Questions and Answers for Replace Building Transformers_responses 1.pdf

Questions and Answers for Replace Building Transformers

1. I was hoping there would be serial number plates or spec plates on the outside of the outdoor transformers, but there was not. I went to each one yesterday to verify. Our Vendors are requesting this information to help them get new transformers that have the same dimensions to be installed on the existing pads and existing terminations.

They are having trouble doing this with the information provided so far. Can you provide photos of the Spec Plate for each outdoor transformer to be replaced? If not photos can you provide the drawings/specs for each of them?

Response: Should this information be required the contractor shall coordinate with the COR a preliminary outage to obtain pictures of the interior of the transformer.

2. Is there any onsite acceptance testing required for the oil filled transformers? If so, would this testing follow NETA requirements?

Response: Refer to Specification 26 12 19 3.2 and 3.3 for testing.

3. Is there any onsite acceptance testing required for the LV switchgear assemblies and/or circuit breakers? If so, would this testing follow NETA requirements?

Response: Refer to Specification 26 24 13 3.2 for testing.

4. Is there any onsite acceptance testing required for the MV disconnect switches? If so, would this testing follow NETA requirements?

Response: Refer to Specification 261313 Med Voltage Circuit Breaker Switchgear specification included with this response.

5. For the MV cable testing, what duration of time should the VLF cable tests be held (i.e.

30 minutes, 1 hour, etc.)?

Response: The cables shall be tested for 1 hour.

6. Are the following pad mount style or unit substation style transformers? TESS1, TESS2, TESS3, TSS1, TSS2, TSS3

Response: TESS1, TESS2, TESS3, TSS1, TSS2, TSS3 are all substation style.

7. Are the following items to be replaced with the equipment the same footprint? Also, are they to be UL891 or UL1558? BUILDING 2A ROOM G066 - SQUARE D

SWITCHBOARD, SWITCHGEAR ESS3 BUILDING 143, SWITCHGEAR SS3 BUILDING

143, SWITCHGEAR ESS1 BUILDING 143, SWITCHGEAR SS1 BUILDING

143, SWITCHGEAR ESS2 BUILDING 143, SWITCHGEAR SS2 BUILDING 143

Response: The equipment is to be replaced with equipment of the same or smaller footprint so that NEC clearances are maintained. Refer to Specification 261313 Med Voltage Circuit Breaker Switchgear specification included with this response for UL information.

8. Please provide a floor plan drawing for Bldg. 2A Mechanical Rooms? This room is changing as we speak. So, This will fall under Site investigation to the winning Contractor.

9. Are the existing transformers Live front, 200 or 600 amp terminations for the primary side?

Response: It is our belief that the transformers are dead front 200A. Contractor to coordinate preliminary outage to verify and notify COR of any discrepancies.

10. Note 3, Sheet E-102 states to replace the 500mcm cable approx.. 70 feet. Is this 600 volt cable or 15kv Cable?

Response: This is the secondary cable, on the secondary side of the transformer.

11. Are the two 1600 amp 3P NEMA 3R fusible disconnects switches on sheet E-103 Detail

#4 to be deleted with Alternate #1 bid item, (Square D gear)?

Response: Deducts will not be exercised as part of this project. All work listed as deducts shall be included in the base bid.

12. Alternate #2 States to Correct Code Violations in Bldg. #2a. I cannot find anywhere on the prints indicating what violations. Please clarify and give quantities of violations.

Response: The code violation to be corrected is the unfused service entrance conductors routed through the building. The addition of the two service entrance rated fused disconnects noted on Keynotes 12 and 13, E-103 corrects these violations.

13. Alternate #3 states to delete Transformer TR13-2 in Bldg. 13-2. I cannot find a

Transformer labeled that. Should this read Transformer 13-3? Please Clarify.

Response: The transformer being replaced is Transformer 13-3.

14. The drawings state some of the transformers feed other transformers. The Specs do not call for transformers to have feed through capability (A and B side bushings), or switches in the Primary compartment. Please confirm.

Response: The indication of one transformer feeding another refers to the status of the taps, in that if one transformer goes offline the other transformer does as well, it is not intended to indicate that one transformer feeds through to another. This should be field verified before the approval is given to order transformers.

15. There is not a Spec. for the six Unit Style Transformers. Please provide.

Response: Refer to Specification 261313 Med Voltage Circuit Breaker Switchgear specification included with this response.

16. The Price/Cost Schedules on Pages 5 & 7 of 74 in the Solicitation only have a line to put the Base bid number. Nowhere for the three Alternates that are listed in Section 01 00 00 page 1 para.1.3 in the specs. Please clarify.

Response: Deducts will not be exercised as part of this project. All work listed as deducts shall be included in the base bid.

17. Does temporary power need to be provided by the contractor while the 13 Pad

Mounted transformers are being swapped out or can the Govt. Existing Generators be used? These outages will be during the weekend and last 4 to 6 hours each.

Response: Buildings 143, 2, 2A, 13, & 170 would require generators to be used for temporary power for any work which would interrupt any power to any portions of the building.

18. Detail #2 on page E-105, of the Square D panel board in Bldg 2A shows the 480 volt main breaker installed in what is labeled the 120/208 panel. Are the two panels mislabeled? Please Clarify.

Response: The main shown in the 208V/120V switchboard is mislabeled and is a 208V breaker.

19. Detail #1, on Sheet E-103, Notes #12 & 13, indicate to install two 1600a Disconnect

Switches. Is this correct? The transformers are inside the Building. What will the two disconnects feed? Please clarify.

Response: The disconnect switches are to be the service entrance disconnects for the two switchboards. The transformers serving these two disconnects are located outside.

20. Are we to match existing metering on the new switchboards and transformers? Please provide details for the metering requirements.

Response: Existing exterior pad mounted transformers are not and will not be metered. Interior Medium voltage single ended switchgear have meters and will have new metering installed in the low voltage lineup, See Specification 25 10 10 Section 2.1 for the meter characteristics. New low voltage switchboards which replace the existing switchboards will also have the same class of meter installed.

21. Will the six unit subs replacements be “switchboard” or “switchgear” construction?

Response: The six unit substation replacements will be switchgear construction.

22. Please provide details of where the SPD’s will be required. They are not shown on the drawings.

Response: SPDs are to be included integral to each low voltage switchboard being replaced.

23. Since no access was given to open the pad mounted transformers can the Contractor assume that the primary & secondary cables are long enough to make up on the new PMT or should there be contingencies included in the bid to provide additional cables.

Response: The secondary and primary connecting cables can be assumed to be of sufficient length to make up on the new pad mounted transformer.

24. Will a coordination study need to be provided with new switch boards?

Response: Refer to Specification 26 05 73 included with this response.

25. Are the transformers live or dead front on the primary side?

Response: It is our belief that the transformers are dead front 200A. Contractor to coordinate preliminary outage to verify and notify COR of any discrepancies.

26. Are there PCB'S in the existing transformers?

Response: VA test results do not indicate the presence of PCBs in the existing transformers.

27. What are the procedures for the primary and secondary wires if the new transformer pads and bushings do not match up?

Response: The secondary and primary connecting cables can be assumed to be of sufficient length to make up on the new pad mounted transformer. New transformer pads are to be installed. Coordination of pad and transformer shall be the responsibility of the contractor.

28. Will we have an onsite storage area for the transformers and our lift?

Response: Yes, Contractor area beside parking lot T

29. Can we use refurbished transformers that have longer warranty and are made of all

American made parts?

Response: NO

30. Can the superintendent also be the QC and SSHO for this project?

Response: Superintendent may be SSHO. QC Manager shall be a separate individual and shall maintain a presence on site at all times while work is being performed.

31. How much time will be required for notification of building shutdowns?

Response: Contractor shall submit outage request 3 weeks in advance.

32. Is it the government’s expectation that all transformers will be replaced during normal business time with the exception of those listed as not on the loop?

Response: No. Outages will be after hours and on weekends

33. Please provide a one-line diagram for the campus MV electrical system.

Response: This will be provided following contract award.

34. Will all circuits in each switchgear require temporary power, including “spare” and/or “unlabeled” breakers? For example, ESS1 has two “unlabeled” 400A and one 600A breakers. Will these require temporary power during the switchgear upgrade?

Response: Any switchgear in Building 143 will require temporary power whenever one of the switchgear is replaced.

35. What are the manufacturer warranty requirements for the new transformers and switchgear?

Response: See Specification 26 05 11. All work performed and all equipment and material furnished under this Division shall be free from defects and shall remain so for a period of one year from the date of acceptance of the entire installation by the COR for the Government.

36. Please provide photos of the interiors of the existing transformers. Specifically, it would be helpful to see the terminations inside each transformer and the approximate length of conductors (or height of terminations) inside each cabinet.

37. Please provide photos of the nameplates of the existing transformers (the ones without visible nameplates; assuming that they are inside the transformer door).

Response: Should this information be required the contractor shall coordinate with the COR a preliminary outage to obtain pictures of the interior of the transformer.

38. Electrical single line diagram for the complete compound to determine loads and outages

Response: Information that is available will be provided to the successful Contractor following contract award.

39. Pictures of the existing medium & low voltage terminations at the transformers and switches inside if possible. If not possible, please confirm if all MV terminations are load break elbows and type of connection for LV secondary side (mechanical lug, compression, etc.).

40. What is the specific requirement for replacement / modification / re-integration of the existing Power Monitoring System? There is a monitoring spec included but no relevant SOW, drawings, or description of the existing system functionality. Please provide information on the existing system relevant to the required SOW, as applicable.

Response: Medium voltage single ended switchgear have meters and will have new metering installed in the low voltage lineup, See Specification 25 10 10 Section 2.1 for the meter characteristics. New low voltage switchboards which replace the existing switchboards will also have the same class of meter installed.

41. Does the VA have a copy of the Existing Arc Flash and Coordination study for the entire facility? If not, what is missing?

Response: Information that is available will be provided to the successful Contractor following contract award.

42. A list of buildings that are staffed and operated 24/7 and what ones are closed nights and weekends.

Response: All buildings are 24/7. See A/E phasing plan notes on E-001

43. For the indoor unit sub-stations, the current transformers appear to be standard mineral oil filled. We would typically use an FR3 (high fire rated fluid) for indoor applications. Please confirm which fluid should be provided within the unit substation transformers for this project.

Response: FR3 (high fire rated fluid) would be acceptable. VA to confirm.

44. Do we need to provide the same amount of spare compartments as existing within the new low voltage switchgear?

Response: Yes, the new low voltage switchgear is to match the existing low voltage switchgear with regards to compartments.

45. Who is responsible for operating the MV equipment to isolate / de-energize / energize as needed?

Response: The medium voltage distribution network is owned by the VA. There is no cost associated to de-energize mains. Any connections in manholes will be disconnected by the contractor. Any “throws of the hand” type breaker/switch shall be de-energized by the VA with close coordination with their electric shop.

46. Who is responsible for the cost associated with paying the utility provider to isolate / de-energize / energize mains as needed?

Response: The medium voltage distribution network is owned by the VA. There is no cost associated to de-energize mains. Any connections in manholes will be disconnected by the contractor. Any “throws of the hand” type breaker/switch shall be de-energized by the VA with close coordination with their electric shop.