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

[Christopher Warfel]

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