Contractor_Questions_and_Answers.pdf

Contractor’s Questions & Answers

1. Will any of these buildings require a TVSS and if so, is there a specific manufacturer the government wants to use?

Answer: See Attachment.

2. Is there a specific manufacturer the government wants to use on all the gear? (i.e. panels, disconnects, dry type transformers)

Answer‐ The government would like ALL contractors to bid Square D gear.

3. Will rigid conduit be required where above ground?

Answer: Yes, all 90’s and exposed pipe coming from underground service or if services are overhead all service drops will be rigid. Sized per NEC for 600 amp service.

4. Does the service entry wire used need to be XHHW or can it be THHN?

Answer: if services are overhead THHN is good. If service is underground USE‐2 will be required.

5. Is the service entry wire required to be copper?

Answer: Yes, service wire will be copper.

6. Are there any specific size breakers needed in the 277/480v and 120/208v panels?

Answer: The only breakers the contractor will supply is what is needed for dry cell transformer in 480V panel and in 208V panel. Government will supply ALL branch circuits in 480V and 208V panel.

7. Are we to fill the remaining spaces in the panels with single pole 20‐amp breakers?

Answer: No.

8. What size dry type transformers are required to feed the 120/208v panels?

Answer: Per NEC to get a 200 amp 120/208V panel a 75KVA will required.

9. What size and class of poles are required?

Answer: Poles for transformers will be class I 50 foot, all the remaining poles can be class II 50 foot.

10. What size new aerial pole mounted transformers will be required?

Answer: 167 KVA 7620132Y 277/480V. With taps 2.5% above and below.

11. Will the overhead service be ACSR or copper and what size will it need to be?

Answer: 1.0 ACSR.

12. Will the poles require pole roofs?

Answer: Yes.

13. What ratio of Current Transformers for each building will be required?

Answer: 600 to 5. 3ea per building.

14. What size ground rod will be required?

Answer: 5/8 copper clad.

15. Is exothermic welding required on ground rods?

Answer: Compression lug will work.

16. What voltage will be required on the primary?

Answer: Current voltage on main road 7620.

17. What is the location, in relation to building main disconnect, for the 277/480 V 600 amp panel inside or outside of each building?

Answer – The panel will be placed behind the main disconnect on inside of building. Pipe will be sized per NEC on 600 amp rated wire.

18. What is location of 208/120 V 200 Amp panel in each building?

Answer – The 208/120v panel will be to the left of the 600 amp 480v panel with the pad mount transformer between the 2 panels on housekeeping pad.

19. Who provides CT'S for the Schneider Electric Metering Panel on each building?

Answer‐ The contractor that wins bid will be required to set meter and install CT’s per spec of smart meter.

20. Is there a need for any other breakers, other than main and breaker for transformer feed, for the 277/480V 600 Amp panels in each building?

Answer‐ Pine Bluff Arsenal will install any extra branch circuit breakers inside all panels inside the 81 buildings.

21. Is there a need for any other breakers, other than main, for the 208/120 200 Amp panel in each building?

Answer‐ Pine Bluff Arsenal will install any extra branch circuit breakers inside all panels inside the 81 buildings.

22. On detailed scope of work #3A. What is meant by 3 point grounding?

Answer‐ Grounding of pad transformer will be grounded Per NEC. 1‐ case ground 2‐ building ground 3‐ if availably allows building steel. Note‐ 2 and 3 may already be connected so only 2 points of grounding will be needed. COR will make that determination on site.

23. Could you please send information on the smart metering system that is in use on base?

Answer: See Attachment.

24. Could you please send information on the tracer summit power monitoring program?

Answer: The Smart Meter we have specified is compatible with the tracer system we have on PBA.