buss duct pricing:Need a rough cost per foot for 2500A Bussduct.

[fenec]

I need to locate a 2MVA transformer as near as possible to the switchgear it serves. Per PG&E, a 2500A service requires bussduct when the distance between the secondary spades of the transformer and the switchgear exceeds 50 ft. The problem is that the only spot where the transformer can be within 50 ft of the switchgear cannot be accessed by PG&E vehicules. This means the only option is to relocate the transformer beyond the 50 foot distance where it can be accessed by PG&E vehicules and having to use buss duct up to the switchgear. If buss duct is the only option in this case, how can I minimize cost?? any suggestions??

 

[MDom]

Fenec, to minimize cost you can :
1. Use aluminium busduct instead of copper
2. Try to aviod elbow element as well as any flexible or any non-straight.
3. Chesk the number of conductors whether is it possible to use 3 conductor instead of 4.
The manufacturers have two main technologies - sealed (compact type) of busduct for example Canalis KT of Telemecanique or busduct with air gap between the phases
(Canalis KH) The last is approx 30% cheaper.
B.r.

 

[RonShap]

List price for GE AL 3ph, 4W 2500A feeder busway 10' long is $5000, you then have to add all fittings, etc.
$7000 for the equivelent in CU.

 

[brupp]

Since you say a 2MVA transformer we'll assume you're talking low voltage, 480V or similar. I would agree with recommendations above to use aluminum busway, not nonsegregated phase bus duct. It is smaller, less expensive, and simpler to disassemble if you need to do so.

I agree with RonShap on costs. Although there should be some savings for a long straight run. Remember to include costs for supports.

One big word of caution. Busway is far more likely to be assembled incorrectly than nonseg bus duct. The joints can be very easily misaligned, insulation wedged between layers of conductor, enclosure material installed between the insulation and the conductor, etc. If you use busway, inspect all joints closely and test it carefully. On one plant we had about 80% of joints with some type of installation error when we inspected and tested at commissioning time.