Enphase M250 with unirack: electrician says a GEC is still required by HI inspector

[Wilson]

Doing a DIY 36 panel install right now with enphase m250 and unirack rails. Do I still need a separate continous copper ground (#6-8awg) on the entire rail branch? I looked over the enphase install guide and it says no gec is required and the egc is done via the green wire on the enphase cable. My electrican says the hawaii inspectors will still require the gec. Is this true? Thanks!


Wilson

[SunEagle]

Doing a DIY 36 panel install right now with enphase m250 and unirack rails. Do I still need a separate continous copper ground (#6-8awg) on the entire rail branch? I looked over the enphase install guide and it says no gec is required and the egc is done via the green wire on the enphase cable. My electrican says the hawaii inspectors will still require the gec. Is this true? Thanks!


Wilson

If you live in Hawaii there is something you may have to consider concerning who can actually install any of the grounding for a PV system. Apparently there is some contention between the Electrical Workers Local 1186 and the state's Solar Energy Association per the attached article.

http://www.renewablesbiz.com/article/13/12/state-board-defers-decision-who-can-install-pv-systems?utm_source=2013_12_19&utm_medium=eNL&utm_campaign=RB_DAILY&utm_term=D&utm_content=410609

[Wilson]

@SunEagle- Thanks electrician is certified.

Any install Enphase M250 in the US and still installed a GEC (Additional Grounding cable for inverter/Rails)?

[NickSoleil]

A GEC is not required with Enphase M250s

Hi Wilson. We have worked extensively with the AHJs throughout the Hawaiian islands and do not know of any AHJ's that are requiring an additional grounding conductor for the microinverters outside of the ground that is already provided in the microinverter cable.

With the Enphase M250 microinverters, the DC conductors are not bonded to ground, so a GEC conductor is not required. This means that the grounding conductor provided in the Enphase cabling is more than adequate to meet the requirements for grounding of the microinverter. We don't even provide a ground lug on the M250 microinverter.

We have conducted inspector trainings across the Hawaiian islands, and have received a great deal of support from the AHJs. If you know of a particular AHJ that is requiring an additional ground conductor to the microinverters, then please let us know and we will work with them to resolve this. You should be fine, though.

I've attached a technical note that discusses this. M250-with-IG.pdf