[RE-wrenches] Will IQ8 microinverters backfeed a generator during grid interruptions

[scot.arey at solarcentex.com]

MI = microinverter

Howard "Scot" Arey
Owner, Solar CenTex
254-300-1228

________________________________
From: RE-wrenches <re-wrenches-bounces at lists.re-wrenches.org> on behalf of Christopher Warfel via RE-wrenches <re-wrenches at lists.re-wrenches.org>
Sent: Thursday, January 22, 2026 6:43 AM
To: scot.arey--- via RE-wrenches <re-wrenches at lists.re-wrenches.org>
Cc: Christopher Warfel <cwarfel at entech-engineering.com>
Subject: Re: [RE-wrenches] Will IQ8 microinverters backfeed a generator during grid interruptions


Hi Scot, I am not familiar with the term MI, what does it mean?  Thank you, Chris



On 1/21/2026 12:07 PM, scot.arey--- via RE-wrenches wrote:
Good day,

I many years ago watched the fast-switching capabilities of the IQ-8 microinverters to produce only what demanded of the MI, and wondered if it might have application in a grid-tied system that is served by a whole-house generator.

We have the opportunity to install grid-tied-only array of 24 IQ8 but all the MIs will be on the customer side of an auto-transfer switch and generator. We want to leverage using existing building wiring to carry the solar and all solar sizing meets the 120% rules.

But I know that grid-tied solar on the customer load-side of the transfer switch means no place for full solar power production to flow to when the grid is not available...but  then I thought back to that fast switching capability: is there a way to ensure the IQ8 don't backfeed a generator when it is operating for a grid anomaly?

I suspect the answer is "are you nuts???" but that video of capability got me thinking, "why not?" and if not, how is it - what tells the MI to cease production? - when it is within a full and proper ISC/ESS system design?



Howard "Scot" Arey
Owner, Solar CenTex

NABCEP PV Installation Professional
TECL 29755
254-300-1228
[cid:part1.eLWTUprU.iJIHgygU at entech-engineering.com]




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--
Christopher Warfel, PE
ENTECH Engineering, Inc.
PO Box 871, Block Island, RI 02807
(401) 447-5773
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