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Posted By: frodo Cable Trays - 05/19/01 12:23 PM
given a 24" cable tray that contains only 500mcm stacked in layers what is the violation there?

twelve 500mcm cables are distributed across the bottom of the tray...ladder type...on top of those is another layer.

as i read the code it doesnt allow for this.

given the addition of multi-conductor cables it gets even more restrictive.

thanks for any input
Posted By: golf junkie Re: Cable Trays - 05/20/01 01:24 AM
OK Frodo,
I'm bored and no one else has answered, I'll bite.

318-10(1) seems clear with no provisions for exceptions.

Single conductor cables, 2000v or less,

(1) Where all cables are 1000kcmil or larger, the sum of the diameters shall not exceed the cable tray width.

GJ
Posted By: golf junkie Re: Cable Trays - 05/20/01 01:29 AM
If the voltage is over 2kv, (this is a powerhouse, right?)
then 318-12 and 318-13 are even more restrictive.
Posted By: golf junkie Re: Cable Trays - 05/20/01 01:32 AM
It's Saturday night and I'm digging thru the NEC and posting at ECN........

man, I gotta' get a life. [Linked Image] [Linked Image] [Linked Image]
Posted By: frodo Re: Cable Trays - 05/20/01 02:31 AM
Quote
Originally posted by golf junkie:
It's Saturday night and I'm digging thru the NEC and posting at ECN........

man, I gotta' get a life. [Linked Image] [Linked Image] [Linked Image]

yeah its sat night and being away from home is about as bad...

yes it is a powerhouse...but the voltage is 480vac...

the contractor is not even attempting to follow the nec on the job...

there are a lot of violations around....this is one that i really wanted to be sure on so i figured i would ask for some opinions..they have stacked a couple layers of 500MCM conductors in a 24" tray and i think they are planning on dumping some control cables in there as well as some multi-conductor power cables...3/C 12, etc...

ge requires that the nec be followed if it is on our equipment even if it is a powerhouse...i have never seen a job where the nec was not recognized..

pictures available

thanks for the input
Posted By: frodo Re: Cable Trays - 05/20/01 03:10 AM
Quote
Originally posted by golf junkie:
OK Frodo,
I'm bored and no one else has answered, I'll bite.

318-10(1) seems clear with no provisions for exceptions.

Single conductor cables, 2000v or less,

(1) Where all cables are 1000kcmil or larger, the sum of the diameters shall not exceed the cable tray width.

GJ

don't you mean 318-10 (2) 500mcm are smaller than 1000kcmil i thought?

i was thinking 318-8, 9 & 10 covered it pretty well, indicating that you can not stack single conductors except for grouping?
Posted By: golf junkie Re: Cable Trays - 05/20/01 03:35 AM
Frodo,
You're right....
I had confused the conductor size with your post on seal offs.

My bad.

GJ
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