Solaredge glitch

[sensij]

My SE3000A-US inverter has been in operation nearly two years. Yesterday, I shut it down to work on the networking and when I powered it back up, it wouldn't produce any AC power. All 12 optimizers reported P_ok, the AC voltage and frequency were good and the DC voltage was initially good, but fell down to safe voltage levels (~1.1 V per optimizer). I tried a variety of reboots, but nothing worked.

I had shut the system off by first turning the rotary disconnect, a bad idea when the system is actively producing power. The recommended shutdown procedure is to toggle the safety switch to the off position first, and once the voltage is at a safe level, other disconnects can be used.

I submitted an online support ticket yesterday, but with no response after 24 hr, I called in for help this morning. They directed me to re-pair the optimizers, which restored the inverter to normal operation. Only cost me about 15 KWh of production, $3 for a cheap lesson learned.

[SunEagle]

Glad you got your system working again.

Maybe working on a solar pv system at night makes more sense in the long run.

[bcroe]

Maybe working on a solar pv system at night makes more sense in the long run.

Good idea, happens a lot here. There a few AC outlets on the array for work lights, etc. Bruce Roe

[sensij]

The SolarEdge inverter shuts down at night, most of its functions are only available when there is enough sunlight to wake it up.

[SunEagle]

The SolarEdge inverter shuts down at night, most of its functions are only available when there is enough sunlight to wake it up.

So I guess there is a proper procedure to work on the system "hot" without accidentally shutting it down like you did.

[sensij]

So I guess there is a proper procedure to work on the system "hot" without accidentally shutting it down like you did.

Right. That is why I posted the correct sequence above, made bold now for emphasis... it wasn't obvious to me from the manual, although I should have thought it through electrically. On machines I build I force the motor drives to power down before any of the current carrying conductors are disconnected (when it is safe to add that slight delay), and the same process seems to be appropriate for this type of inverter as well. The failure mode here is apparently in the communication logic used by the optimizers, such that re-pairing them resets it, but aside from that, it is still poor practice to disconnect a conductor carrying current if a method to shut it down first exists.

[SunEagle]

Right. That is why I posted the correct sequence above, made bold now for emphasis... it wasn't obvious to me from the manual, although I should have thought it through electrically. On machines I build I force the motor drives to power down before any of the current carrying conductors are disconnected (when it is safe to add that slight delay), and the same process seems to be appropriate for this type of inverter as well. The failure mode here is apparently in the communication logic used by the optimizers, such that re-pairing them resets it, but aside from that, it is still poor practice to disconnect a conductor carrying current if a method to shut it down first exists.

Got it. Thanks for the clarification. I hope others read and follow your logic.

[cebury]

I followed the logic. Thanks for the info, I'm sure I'll need to use it someday.

IOW: use the little power toggle switch under the inverter first, then the big black Rotary On/Off switch located on the DC Safety switch.

[bcroe]

Right. That is why I posted the correct sequence above, made bold now for emphasis... it wasn't obvious to me from the manual, although I should have thought it through electrically. On machines I build I force the motor drives to power down before any of the current carrying conductors are disconnected (when it is safe to add that slight delay), and the same process seems to be appropriate for this type of inverter as well. The failure mode here is apparently in the communication logic used by the optimizers, such that re-pairing them resets it, but aside from that, it is still poor practice to disconnect a conductor carrying current if a method to shut it down first exists.

That is my practice as well; opening a switch running near capacity will considerably shorten its life. Sometimes I have shut
down a string or 2 at night, then come back and worked on them in daylight. In the case of moving 36 panels to provide a
snow gap, it was all done late at night after the necessary holes were drilled that day.

If a system must be shut down when operating, I open the inverter AC breaker first. With no DC current flowing, I can open
the DC disconnect or string fuse without damage. I have quickly CLOSED a string fuse contact when hot, to avoid losing the
rest of the days production. When I find it welded, I'll stop doing that too. Bruce Roe