Good afternoon!
I have a job where im being asked to change a meter center for an apartment complex to a wireway / disconnect arrangement due to lead times. Unfortunately, im having to do this with most jobs these days. However, the EC drew a sketch with this request based on field conditions, and the request was one I haven't came across before in the past. Generally, when I haven't something before, I always like to question it.
The service is 1200A single phase fed via 4 sets #500 kcmil Al. For whatever reason, the EC wants to feed the 1200A disconnect, and then come out of the 1200A with 4 sets, BUT, wants to feed two different wireways with 2 sets of #500 kcmil Al (ie. two parallel sets to each respective wireway).
My immediate thought was that this would not be code compliant because Parallel conductors need to be identical in length and routing, etc. However, they sort of are (respectively, per set). Next, I thought this would be sort of like a tap, but im not sure thats the case because the conductors are full size. However, perhaps it is a tap because (2) Sets of #500 kcmil is good for 620A, which is far less than the 1200A OCP.
Obviously, the respective phases would be out of balance but other than that, I can't think of why this wouldn't be compliant other than the reasons I mentioned.
Putting load calculations aside, has anyone seen or done this before? Or, have a relevant code section?
BASIC DIAGRAM ATTACHED
I have a job where im being asked to change a meter center for an apartment complex to a wireway / disconnect arrangement due to lead times. Unfortunately, im having to do this with most jobs these days. However, the EC drew a sketch with this request based on field conditions, and the request was one I haven't came across before in the past. Generally, when I haven't something before, I always like to question it.
The service is 1200A single phase fed via 4 sets #500 kcmil Al. For whatever reason, the EC wants to feed the 1200A disconnect, and then come out of the 1200A with 4 sets, BUT, wants to feed two different wireways with 2 sets of #500 kcmil Al (ie. two parallel sets to each respective wireway).
My immediate thought was that this would not be code compliant because Parallel conductors need to be identical in length and routing, etc. However, they sort of are (respectively, per set). Next, I thought this would be sort of like a tap, but im not sure thats the case because the conductors are full size. However, perhaps it is a tap because (2) Sets of #500 kcmil is good for 620A, which is far less than the 1200A OCP.
Obviously, the respective phases would be out of balance but other than that, I can't think of why this wouldn't be compliant other than the reasons I mentioned.
Putting load calculations aside, has anyone seen or done this before? Or, have a relevant code section?
BASIC DIAGRAM ATTACHED
