Solar PV Hints, Tips & Troubleshooting

viewofthehill

https://www.boards.ie/discussion/comment/122643191#Comment_122643191

Just had a look at the data for those days. The reason for the spike is duplicate information being sent by the logger (within 35 seconds of the previous upload) so when graphing the graph is based on minutes and the voltages are summed (doubled).

graememk

https://www.boards.ie/discussion/comment/122644702#Comment_122644702

Ah thats ok then. (voltage spikes)

On a normal day like today is it still happening?

viewofthehill

https://www.boards.ie/discussion/comment/122644891#Comment_122644891

Yesterday never went above 100v for the entire day

Today is showing a similar pattern

graememk

Whats springing to mind other than an inverter fault, is that there is a poor connection somewhere.
(places could be MC4 connections on inverter, The DC isolater, The fireman switch, or the connections on the roof)

On the good days, it can overcome it but today being cloudy, It cant.

Can you see when it started happening?

I have seen this on a DC Isolator that has failed, due to water ingress. If I wiggled it I could get it back at full power.. sometimes. Needed replacing, No external signs but once opened it was destroyed (and stank) (both strings are the same aspect

we think it got into the conduit on the roof, and slowly worked its way in over time, Install was in about 3-4 years at this point. Back in action again with new isolator and precautions taken so not to happen again.

cobham

It is two years since our install. I was looking forward to decent hot water via Eddi today after dull past days but it is misbehaving or the whole system is? no power going to water or anywhere according to the Myenergi app.

Can anyone recommend a 'consultant' to check over the system. I never felt we got properly set up by installer and have no faith to chase him down at this stage.

graememk

https://www.boards.ie/discussion/comment/122648625#Comment_122648625

What does the screen of the eddi show, and the screen of the inverter show?

cobham

Inverter seems to give decent info… nearly 3 from solar and over 2 going to house (wash machine just turned on) . Eddi says 'waiting for surplus'. I did look at it and it needed some update so did that and also turned it off for 10 minutes. I was able to do a 'boost' to manually heat water. Myenergi app is showing no activity and 'waiting for surplus'. Bright sun since dawn so expected decent tank of hot water by now.

GarlicBed

https://www.boards.ie/discussion/comment/122648764#Comment_122648764

What does the screen on the eddi show ? Does it show the export ?

cobham

No activity on Eddi screen and 'waiting for surplus'. Myenergi app now showing 3.7 going to grid.

GarlicBed

Have you a zappi and is it the master device ?
If you do check to see if they are still talking to each other . linked devices on the zappi

cobham

No zappi. All readings on Eddi are 0%…. have installed updates as requested today..

cobham

No zappi

GarlicBed

https://www.boards.ie/discussion/comment/122649147#Comment_122649147

If the app is showing correct then its getting the info from the eddi (Via hard wired CT or Harvi).

I'd try the myenergi forums .

championc

Take a pic of the actual Eddi screen.

viewofthehill

https://www.boards.ie/discussion/comment/122642858#Comment_122642858

I have a call in with Sofar support but am still waiting for a reply.

The same pattern was showing earlier this morning so (in standard IT practice) I turned off the DC isolator switch and then turned it on again and the voltage in both arrays went up to over 300volts. Today is extremely overcast so there is very low light but the voltage still went up to over 300 on both strings. Can anyone think of anything that would be reset in a reboot that may cause this to happen.

10-10-20

https://www.boards.ie/discussion/comment/122653288#Comment_122653288

Hmm - it might be like @graememk suggested and be a bad connection, possibly in that isolator switch. Sometimes you can get a build-up of corrosion on the contacts and they cause resistance and voltage issues… but that's typically associated with localised heating on the isolator. One thing to mention is that it's risky to switch high-current DC like that (even if it's in a faulted state) - the DC isolator is not supposed to be operated before the AC and battery load is first isolated or shut-off.

See does the system stabilise after operating that isolator, and if it comes back then repeat the test (with no load) and then it might give you an indication that it's a faulty isolator… except I have my doubts.

graememk

https://www.boards.ie/discussion/comment/122653324#Comment_122653324

There was no external indication on the isolator I seen. But you knew about it when opened, the smell was awful.

On my one it wouldn't even turn off, just rotated and sprung back into the on position.

It's definitely worth an investigation, and during daylight there's 3-400v in that isolator.. on each string.

viewofthehill

https://www.boards.ie/discussion/comment/122642858#Comment_122642858

Issue with the voltage appears to be resolved. It follows two firmware updates to the inverter by support to resolve. It appears it was going on for a while. Generation for the last few months was down a bit (about 150Kwh a month) but I attributed it to the poor weather. Only when we got the real good days in September and saw the app showing generation of 1Kw on an 8+Kw system did I look more closely at it. Anyway good to have it resolved. It saves a complete restart of the system daily.

10-10-20

https://www.boards.ie/discussion/comment/122693970#Comment_122693970

Alright, so a firmware issue and not a string issue like we thought. Glad it's resolved.

Clo-Clo

Not sure if this is right thread, I currently have a small battery which is wall mounted in attic

Im upgrading with more batteries but short of space, if I put down flooring and then fire proof on top top of flooring could you just mount the battery onto the floor instead of wall in attic?

championc

To be honest, LiFePO4 doesn't really burn if it ever went on fire. The inverter would be more likely if anything

But to answer your question, yes, I think so

SD_DRACULA

https://www.boards.ie/discussion/comment/122705179#Comment_122705179

That's how installers do it as well sometimes.

Just be careful with the weight on the joists I suppose

reggie3434

This is current production, even though I've no washing/dishwsher/oven or anything on (just 2 laptops, alexa and fridge), load is 1.9. it seems to be proportional to the PV production.

Mad_Mike

The fact it seems proportional to the pv output alone makes me think the CT clamp needs to be turned around. Seems to be a common problem with some installs where the CT is turned the wrong way. Definitely shouldn't have that kind of load with just a couple of laptops and fridge anyway

reggie3434

Thanks Mike, can I check what the CT clamp is? Is this reporting incorrectly then?

This is the load now, nothing new turned on

Mad_Mike

A CT clamp is literally just a ring that clamps on a cable to read the current going through that cable and that's where the app gets the info from for solar generation, load being used, exports etc

The fact it seems to change in proportion to the PV generated makes me think it has been just clipped on in the wrong direction and needs to be switched around. Best bet is to contact the installer, although its simple to reverse, but I'd point it out to them that it seems to be measuring the load incorrectly and you think the polarity is wrong

This video just shows what one looks like

https://www.youtube.com/shorts/YqxO81N7eGU

Clo-Clo

https://www.boards.ie/discussion/comment/122707252#Comment_122707252

Yeah I have solid walls so my plan was to place over the solid walls which should provide the support required for the additional weight

Mad_Mike

One of the main reasons I know, is my dad had the same issue on a solar install on a business premises and on the 8th May this year, at 16:30 in the evening the CT was correctly changed around. You can see the day before, then midway through the 8th and then the difference on the 9th!

reggie3434

https://www.boards.ie/discussion/comment/122707784#Comment_122707784

THanks a mill for that Mike, I could of really googled that myself in fairness so thanks again for that.

TBH the Flogas offer/partner has turned out to be a very frustrating experience and I wouldn't recommend it

Mad_Mike

No worries at all, honestly it seems to be a common issue experienced by people and I've seen multiple people report it on the Irish Solar Owners group on Facebook and each and every time it's literally as simple as reversing the clamp. I believe most apps or inverter software actually has an inbuilt setting for CT polarity where it can even be reversed there without having to change the clamp around