Brandon Loyd
Senior Member
Are there any exceptions for protecting wire when feeding a surge suppresor? I found a 60 amp 3 pole breaker feeding a surge suppresor with #10 wire. Looks like a violation to me.
Conductor protection
- Thread starter Brandon Loyd
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jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
me too. nothing in T240.3 about surge suppressors.
Twoskinsoneman
Senior Member
- Location
- West Virginia, USA NEC: 2020
- Occupation
- Facility Senior Electrician
It's a good point. If the SS is factory wired with a certain awg, and the instructions with the SS call for it be installed on a certain rated OCPD, there should not be a violation.
renosteinke
Senior Member
- Location
- NE Arkansas
Surge suppressors are supposed to be installed as close to 'the source' as possible. Could this be an instance where tap rules can be used?
Brandon Loyd
Senior Member
The wire is field install from the breaker to termination points in the TVSS. Conductor length is less than 10'. Don't know what the manufacturer asks for as far as OCP. But to my knowledge, manufacturers cannot supersede code anyway. So would you all agree this is in violation?
- Location
- Connecticut
- Occupation
- Engineer
I don't feel that this is a violation, but the code is certainly not clear.
The best I could offer is 240.4(A).
There is no load on the conductors, so there is no way to size the conductors per Art 210 or 215. 285.24, for instance, says that a Type 2 SPD shall be connected anywhere on the load side of the service OCPD, and 285.26 says the conductors shall be #14 copper minimum. Together these sections suggest to me that I can use #14 awg to connect a TVSS directly to the load terminals of a (any size) Main C/B (assuming the lugs are rated for the multiple conductors.)
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Look up the tvss specs on the manufacturer website. This install may be appropriate. I'm sure I have seen them landed on main lugs of 200 and even 400a. panels with the factory pigtails of 12awg. Otherwise, in your case, whoever installed it was lazy and instead of installing the proper breaker, just used an available breaker that was already in the panel.
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