Grid overvoltage is the most common cause of repeated SolaX disconnections in the UK. We review your SolaX Cloud voltage data, identify the pattern, and recommend the right fix — export limitation, DNO report, or reactive power adjustment.
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Ron took me through a diagnostic to confirm my GivEnergy Inverter had a fault. A common one as it turns out with the AC Inverter. As GivEnergy is defunct there is no immediate fix, aside from sourcing 2nd hand replacement. It may be that a fix becomes available over the summer which would make a lot of GivEnergy customers happy (Again)
After 6 months of trying to find someone to help with non functioning Givenergy batteries and inverter, I contacted Ron at STS who remotely sorted the problem within days. Highly recommended.
Ron diagnosed the problem remotely - efficiently and order the part identified as the fault - this part came directly from to me and Ron visited within a few days and within the hour corrected the problem and since everything has been excellent -highly recommended - very pleasant manner and lovely to work with . Ivor Morris.
Genius when it comes to solar and off grid installations we spent days trying to work out what was causing our problems and Ron resolved it in less than an hour! Cant reccomend enough
Roland is a true gentleman. He provided a refurbished inverter when my givenergy one failed. The install was a pain and took him hours. I was expecting a big bill but he honoured his price despite the extra effort. While here he diagnosed a battery fault. He helped me get the battery down and recommended an excellent company who could repair the battery. Absolute legend of a person and company
Ron is truly a gem. Logged into my GivEnergy system remotely, dignosed a faulty cell in the battery, providing clear explanation, including screen grabs. Offered advice of companies I could use to fix battery. All completed over WhatsApp with clear, precise & friendly comms. Stayed true to company statement/ethos "We dont fix it, you dont pay" and didn't charge me aynthing. 100% recommend if you have any issues with your solar system.
Work through these steps to understand why your SolaX inverter is disconnecting from the grid, whether it is a network issue or a configuration problem, and what to do about it.
Log into SolaX Cloud and check the fault history. The specific code tells you what the inverter detected:
If the voltage had been running above 253V, the network's limit, in the minutes before the disconnection, or stayed above 262.2V for 1 second, the inverter disconnected because its UK grid protection settings require it — the system is working correctly.
The pattern tells you the root cause. Check the SolaX Cloud event log covering at least the last 30 days:
Export the event log with timestamps — this data is exactly what a diagnostic engineer or your DNO needs to identify the root cause.
SolaX X-Hybrid inverters comply with G98 and G99 UK grid codes. They are required to disconnect when grid voltage stays above 262.2V for 1 second or 273.7V for 0.5 seconds, or when frequency moves outside the safe range; 253V is the network's own limit, which the inverter checks as a 10-minute average. This is a safety mechanism protecting the equipment and the network.
On UK distribution networks where multiple solar systems are connected to the same transformer, simultaneous export during peak generation pushes the local voltage upward. The houses furthest from the transformer see the highest voltage and are the first to trip. This is a network capacity issue — the solution is either export limitation on the inverter side or infrastructure reinforcement by the DNO.
If your SolaX system is rated above 3.68kW, it was installed under the G99 connection standard and may require export limitation. Export limitation restricts how much power the inverter sends to the grid, reducing your contribution to local overvoltage.
On the inverter, navigate to Settings → Advanced Settings → Export Control. If export control is not enabled and your DNO approval letter specifies an export limit, this must be configured. The inverter also needs a CT clamp or meter installed to measure export accurately.
Without correct export control, a G99 system may be non-compliant — the DNO can require disconnection, and you may lose Smart Export Guarantee payments.
If SolaX Cloud shows grid voltage regularly exceeding 250V during generation hours, contact your Distribution Network Operator. The DNO is responsible for maintaining voltage within the statutory range. They can adjust the transformer tap setting to lower voltage across the local network, or reinforce the infrastructure if needed.
Find your DNO by entering your postcode on the Energy Networks Association website. When reporting, provide the voltage readings and timestamps from SolaX Cloud. If your neighbours also have solar systems that are tripping, a joint complaint carries more weight with the DNO.
If grid disconnections continue despite correct export limitation, the inverter's reactive power settings or grid protection parameters may need adjusting within the G99-permitted range. These are installer-level settings that require technical knowledge to configure correctly.
STS can review your SolaX Cloud voltage data remotely, identify whether the issue is a network problem requiring DNO involvement or a configuration issue that can be resolved at the inverter, and recommend the appropriate fix. Remote diagnostic sessions are free — you only pay £125 if we fix it remotely.
Grid disconnection faults are becoming more frequent across the UK as solar installation density increases. The distribution networks in most residential areas were designed for one-way power delivery — from the transformer to the house. When multiple solar systems on the same network begin exporting simultaneously, power flows in the opposite direction and the voltage at the far end of the network rises. Once its 10-minute average goes above 253V, or it stays above 262.2V for 1 second, every inverter on that section is required to disconnect.
Rural and suburban networks are the most affected. These networks tend to have higher impedance — longer cable runs from the transformer — which means voltage rises more for the same amount of export. A street with five or six solar systems can push the local voltage above the trip threshold on a clear summer afternoon, even if each system is relatively small. The houses furthest from the transformer will trip first and most frequently.
SolaX systems installed under G99 (above 3.68kW) should have export limitation configured to reduce their contribution to voltage rise. But many G99 systems were installed without export control enabled, or the CT clamp was never fitted, or the limit was set incorrectly. Correcting the export control configuration often reduces or eliminates the disconnection events without any network reinforcement needed. For systems where export limitation alone is not enough, the DNO needs to adjust the transformer tap or reinforce the local network.
Grid voltage passed the inverter's protection settings. Most commonly overvoltage during peak solar export, when the network goes above its 253V limit. Inverter reconnects automatically when voltage drops.
Inverter lost synchronisation with grid frequency. Often occurs during grid instability after storms, outages, or rapid voltage fluctuations. Usually clears within minutes.
Inverter cannot measure grid voltage at all. Check AC isolators, consumer unit breakers, and wiring connections. If the mains supply is present, the AC cable or a relay inside the inverter may be faulty.
Internal relay switch malfunction. Can be caused by a poorly connected neutral line or three-phase imbalance on X3-Hybrid systems. May require inverter inspection or replacement.
We review your SolaX Cloud voltage data and fault history to determine whether the issue is a network problem requiring DNO action, a missing export limit, or a configuration fix we can resolve remotely.
Due to unprecedented demand we’re currently only carrying out on-site work in Yorkshire, and replies are taking up to 7 days. Remote diagnostics continue for the whole UK as normal.
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