AliG Posted March 1, 2021 Share Posted March 1, 2021 (edited) In my last houe we had solar panels installed under the old high FIT rate. After around 18 months the generation meter broke. I didn't notice for 6 months as I was not regularly checking it. So I lost around £600 of FIT payments and had to pay a couple of hundred for a new generation meter to be installed. It was also a hassle requiring considerable paperwork to get the FIT transferred over when I moved. It took months after we moved. A few months ago we had a massive lightning storm in Edinburgh. Apparently PV systems are not normally protected from lightning. 2 of our 3 inverters broke. Luckily the manufacturer agreed to replace them under warranty. So again after £300 of bills to figure out what was wrong with the system and replace the inverters we were back up and running. That's probably about the value of one year's electricity savings as we aren't on a FIT now. We also cannot get paid for export electricity as we are on three phase and it is still almost impossible to get a three phase smart meter. I did ask the electricians if they regularly have to fix systems and they said yes and that the generation meter was the thing most likely to break. Anyway over Christmas it seemed like we were generating very little PV. I thought it was just the weather, but now it is sunnier I checked it out today. One of the three inverters seems to be broken. it trips the RCD or sends the AC voltage up over 350V when it is on. The other two are not able to generate much electricity as the local grid voltage, which has always been high, keeps drifting over 253V, the point at which they stop exporting and reset. I have two of them running again current voltage is around 245V. I will see what happens at lunchtime tomorrow when everybody is generating. I suspect they will trip out again as the voltage rises with more PV hitting the network. If so I will have to contact the DNO re reducing the voltage. The result of this is I cancelled any plans to put PV on my parents' house as it simply isn't worth the hassle especially when they don't have room for as many panels. I thought it would be pretty much a fit and forget system! Edited March 1, 2021 by AliG Link to comment Share on other sites More sharing options...
SteamyTea Posted March 1, 2021 Share Posted March 1, 2021 You can ask the DNO to reduce the local voltage at the transformer, then you can export OK. The generation meter problem us interesting, they are just normal meters on single phase. Not sure if they have to be different on 3 phase. Maybe @ProDave knows the answer to that. if your parents are on a normal part of the grid, then they should be OK. What inverters you have as they need to be configured for the UK grid, some cannot be changed by a user after they are installed, they need an installer code. Link to comment Share on other sites More sharing options...
AliG Posted March 1, 2021 Author Share Posted March 1, 2021 (edited) 5 minutes ago, SteamyTea said: What inverters you have as they need to be configured for the UK grid, some cannot be changed by a user after they are installed, they need an installer code. Thanks, already checked that. They are configured for the UK, which is a maximum 253V. It seems like over high voltage is not an unusual problem so I will give it a couple of days to check then speak to the DNO. They are Solis inverters, no idea why one seems to be broken again, will wait to get an idea of the voltage issue before pursuing this. My parents will be at the other end of the street. As well as my issues they have a flat roof, so whilst I saved money on tiles the architect wanted to specify a specific flat roof system for PV. This increased the cost of the roof making what I think would be a 3kW system uneconomical. I also couldn't get away from a niggling feeling that drilling holes through your flat roof to mount PV is a recipe for leaks at some point in the future. The electrician felt that generation meters might be lower quality. Edited March 1, 2021 by AliG Link to comment Share on other sites More sharing options...
ProDave Posted March 1, 2021 Share Posted March 1, 2021 Generation meters about £20 on ebay. Any electrician should be able to change it. Or do we have the stupid situation that for a FIT system it must be done by an MCS company? (with the MCS premium)? A generation meter is just the same as a normal electricity meter, I have never know one fail, I did not have them down as being unreliable. Inverters on the other hand, mine packed up 2 weeks ago, I just bought a second hand Sunny Boy on ebay. Link to comment Share on other sites More sharing options...
AliG Posted March 1, 2021 Author Share Posted March 1, 2021 (edited) 3 minutes ago, ProDave said: Generation meters about £20 on ebay. Any electrician should be able to change it. Or do we have the stupid situation that for a FIT system it must be done by an MCS company? (with the MCS premium)? It was replaced by the original MCS installer who are based about an hour away. They appeared to charge me for the time required to come to my house then drive somewhere to get the meter then drive back. So a 15 minute job had hours of labour. I was not pleased. I am thinking I might try switching the cables over to see if it is definitely the inverter, but I suspect it is. Edited March 1, 2021 by AliG Link to comment Share on other sites More sharing options...
SteamyTea Posted March 1, 2021 Share Posted March 1, 2021 I can't remember now, as it was a decade ago. Do generation meters get a MPAN number, and do meter swaps need to be notified to OFGEM. It was a serious offence to misreport the initial meter readings when first installing a system. Easy enough to do a like for like meter or inverter swap as you can isolate the system easily. Just take lots of pictures of where the wires go. Link to comment Share on other sites More sharing options...
AliG Posted March 1, 2021 Author Share Posted March 1, 2021 (edited) 4 minutes ago, SteamyTea said: Do generation meters get a MPAN number, and do meter swaps need to be notified to OFGEM. I had to do all that at my last place. As it was a like for like swap on the inverters they literally had to just take them down and plug the same connectors back in. As I have been up to the loft about 20 times today trying to isolate the problem I am confident I can swap it out myself if required now. As I have two the same and one seems broken I am going to swap the panels and AC connections over just to check it isn't something else. Edited March 1, 2021 by AliG Link to comment Share on other sites More sharing options...
SteamyTea Posted March 1, 2021 Share Posted March 1, 2021 3 minutes ago, AliG said: had to do all that at my last place. Check with MCS, they should know the answer. Regarding your initial question. Yes, you are unlucky. Put up a lightening rod. Link to comment Share on other sites More sharing options...
ProDave Posted March 1, 2021 Share Posted March 1, 2021 34 minutes ago, AliG said: As it was a like for like swap on the inverters they literally had to just take them down and plug the same connectors back in. As I have been up to the loft about 20 times today trying to isolate the problem I am confident I can swap it out myself if required now. So what exactly is your current issue? Link to comment Share on other sites More sharing options...
AliG Posted March 1, 2021 Author Share Posted March 1, 2021 11 minutes ago, ProDave said: So what exactly is your current issue? Two current issues - 1. It looks like the local AC voltage rises above 253V in the middle of the day causing inverters to cut out. If this is the case I can ask the DNO to adjust voltage. 2. We had two inverters replaced. It appears that one of the replacement inverters is no working. Link to comment Share on other sites More sharing options...
ProDave Posted March 1, 2021 Share Posted March 1, 2021 Voltage issue. You need a voltage measurement at your consumer unit, as near the incoming supply as possible, to determine if it is a DNO issue or if it is a problem with the internal wiring, Inverter issue seems to be a supplier / warranty issue. Solis seem to be reliable, the "new Sunny Boy" as far as I can tell. Link to comment Share on other sites More sharing options...
TonyT Posted March 1, 2021 Share Posted March 1, 2021 I think a SPD would be a good investment ( surge protection device) they can be fitted at the consumer unit to protect all the appliances/electronics in the house Link to comment Share on other sites More sharing options...
ProDave Posted March 1, 2021 Share Posted March 1, 2021 3 minutes ago, TonyT said: I think a SPD would be a good investment ( surge protection device) they can be fitted at the consumer unit to protect all the appliances/electronics in the house Won't help much if the lightening strikes the panels. Link to comment Share on other sites More sharing options...
TonyT Posted March 1, 2021 Share Posted March 1, 2021 (edited) Never know, lightning can travel along to the inverter, that’s connected to the mains. Saving other electronics minimising damage Edited March 1, 2021 by TonyT Link to comment Share on other sites More sharing options...
SteamyTea Posted March 1, 2021 Share Posted March 1, 2021 11 minutes ago, ProDave said: Won't help much if the lightening strikes the panels. Seem to remember that the whole DC side is not earthed. If that is still the case, there is only one place it had go though, the inverter and then the meter. Link to comment Share on other sites More sharing options...
ProDave Posted March 1, 2021 Share Posted March 1, 2021 1 minute ago, SteamyTea said: Seem to remember that the whole DC side is not earthed. If that is still the case, there is only one place it had go though, the inverter and then the meter. Correct and with most transformerless inverters they must not be earthed. Link to comment Share on other sites More sharing options...
Stones Posted March 1, 2021 Share Posted March 1, 2021 1 hour ago, ProDave said: Generation meters about £20 on ebay. Any electrician should be able to change it. Or do we have the stupid situation that for a FIT system it must be done by an MCS company? (with the MCS premium)? A generation meter is just the same as a normal electricity meter, I have never know one fail, I did not have them down as being unreliable. Inverters on the other hand, mine packed up 2 weeks ago, I just bought a second hand Sunny Boy on ebay. Do you have to inform SSE of the change in inverter? Link to comment Share on other sites More sharing options...
AliG Posted March 1, 2021 Author Share Posted March 1, 2021 I wouldn't think so. Unless you were increasing the size to be able to export more than 4kW Link to comment Share on other sites More sharing options...
TonyT Posted March 1, 2021 Share Posted March 1, 2021 https://www.dehn-international.com/sites/default/files/media/files/pv-rooftop-wp018-e.pdf you would have to inform the fit provider of a change to the existing system Link to comment Share on other sites More sharing options...
ProDave Posted March 1, 2021 Share Posted March 1, 2021 14 minutes ago, Stones said: Do you have to inform SSE of the change in inverter? I did not, The new one is still compliant with G83 now G98 so I did not want to trouble anyone with unecessary paperwork. This is a non FIT system. Link to comment Share on other sites More sharing options...
SteamyTea Posted March 1, 2021 Share Posted March 1, 2021 15 minutes ago, Stones said: Do you have to inform SSE of the change in inverter? If it is the same model of inverter, you probably don't have to inform them. If different, then yes, they will only need the relevant certificate that comes with it (I can never remember what it is called). They have this for safety reasons, so best to inform them. Link to comment Share on other sites More sharing options...
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