Inverter replacement (?) - Newcastle

kaysdee

Can anyone please offer me any guidance with who I should contact to check my current set up?

We had our solar array installed in 2011, so receiving the fit generation payment, and it is still using the original Sunny Boy inverter. The installer has long since gone bust. Everything has been working fine until recently when I realised the reading at the PV meter is the same as the last time I read it.

The inverter is in the loft so I checked it out and it still has power when you tap the screen, there are no warning lights or error messages but the bar graph where you’d normally see the generation is flat and it’s showing 0 generated today (every day), obviously confirmed by no movement on the PV meter (not sure how long).

I switched off the DC and AC switches, left it a while and switched them back on. The inverter reboots, but still no generation, so I need to get this looked at, but not sure who to turn to.

I just got an electric car and I’m awaiting the charger installation. As I now have an ev, I started looking at batteries and have a quote from Octopus (they’re doing the charger) for a battery and got my hopes up that since that comes with an inverter, I could kill two birds with one stone, but I obviously misunderstood how it all works and now realise that wouldn’t do anything for the solar generation.

My husband used to take care of all this, but is sadly now in a care home with young onset dementia, so I don’t want to make any mistakes (costly ones at that!) Can anyone give me any guidance as to who I should contact or local installers? If I need to replace the inverter, I’d probably get the battery from them too as I’m assuming that would reduce the cost.

To complicate matters, I’ve been in a dispute with British Gas as I haven’t had any generation payments in over a year. I think we’re nearing the end of the complaint and received my email today advising I can now go to the ombudsman. Something happened last February, very coincidentally around the time they said we needed to state whether we wanted to stay on 50% deemed export or move to measured export from the smart meter. I chose to stay on the deemed 50% but over the (many!) months of emails and communications to resolve matters, I think they messed something up and it suspended the payments. It has taken forever for them to explain what the issue is with long periods of before I get the next email. I’m incredibly frustrated with that already and now this has happened.

Anyway, that was just for an extra bit of context. I’ve probably missed crucial info needed, so happy to answer any questions on the set up, but mainly for local contacts and roughly how much I should expect to pay.

Many thanks in advance

QrizB

Can anyone give me any guidance as to who I should contact or local installers? If I need to replace the inverter, I’d probably get the battery from them too as I’m assuming that would reduce the cost.

I'm a long way from Newcastle so can't offer any personal recommendations. It's possible that one or more of the forum regulars from the northeast will be able to suggest an installer.

In the absence of any recommendations, I'd agree that looking for a local installer is probably a good place to start.

If you put your postcode into the MCS database it will give you a list of local MCS-accredited installers.

https://mcscertified.com/find-an-installer/

You can then phone or email around and see which of them are interested in quoting for your inverter replacement.

When I do this with my address, a lot of the firms that appear are general-purpose electrical contractors. For a simple job like an inverter replacement they might be a better chioce than a "solar specialist".

Heedtheadvice

and to add, regarding the tech side of the problem.....

It is quite possible that the fault may be with the solar panels end of things rather than the inverter.

You obviously have not described your solar system but many systems comprise a string of panels ( or two strings) connected together in a long loop by cables and connectors. It only needs 1 panel, cable or connector to fail and the whole PV generation stops. Something such as corrosion in a connector or it coming loose is sometimes all that creates a problem.

Your inverter will no doubt be able to show a reading of the voltage being generated by the panels ( probably a couple of hundred volts for several panals in sunshine)

It should not be beyond virtualy all good electricians to determine if it is a panel generation or inverter issue. If it is a connector cause that is a cheap repair.

I might be useful if you could post more details, Inverter brand and model, panel brand, power and number. This will help to give more advice and it could well be you do not need a new inverter and get you up and running saving money earning FIT again soon.

kaysdee

Thank you. That is a helpful starting point.

The inverter is a Sunny Boy SMA - Model SB 3000HF-30.

I have 18 panels on opposite aspects of the roof, I think NE (8 panels) / SW (10 panels) configuration on separate loops. I have 2 DC isolators and 2 AC isolators and can see cabling coming into inverter from each set/roof direction as the cables come into the loft. I don’t know how panels in each group connect together though.

From a troubleshooting point of view, the fact I have different isolators suggests they are indeed separate loops, so I’d be very unlucky to have developed a fault on both. If one set failed, I assume (possibly incorrectly) the other would still generate, so it’s probably the inverter? So sorry, I only have a basic understanding of the science.

I managed to find an old email which says the panels are 200w A-SUN 200-MB monocrystalline modules and the overall system is 3.6 KW.

I’ve seen the top left number change between 0.05 and 1.0 but nothing changes on the right.

I know the PV reading at the meter downstairs moved between November and March and l only discovered the issue when I saw the current reading is the same as March. It could have stopped any time up to March though, so not quite sure when the issue started.

Thank you

QrizB

Comparing your display to the one in this pdf:

https://files.sma.de/downloads/SB20-30HF-BA-BEN113530.pdf

It looks as though yours has a "gap" where the indicator for the switch should be. Has something been turned off unexpectedly?

Have you checked your fuse box / consumer unit?

Edit to add:

This manual refers to that switch as the "grid relay":

https://www.europe-solarstore.com/download/sma/sunnyboy/SB20HF-30HF-IA-en-32.pdf

Ectophile

With 18 panels and two isolators, it's probably two strings of panels. If you can see the DC wires going in, then I would expect to see two pairs (4 wires). It is unlikely that both strings will have failed.

I agree with @QrizB that it may be that you've lost the AC connection to the inverter. Check all isolators and circuit breakers in case something has tripped. It's not unknown for an RCD to trip after a storm.

Ectophile

On the car charging, I have now signed up for an EV tariff and don't bother trying to charge from solar any more. I program the car to charge overnight instead. Unless you buy a huge battery, it won't be enough to charge the car.

kaysdee

Thanks again.

I can indeed see two pairs (4 wires). The main fuse box is fine, nothing has tripped, and I’ve “powered down” a couple of times, left it an hour and powered back on in reverse.

I have a company coming out on Friday to give me a quote on a battery and EV charger. They said they’d look at the inverter for me free of charge. I have paid Octopus for a charger but we’re 4 weeks down the line and no install date yet.

I haven’t switched tariffs yet as I was waiting for all the above to be sorted. My mileage is currently low, so the higher day rate and standing charge I’d have to move to wouldn’t offset the cheaper overnight rate, at least while I’m not generating. I will be changing when everything is up and running.

Heedtheadvice

That's good of your company. Hope they find the problem.

It'll be well worth a coffee and lots of cake !