NEC and THHN wires in wire tray

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dannyrzk

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I'm not sure I understand art 392.10 of the NEC. I'm running data CAT6 and #10 THHN under a raise floor , and I intend to use a wire basket for the CAT6, but also was looking permission on the NEC to share the same tray with the power cables or at least run another basket side by side. However, NEC 392.10 seem to limit the sizes permitted to run in such environments.

simple question is, can I run my #10 awg, in these wire basket or not?

thank you much
 
dannyrzk said:
I'm not sure I understand art 392.10 of the NEC. I'm running data CAT6 and #10 THHN under a raise floor , and I intend to use a wire basket for the CAT6, but also was looking permission on the NEC to share the same tray with the power cables or at least run another basket side by side. However, NEC 392.10 seem to limit the sizes permitted to run in such environments.

simple question is, can I run my #10 awg, in these wire basket or not?

thank you much
Click to expand...

Are you asking about power conductors or power cables?
 
dannyrzk said:
...simple question is, can I run my #10 awg, in these wire basket or not?...
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Not as single conductor #10 (unless you can magically find some so rated). Use multiconductor Type TC... and assuming these are power circuits they will most likely require a separate tray.
 
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Originally Posted by dannyrzk
...simple question is, can I run my #10 awg, in these wire basket or not?...



Not as single conductor #10 (unless you can magically find some so rated). Use multiconductor Type TC... and assuming these are power circuits they will most likely require a separate tray.


Type TC cable is probably the best solution, but what if the owner wants to save money and just run cable under floor with nor wire-way management of some sort?

Thanks
 
electrofelon said:
Most THHN and XHHW I have run across recently is CT rated (at least in larger sizes, I havent really looked at smaller sizes....)
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It is not rated for CT use in smaller sizes because the smallest single conductor permitted in tray is 1/0 and only in industrial occupancies.
 
electrofelon said:
Well that makes sense :slaphead:
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I know it is the rule, but it makes anything but sense.

If mechanical integrity of the cable in the tray were the issue, there's gotta be a way to solve it for wires smaller than 1/0. Closer rung spacing, securing it with cable ties, etc. And NEC2014 finally came to its senses on this issue in PV applications, by allowing listed PV wire of all sizes in cable trays with secure and support context rules. The tray sizing and ampacity algorithms in such an application are still a blindspot.

If the issue is the chemistry of the insulation, and how it behaves in fires, then I would think that a wire not permitted in a small size, would not be permitted in any size.
 
Carultch said:
I know it is the rule, but it makes anything but sense.

If mechanical integrity of the cable in the tray were the issue, there's gotta be a way to solve it for wires smaller than 1/0. Closer rung spacing, securing it with cable ties, etc. And NEC2014 finally came to its senses on this issue in PV applications, by allowing listed PV wire of all sizes in cable trays with secure and support context rules. The tray sizing and ampacity algorithms in such an application are still a blindspot.

If the issue is the chemistry of the insulation, and how it behaves in fires, then I would think that a wire not permitted in a small size, would not be permitted in any size.
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Prior to the 68 NEC, you were permitted to install single conductors of any size in cable tray...you would have to look at the proposal substantiation to find out why they changed to limit it to 1/0 and larger. I assume that the substantiation showed issues with the use of smaller conductors.
 
dannyrzk said:
Reading all the Threads, it only tells me I have no option but to place then in a separate cable tray.

thank you all
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Not well enough as someone correctly stated you can't run 10 AWG in a cable tray without it being part of a cable assembly based on the size (less than 1/0) and a industrial environment.....but if you happen to run into a PV installation then here you go....;)

690.31(C)(2) -Cable Tray. PV source circuits and PV output circuitsusing single-conductor cable listed and identified as
photovoltaic (PV) wire of all sizes, with or without a cable
tray marking/rating, shall be permitted in cable trays
installed in outdoor locations, provided that the cables
are supported at intervals not to exceed 300 mm (12 in.)
and secured at intervals not to exceed 1.4 m (41∕2 ft).
 
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