Bad M250 or bad panel or ???

[Coyotefred]

I have a single Enphase M250 in my array with no production. I thought it might be the panel (I’ve had trouble with a few others from the same person I bought this one from) so I switched out the junction box, but still no production. I’ve attached a graph from Enlighten with the microinverter’s performance the last few days. Normal AC voltage getting to it. Normal DC voltage for this panel (around 30-35v), but the weird display for DC current (the pink line)…basically only showing 0-.01A. So I go up to the panel with my multimeter and measure across the leads and confirm the DC voltage. But my meter is reading normal current—around 6-8A yesterday. I check the connections and disconnect/reconnect the M250 and it shows its normal sequence…solid green light and then eventually flashing green light—although one of the times I did this it flashed me 6 green flashes in quick succession…not sure if this indicates anything or not. On the Envoy I’m showing 14 devices (all of my M250s including this problem one), but only +13 web. The M250/panel shows up as you see in the picture, with the little error “flag” that brings up the “Production Issue” error popup.

Any idea what my issue might be? I’ve e-mailed Enphase a couple of times now but received no response. Thanks for your time.

[Naptown]

What is it doing after the 6 green flashes.
It takes a full 5 minutes to start up.
Orange is no communication with envoy but producing power.
Red is a low resistance fault and can be cleared per the instructions that should have been left with you in the operators manual

[SunEagle]

That pink DC current plot reminds me of a very larger pv system inverter that would just stop producing and then 5 minutes later reconnect again. We found that one of the "anti island" safety limits (phase shift imbalance) kept getting exceeded so the inverter would go off line and then after 5 minutes (per the program) check for the problem and if all was ok it would start up again.

We fixed this particular problem by extending the "phase shift imbalance" sensing time. The problem was something on the grid that was happening but very fast so extending the sensing time made the inverter less sensitive to this issue without eliminating the safety interlock.

I am not sure if what I ran into is happening to you but it does look like that panel shuts down for brief periods during the day even though it is being "seen" by the Envoy.

[Coyotefred]

It is showing the normal green flashing (green flash every 5-10 seconds). I've not seen the orange or red indicator on this M250 yet. That's one of the things that is strange. Everything is looking like it "should" but I'm getting no production--or at least the Envoy via the inverter isn't showing any. I wish I had an extra M250 sitting around to swap in and try but right now I don't.

What is it doing after the 6 green flashes.
[snip]
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[Coyotefred]

Hi, and thanks for your response. I'm not sure I followed everything you've said here. All I can say is what the Envoy is "seeing" is 0w production 24/7. There is no period showing up where even a watt was produced (or at least detected by the Envoy).

That pink DC current plot reminds me of a very larger pv system inverter that would just stop producing and then 5 minutes later reconnect again. We found that one of the "anti island" safety limits (phase shift imbalance) kept getting exceeded so the inverter would go off line and then after 5 minutes (per the program) check for the problem and if all was ok it would start up again.

We fixed this particular problem by extending the "phase shift imbalance" sensing time. The problem was something on the grid that was happening but very fast so extending the sensing time made the inverter less sensitive to this issue without eliminating the safety interlock.

I am not sure if what I ran into is happening to you but it does look like that panel shuts down for brief periods during the day even though it is being "seen" by the Envoy.

[SunEagle]

Hi, and thanks for your response. I'm not sure I followed everything you've said here. All I can say is what the Envoy is "seeing" is 0w production 24/7. There is no period showing up where even a watt was produced (or at least detected by the Envoy).

I misunderstood you. So there is something that is telling your system the panel is there but no info on how much if any it is producing.

I am not sure what it would take to swap out that M250 with another one or swap panels or swap "drop lines" from the M250 to a different trunk line connection. I know that it can be hard to identify what the problem is without being able to see if the problem "moves" or stays.

What about contacting your installer or someone familiar with your system?

[Coyotefred]

That installer would be me I installed this system myself as I did with another Enphase-based system at my previous home. I've always had great luck with the Enphase microinverters and for that matter solar panels, which I usually get in small batches when I can afford to add a few more from eBay, etc. But this last batch from one eBay seller has given me issues and I've had to repair/replace the junction boxes on a couple of other panels. This solved the problem for the others, but this last panel/inverter is still not working and has me stumped... So hoping one of the people here more knowledgeable than me can help

[snip]

What about contacting your installer or someone familiar with your system?