Plumbing old string inverter through enphase IQ combiner - allowed?

[nuke]

Before I retire my old string inverter and have an entirely microinverter based solution (RSD requirements, california, etc), does anyone know if it's possible to just run the output of the string inverter to one of the breakers in my IQ combiner/envoy box? Obviously the envoy won't be able to do much to communicate with it, but I don't think I can have two backfeeding breakers in my main panel. It also reduces the number of weird extra conduits i'd need to run in the meantime...

 

[shampeon]

Why would you think you couldn’t have multiple solar breakers in your main panel? My Enphase M250 system is on two branches, each on their own breaker into my main panel. Just label all of the breakers so everyone knows they can backfeed.

You really don’t want to share breakers in your subpanel.

 

[nuke]

I wasn't suggesting doubling up on a breaker in the subpanel. Basically, the IQ combiner is a PV aggregation subpanel that has 4 inputs (breakers). 2 of them are in use with 20a breakers, and I have 2 open slots. The whole IQ combiner lands on a single backfeed breaker in the main panel. Rather than have to find another open breaker in the main panel (which at this point would be challenging for reasons) I was wondering if the Enphase IQ combiner would be ok with having a non-Enphase PV source on one of its breakers.

 

[shampeon]

The install docs say you can run multiple a/c branch circuits, and up to 4 PV input breakers. Total amps including the gateway 10A breaker is 90A. So I think you could add the string inverter input breaker, depending on the amps, and be fine as long as you're not exceeding the breaker rating in the main panel. It's just a regular subpanel with some extras built in.

I don't think I'd run the string inverter hot through the Enphase CT, as that would probably throw off the Enphase microinverter generation stats. Keep the Enphase components separate from your string inverter. And I'd probably not connect the string inverter input breaker until after final inspection, just to keep it simple.