If your system keeps dropping out with an over-voltage fault, the supply is probably out of tolerance — and your inverter has likely been logging the proof. We can pull it and build the case for the network operator.
Ask about an over-voltage checkFoxESS support hubSTS were incredibly responsive and helpful In diagnosing an issue with my GivEnergy inverter. Although distance meant it was impractical for me to use them to fully solve the issue, I’m grateful for the help and detail they provided. Don is a real professional gent and a hero in my eyes.
Solar Tech Support is an absolute lifesaver. My solar and battery system stopped working completely, but after one quick phone call, they fixed the problem straight away. The original provider, GivEnergy, has gone into administration, leaving me entirely without support from the original installers. It was a terrible situation on GivEnergy’s part, but thankfully, Solar Tech Support came to the rescue!
After 7 months of not being able to access/control my system following a change of wi-fi provider, followed by the news that GivEnergy had ceased trading i was left high and dry. I was unable to get any help whatsoever from my installer, tried various electrical tradespeople etc but no-one knew how to help me. Changed the Dongle but then couldnt get this change recognised in the inverter. Found Solar Tech Support while researching yet again online. Ronald has been amazing. Responding very quickly to my emails and very knowledgeable on the system. Managed to give us the information we needed to get the Dongle up and running and created me another account which now works as it should. His help has been invaluable. Thank you so much. Reviews I saw from other people said Solar Tech Support are very good, but i would say they are Outstanding!! Thanks again for all your help- Mick & Sandra
Our SolarEdge PV system with LG batteries had its first hiccup after 8 years of hard work. The Inverter failed. Fortunately I found Solar-Tech-Support who diagnosed the problem very quickly, ordered a replacement unit and fitted it shortly after we received the unit from SolarEdge. Very thorough and professional approach. Thank you, a solid 5 star recommendation.
Ron was brilliant. He really tried to help. He spent hours trying to fix our GivEnergy AIO and ultimately it became apparent that it needed parts to fix the BMS management system. As there appears to be no replacement parts available on the market, he gave excellent advice on what options are now available to move forward. He is incredibly helpful and knowledgeable.
Massively massively recommended. We had a big battery array (49kW across three phases) put in four years ago. c £35k cost. It’s been a total nightmare for many reasons, not least 1. our installer being totally useless and unresponsive and 2. Givenergy, our battery supplier, going bust. Long story short it had never worked anywhere near properly despite countless hours on phones and emails; the best we’d achieved was one third of the batteries working. Rather than write it off, I asked a PM friend to try to source someone who could come on site and review and revive the system. He found Solar Tech Support and Ron. Ron assured us he was the man to get it going again. After so many years of pain, I was not convinced but, true to his word, five hours later it was up and running. Lovely chap, super knowledgeable with a support team to lean on who are also clearly super technical. I honestly didn’t think there was much chance of getting this array going ever again so was absolutely delighted when Ron and team pulled it off. Bravo!
Kerry got in touch because his solar inverter kept shutting itself down — several times a day, every day. He was already fairly sure the cause was high mains voltage. What worried him was the next bit: how do you actually prove that to a network operator, and get them to do something about it? As it turned out, the proof had been sitting inside his own inverter the whole time.
Kerry's FoxESS hybrid kept throwing the same fault — "Code 28 — 10 Minute Average Grid Voltage Fault" — and disconnecting from the grid. To him it looked like the system kept breaking. In fact it was protecting itself. He suspected the grid voltage was simply too high — a common problem as more solar goes onto a network, and especially for homes near the end of a long supply cable — but he had no voltage logger, no obvious way to evidence it, and a very reasonable fear that a phone call saying "I think my voltage is high" would go precisely nowhere.
A network operator is not going to re-tap a transformer or reinforce a street on a hunch. They want evidence: the voltage, measured, over time, breaching the limit. Most homeowners don't own a power-quality logger — and by the time anyone comes out to check, the voltage may happen to look fine. That catch-22 is exactly why people give up.
But there is a piece most people miss. A modern grid-connected inverter is continuously measuring the grid voltage at its own terminals, and logging it. The evidence isn't something you need to go and capture — it has already been recorded, for months, by the very device that keeps tripping.
We exported the inverter's grid-voltage history and its fault log from the FoxESS cloud and analysed them. Across a 19-day window the supply voltage:
And here is the part that settles the argument. A large share of the breaches happened overnight — between roughly 2 am and 5 am — when Kerry's solar was generating nothing at all. That single fact dismantles the usual deflection that "it's your own solar pushing the voltage up." At three in the morning there is no solar export, so a reading above 253 V can only be the network's own voltage. During the day, his solar then stacks on top of an already-high base and pushes it further over the limit.
The inverter's fault log recorded 89 over-voltage disconnections in 15 days — about six a day, and as many as fourteen on the worst day.
Every one of those is the inverter doing exactly what the grid-connection rules (Engineering Recommendations G98 / G99) require: disconnecting when the 10-minute average voltage exceeds 253 V. The inverter wasn't faulty — it was the canary, faithfully logging a supply that was out of tolerance.
The voltage a domestic supply must be kept within is set by the Electricity Safety, Quality and Continuity Regulations 2002. A 230 V supply is permitted to vary by +10% / −6% — a band of 216.2 V to 253 V — and the network operator carries a legal duty to keep it there. A supply repeatedly reaching 255.9 V is outside that band, full stop. Once a customer reports it, the DNO must respond within five working days, or offer to investigate within seven, under the Guaranteed Standards of Performance — with a penalty payment due to the customer if it does not.
We pulled all of it together into a formal report on letterhead: the voltage logs, the fault log, a day-by-day breakdown, the relevant regulations, and a plain explanation of why the inverter is behaving correctly while the supply is not. Crucially, every figure is sourced from the inverter's own records — not opinion. That is the difference between "I think my voltage is high" and a documented breach the network operator has a statutory duty to act on.
The point, for Kerry, is that he didn't need to buy equipment or win a technical argument. The evidence already existed. It simply needed extracting, analysing against the right limit, and presenting in a form the DNO cannot reasonably dismiss.
You're probably not imagining it, and you're almost certainly not at fault. A grid-tied inverter that repeatedly drops out on over-voltage is usually telling you the truth about your supply — and the proof is likely already sitting in your monitoring. We can pull it, analyse it against the statutory limit, and build the evidence pack that gets the network operator to take action.
Tell me what your inverter is doing — the fault it shows and how often. If the supply is out of tolerance, the evidence is probably already in your monitoring, and we can build the case for the network operator.
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