specification Institute) compliant document.This guide specification has been created in MS Word and uses Word features including Styles and Review to assist in editing and formatting. You may also find it helpful to view the document in Outline mode when editing or selecting sections to copy/paste into your base document.

Styles Styles are provided for all paragraph types described in the CSI Masterformat. Applying a Style to text will provide the correct indentation, paragraph letter/number, font, capitalization, etc…. Styles are shown on the right-hand side of the Word “Home” ribbon.

Review“Notes to Specwriter” (when available) are provided using the Reviews feature in Word. To view “Notes to Specwriter” select “All Markup” in the Tracking dropdown menu on the Review ribbon. To hide notes, select “No Markup”. You can advance from one note to the next using the Previous and Next buttons on the same ribbon. In earlier versions of MSWord hide notes by un-checking ‘Comments’ under Review>SH

Outline view The Outline view within Word is often helpful when editing or copying sections from this Guide Specification. Also, when pasting sections from this document into a base document the specwriter may want to consider using right-click and “Merge Formatting’ or ‘Keep Text Only” features.

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SECTION 26 12 13.03LIQUID-FILLED, MEDIUM-VOLTAGE AR-VFI UNIT SUBSTATION TRANSFORMERS

PART 1 GENERAL

1.01 SCOPE

A. This specification applies to three-phase, 300–12,000 kVA, 50-60 Hz, fully dead front, unit substation transformers. Differential overcurrent protection shall be accomplished utilizing a 24VDC microprocessor-based differential relay paired with a resettable vacuum fault interrupter (VFI) which shall be provided with three-pole ganged operation. [The unit shall have a motor operator] [The unit shall have motor operator provisions] [the unit shall be manually operated].

B. The VFI unit is to be used for transformer differential protection & local/remote on/off switch

C. The unit is to be insulated with Envirotemp™ FR3™ less-flammable dielectric fluid. The unit shall utilize vacuum interrupters for all fault current interruption such that the dielectric media is not consumed or contaminated by normal operations of the interrupters. The unit shall be designed for installation on a concrete or fiberglass pad at ground level.

D. The transformer shall use resettable interrupter controls and shall not use expulsion fuses (use of PRCLFs for increased interrupt rating are allowable).

E. This specification shall only cover the purchase and shipment of transformers. The purchaser and/or user shall be responsible for all site-work, electrical connections, and installation.

1.02 APPLICABLE STANDARDS

A. All characteristics, definitions, and terminology, except as specifically covered in this specification, shall be in accordance with the latest revision of the following IEEE®, Department of Energy, and NEMA® standards.

1. IEEE Std C37.60™-2012 standard – IEEE Standard Requirements for Overhead, Pad-Mounted, Dry Vault, and Submersible Automatic Circuit Reclosers and Fault Interrupters for Alternating Current Systems Up to 38 kV

2. IEEE Std 386™-2016 standard – Standard for Separable Insulated Connector Systems for Power Distribution Systems Above 600 V.

3. IEEE Std C37.90™-2005 standard – IEEE Standard for Relays and Relay Systems Associated with Electric Power Apparatus.

4. IEEE Std C37.90.2™-2004 standard – Standard for Withstand Capability of Relay Systems to Radiated Electromagnetic Interference from Transceivers.

5. IEEE Std C57.12.00™ - 2015 standard – Standard for Standard General Requirements for Liquid-Immersed Distribution, Power, and Regulating Transformers.

6. IEEE Std C57.12.28™-2014 – Sections 5.3, 5.4, 5.5 – Coating System Requirements

7. IEEE Std C57.12.36™ - 2017 standard – IEEE Standard Requirements for Liquid-Immersed Distribution Substations Transformers – applicable when substation style transformer is specified

8. IEEE Std C57.12.90™ - 2011 standard – IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating Transformers and IEEE Guide for Short-Circuit Testing of Distribution and Power Transformers.

9. IEEE Std C57.12.91™ standard – Guide for Loading Mineral-Oil-Immersed Transformers.

10. IEEE Std C57.154™ standard – IEEE standard for the design, testing, and application of liquid-immersed distribution, power, and regulating transformers using high-temperature insulation systems and operating at elevated temperatures

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11. IEEE Std 1584™ - 2018 – IEEE Guide for performing arc-flash hazard calculations

12. NEMA TR 1-1993 (R2000) – Transformers, Regulators and Reactors, Table 0-2 Audible Sound Levels for Liquid-Immersed Power Transformers.

13. NEMA 260-1996 (2004) – Safety Labels for Pad-Mounted Switchgear and Transformers Sited in Public Areas.

14. 10 CFR Part 431 – Department of Energy – Energy Conservation Program for Commercial Equipment: Distribution Transformers Energy Conservation Standards; Final Rule.

PART 2 PRODUCTS

2.01 MANUFACTURERS

A. Eaton

B. __________

C. __________

2.02 RATINGS

A. The transformer shall be designed in accordance with this specification and the base kVA rating shall be:[300] [500] [750] [1000] [1500] [2000] [2500] [3000] [3750] [5000] [7500] [10000] [12000] kVA (Note: Write in kVA if different than listed standard selections)

B. The transformer shall have a high voltage and the basic lightning impulse insulation level (BIL) of ____ V and ____ kV BIL (For standard BIL transformers select HV and BIL ratings from Table 1 using the standard transformer column for BIL. For Critical load (CLT) or Hardened Datacenter (HDC) designs requiring higher BIL ratings select HV and BIL from table 1 using the CLT/HDC column for BIL. CLT/HDC designs require FR3 high fire point fluid)

C. The transformer shall have a dual high voltage to be reconnected with an externally operable, de-energized switch. The voltages provided and the basic lightning impulse insulation level (BIL) shall be _________ x________ V and ___ kV BIL (For standard BIL transformers select HV and BIL ratings from Table 1 using the standard transformer column for BIL. For Critical load (CLT) or Hardened Datacenter (HDC) designs requiring higher BIL ratings select HV and BIL from table 1 using the CLT/HDC column for BIL). Dual voltage HV ratings shall not exceed a 3:1 ratio. CLT/HDC designs require FR3 high fire point fluid)

D. The low voltage and the basic lightning impulse insulation level (BIL) shall be ________ V and __ kV BIL. (For standard BIL transformers select LV and BIL ratings from Table 1 using the standard transformer column for BIL. For Critical load (CLT) or Hardened Datacenter (HDC) designs requiring higher BIL ratings select LV and BIL from table 1 using the CLT/HDC column for BIL. CLT/HDC designs require FR3 high fire point fluid)

Table 1Transformer Ratings and Electrical

Characteristics

Transformer

Basic Impulse Insulation Level – BIL (kV)

Voltage Ratings (volts) Standard Transformers

CLT/HDC Transformers

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Secondary Voltages208Y/120480Y/277575Y/332600Y/347690Y/398240 Delta480 Delta240 Delta with 120 Mid-Tap480 Delta with 240 Mid-Tap

303030303030303030

454545454545454545

Primary Voltages 2400 Delta4160 Delta4800 Delta7200 Delta12000 Delta12470 Delta13200 Delta13800 Delta14400 Delta16340 Delta34500 Delta43800 Delta4160GrdY/24008320GrdY/480012470GrdY/720013200GrdY/762013800GrdY/797022860GrdY/1320023900GrdY/1380024940GrdY/1440034500GrdY/1992043800GrdY/25300

60606075959595959595150

-6075959595125125125150

-

959595951251251251251251252002509595125125125150150150200250

** Note to Specifier – The above table is not meant to list every voltage available.(note: CLT/HDC designs require FR3 high fire point fluid)

E. The high voltage and low voltage connections of the transformer shall be: (If a special connection is required it shall be requested on the inquiry.)

1. [] Delta - Wye:

a. For Delta - Wye configurations the low voltage neutral shall be a fully insulated X0 bushing. The low voltage shall lag the high voltage by 30°.

2. [] Delta - Grounded Wye

a. For Delta - Grounded Wye configurations the low voltage neutral shall be a fully insulated X0 bushing with ground strap. The low voltage shall lag the high voltage by 30°.

3. [] Delta - Delta

a. For Delta - Delta configurations the transformer shall be provided without a neutral bushing. There shall be no phase shift between the high voltage and low voltage.

4. [] Grounded Wye - Wye

a. For Grounded Wye - Wye configurations the high voltage neutral shall be internally tied to the low voltage neutral and brought out as the H0X0 bushing. There shall be no phase shift between the high voltage and low voltage.

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5. [] Wye - Grounded Wye

a. For Wye - Grounded Wye configurations the high voltage neutral shall be brought out as the Ho bushing on the high voltage side and the low voltage neutral shall be brought out as the X0 bushing with ground strap on the low voltage side. There shall be no phase shift between the high voltage and low voltage.

6. [] Wye - Delta

a. For Wye - Delta configurations the high voltage neutral shall be brought out as the Ho bushing on the high voltage side. The low voltage shall lag the high voltage by 30°.

F. The transformer shall be furnished with full capacity high-voltage taps. The tap-changer shall be clearly labeled to reflect that the transformer must be de-energized before operating the tap-changer as required in Section 4.3 of IEEE Std C57.12.34™-2009 standard. The tap-changer shall be operable on the higher voltage only for transformers with dual high voltages. The unit shall have one of the following tap configurations:

1. [] No Taps

2. [] Two – 2 ½% taps above and below rated voltage (split taps)

3. [] Four – 2 ½% taps below rated voltage (four below)

4. [] NEMA taps (14400, 13800, 13200, 12470, 12540)

5. [] Non-standard tap configuration: ___________________

G. The dielectric coolant shall be listed less-flammable fluid meeting the requirements of National Electrical Code® Section 450-23 and the requirements of the National Electrical Safety Code® (IEEE Std C2™-2002 standard), Section 15. The dielectric coolant shall be non-toxic*, non-bioaccumulating and be readily and completely biodegradable per EPA OPPTS 835.3100. The base fluid shall be 100% derived from edible seed oils and food grade performance enhancing additives. The fluid shall not require genetically altered seeds for its base oil. The fluid shall result in zero mortality when tested on trout fry *. The fluid shall be certified to comply with the US EPA Environmental Technology Verification (ETV) requirements and tested for compatibility with transformer components. The fluid shall be Factory Mutual Approved®, UL® Classified Dielectric Medium (UL-EOUV) and UL® Classified Transformer Fluid (UL-EOVK), Envirotemp™ FR3™ fluid.

*(Per OECD G.L. 203)

Note: The transformer can be supplied with mineral oil as the dielectric coolant. Replace the above statement with “Transformer will be supplied with mineral oil as the dielectric coolant.” If mineral oil is chosen, the following designs will not be available as they require FR3 high fire point fluid.

75°C, 65/75°C, and 55/75°C PEAK transformers HDC or CLT designs

H. The transformer, filled with Envirotemp™ FR3™ fluid, shall have a: (note: 75 rise designs require FR3 high fire point fluid)

1. [] 65°C average winding temperature rise rating. The above winding temperature rise shall not exceed 65°C when loaded at base kVA rating.

2. [] 75°C average winding temperature rise rating. The above winding temperature rise shall not exceed 75°C when loaded at base kVA rating. This transformer is identified as a PEAK transformer.

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3. [] 55/65°C average winding temperature rise rating. The above winding temperature rise shall not exceed 55°C when loaded at base kVA rating. The transformer shall provide an additional 12% continuous operating capacity at the 65°C rating.

4. [] 65/75°C average winding temperature rise rating. The above winding temperature rise shall not exceed 65°C when loaded at base kVA rating. The transformer shall provide an additional 12% continuous operating capacity at the 75°C rating. This transformer is identified as a PEAK transformer.

5. [] 55/75°C average winding temperature rise rating. The above winding temperature rise shall not exceed 55°C when loaded at base kVA rating. The transformer shall provide an additional 22% continuous operating capacity at the 75°C rating. This transformer is identified as a PEAK transformer.

I. The percent impedance voltage, as measured on the rated voltage connection, shall be per Table 5 of IEEE Std C57.12.36™-2017 standard.

J. The transformer shall be cooled by the natural circulation of air over the tank surface [and any corrugate or radiators if required, allowing only the base kVA rating shall be provided with Class KNAN.] [, with an additional rating obtained by forced air circulated over the radiators or corrugate. The unit shall be provided with KNAN/KNAF rated cooling including fans and control equipment. Control power shall be provided by others. Additional capacity ratings shall be as follows; 15% for 750-2,000 kVA, 25% for 2,500-10,000 kVA, 33% for 12,000 kVA.] [, with future kVA capacity built into the cooling surfaces and conductors. The unit shall be provided with KNAN/Future KNAF rated cooling. Additional capacity ratings shall be as follows; 15% for 750-2,000 kVA, 25% for 2,500-10,000 kVA, 33% for 12,000 kVA]

K. UL® Listing/Classification and FM® Approval

1. [] The transformer shall be UL® Listed (certifying compliance with IEEE® standards only) per UL® XPLH.

2. [] The transformer shall be combination UL® Listed & Classified to comply with NEC® 450-23 listing restrictions for installations on, near, or inside of buildings per UL® XPLH.

3. [] The transformer shall be FM® Global (FM) Approved to comply with NEC® 450-23 listing restrictions for installations on, near, or inside of buildings.

2.03 CONSTRUCTION

A. The core and coil shall be vacuum processed to ensure maximum penetration of insulating fluid into the coil insulation system. While under vacuum, the windings will be energized to heat the coils and drive out moisture, and the transformer will be filled with preheated filtered degassed insulating fluid. The core shall be manufactured from burr-free, grain-oriented silicon steel and shall be precisely stacked to eliminate gaps in the corner joints. The coil shall be insulated with B-stage, epoxy coated, diamond pattern, insulating paper, which shall be thermally cured under pressure to ensure proper bonding of conductor and paper.

B. [Panel type radiators or corrugate type cooling are welded directly to the tank when additional cooling is required.] [Panel type, removable radiators, complete with flanged shut off valves on the tank side shall be provided.]

C. The tank must be welded using precision cut, cold-rolled steel plate and equipped with extra-heavy duty, welded-in-place lifting lugs and jacking provisions. The tank base must be designed to allow skidding or rolling in any direction.

D. The transformer shall be of sealed tank construction of sufficient strength to withstand a pressure of 7 psig without permanent distortion, and 15 psig without rupturing.

E. The tank shall include a pressure relief device as a means to relieve pressure in excess of pressure resulting from normal operation. The venting and sealing characteristics shall be as follows:

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1. Cracking Pressure: 10 psig +/-2 psig

2. Resealing Pressure: 6-psig minimum

3. Zero leakage from reseal pressure to -8 psig

4. Flow at 15 psig: 50 SCFM minimum

F. The tank shall be cleaned with an alkaline cleaning agent to remove grease and oil. An iron phosphate coating shall then be chemically bonded to the metal to assure coating adhesion and retard corrosion. The tank shall be primed with an electrodeposited powder epoxy to provide a barrier against moisture, salt, and corrosives. The top-coat shall be a liquid polyurethane coating to seal and add ultraviolet protection. The tank coating shall meet all requirements in IEEE Std C57.12.28™-2014 standard.

G. The high voltage terminations shall each be [located on the cover.] [enclosed with the following:]

1. [] Throat

a. A throat is used on a transformer with sidewall-mounted bushings for connecting the transformer with bus duct. It extends 8 inches above and below the centerline of the bushings.

2. [] Flange (required with high voltage air disconnect switch)

a. A flange is used on a transformer with sidewall mounted bushings for direct connection to metal clad switchgear and is required with the high voltage air disconnect switch option. The flange extends 8 inches above and 32 inches below the bushing centerline.

3. [] Partial height, bottom entry air terminal chamber

a. The partial height bottom entry chamber extends approximately 24 inches below the centerline of the bushings and has a bottom removable plate that can accommodate cable glands or conduit hubs. The chamber shall include [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

4. [] Partial height, top entry air terminal chamber

a. The partial height top entry air terminal chamber has a chimney with a removable cover that extends 24 inches above the bushing centerline and can be equipped with cable glands or conduit hubs. Bus duct can be adapted to match the top of the chimney for bus termination. [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

5. [] Full height, bottom entry cabinet

a. A full height bottom entry air terminal chamber is a weather-resistant metal enclosure around sidewall mounted bushings that extends downward to the transformer base level and upward approximately 10 inches above the bushing centerline. It is intended for underground feed and is provided with facilities for distribution arresters. [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

6. [] Full height, top entry cabinet

a. A full height top entry air terminal chamber is a weather resistant metal enclosure around sidewall mounted bushings that extends downward to the transformer base level and upward approximately 24 inches above the centerline of the bushings. The chamber shall include [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

H. The low voltage terminations shall each be [located on the cover.] [enclosed with the following:]

1. [] Throat

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a. A throat is used on a transformer with sidewall-mounted bushings for connecting the transformer with bus duct. It extends 8 inches above and below the centerline of the bushings.

2. [] Flange

a. A flange is used on a transformer with sidewall mounted bushings for direct connection to metal clad switchgear and is required with the high voltage air disconnect switch option. The flange extends 8 inches above and 32 inches below the bushing centerline.

3. [] Partial height, bottom entry air terminal chamber

a. The partial height bottom entry chamber extends approximately 24 inches below the centerline of the bushings and has a bottom removable plate that can accommodate cable glands or conduit hubs. The chamber shall include [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

4. [] Partial height, top entry air terminal chamber

a. The partial height top entry air terminal chamber has a chimney with a removable cover that extends 24 inches above the bushing centerline and can be equipped with cable glands or conduit hubs. Bus duct can be adapted to match the top of the chimney for bus termination. [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

5. [] Full height, bottom entry cabinet

a. A full height bottom entry air terminal chamber is a weather-resistant metal enclosure around sidewall mounted bushings that extends downward to the transformer base level and upward approximately 10 inches above the bushing centerline. It is intended for underground feed and is provided with facilities for distribution arresters. [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

6. [] Full height, top entry cabinet

a. A full height top entry air terminal chamber is a weather resistant metal enclosure around sidewall mounted bushings that extends downward to the transformer base level and upward approximately 24 inches above the centerline of the bushings. The chamber shall include [a hinged door with padlockable handle and a [pentahead] [hexhead] bolt] [a lift-off front panel].

I. The tank shall be complete with an anodized aluminum laser engraved nameplate. This nameplate shall meet IEEE Std C57.12.00™-2010 standard for Nameplate B.

J. High voltage bushings and terminals

1. [] The transformer shall be provided with three (3) [sidewall] [cover] -mounted high voltage bushings plus a H0 neutral bushing for WYE connected transformers rated for full three-phase duty with a [2] [4]-hole spade or an eyebolt connector. The high voltage bushings shall be mounted in segment [1] [2] [3] [4] of the transformer.

2. [] The transformer shall be provided with [three (3)] [six (6)] sidewall mounted high voltage bushings, [200 amp wells with inserts] [600 amp dead-break] for deadfront application and arranged for [radial] [loop] feed configuration. The high voltage bushings shall be mounted in segment [2] [4] of the transformer.

3. [] The applicable bushing configuration shall be specified on the inquiry.

K. Low voltage bushings and terminals

1. [] The low voltage bushings shall be [sidewall] [cover]-mounted. For voltages less than 1000V bushings shall be molded epoxy with a [4][6][8][12][16]-Hole NEMA® spade. Low voltage bushings above 1000 V and all cover-mounted bushings shall be electrical grade wet

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process porcelain. The low voltage bushings shall be located in the segment opposite of the specified high-voltage configuration.

2. [] The applicable bushing configuration (phasing) shall be specified on the inquiry.

L. Overvoltage Protection

1. The overvoltage protection scheme provided with the transformer shall consist of one of the following attributes. If for any reason a special protection scheme is required it shall be clearly stated on the inquiry. Note: External arresters will not be provided in throats or flanges.

a. [] Primary overvoltage protection shall be provided by externally mounted, UltraSIL polymer-housed Evolution Distribution Class MOV arresters.

b. [] Primary overvoltage protection shall be provided by externally mounted, UltraSIL polymer-housed VariSTAR Intermediate Class MOV arresters.

c. [] Primary overvoltage protection shall be provided by externally mounted, UltraSIL Polymer-Housed VariSTAR Station Class MOV surge arresters.

d. [] Primary overvoltage protection shall be provided by VariSTAR [light-duty] [heavy-duty] under-oil MOV Distribution Class arresters.

e. [] Provisions for arresters

f. [] Primary overvoltage protection shall consist of elbow type MOVE arresters in conjunction with deadfront bushing wells and inserts.

2. To demonstrate the increased power reliability requirement to the mission critical load by reducing the possibility of transformer failure, the manufacturer shall provide the following with the proposal; test documentation to demonstrate the transformer design proposed is able to withstand switching transient voltages and avoid harmful resonant frequencies without the use of a snubber circuit or a system study. (note: CLT/HDC designs require FR3 high fire point fluid)

3.

2.04 INTEGRAL VACUUM FAULT INTERRUPTER

A. Ratings

1. The switchgear shall be rated* [15 kV, 12.5 kA] [15 kV, 16 kA] [25 kV] [35 kV] as follows:Nominal Voltage 15 kV 15 kV 25 kV 35 kVMaximum Design Voltage, kV 15.5 15.5 27.0 38.0BIL, kV 95 95 125 1501-Minute Withstand Voltage (60 Hz), kV   35 35 60 70Momentary Current, 10 Cycles (sym.), kA   12.5 16.0 12.5 12.53-second Withstand Current (sym.), kA   12.5 16.0 12.5 12.5

Fault Interrupter

Continuous Current, (max), A 900 900 900 900Interrupting Current (sym./asym.) 12.5/20.0 16/25.8 12.5/20.0 12.5/20.0Making Current (sym.), kA 12.5 16.0 12.5 12.5Cable Charging Interrupting Current, A 10.0 10.0 25.0 40.0

Load-Break SwitchContinuous Current, (max), A 600 600 600 600Load Switching, A 600 600 600 600Fault Making, kA 12.5/20.0 16/25.8 12.5/20.0 12.5/20.0

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(sym./asym.)Minimum Full Life Fault Interrupting Duty Cycleper IEEE Std C37.60™-2003 standard (2 duty cycles)

Number of Operations

Percent of Interrupting Current Rating: 15-20% 88 88 88 88

45-55% 112 112 112 112

90-100% 32 32 32 32

Total 232 232 232 232

* Continuous and short-circuit currents may be limited by ratings of selected bushings.

B. Vacuum Fault Interrupters

1. The transformer shall incorporate a vacuum fault interrupter for overcurrent protection, such that the major dielectric media is never contaminated by circuit interruption arc products. The interrupter shall be manually resettable, with no consumable parts (i.e. fuses). The maximum interrupting time from issuance of a trip signal from the electronic control shall be 2 cycles.

2. The vacuum fault interrupter may be tripped via the incorporated relay control by sensing anomalies in the system provided there is adequate sensing equipment also incorporated into the transformer. That is, the VFI may be tripped (opened) in the event of anomalies such as, but not limited to, overcurrent, over/undervoltage, over temperature, over pressure, under frequency, etc. provided the appropriate associated devices are also incorporated into the transformer (i.e. potential transformers, thermometers, pressure relief devices, transducers, etc.) and the appropriate relay control is selected.

3. To maximize safety to the operator, the interrupter shall incorporate a trip-free mechanism to prevent the possibility of holding the interrupter mechanism closed under a faulted circuit condition.

4. The vacuum fault interrupter shall act as a three-phase group operated circuit breaker. The trip mechanisms for each phase shall be mechanically linked and the electronic control shall be set so that an overcurrent condition on any one phase shall simultaneously trip all three phases. A single operating handle shall be provided for manual opening, reset and closing. The operating handle(s) shall be mounted on the front plate of the tank in close relation to the VFI being controlled and shall have three distinct operating positions corresponding to the vacuum fault interrupter positions of closed, open, or tripped. A pointer attached to the handle shall be provided for ready identification of the handle’s position. The handle shall be designed for operation with a lineman’s hot stick and have a push to close / pull to open / pull to reset operation requiring no more than 75 lbs. of force and 60 degrees of movement for complete operation. Except when equipped with the optional motor operator, when the vacuum fault interrupter is tripped by automatic action of the VFI control, the operating handle shall drop to an intermediate position between its closed and open positions, to provide indication that it is tripped. The operating handle assembly shall include provisions to padlock the handle in the open position.

C. Electronic Trip Control

1. The protective relays for the transformer protection shall be a single multifunction, microprocessor-based relay that incorporates restrained differential protection for two windings with fixed or variable percentage, using one or two settable slopes with adjustable intersection points and minimum pickup.

2. The relay shall be Eaton device type ETR-4000, ETR-5000, or approved equal differential relay having all, but not limited to, the features and functions herein specified.

3. Relay shall be wired to directly trip the VFI mechanism.

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4. The relay shall be a solid-state microprocessor-based multifunctional type that operates from a 5 ampere or 1 ampere secondary output of current transformers. The relay shall provide ANSI 50/51 protective functions, and ANSI 50/51N or 50/51G ground fault protection functions for each winding as shown on the plans or as determined by the coordination study. The relay shall be configurable between true rms or fundamental sensing for each phase and ground. Ground element shall be capable of being utilized in residual, zero sequence, ground source connection schemes, or deactivated.

5. The current transformer ratings being used for percentage restraint differential protection, phase, negative sequence, and ground protection feeding the device shall be programmable for current transformers with primary current ratings from 1 through 10,000 amperes

6. Provide phase and ground (as applicable) CT’s on transformer secondary. CTs will be connected to transformer relay via test switches within control cabinet. CT ratio shall be as appropriate for the full amp output of the given transformer kVA rating.

7. Provide phase and ground (as applicable) CT’s on transformer primary. CTs will be connected to transformer relay via test switches within cabinet. CT ratio shall be as appropriate for the full amp output of the given transformer kVA rating.

8. Control cabinet will be equipped with ABB FT-1 type test switches as needed for application or approved equal

9. Control cabinet will be supplied with terminal block for customer connections

10. Control cabinet will be supplied with 24V UPS system supplied by 120VAC from internal CPT and 12VDC from cabinet mounted 12V battery capable of 24hour back up (optional: customer supplied power)

11. Control cabinet to include heater

12. Control cabinet will be NEMA 4X, UL listed, 100% stainless steel box

13. The relay shall provide, but is not limited to, the following protection devices:

a. Percentage Restrained Differential Protection (87). The relay shall incorporate restrained differential protection for two windings with fixed or variable percentage, using one or two settable slopes with adjustable intersection point and minimum pickup values.

b. Harmonic Elements. The relay shall incorporate second-, fourth-, and fifth-harmonic elements, with the choice of temporarily or permanently desensitizing the differential protection to prevent restrained differential element operation during inrush or overexcitation conditions; it shall be possible to set the fifth-harmonic element to warn user of overexcitation condition.

c. Unrestrained Differential Protection (87H). The relay shall include unrestrained differential protection to produce rapid tripping for severe internal faults.

d. Ground Differential Protection (87GD) or Restricted Earth Fault Protection (REF). The relay shall incorporate restricted earth fault protection for the detection of ground faults in wye-connected windings.

e. Phase overcurrent (50/51): Four inverse time overcurrent (51-1, 51-2, 51-3, 51-4) functions and four instantaneous overcurrent (50-1, 50-2, 50-3,50-4) functions with adjustable time delay. Each element can be assigned to either side of the transformer.

f. Ground overcurrent (50R/51R): Two inverse time overcurrent (51R-1, 51R-2) functions and two instantaneous overcurrent (50R-1, 50R-2) functions from calculated values with adjustable time delay. Each element can be assigned to either side of the transformer.

g. Ground overcurrent (50X/51X): Two inverse time overcurrent (51X-1, 51X-2) functions and two instantaneous overcurrent (50X-1, 50X-2) functions from measured values with adjustable time delay. Each element can be assigned to either side of the transformer.

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SECTION 26 12 13.03

h. The phase, negative sequence, and ground protection curves shall be independently field-selectable. Curves shall be selectable from the following:

i. IEEE: Moderately inverse, very inverse, extremely inverse

j. IEC: A, B, C or D

k. Thermal: Flat, lt, I2t, I4t

14. The relay shall have 8 contact outputs that may be programmed for any protection function operation output

15. The relay shall have a front panel display of relay condition, and 14 programmable LEDs that can be used for trip condition or breaker status

16. The relay shall have a LCD display with LED background illumination capable of displaying the following information with metering accuracy of +/- half (0.5) percent of measured value (ln) for ln < 2 ln and +/- one (1) percent of measured value (ln) for ln > 2:

17. Relay will be able to measure the following values from the transformer (*voltage and power measurements require inclusion of PTs and PT inputs):

a. Individual RMS and fundamental phase currents

b. Ground RMS and fundamental current

c. Phase-to-ground and phase-to-phase voltages with phase angles

d. Watts

e. Vars

f. VA

g. Frequency

h. Power factor – apparent and displacement

i. Minimum/maximum values of current, voltage, watts, vars, VA, frequency, apparent pf and displacement pf

j. phase angles

18. Relay shall have the following features:

a. Trip coil-monitoring and IRIG-B

b. Zone selective interlocking capability

c. Real-time clock for stamping of events, trips and minimum/maximum values with

d. 1ms time resolution or better

e. User interface for programming and retrieving data from the front of the unit without additional equipment

f. Eight (8) contact inputs that are user programmable

g. Continuous self-testing of internal circuitry, self-diagnostic capability.

h. Programmable lockout/self-reset after trip function (86 lockout)

i. Programmable set points for device curve selection

j. Programmable inputs, such as current transformer ratios

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SECTION 26 12 13.03

k. Relay shall be suitable for operating temperatures from -20 degrees to 60 degrees C. Relay shall be suitable for operating with humidity from 0 to 95% relative humidity

19. Relay shall record information on the last 20 faults including:

a. Date, time, and currents at the time of fault

b. Relay shall record 3600 cycles of waveform data for the current

c. Relay shall record the last 300 events into an event log with date and time stamping

20. Relay shall have the following communications ports available if specified:

a. Rear communications port(s) that support: IEC61850, Modbus TCP, and DNP3.0 TCP via RJ-45 connector

b. A USB front communication port for programing and interrogation of the relay via personal or laptop computer

c. Communication ports shall have the ability to transmit all information contained in the relay such as currents, set points, cause of trip, magnitude of trip current, and open-close trip status over the connected network.

21. Relay trip contacts shall not change state if power is lost or an undervoltage occurs. These contacts shall only cause a trip upon detection of an overcurrent or fault condition based upon programmed settings

22. The relay shall be suitable for operating on control power with a nominal input voltage of 24Vdc

23. The Relay shall be fully programmable through the face of the relay. In addition, a means to be able to program the relay through a communication port needs to be provided.

24. Meet the specified time-current curve immediately upon energization.

25. No “warm-up”, initialization, or arming time delays adjustments shall be necessary.

26. No minimum load requirement or battery back-up device shall be necessary to meet the specified time-current characteristics.

D. VFI Optional Features

1. [] Motor Operators

a. When specified, a DC motor operator, with integral control shall be supplied for the S-VFI transformer. The unit shall include the appropriate VFI mechanism for use with motor operation and all standard motor operator mounting hardware. The motor operator shall utilize 24-Vdc motor actuators to open and close the respective VFI. The time required to open or close the VFI shall be approximately 2.5 seconds. The motor control shall be equipped with a 50 amp-hour sealed lead acid gel-cell battery to supply energy to activate the motor operator and control functions. Battery charge shall be maintained by a temperature/voltage regulated charger within the motor control that shall be capable of fully re-charging a low battery within 24 hours.

b. The motor control shall utilize an integral 120-Vac potential transformer for control power supply. (If a user supplied power supply to the motor control has been specified, the unit shall be provided with all necessary wiring connections.)

c. The motor control shall include the following features:

1) Open, Close, and Stop pushbuttons shall be provided for operation of the motor actuator.

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SECTION 26 12 13.03

2) Open and Closed indicating lights shall be provided to indicate status of the VFI. These status lights shall use auxiliary switch inputs from the source VFI to determine open or closed status.

3) Opening and closing indicating lights shall be provided to verify that the motor actuator is in process of opening or closing a switch. A lamp test pushbutton shall be provided to confirm that indicating lights are functional.

4) A Power On/Off toggle switch shall be provided that shall disconnect the dc voltage supply from the control and the motor actuator and shall function as a dc circuit breaker to interrupt the dc supply in the event of a short circuit or overload.

5) An indicator light shall be provided to verify that 12Vdc battery is healthy and voltage is present and that the battery charging circuit is providing a charging voltage to the battery.

6) A Local/Remote toggle switch shall be provided. In the Local position, the switch shall allow operation of the motor actuator by the pushbuttons on the control panel only and shall not allow remote or SCADA operation. In the Remote position, the switch shall only respond to the remote or SCADA operation of the motor actuator.

2. [] RVAC switch on Loop

1) Added to the transformer design (when configured with loop feed primary connections) will be an RVAC switch on the outgoing leg of the loop. The RVAC is a 2-position, under-oil vacuum loadbreak switch rated for 600amp continuous at 35kV. The RVAC switch will feature an operating handle that can be manually operated to open/close the transformer loop or be paired with the above ‘motor operator’ and controlled externally through a control on the control box swing panel or remotely through the feeder relay. The addition of the RVAC switch and motor operator will allow for remote sectionalizing of the transformer loop. When specified the RVAC may be paired with a Kirk Key interlock to another under-oil loadbreak switch on the opposite leg of the loop for full isolation of the transformer from the line.

3. [] Visible Disconnect Window

a. The VFI mechanism will be mechanically interlocked with a 3ph ganged disconnect switch such that the VFI must be in the ‘open’ position to operate the disconnect. The contacts of the visible disconnect switch will be clearly visible through a 4” x 11” view window. When specified with motor operator: Visible disconnect switch must be interlocked with auxiliary contacts such that the motor cannot close the VFI mechanism when the visible disconnect is in the ‘open’ position.

4. [] Open/Closed Semaphores

a. When specified, an Open (green) /Closed (red) mechanical semaphore shall be provided and shall indicate the open or closed status of the vacuum fault interrupter. The semaphore shall be visible through a window on the tank in direct logical proximity to the operating handle of its fault interrupter. Semaphore is provided as standard with motor operator kit.

5. [] Kirk-Key Interlock Provisions

a. When specified, mounting provisions for Kirk key interlocks shall be provided on each switched and VFI protected way.

6. [] Auxiliary Switches

a. When specified, the VFI shall be provided with [one extra set] [two extra sets (non-motor op only)] of stage “a” and “b” auxiliary switches for the purpose of remote indication of status. These auxiliary switches shall be rated for 15-amps @ 120-Vac / 1-amp @ 125-Vdc and wired to an external terminal strip.

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SECTION 26 12 13.03

7. [] Partial Range Current Limiting Fuses in series with VFI

a. When specified, the VFI shall be provided with separate partial range current limiting fuse. The VFI will be connected in series with the partial range current limiting fuse. The partial range current limiting fuse will provide protection up to 50 kA.

8. [] Arc-flash relay (w/ light sensing)

a. When specified transformer LV compartment of LV throat connection will be outfitted with arc-light sensors that are wired to an arc-flash relay. The arc-flash relay will work in conjunction with the over current protection system, simultaneous detection of arc-light and overcurrent events will send a trip signal to the integral VFI and open the transformer primary circuit.

9. [] Close-coupled to Eaton Arc-Quenching Switchgear

a. When specified transformer will be specifically designed to be close-coupled to the Eaton LVA “Arc-Quenching Switchgear” or “AQS” lineup. This design will utilize the Eaton arc-flash relay within the AQS and light sensors within the AQS and transformer throat to initiate the tripping of the VFI while simultaneously creating a low impedance fault within the Arc-Quenching Device (AQD) located in a Magnum DS breaker slot of the Eaton AQS. Primary and secondary current transformers and microprocessor-based relay for overcurrent sensing/protection shall be included in the main transformer structure/control cabinet. Eaton arc-flash relay within AQS shall communicate with relay within AR-VFI transformer to initiate VFI trip. (more information see: Eaton Arc-Quenching Switchgear).

2.05 ACCESSORIES

A. The following standard accessories shall be provided:

1. De-energized tap-changer

2. 1.0” upper fill plug with filter press connection

3. 1.0” drain valve with sampling device

4. Cover-mounted automatic pressure relief device

5. Welded cover with bolted manhole

6. Lifting lugs (4)

7. Liquid level gauge

8. Dial type thermometer

9. Pressure/vacuum gauge

10. SS ground pads (4)

11. Nitrogen blanket with purge valve

12. Touch-up paint (2 aerosol cans)

B. The following optional accessories shall be provided if specified:

1. [] Copper low voltage bushings (standard with all-copper windings)

2. [] Bleeder valve

3. [] NEMA® 4 control box (standard with fan package)

4. [] NEMA® 4X control box (stainless steel)

5. [] NEMA® 7 control box (explosion proof)

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SECTION 26 12 13.03

6. [] Rapid pressure rise relay

7. [] Seal-in panel for rapid pressure rise relay

8. [] Forced air fan control package

9. [] Winding temperature indicator

10. [] Auxiliary contacts for liquid level gauge

11. [] Auxiliary contacts for dial type thermometer (standard with fan package)

12. [] Auxiliary contacts for pressure/vacuum gauge

13. [] Auxiliary contacts for pressure relief device

14. [] 1.0” globe-type upper fill valve

C. Special Features

1. The following special features may be provided if specified:

2. [] All copper windings

3. [] Dead front HV termination

a. [] Loop feed

b. [] Radial feed

4. [] Sectionalizing switch, 4-position T-blade, 600 A, make-before-break option

5. [] 304L stainless steel construction

a. [] Tank base

b. [] Primary enclosure

c. [] Secondary enclosure

d. [] 100% 304L stainless steel construction

6. [] Cooling

a. [] Mild steel radiators

1) [] Welded

2) [] Removable

b. [] Stainless steel radiators

1) [] Welded

2) [] Removable

c. [] Galvanized steel radiators (removable and unpainted)

7. [] K-factor transformer

8. [] Positive nitrogen pressure oil preservation system

9. [] Current transformers for relaying/metering

10. [] Containment pan for indoor use for 100% fluid containment

11. [] Factory Mutual® (FM) approved transformer (for NEC® Code-listed installations on, near, or inside of buildings)

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SECTION 26 12 13.03

12. [] UL® Listed and Classified transformer (for NEC® Code-listed installations on, near, or inside of buildings) per UL® XPLH

13. [] UL® Listed transformer (certifying compliance with IEEE® standards only) per UL® XPLH

D. Optional transformer evaluation

1. [] No unit evaluation but include quote losses as reference only on bid.

2. [] Unit loss evaluation guaranteed average losses. Criteria to properly evaluate quoted losses:

a. Core loss evaluation (A-factor) ____ $/watt

b. Winding loss evaluation (B-factor) ____ $/watt

2.06 FINISH PERFORMANCE REQUIREMENTS

A. The tank coating shall meet all requirements in IEEE Std C57.12.28™-2014 standard including:

1. Salt Spray

2. Crosshatch adhesion

3. Humidity

4. Impact

5. Oil resistance

6. Ultraviolet accelerated weathering

7. Abrasion resistance–taber abraser

PART 3 EXECUTION

3.01 PRODUCTION TESTING

A. All units shall be tested for the following:

1. Ratio, polarity and phase relation tests using all tap settings

2. Winding resistance measurement tests

3. Insulation power factor

4. Full wave and reduced wave impulse test

5. Applied and Induced potential tests

6. No-Load losses at rated current

7. Total losses at rated current

8. Percent impedance at rated current

9. Excitation current (100% voltage) test

10. Leak test

B. Transformers shall conform to efficiency levels for liquid immersed distribution transformers, as specified in the Department of Energy ruling “10 CFR Part 431 Energy Conservation Program: Energy Conservation Standards for Distribution Transformers; Final Rule; April 18, 2013.”

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SECTION 26 12 13.03

Manufacturer shall comply with the intent of all regulations set forth in noted ruling (commonly referred to as DOE 2016).

C. The manufacturer shall provide certification upon request for all design and other tests listed in IEEE Std C57.12.00™-2010 standard, including verification that the design has passed short circuit criteria per IEEE Std C57.12.00™-2010 and IEEE Std C57.12.90™-2010 standards.

D. In the event of proposal bid evaluated with guaranteed losses due to a loss evaluation (see section 11.0), manufacturer shall conform to guaranteed average losses as specified in IEEE Std C57.12.00™-2010 standard. The no-load losses of a transformer shall not exceed the specified no-load losses by more than 10%, and the total losses of a transformer shall not exceed the specified total losses by more than 6%.

3.02 SHIPPING

A. Transformers shall be loaded and unloaded with overhead cranes. No pallet shall be provided.

3.03 DATA WITH PROPOSAL

A. The following data shall be submitted with the proposal:

1. Core losses (when requested per Sections 3.01 D and 2.04 D).

2. Winding losses (when requested per Sections 3.01 D and 2.04 D).

3. Percent impedance

4. Typical bid drawing

B. The following checked data shall be submitted with the proposal:

1. [] Exciting Current @ 100% and 110% rated Voltage.

2. [] Efficiencies must be provided at loading levels of 100%, 75%, 50%, and 25%.

3. [] Percent regulation must be provided at 0.8 PF and 1.0 PF.

4.

3.04 DRAWINGS

A. The following will be provided by request after receipt of order:

1. [] Construction drawings

2. [] Record drawings

3. [] Approval drawings

4. [] CAD drawings

3.05 SERVICE

A. The manufacturer of the transformer shall have regional service centers located within 2 hours flight time of all contiguous 48 states. Service personnel shall be factory trained in commissioning and routine service of quoted transformers.

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