QandA_23APR2019.pdf

Question & Answer for Rectifier and Battery Equipment Replacement and Testing for BLDG P2441 at Fort Bragg, NC

1. Do you have a floor plan for this office?

2.

3. Location of the COGB for the new DC Plant Reference Ground and Chassis Ground?

Estimated cable footage? Directly behind existing power board. ~10 ft.

4. How many rectifiers are being installed? Number of rectifiers depends on system being installed. Must provide and/or exceed at least 95 amps and be N+2 redundant

5. Who is doing the AC? (If we are covering the AC see questions below.) Contractor is doing the AC work.

a. How far is the AC Panel from the location of the DC Plant? Estimated distance from Plant to PDSC? AC panel is a 30 foot run to the power board.

b. What Brand/Model# is the AC Panel? Square D NQOD44SL225CU Series E2

c. What is the existing AC Breakers size that feed the rectifiers? 25 amp breakers (double-pole)

6. How many Secondary DC Circuits? 18 secondary loads

a. What size are the secondary Circuits. Breaker sizes:

3A - 1 EA

20A - 1 EA

30A - 8 EA

45A - 2 EA

50A - 4 EA

175A - 2 EA

b. Can we h-tap above the new DC Plant or will the cables be long enough to re-terminate inside the DC Plant? H-Tapping is permitted

c. Who is supplying the DC Breakers or Fuses for the secondary circuits? Contractor is to provide DC breakers.

7. Is the existing ironwork being supported off the top of the bays or is it supported from overhead? Iron work secured on brackets mounted to cinder block wall.

8. What are we supposed to do with the old DC Plant once it has been removed? Contractor shall dispose of removed power plant.