francis.key19
Member
- Location
- frederick, md
Hi,
I have a contractor who is running paralell feeders (3/0) for us on site. The service is for a 600HP drive, 3 phase, 4 wire. The route is to use the first 120ft of an existing ladder tray, then the remaining 30ft will be 4" conduits. They ran 2 (two) 4" conduits, instead of 3. Several questions concerning this installation. Contractors said the installation is proper and followed codes.
1. Should there have been 3 conduits where in each one, we should have A,B,C, N and Ground conductors?
2. I only see one ground 3/0. Contractors said only need one since most the distance are in the tray. What if there is a short in the conduit?
3. Since the cables will be in open air on tray then in conduits, how should the conductors be derated?
Lastly, this contractor took 7 days for the installation with 3 people. This seems a little bit much for this work. The tray is existing, and conduits are ran in open area 16ft elevation. Any idea how long this work should typically take?
Thanks.
Francis.
I have a contractor who is running paralell feeders (3/0) for us on site. The service is for a 600HP drive, 3 phase, 4 wire. The route is to use the first 120ft of an existing ladder tray, then the remaining 30ft will be 4" conduits. They ran 2 (two) 4" conduits, instead of 3. Several questions concerning this installation. Contractors said the installation is proper and followed codes.
1. Should there have been 3 conduits where in each one, we should have A,B,C, N and Ground conductors?
2. I only see one ground 3/0. Contractors said only need one since most the distance are in the tray. What if there is a short in the conduit?
3. Since the cables will be in open air on tray then in conduits, how should the conductors be derated?
Lastly, this contractor took 7 days for the installation with 3 people. This seems a little bit much for this work. The tray is existing, and conduits are ran in open area 16ft elevation. Any idea how long this work should typically take?
Thanks.
Francis.