Service Disconnect Question for Solar PV system

jcpanchal

New User
Location
New Jersey
Occupation
Solar PV Installation Company Owner
Hello Everyone:

When line taps are used to connect solar PV system with grid, what type of disconnect can be used?

As per NEC Article 690.13(C) it must be 'Service Disconnect'

we have to use service disconnect and SER conductor for solar PV systems.

Please let me know if you consider following as service disconnect in compliance with NEC section 690.13(c)

https://www.electricallicenserenewal.com/Electrical-Continuing-Education-Courses/NEC-Content.php?sectionID=382.0

1. AC disconnect fused or non-fused 60 amps

https://www.homedepot.com/b/Electrical-Power-Distribution-Disconnects/N-5yc1vZbm0h?Nao=24&Ns=None&storeSelection=961,933,6911,949,926&experienceName=default

2.
QO200TRNM 60A

https://www.amazon.com/Square-Schneider-Electric-QO200TRNM-7-5-Kilowatt/dp/B002YEN8YK/ref=psdc_6369371011_t2_B07PS6BXLR


Please advise.

If not please advise which can be service disconnects.

Thanks

Jay
 

jaggedben

Senior Member
A disconnect must be labeled 'Suitable for use as service equipment' to be used as such. I very much doubt that the ones you've linked to are suitable. They are intended for use with air conditioners and such and will not have the interrupting ratings required for service equipment. I also don't beleive pull out type disconnects qualify anymore. You should be looking for a fused saftey switch type disconnect.
 

Carultch

Senior Member
Location
Massachusetts
Be careful about what AC means. It could mean alternating current or it could mean air conditioning.

An "air conditioning disconnect" is intended to be used at the level of the air conditioning device (e.g. condenser/compressor). You might be able to use an "air conditioning disconnect" as a 690.15 maintenance disconnect for an inverter, but it is not "suitable for use as service equipment" that would qualify you to use it as the first disconnect from the service conductors, for a line side interconnection. I would recommend avoiding the pull-out style disconnects for anything other than their intended air conditioning application.

"Suitable for use as service equipment" generally has to do with the fault current rating that the device can withstand, and that it gives you a designated method to bond the neutral to the ground with the jumper screw. It is in the gray area, for whether this disconnect counts as a "service disconnect" or not. In any case, it needs to carry the "suitable for use as service equipment" rating, when used for a "line side tap". Ultimately, it depends on the opinion of the AHJ, and there is no prevailing consensus or NEC rule to clarify it. Some AHJ's require you to build it exactly as if it were a service disconnect, while others may require you to isolate neutral and ground in it, and run your neutral and ground to the already-established neutral and ground for the premises wiring.

Most blade-style safety switches that are fusible, will be suitable for use as service equipment. The unfused safety switches do not carry this rating. An example Square D's part number is as H222NR. The breakdown of this part number establishes the poles/volts/amps, the NEMA enclosure rating for its environment, the presence of a neutral, fused/unfused, and general vs heavy duty.
 
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