Micro-inverters

[Adogg]

I was wondering if anyone on this site has experience in photovoltaic installations. The question I have is in regards to a micro-inverter system. What are the requirements for means of disconnect for this type of system? With a "traditional" system we typically run our DC conductors off of the roof in EMT and to the basement where the first disconnect is installed for the DC array. This is the first system of micro-inverters that we are installing and a coworker and I had disagreement about where we are required to install means of disconnect.

the following is a link to the micro-inverters product page:
http://www.enphaseenergy.com/products/products/micro-inverter.cfm

Please cite any code articles.

 

[ty]

I was wondering if anyone on this site has experience in photovoltaic installations. The question I have is in regards to a micro-inverter system. What are the requirements for means of disconnect for this type of system? With a "traditional" system we typically run our DC conductors off of the roof in EMT and to the basement where the first disconnect is installed for the DC array. This is the first system of micro-inverters that we are installing and a coworker and I had disagreement about where we are required to install means of disconnect.

the following is a link to the micro-inverters product page:
http://www.enphaseenergy.com/products/products/micro-inverter.cfm

Please cite any code articles.

Have you looked at 690 at all? In particular 690.15 and 690.17
also have you at least watched the enphase video here: http://www.enphaseenergy.com/products/moreinfo/trainingvideo.cfm

 

[Adogg]

Yes, I have read 690 and watched the instructional video.
I assume these micro-inverters are subject to the requirements of 690.14(C) and (D). The instructional video suggests to use switches mounted in weatherproof boxes on the end of the mounting rail which would meet the requirements of 690.14(D)(2), but 690.14 (C)(1) requires the disconnect to be in a readily accessible location. I don't think these switches would comply with that requirement in a roof mounted application.

 

[drive1968]

I recently installed an Enphase micro-inverter system. You are correct that the switch on the roof doesn't count towards the readily accessable requirement. The 15 AMP backfed breaker counts toward that purpose. That is the reason my local jurisdiction doesn't allow the backfed breaker to be inside the garage on the subpanel, but requires that it be on the main panel accessable from the outside of the house.

 

[ty]

I don't think these switches would comply with that requirement in a roof mounted application.

correct...