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Fault code index · SolaX X-Hybrid all models

SolaX Fault Code Index

Every SolaX X-Hybrid inverter and T-BAT / Triple Power battery fault code — what it means, the most likely cause, and what to do. Find your code in the index below or use the category sections to browse by system area.

X1-Hybrid, X3-Hybrid, X1-Boost & X3-Mega T-BAT & Triple Power battery codes included Sourced from SolaX technical documentation

SolaX Fault Code Index

Every SolaX X-Hybrid inverter and T-BAT / Triple Power battery fault code — what it means, the most likely cause, and what to do. Find your code in the index below or use the category sections to browse by system area.
  • X1-Hybrid, X3-Hybrid, X1-Boost & X3-Mega
  • T-BAT & Triple Power battery codes included
  • Sourced from SolaX technical documentation
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13 Trustpilot reviews
Trustpilot Google

I have a GivEnergy system consisting of two batteries, two inverters and a controlling EMS (Energy Management System) which has not worked since Nov 2025. After six months I discovered Solar Tech Support, reached out to them and Ron phoned me back – how often do you get that service? Could not be more helpful – worked directly with me over the phone, outside what I would call normal working hours. Lucid explanations and we were able to discuss the issues and history using camera and email history. As this was a very rare setup, Ron was able to access an EMS expert in the field to confirm the solution. One sunny day in, I am now only paying for standing charge and a few pence for spikes in grid consumption while battery catches up with house demand.

Ian · May 2026 Trustpilot

When my GivEnergy system had an issue, I was completely left without support and had honestly lost all hope. Thankfully, I searched online and found Ron, which completely turned things around. After sending him a message, he responded incredibly fast and called me to assure me that he would get the problem fixed. I really admire his dedicated, supportive nature and his determination to find a solution. With this kind of outstanding attitude and customer service, he has absolutely secured a future customer in me.

Sree · May 2026 Trustpilot

Ron want out of is way to help, nothing was to much. He was very thorough in what he did Very knowledgeable I would highly recommend Ron and his company He did a fantastic job for me. if you have any problems, he'll do his best to help you out and resolve your problem. I wouldn't hesitate to recommend them

Dennis Brown · May 2026 Trustpilot

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)

Tony Deacon · May 2026 Trustpilot

Contacted Ron with a problem and he sorted it out quickly with no problems at all. Very knowledgeable on anything solar/ batteries. I would recommend him to anyone

Phill · May 2026 Trustpilot

I've spoken to Ron a couple of times with issues with my Givenergy installation. Such a friendly knowledge guy very highly recommended. Thank you very much for resolving my issues

michael fairhurst · May 2026 Trustpilot

Contacted Solar Tech Support in desperation. After explaining the issues I had with my system a diagnosis was made and a solution proposed. Fantastic service, even contacted a manufacturer to arrange replacement parts for me. Great communications, explained all they were doing and what I had to do, clearly and precisly. Followed up to confirm all was ok. Excellent service.

Mr Machin · May 2026 Trustpilot

After GivEnergy went into liquidation, just my luck, my battery started playing up (internal board crashed). Contacted my installer - not interested! Found Solar tech support on a Google search. Sooo glad I found this company! Ron is extremely helpful and has plenty of experience. He soon confirmed what the fault was, and helped me to get my system up and running again. Now moved my GivEnergy account to Solar tech support, and will definitely use again if I have more issues. Unusual to find such a helpful company in these times, no morons reading scripts, just direct contact with the engineer.

Keith Ballard · Apr 2026 Trustpilot

Contacted Solar Tech Support when trying to understand what my Givenergy inverter problem might be and what might be my options. Received good/honest advise which backed up my thoughts.

Hugh Speirs · Apr 2026 Trustpilot

Ron is a super star. Two months ago my GivEnergy battery failed a firmware upgrade leaving it a brick. My installer couldn't/wouldn't fix it. GivEnergy couldn't/wouldn't fix it. Then they went into administration and all hope was lost. A flurry of emails later and Ron had diagnosed the fault (failed USB flash drive, something I'd suspected) and talked me through resolving it. Two months of nothing resolved in about 3 hours. It's great to work with someone who pays attention to the details, knows that they're doing (not just following a script) and gets stuff sorted without a fuss or up-charging.

Christopher · Apr 2026 Trustpilot

I can add to the list of customers who had already 'given up' on GivEnergy due to their appalling customer service, and that was before they went into administration (their Trustpilot reviews don't lie!). So you can imagine my desperation when, having changed my ISP and my Inverter, predictably, proving to be the only device that didn't connect automatically to my new network, I found zero prospect of any customer support with GivEnergy having called in the administrators just five days earlier! The salvation came from Solar Tech Support. My IT advisor stumbled across their web site and some very helpful tips for beleaguered GivEnergy customers, as well as an offer to provide direct assistance. Nothing ventured, I decided to drop them an E-Mail, with very low expectations based on my experience of GivEnergy customer support. Within an hour Ron had responded with some pin point advice, and after a few exchanges of E-Mails he had nailed the problem, enabling the combined efforts of my IT advisor and solar installer to resolve it and reconnect my Inverter. Thank you Solar Tech Support, and Ron in particular, for coming to the aid of a deserted and despondent GivEnergy customer. Expert, razor sharp advice and first class customer service, even though I wasn't officially a customer.

customer · Apr 2026 Trustpilot

This company are a rare gem, I had a very unusual problem following a failed firmware upgrade on my GivEnergy kit. I then found out GivEnergy were in administration and had dismissed all their support staff! None of the usual fixes to try and restore my inverter comms would work, and I looked everywhere, forums, GivEnergy youtube support videos - even AI couldn't figure it out. My installer was talking about huge sums for system replacements, and being vague / evasive about if they'd even install replacement GivEnergy inverter. Enter Solar Tech Support, reassuring and knowledgeable from the very start, I've learnt loads about my solar system though the friendly chat while my engineer worked as he diagnosed the problem and figured out a fix procedure that I've not found anywhere else - amazing . If you need solar system repairs - especially if you like me have been left high and dry by GivEnergy, I cannot recommend this company enough. Give them a call.

Andy Thomas · Apr 2026 Trustpilot

I sent a message on their website regarding a problem I have on my Givenergy system. Although not supplied by Ronald, I thought it was worth an email. Within the hour on a Saturday, he phoned and we discussed the problem. He logged in remotely and gave excellent advice. I'm too far away for his on-site help but he did diagnose the problem and was happy also to chat through my thoughts about an upcoming solar/battery install I'm planning. Great bloke.... if only he was nearer!

Philip · Apr 2026 Trustpilot

I have a GivEnergy system consisting of two batteries, two inverters and a controlling EMS (Energy Management System) which has not worked since Nov 2025. After six months I discovered Solar Tech Support, reached out to them and Ron phoned me back – how often do you get that service? Could not be more helpful – worked directly with me over the phone, outside what I would call normal working hours. Lucid explanations and we were able to discuss the issues and history using camera and email history. As this was a very rare setup, Ron was able to access an EMS expert in the field to confirm the solution. One sunny day in, I am now only paying for standing charge and a few pence for spikes in grid consumption while battery catches up with house demand.

Ian · May 2026 Trustpilot

When my GivEnergy system had an issue, I was completely left without support and had honestly lost all hope. Thankfully, I searched online and found Ron, which completely turned things around. After sending him a message, he responded incredibly fast and called me to assure me that he would get the problem fixed. I really admire his dedicated, supportive nature and his determination to find a solution. With this kind of outstanding attitude and customer service, he has absolutely secured a future customer in me.

Sree · May 2026 Trustpilot

Ron want out of is way to help, nothing was to much. He was very thorough in what he did Very knowledgeable I would highly recommend Ron and his company He did a fantastic job for me. if you have any problems, he'll do his best to help you out and resolve your problem. I wouldn't hesitate to recommend them

Dennis Brown · May 2026 Trustpilot

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)

Tony Deacon · May 2026 Trustpilot

Contacted Ron with a problem and he sorted it out quickly with no problems at all. Very knowledgeable on anything solar/ batteries. I would recommend him to anyone

Phill · May 2026 Trustpilot

I've spoken to Ron a couple of times with issues with my Givenergy installation. Such a friendly knowledge guy very highly recommended. Thank you very much for resolving my issues

michael fairhurst · May 2026 Trustpilot

Contacted Solar Tech Support in desperation. After explaining the issues I had with my system a diagnosis was made and a solution proposed. Fantastic service, even contacted a manufacturer to arrange replacement parts for me. Great communications, explained all they were doing and what I had to do, clearly and precisly. Followed up to confirm all was ok. Excellent service.

Mr Machin · May 2026 Trustpilot

After GivEnergy went into liquidation, just my luck, my battery started playing up (internal board crashed). Contacted my installer - not interested! Found Solar tech support on a Google search. Sooo glad I found this company! Ron is extremely helpful and has plenty of experience. He soon confirmed what the fault was, and helped me to get my system up and running again. Now moved my GivEnergy account to Solar tech support, and will definitely use again if I have more issues. Unusual to find such a helpful company in these times, no morons reading scripts, just direct contact with the engineer.

Keith Ballard · Apr 2026 Trustpilot

Contacted Solar Tech Support when trying to understand what my Givenergy inverter problem might be and what might be my options. Received good/honest advise which backed up my thoughts.

Hugh Speirs · Apr 2026 Trustpilot

Ron is a super star. Two months ago my GivEnergy battery failed a firmware upgrade leaving it a brick. My installer couldn't/wouldn't fix it. GivEnergy couldn't/wouldn't fix it. Then they went into administration and all hope was lost. A flurry of emails later and Ron had diagnosed the fault (failed USB flash drive, something I'd suspected) and talked me through resolving it. Two months of nothing resolved in about 3 hours. It's great to work with someone who pays attention to the details, knows that they're doing (not just following a script) and gets stuff sorted without a fuss or up-charging.

Christopher · Apr 2026 Trustpilot

I can add to the list of customers who had already 'given up' on GivEnergy due to their appalling customer service, and that was before they went into administration (their Trustpilot reviews don't lie!). So you can imagine my desperation when, having changed my ISP and my Inverter, predictably, proving to be the only device that didn't connect automatically to my new network, I found zero prospect of any customer support with GivEnergy having called in the administrators just five days earlier! The salvation came from Solar Tech Support. My IT advisor stumbled across their web site and some very helpful tips for beleaguered GivEnergy customers, as well as an offer to provide direct assistance. Nothing ventured, I decided to drop them an E-Mail, with very low expectations based on my experience of GivEnergy customer support. Within an hour Ron had responded with some pin point advice, and after a few exchanges of E-Mails he had nailed the problem, enabling the combined efforts of my IT advisor and solar installer to resolve it and reconnect my Inverter. Thank you Solar Tech Support, and Ron in particular, for coming to the aid of a deserted and despondent GivEnergy customer. Expert, razor sharp advice and first class customer service, even though I wasn't officially a customer.

customer · Apr 2026 Trustpilot

This company are a rare gem, I had a very unusual problem following a failed firmware upgrade on my GivEnergy kit. I then found out GivEnergy were in administration and had dismissed all their support staff! None of the usual fixes to try and restore my inverter comms would work, and I looked everywhere, forums, GivEnergy youtube support videos - even AI couldn't figure it out. My installer was talking about huge sums for system replacements, and being vague / evasive about if they'd even install replacement GivEnergy inverter. Enter Solar Tech Support, reassuring and knowledgeable from the very start, I've learnt loads about my solar system though the friendly chat while my engineer worked as he diagnosed the problem and figured out a fix procedure that I've not found anywhere else - amazing . If you need solar system repairs - especially if you like me have been left high and dry by GivEnergy, I cannot recommend this company enough. Give them a call.

Andy Thomas · Apr 2026 Trustpilot

I sent a message on their website regarding a problem I have on my Givenergy system. Although not supplied by Ronald, I thought it was worth an email. Within the hour on a Saturday, he phoned and we discussed the problem. He logged in remotely and gave excellent advice. I'm too far away for his on-site help but he did diagnose the problem and was happy also to chat through my thoughts about an upcoming solar/battery install I'm planning. Great bloke.... if only he was nearer!

Philip · Apr 2026 Trustpilot
How to find your fault code. SolaX fault codes appear on the inverter LCD display and in the SolaX Cloud app under the fault or alarm history. Grid and inverter faults use short names (Grid Volt, PLL Lost, Isolation). Battery charger faults are prefixed with C1 (e.g. C1 CAN, C1 TEMP). BMS faults use the BMS_ prefix. Match your code to the categories below.
Grid & AC faults

Fault codes triggered when grid voltage or frequency is outside safe limits, or the grid connection is lost. The inverter disconnects as required by UK grid codes G98/G99 and reconnects automatically when conditions normalise.

Grid Volt / E012 ⚠ Most common
Grid voltage outside the 216V–253V safe range. Almost always overvoltage above 253V during peak solar export. The inverter reconnects automatically when voltage drops. If recurring every sunny afternoon, this is a network issue — report to your DNO and consider export limitation.
Grid Freq Grid frequency error
Grid frequency outside the safe range (47.5Hz–52Hz). Caused by grid instability, not an inverter fault. The inverter reconnects automatically when frequency normalises. Single events after storms or outages are normal. Recurring events suggest a weak grid connection.
Grid Lost / IE02 No grid connection detected
Inverter cannot measure grid voltage at all. Check: AC isolator is on, consumer unit breaker for the solar circuit has not tripped, AC cable connections at the inverter are tight. If mains power is present and all connections are secure, the internal grid relay may be faulty.
PLL Lost Grid sync failure
The inverter lost synchronisation with the grid frequency — it could not maintain a stable phase lock. Often occurs during grid instability after storms or power cuts. Usually clears within minutes. If persistent, check AC wiring and neutral connections.
AC5M Volt Voltage out of range 5 min
Grid voltage has been outside the acceptable range for more than five consecutive minutes. The inverter has shut down to protect itself. More serious than a brief Grid Volt trip — suggests a sustained grid voltage problem. Check SolaX Cloud for the voltage reading and contact your DNO.
AC10M Volt Voltage out of range 10 min
Grid voltage has been outside specification for more than ten minutes. The grid at your property is persistently unstable. This requires DNO investigation — the distribution network may need reinforcement or the transformer tap may need adjusting.
Grid Relay Internal relay fault
Internal grid relay switch malfunction. Can be caused by a poorly connected neutral line or three-phase unbalance on X3-Hybrid systems. Try a full power cycle first. If the fault returns, the relay or inverter may need replacement — contact an engineer.
DC & Insulation faults

Fault codes related to the DC solar input — panel voltage, insulation resistance, and PV array configuration. Isolation faults are safety-critical and should not be restarted without inspection.

PV Volt PV voltage error
DC input voltage from the solar panels is outside the acceptable range — either too high (too many panels in series) or too low (insufficient sunlight, DC isolator off, or a broken string). Check the DC isolator is on and MC4 connections are secure. If voltage is above the inverter's maximum input rating, the string design needs reviewing by an installer.
Isolation ⚠ URGENT — do not restart
Insulation resistance between the DC circuit and earth has dropped below the safe threshold. This is a safety-critical fault — electricity is leaking from the DC wiring. Do not restart the system. Common causes: water ingress at MC4 connectors, damaged cable insulation, or a faulty panel junction box. Contact a qualified engineer for inspection before any restart.
PV Config. PV array configuration error
The PV array configuration in the inverter settings does not match the physical panel connections. This can occur after a panel replacement or if the string configuration was changed without updating the inverter settings. Check MPPT input assignments and PV configuration in the inverter menu.
Internal inverter faults

Fault codes originating from inside the inverter — processor communication, cooling, overcurrent protection, and memory errors. Try a full power cycle first. If the fault returns, the inverter needs professional diagnosis.

SPI SPI communication fault
Internal processor communication error. The inverter's internal components have lost synchronisation. Perform a full power cycle — AC off, DC off, wait 60 seconds, DC on, AC on. If the fault returns, the control board may need firmware reflash or replacement.
SCI SCI communication fault
Internal SCI serial communication has failed. Similar to SPI — an internal processor issue. Power cycle the system. If persistent, the main control board or DSP may need replacement. This is not user-serviceable.
Bus Volt DC bus voltage out of range
The internal DC bus voltage is too high or too low. This is the voltage on the inverter's internal power conversion stage — not the panel input. Often caused by a grid voltage spike or a transient event. Power cycle first. If persistent, the inverter's power stage may be failing.
Inv OCP Overcurrent protection
Inverter has detected current above the safe limit on the AC output. May self-clear after a brief overload event. If persistent, check for a short on the AC output wiring or an internal inverter fault. Do not keep restarting if the fault returns immediately.
Temp Over Overtemperature shutdown
Internal temperature has exceeded the thermal shutdown threshold. Check ventilation clearances (minimum 20cm all sides), ensure no direct sunlight on the inverter, and clear any dust from cooling vents. If the environment is cool and ventilation is adequate, the internal temperature sensor may be faulty.
Fan1 / Fan2 Cooling fan failure
One or both internal cooling fans are not spinning or running at an abnormal speed. The inverter will derate or shut down to prevent overheating. Check for debris blocking the fan intake. If the fan has seized, it needs replacement — this is a common wear item on older X-Hybrid units.
Relay Relay malfunction
Internal relay switch has failed its self-test. The inverter cannot safely connect to the grid. Power cycle first. If the fault returns, the relay has worn out or failed — the inverter needs professional repair or replacement. This is more common on older units with high switching cycles.
RCD Residual current device fault
The inverter's internal RCD has detected a leakage current. This is a safety protection — do not ignore it. It may indicate an earth fault on the AC side. Check AC wiring connections. If persistent, the inverter or the AC wiring needs professional inspection.
Inv. EEPROM Internal memory fault
The inverter's EEPROM memory chip has experienced an error. Settings or calibration data may be corrupted. A firmware reflash may resolve the issue. If the fault persists after a power cycle, the control board likely needs replacement.
Sample Detection circuit failure
The inverter's internal voltage or current detection circuit has failed its self-check. The inverter cannot accurately measure its own output and has shut down as a safety measure. Requires professional diagnosis — the measurement circuits may need recalibration or the control board may be faulty.
TZ Protect Overcurrent protection triggered
The inverter's internal overcurrent protection mechanism has been activated. Similar to Inv OCP but triggered by the hardware protection circuit rather than the software limit. Power cycle first. If persistent, the output stage or power components may be damaged.
DCI Device DC injection device fault
The DC injection monitoring circuit has detected a fault. This safety circuit ensures no DC current enters the AC grid. A power cycle may clear a transient fault. If persistent, the DCI monitoring hardware needs professional inspection.
RTC Real-time clock fault
The inverter's internal clock has malfunctioned. This can cause ForceTime and TOU schedules to run at the wrong time, and SolaX Cloud timestamps to be incorrect. A power cycle and clock resync via SolaX Cloud usually resolves this. If persistent, the RTC battery on the control board may need replacing.
Battery charger faults (C1)

C1-prefixed codes relate to the battery charger circuit inside the X-Hybrid inverter. These affect battery charging and discharging but solar generation to the grid may continue.

C1 CAN ⚠ Common — battery comms lost
Communication between the inverter and battery via CAN bus has failed. The most common cause is a loose CAN cable, wrong battery type selected in inverter settings (T-BAT vs Triple Power), or a missing termination resistor. See our BMS communication fault guide.
C1 TEMP Charger overtemperature
The battery charger circuit inside the inverter is running too hot. Check ventilation clearances and ambient temperature. If the inverter is in a confined space or exposed to direct sunlight, relocating or improving airflow may resolve the issue. The charger will resume when temperature drops.
C1 FAN Charger fan failure
The cooling fan for the battery charger section is not working. Dust or debris may be blocking the fan. If the fan has seized, it needs replacement. Without cooling, the charger will overheat and stop charging the battery.
C1 Bat OVP Battery overvoltage
Battery voltage has exceeded the safe maximum. The charger has stopped to protect the battery cells. This can indicate a BMS fault, a cell imbalance, or incorrect battery settings. Do not keep restarting — the battery needs professional inspection to check cell voltages and BMS health.
C1 Bus OVP Charger bus overvoltage
The internal DC bus voltage in the charger circuit has exceeded the safe range. Often a transient event that clears with a power cycle. If persistent, the charger's power conversion stage may be failing and needs professional diagnosis.
C1 TZ Charger protection triggered
Hardware overcurrent protection in the charger circuit has been activated. The charger has shut down to prevent damage. Power cycle first. If persistent, the charger's power components may be damaged — professional repair is needed.
C1 EEPROM Charger memory fault
The charger section's EEPROM memory has experienced an error. Calibration or configuration data may be corrupted. A firmware update may resolve the issue. If the fault persists after a power cycle, the charger control board needs attention.
C1 Temp Low Charger below min temperature
The charger is too cold to operate safely — the ambient temperature has dropped below the minimum operating threshold. Common in unheated garages or outbuildings during winter. The charger will resume when the temperature rises. Insulating or heating the space may help in cold climates.
C1 HCT1 / HCT2 Charger current sensor fault
The current measurement sensor in the charger circuit has failed its self-check. The charger cannot accurately measure how much current is flowing to or from the battery. Professional repair needed — the sensor or control board may need replacement.
C1 Charger OCP / Boost OCP Charger overcurrent
Overcurrent detected in the charger or boost circuit. Too much current is flowing through the charging path. This can be caused by a battery fault, a short in the DC battery wiring, or a failing power component in the inverter. Power cycle first — if it returns, professional diagnosis is needed.
Battery BMS faults

BMS (Battery Management System) faults relate to the T-BAT or Triple Power battery itself — communication, isolation, relay, and internal errors. See our dedicated BMS fault guide for full diagnosis steps.

BMS_Lost ⚠ Common — battery not detected
The inverter cannot detect the battery at all — the CAN bus communication link is completely down. Check the CAN cable at both ends, verify the battery type setting matches the installed hardware (T-BAT vs Triple Power), and check the 120Ω termination resistor is in place. See our BMS fault guide.
BMS_Internal_Err BMS internal error
Usually caused by a DIP switch misconfiguration on stacked battery modules, or a loose CAN cable at the battery management unit. Check DIP switch positions match the number of modules installed (0 for one, 1 for two, 2 for three). Also check all inter-module RS485 cables on stacked systems.
BMS Relay Fault BMS relay failure
The battery's internal relay has failed. Try resetting the BMU (Battery Management Unit) by power cycling the battery. If the fault persists after restart, the BMU may need replacement. This is not user-serviceable — contact an engineer.
BMS_ISO Fault Battery isolation fault
Insulation resistance within the battery system has dropped below the safe threshold. This is a safety-critical fault — do not restart without professional inspection. Possible causes include water ingress into the battery enclosure, damaged internal wiring, or a failing battery cell.
BMS Circuit Fault BMS internal circuit failure
An internal circuit within the BMS has failed. Try a full battery power cycle — turn off the battery, wait 60 seconds, turn it back on. If the fault returns, the BMS control board needs replacement. This fault typically requires on-site repair.
Monitoring & metering faults

Faults related to the CT clamp, smart meter, EPS (backup) mode, and monitoring connectivity. These typically do not stop solar generation but may affect battery control, export limiting, or monitoring accuracy.

CT CT clamp / smart meter error
The current transformer (CT clamp) or smart meter connected to the inverter is not reading correctly. This affects export limitation accuracy and self-use calculations. Check the CT clamp is clamped around the correct cable, oriented in the right direction, and securely connected to the inverter's meter port. If using a smart meter instead of CT, check the RS485 connection.
AC HCT AC current sensor fault
The inverter's internal AC current sensor has failed. The inverter cannot accurately measure its own AC output. This is an internal hardware fault — the system will shut down as a safety measure. Professional repair or inverter replacement is needed.
Overload (EPS) EPS mode overload
Too much power is being drawn in Emergency Power Supply (backup) mode. The connected loads exceed the inverter's EPS output rating. Reduce the load on the backup circuit — disconnect high-power appliances. If EPS overload occurs during a power cut, the backup circuit may need redesigning to include only essential loads.
EPS Relay EPS relay failure
The relay that switches the inverter into backup mode has failed. The system will not provide backup power during a grid outage. Solar generation and grid-connected operation may still work normally. The EPS relay needs professional replacement.
EPS OCP EPS overcurrent
Overcurrent detected in the EPS output — more current is being drawn than the inverter can safely supply in backup mode. This is similar to Overload but triggered by the hardware protection. Reduce the load on the backup circuit immediately.
DM9000 Network DSP fault
The network digital signal processor — responsible for the Pocket WiFi dongle communication — has malfunctioned. SolaX Cloud monitoring may go offline but the inverter and battery continue operating normally. A power cycle usually clears this. If persistent, the communication module may need replacing.
Frequently asked questions
How do I find fault codes on my SolaX inverter?
Fault codes appear on the inverter LCD display and in the SolaX Cloud app under fault or alarm history. Grid and inverter faults use short names (Grid Volt, PLL Lost, Isolation). Battery charger faults are prefixed with C1 (e.g. C1 CAN, C1 TEMP). BMS faults use the BMS_ prefix. Match your code to the categories in this index.
What do SolaX fault codes starting with C1 mean?
C1 codes relate to the battery charger circuit inside the X-Hybrid inverter. C1 CAN means communication with the battery has failed. C1 TEMP means the charger is overheating. C1 Bat OVP means battery voltage is too high. Most C1 codes need a power cycle first — if the fault returns, professional diagnosis is needed.
Can I restart my SolaX to clear a fault code?
Grid faults (Grid Volt, Grid Freq) clear automatically when grid conditions normalise. For internal faults, a power cycle can clear transient errors — AC off, DC off, wait 60 seconds, DC on, AC on. If the same fault returns after restart, the issue is persistent and needs diagnosis. Isolation faults and BMS_ISO faults should not be restarted without professional inspection.
Why does my SolaX show Grid Volt every sunny afternoon?
A recurring Grid Volt fault during sunny afternoons means mains voltage at your property is exceeding 253V when multiple local solar systems are exporting simultaneously. The inverter disconnects because UK grid code requires it — this is correct behaviour, not a defect. Report the issue to your DNO with voltage readings from SolaX Cloud. Consider configuring export limitation on your inverter to reduce your contribution to the voltage rise.

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