Cable Tray
- Thread starter pete m.
- Start date
- Status
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
Do you make a distinction between single conductor and individual conductor? An individual conductor may be part of a multiconductor assembly.
If the cable tray were in an industrial setting 392.3(B)(1) would allow a single conductor cable of 1/0awg or larger. I find no similar verbiage for a cable tray that is not in an industrial setting (such as in the warehouse of a distribution company).
I have seen cable tray installed in such a facility and I am wondering where in 392 was it permitted. If it is permitted where would I find provisions in the NEC that governs this type of installation i.e. minimum wire size, ampacity, tray sizing, etc..?
Pete
See 392.4 for uses not permitted.
Single conductor cables are not permitted in any establishment other than industrial.
Minimum wire sizing other than single conductor in industrial installations is determined by the respective wiring method used and purpose. See Table 392.3(A).
Ampacity and tray sizing is as per other sections of 392... and there are many variables to consider.
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
S$ made an excellent summary.
As far as I'm concerned, I would avoid single-conductor cables in cable trays all together except it starts getting impractical to use multi-conductor cable much over 1.5" in diameter. But the Code is greatly remiss in stating support/securing requirements for single-conductor cables. (I've already made that Proposal twice and won't again since I do know how to do it correctly, but just wait for the first fault to see why securing single conductor cables properly is critical.)
As far as I'm concerned, I would avoid single-conductor cables in cable trays all together except it starts getting impractical to use multi-conductor cable much over 1.5" in diameter. But the Code is greatly remiss in stating support/securing requirements for single-conductor cables. (I've already made that Proposal twice and won't again since I do know how to do it correctly, but just wait for the first fault to see why securing single conductor cables properly is critical.)
- Status