Solaredge zero output

[Worcester]

Anyone else had this problem?

Client rang last week to say his system hasn't been generating since September (duh....)

Attended site, 8V off the panels (2kw - 8 x 250W east / west split)
Power Ok to inverter, checked the fuse as per Solar edge instructions - appeared to be 'blown'
so replacement inverter sent out, we installed it last Friday, seemed fine, generated Saturday, then nothing today, and nothing displaying on the inverter - guess is fuse blown again

Question is WHY? anyone any ideas?

We'll attend site again Monday to identify actual fault, however it's frustrating for both us and the client. (and costs ££)

 

[whinmoor]

How was it working until last September? Isn't 8 optimisers the bare minimum on SE so the total system sounds a bit under-powered even on the SE2200? Surely that makes it less likely the fuse (or anything else) would blow!?!

We've only done 8 panels with an SE2200 once and we used BenQ 325s. (That was an e/w split on a garage.) Even that shows poor returns on dull days and occasionally fails to start at all whilst our systems with more panels are generating.

You can set up the online monitoring to send an alert if/when the system fails. But, you do end up with false alarms such as snow or the householder switching off his router, etc.

We've only had one SE failure and it was an SE3500 - replaced under warranty. SE Helpdesk sent us their "Non-Responding Inverter's Procedure" which didn't help in our case. The photos in the "Procedure" bore no resemblance to the inside of our inverter!

I can only suggest the usual things which you've probably already checked. Grid voltage ok and stable? Decent 4mm or 6mm cable? Checked cabling for damage? 16 amp breaker? If it's not on a mini-CU, is it worth moving it to one in case another circuit is somehow interfering?

It sounds like the DC side is fine (unless the cold weather is pushing up the voltage too high but that seems impossible). The problem must be on the AC side.

Let us know the outcome and solution.

 

[Worcester]

Thanks Whinmoor, done all the above! And yes the "Non-Responding Inverter's Procedure" is a joke!

When it stops producing it doesn't start again, yesterday bright sunny day, no output..

There is nothing on the inverter screen at all - the screen is 'dead'

 

[whinmoor]

Our 8 panel system only produced 1.65kWh yesterday. That's 2.60kWp.

A 12 panel system (3.12kWp) about a mile away generated 8.97kWh.

There have been two days so far this year when the 2.6kWp failed to produce anything. Some of that will be down to orientation and shading...if one optimiser decides to have a "duvet day", the others remain inactive as well!

 

[Worcester]

..if one optimiser decides to have a "duvet day", the others remain inactive as well!

Really - I wasn't aware if that so if one optimiser doesn't get enough to trrigger it to generate, then the wholes system gives zero output?

I went solar edge as I thought it a better solution than micros, perhaps I was wrong in this instance?...

 

[whinmoor]

I think that's the case on an 8 panel system. Because you'd then be down to 7 which isn't enough for the inverter to operate.

If you have 12 optimisers and one goes on strike, the system will work with just 11.

That's my reading of the data sheet anyway. It says "minimum string length - 8".

I ruled a failed optimiser out as you stated you'd correctly measured 8vDC.

Did you set up online monitoring? Were there any strange readings for the single day the replacement inverter worked?

 

[Worcester]

It was late of an evening when installed, so didn't get the chance to reconfigure the monitoring before it stopped again, we offered the client to attend within 24 hours, it wasn't 'convenient for him', so he'll now have to wait until it's convenient for us... could do with some sun though! (0.4kWh from our own mix and match 4kW system today 1.6kWh yesterday and 12kWh on Sunday )

 

[Worcester]

Back on site today, despite it being overcast and rainy. 8.08 V from the optimsers, inverter pushing up daisies again with another blown fuse.

Discussions with SolarEdge on the phone
"Is it a remote location" - Well yes (for gloucestershire) in the middle of the forest of dean, miles from any other habitation, and at the end of the overheads.
"Do they get frequent power cuts", Yes, see previous answer,
"Ah well, it may be due to surges on the line as the equipment comes back on, we only every see two inverters go on the same site with the fuse blown in rural locations due to the variability of the grid, the fuse has done it's job, another inverter is on its way to you.. and we'd like you to fit some surge protection for the inverter"

Discussed the possible issue of <8 optimisers, and they were confident it should work with 7, probably not with 6, so if two heavily shadowed, it won't start producing.

Good customer service, though still concerned about whether it will blow again, meantime, we've used these quite frequently in other environments to protect pc and high end audio equipment: Surge Protection Devices Ltd - protection of sensitive electronic equipment from damaging over-voltage surges including lightning

 

[SibertSolar]

Type2 DC SPDs with a decent operating voltage would probably be a better idea Gordon, something like these are an easy retrofit

 

[Worcester]

Hi Andy, It's the AC side they want to protect, with the optimisers in place I'm not sure how/if that cube would work on the DC side anyway ??

 

[SibertSolar]

Ah, the AC side, of course, apologies! Plenty of DEHN options there too though, give me a shout if you want details. (The cube works with a handy X-type or Y-type pre-assembled/moulded splitter cable, so you can retrofit the units just by unplugging existing string input and connecting the DEHN device in parallel)