lexkyphil
Member
- Location
- Lexington, Kentucky
Gentlemen: I have a client who has asked me to provide the following design for an industrial installation:
a. corrugated bottom mill galv steel cable tray, with a solid flat top.
b. underground rigid conduits coming from a n. gas compressor, rising on the outside of an MCC building, coming thru wall to terminate thru side rail of tray.
c. thwn conductors of sizes ranging from #12 single cond, up to 1/0 thwn single conductor.
d. open cables route thru tray a short distance, then leave the tray in rigid conduits and drop down to the top of a motor control center.
I personally think this is a tedious and inadvisable way to run this wiring and it may not meet the code. It seems that they want to use the cable tray, ignore the wiring method restrictions of 392 and instead call the tray a metal wireway, as in article 376. I do want to give the customer what he wants, but if it puts my design in danger of being questioned or rejected by an inspector, I obviously don't want to be in that position. Even if the client tells me to do this, I will be the one holding the bag when it is a problem in the field. I would like your opinions that are informed by your experience.
Thanks in advance for your help.
a. corrugated bottom mill galv steel cable tray, with a solid flat top.
b. underground rigid conduits coming from a n. gas compressor, rising on the outside of an MCC building, coming thru wall to terminate thru side rail of tray.
c. thwn conductors of sizes ranging from #12 single cond, up to 1/0 thwn single conductor.
d. open cables route thru tray a short distance, then leave the tray in rigid conduits and drop down to the top of a motor control center.
I personally think this is a tedious and inadvisable way to run this wiring and it may not meet the code. It seems that they want to use the cable tray, ignore the wiring method restrictions of 392 and instead call the tray a metal wireway, as in article 376. I do want to give the customer what he wants, but if it puts my design in danger of being questioned or rejected by an inspector, I obviously don't want to be in that position. Even if the client tells me to do this, I will be the one holding the bag when it is a problem in the field. I would like your opinions that are informed by your experience.
Thanks in advance for your help.