Att_5_Revised_VAFB_Standard_Requirements_for_Substation_Power_Transformers.pdf

Attachment 5 FA4610-15-R-0010

VAFB Standard Requirements for Substation Power Transformers

REVISED 12 MAY 2015

The contractor shall provide a stainless steel transformer with the following requirements:

1) The transformer shall have a base that is capable of being slid into position using jacks and roll bars.

2) The contractor shall provide the Transformer with standard Lifting Lugs capable of supporting the transformers weight during installation.

3) The transformer’s Ground Pads shall be stainless steel.

4) The contractor shall provide a Stainless Steel Diagrammatic Nameplate with the standard transformer information in accordance with industry standards.

5) The transformer shall have all industry standard Access Holes with Covers and Gasket Grooves.

6) The transformers top cover shall be Welded rather than bolted.

7) The transformer shall have Cooling Radiators that are stainless steel. The radiators shall have an isolation valve and shall be removable from the transformer for maintenance or replacement. The transformer shall be painted with a standard coating in order to prevent corrosion.

8) The internal winding shall be Copper.

9) The transformer shall have the industry standard Nitrogen Blanket.

10) The transformer shall have High Voltage Drawlead Bushings, 70 kV, 550 kV BIL, Extended creep (for high pollution environments), CORIP, with 4-Hole stainless steel NEMA Pad. Please note that this is a non-industry-standard bushing.

11) The transformer shall have Low Voltage Bottom Connected Bushings, with ratings of 15 kV, 110 kV BIL and shall be mountedwith a 4 Hole NEMA stainless steel Pad.

12) The transformer’s oil system shall have a 2” Combination Lower Drain and Filter Valve with the ability for the user to take oil Samples.

13) The transformer shall have a 1” Upper Filter Valve.

14) The transformer shall have an industry standard Pressurization Test Point with ½” Ball Valve.

17) The transformer shall have a Pressure Vacuum Gauge with 2 Sets of Contacts and Bleeder.

18) The transformer shall have a Pressure Relief Device with 2 Sets of Contacts.

20) The transformer shall have Jack Pads with Pulling Eyes that can support the transformer’s weight during its installation.

21) The transformer shall have a Stainless Steel Junction Box with that is rated for NEMA 4Xwith Bolted Bottom Plate.

22) The transformer shall have a Sudden Pressure Relay (SDP Relay). The contractor shall disconnect the wiring from the existing transformer’s SDP Relay, and reconnect the wiring to the new transformer’s SDP relay.

23) The transformer shall have High Voltage Arresters, Station Class, Polymer Housed, 72 kV, 57 kV

MCOV.

24) The transformer shall have a Standard-Size Junction Box (stainless steel) to allow feed-thru connection points for High Voltage and X0 Current Transformers and Core Ground Bushing located in blockhouse

25) The transformer shall have Interconnecting Piping with Valve between LTC and Main Tank.

26) The transformer shall have a Load Tap Changer Switch, Reinhaunsen Type RMV-II (or equivalent).

29) The Load Tap Changer (LTC) shall have a Drain Valve where the user can take oil samples.

30) The Load Tap Changer (LTC) shall have a Hand Crank Operating Location.

34) The transformer shall have Low Voltage Arresters, Station Class, Polymer Housed, 9 kV, 7.65 kV

MCOV.

36) The transformer shall have industry standard Bolt on Fall Protection Tower Mounting Plate, WINSAFE GM 135CP (or equivalent).

39) The contractor shall provide a Standard-Size Junction Box (stainless steel) to allow feed-thru connection points for Low Voltage Current Transformers located in the substation D blockhouse.

42) 4/0 copper Ground Cable shall be used to connect the Arresters Ground Pads to the Base Ground Pad.

43) The transformer’s Low Voltage Air Terminal Chamber shall include a Strip Heater and thermostat to control moisture.

45) The transformer shall not include an external radiator cooling fan.

Additional Requirements:

1) The Transformer shall be designed for Full Vacuum Filling.

2) The transformer shall be designed for Seismic Zone 4 Stresses.

3) The Transformer shall be designed for Sealed Tank Oil Preservation.

4) The transformer shall be filled with Type II Mineral Oil.

5) The transformer shall be rated for Outdoor Service.

6) Both the Main tank and LTC Tank shall be Stainless Steel and Painted in accordance with ANSI-70 (Enamel over Epoxy).

7) The Fill, Drain, and Utility Valves shall be Bronze.

8) The Radiator Valves shall be Carbon Steel.

9) There is an existing Load tap changer oil filtration unit attached to the existing transformer. The contractor shall disconnect the oil filtration unit from the existing transformer and reconnect it to the new transformer that the contractor is installing.

10) All External Hardware shall be Stainless Steel including Bolts and Washers. The Nut however shall be made of Silicon Bronze.

11) The Accessory Wiring that is being installed shall be in Rigid Galvanized Steel Conduit that is painted with industry standard paint.

12)

13) The Transformer shall be shipped with an Impact Recorder.