Using SRML wire rather than THHN

[LHarrington]

Good afternoon,
Have any of you used SMRL wire rather than THHN in equipment installation?
My local supply house sells this cheaper than THHN. I have included an example:

We are planning for the addition of Three addition lasers soon each of these machines have a full load draw of 130 amps each, THHN would be a #1 or an 1/0 for the load. On the other side SMRL wire a #4 is rated for 180 amps. Each run is under 100 foot. I like working with SMRL because of it flexibility and the smaller diameter. We have several places in the facility that electricians before me have used it but not sure if it's the correct procedure. Driving this is limited space in the concrete wire troughs with the THHN we need to have 2.5" to 3" conduit for the 9 load leads and three grounds. If I stay with the SRML wire I can stay with in 2" conduit saving me time and headaches. However I want it to be right.

Thank you in advance
LHarrington

 

[iwire]

Is this an NEC installation or not?

If it is under the NEC you have to use a conductor from Table 310.13

If that 4 AMG carrying 180 amps is connected to any equipment covered by the NEC it will be too hot to terminate.

 

[bbaumer]

iwire is correct, imo.

110-14(C). Unless you have very high temp rated terminations on your equipment, which is unlikely, it doesn't matter what the temp rating is on the SRML.

 

[charlie]

Equipment manufacturers may use bailing wire if they so desire and a NRTL agrees with them. Have you ever noticed #12 Cu. with 105?C insulation for the internal wiring of a 4500 watt water heater (cold, not hot)? You are required to run #10 Cu. to the water heater since #12 will not cut it.

The bottom line is that field wiring shall be done under the prescriptive rules of the NEC. Equipment wiring is done to the UL performance standards in any manner the manufacturer wishes it to be done as long as it passes muster with the NRTL. Manufacturers will normally meet NEMA Standards as well. :smile: