Some Solar Panels not connected

Enterprise1994

Over a month ago we had 16 solar panels installed by ****** for electricity production. Looking at the Soliscloud app the system seems to be split into two strings PV1 and PV2. PV1 has always shown the Voltage, Current and Power as 0.

Luckily we noticed this shortly after install and got in contact with the company straight away. They arranged for a technician to call out 2 weeks later. After the 2 weeks they claimed there was no record of any technician being scheduled and it would be at least another 2 weeks.

We were never provided with any diagram of the system, so I'm not sure if PV1 is meant to be connected, but the company did say it seemed strange PV1 wasn't producing anything. It is a 6.5 kWp system, does anyone know if these 16 panels would indeed be set up as two different strings? Or could all 16 be on PV2? On average the system is producing 7 kWh per day, on a day with complete sun it managed to produce 13 kwH. I have no idea if this is normal but it seems on the low side. They are on a low pitched roof pointing South west with direct sunlight from around noon onwards.

Any help or advice would be appreciated as we don't seem to be getting anywhere.

conor_mc

16 panels on one string sounds a bit nuts tbh. Generation looks low too, I suspect you’re right and your second string isn’t connected up properly.

Marty Bird

OP I’ve 14 panels and I’m getting around 30kwh per day the last few sunny days we had. Looks like it’s definitely one not connected.

Enterprise1994

Thanks everyone for the information. I'm surprised the installer didn't check to see if PV1 was showing any current, voltage etc. before they left. Hopefully the company will send out someone soon as we will have missed out on a month of prime production. It seems like they only have one team who are travelling around the south and west of the country for two weeks and can not come any sooner. In the meantime we were promised a callback on the phone from a technician today as well which never happened. The last few days better not have been the entirety of the Irish summer 😁

graememk

Modnode : No Naming installers, have edited the post.

But yeah, thats one of the basic checks, Check voltages are reaching the inverter.

10-10-20

On the basis of voltage alone it's highly unlikely that all 16 are installed on one string as the average open circuit voltage for panels is generally around 45v (some a low as 39v) and 45 * 16 = 720v - which is much higher than the normal MPPT input voltage range which is typically up to ~600v max. So yeah, two strings.

Buffman

Can you get to the inverter easily for a photo? It will be fairly obvious if one string isn't attached. Do you have the inverter and panels make/model numbers available?

Enterprise1994

https://www.boards.ie/discussion/comment/122137324#Comment_122137324

According to the app, it is a Solis S6-GR1P5K Model 0205. It has 4 wires connected on the bottom left, which come from a projoy automatic switch which then has 4 more wires going out to the solar panels. I will try to find out the name of the panels and get back.

10-10-20

https://www.boards.ie/discussion/comment/122137502#Comment_122137502

No need for the panel info, it's a dual MPPT. Both MPPT's (strings) should be working.

graememk

If all connected there, Its likely the disconnection is on the roof.

Enterprise1994

There doesn't seem to be any loose connections inside the attic. Its hard to tell from the ground, but one set of panels seem to have much more visible wiring than the rest. It is split into 3 groups on the roof (6 + 4 + 6). We will probably have to wait for a technician unfortunately. The company said no tech people are available to talk at the moment and will call back later, don't have much hope after they failed to call back yesterday. Upon asking to confirm if our second appointment arranged yesterday had been successfully scheduled (after the previous no show) it turns out it had not and we were offered the same appointment date again. Third time lucky! Thanks for everyone's help here.

Buffman

https://www.boards.ie/discussion/comment/122137715#Comment_122137715

Ye, looks to be OK there in the attic from what I can see, the issue is probably further up on the roof. Hopefully (for them) the company have records of which panels they put on which string which should simplify the fault finding a bit. Hope you get sorted soon.

And just to confirm that you're correct that 13 units on a nice sunny day is low, I know someone with a very similarly sized system to yours and 30ish would be more normal on a good day.

Enterprise1994

Thankfully the company was able to change their call out schedule and slot us in this morning. There was a faulty unit on the roof between the one string of solar panels and the inverter.

Everything seems to be working great now with the amount of kW/h produced more than doubling.

Thanks again for everyones help.