Fault Code Reference

SolaX Fault Codes

SolaX hybrid inverters including X1 and X3 series with T-BAT battery storage. Popular across UK installations with G4 generation products and SolaXCloud monitoring.

96

Fault codes

Device types covered

Inverter (96)

Common fault codes

SPI Comms Fault

DC isolator off, wait 30 seconds, restart.

SCI Comms Fault

DC isolator off, wait 30 seconds, restart.

CAN Bus Comms Fault

Full power cycle: AC off, battery off, wait 60s, battery on, AC on.

PV Config. Fault

PV Array Config Error

Check string polarity. Restart.

Internal Memory Failure (IE 26)

Internal Relay Fault

Shut down system immediately.

All SolaX fault codes

SPI Comms Fault

DC isolator off, wait 30 seconds, restart.

SCI Comms Fault

DC isolator off, wait 30 seconds, restart.

CAN Bus Comms Fault

Full power cycle: AC off, battery off, wait 60s, battery on, AC on.

PV Config. Fault

PV Array Config Error

Check string polarity. Restart.

Internal Memory Failure (IE 26)

Internal Relay Fault

Shut down system immediately.

Detection Circuit Fault

Contact SolaX immediately.

RCD Fault (IE 27)

Check DC/AC impedance. Full restart.

Fan 1 Device Fault (IE 112)

Restart. Check for visible blockage (do NOT open unit).

Fan 2 Device Fault (IE 113)

Restart. Check for visible blockage.

AC Current Sensor Fault

DC isolator off, restart.

EPS Mode Overload (IE 16)

Turn off high-power loads. Press ESC on LCD to restart.

EPS Overcurrent

Remove non-linear loads. Restart.

EPS Relay Fault

EPS Relay Fault (IE 29)

TZ Protect Fault

Overcurrent Protection (IE 01)

Wait for auto-recovery. Restart if not.

DCI Device Fault

DC Injection Device Fault

Grid Lost Fault

No Grid Connection (IE 02)

Check main consumer unit breaker. Check if neighbours have power.

Grid Volt Fault

Grid Voltage Out of Range (IE 03)

Set Advanced Setting > Export Control to reduce export or enable voltage respons…

Grid Freq Fault

Grid Frequency Out of Range (IE 04)

Auto-reconnects. Contact DNO if frequent.

Grid Sync Failure

Auto-reconnects.

Internal Bus Voltage Fault (IE 06)

Inverter Overcurrent Protection

Wait for auto-recovery.

PV String Voltage Fault (IE 05)

Check open-circuit voltage of strings vs inverter MPPT range.

Isolation Fault

Insulation Resistance Fault (IE 13)

If morning only and self-clearing: condensation false positive -- update firmwar…

Temp Over Fault

Overtemperature (IE 14)

Check fans running. Check clearances (300mm all sides, 500mm bottom). Check ambi…

Battery CAN Comms Fault

Check LCD Battery Type setting matches installed battery. Re-seat CAN cable. Che…

Charger Overtemperature

Check ventilation. Confirm ambient temperature is within range.

Charger Bus Voltage Over Limit

Wait for auto-recovery.

Charger Below Minimum Temperature

Check ambient temperature. Battery will not charge below minimum -- normal in ve…

Battery Over-Voltage

Wait for auto-recovery.

Charger Overcurrent

Charger Memory Fault

CT / Smart Meter Fault (IE 37)

Check CT is on L wire only, arrow pointing toward grid. Check CT connection at i…

WiFi Module / Monitoring Fault

Check dongle buckle clips aligned correctly. Power cycle inverter. Check WiFi cr…

Real-Time Clock Fault

AC5M Volt Fault

Grid Voltage Out of Range 5 Minutes

Auto-reconnects. Log with SolaXCloud. Contact DNO if frequent.

AC10M Volt Fault

Grid Voltage Out of Range 10 Minutes (IE 08)

Contact DNO with timestamped voltage log from SolaXCloud.

Battery Voltage Fault

Check battery voltage on LCD (System Status, Battery) against the battery spec.

DCI Overcurrent Protection

Wait for auto-recovery.

DCV EPS Overvoltage Protection

Wait for auto-recovery.

Software Overcurrent Fault

Wait for auto-recovery.

RC Overcurrent Protection

Check the impedance of DC input and AC output.

Battery Connection Direction Fault

Isolate the system fully, then verify battery cable polarity at both ends before…

PV Arc Detected (IE 17 X3 / IE 22 X1)

Inspect PV string cabling and MC4 connectors for damage or loose mating.

Battery Power Low

Switch off high-power loads and press ESC to restart.

BMS Lost -- Battery Comms

Check the comms cable is seated at the inverter BAT port and the battery BMS por…

Check for visible debris around the fan (do not open the unit).

Low Temperature Fault

Check ambient temperature at the install location; wait for it to rise.

Other Device Fault (X1)

Update inverter firmware and press ESC to restart.

Internal Comms Fault

Restart the inverter.

Grid Relay Fault

Disconnect PV, battery and grid, then reconnect.

PV Connection Direction Fault

Isolate the system, then verify PV string polarity with a meter before reconnect…

Battery Charge Relay Fault

Press ESC to restart the inverter.

EPS Earth Relay Fault

Press ESC to restart the inverter.

Parallel Fault (X3)

Check parallel comms and earth cable connections between inverters.

Hard Limit Fault (X3)

Check the HardLimit value in Export Control settings against the DNO agreement.

Power Type Fault

Upgrade firmware and press ESC to restart.

EPS Port Overcurrent Warning

Check EPS load against the system rating, then press ESC to restart.

Manager EEPROM Fault

Shut down PV, battery and grid, then reconnect.

Arc Self-Test Fault

Arc Self-Test Fault (IE 104 X1 / IE 115 X3)

Manually clear via the ARC Clear menu and re-run the self-test.

NTC Sample Invalid

Check the NTC is properly connected and in good condition.

Battery Temperature Low

Check the battery installation environment.

Battery Temperature High

Check battery ventilation and heat dissipation around the modules.

Check the meter is compatible with the inverter and powered.

Bypass Relay Fault

Press ESC to restart the inverter.

Arc Hardware Fault (X3)

Record inverter SN and firmware version from the About menu.

BMS External Comms Error

Check the comms cable between inverter and battery.

BMS Internal Comms Error

Power cycle the battery.

BMS Overvoltage

Power cycle the battery and monitor.

BMS Undervoltage

Recharge the battery above the protection level (enable grid charging if needed)…

BMS Charge Overcurrent

Power cycle the battery and monitor charge current.

BMS Discharge Overcurrent

Reduce discharge load, then power cycle the battery.

BMS Temperature High

Check battery ventilation and ambient temperature.

BMS Temperature Low

Check ambient temperature and battery heating settings.

Allow a full balance charge -- charge to 100 percent and hold for several hours.

BMS Hardware Protection

Record battery model, SN and BMS firmware version.

BMS Circuit Fault

Restart the battery.

BMS Insulation Fault

Check the battery is properly earthed, then restart the battery.

BMS Voltage Sensor Fault

Power cycle the battery.

BMS Temperature Sensor Fault

Restart the battery.

BMS Current Sensor Fault

Power cycle the battery.

BMS Relay Fault

Power cycle the battery.

Battery Type Unmatch

Check the battery type setting on the inverter LCD matches the installed battery…

BMS Version Unmatch

Upgrade the battery BMS firmware.

BMS Manufacturer Unmatch

Upgrade the battery BMS firmware and confirm the battery model is supported.

BMS Software Unmatch

Upgrade the battery BMS firmware.

BMS Master/Slave Unmatch

Check module DIP switch addressing (each module needs a unique address).

Charge Request No Response

Upgrade the battery BMS firmware, then power cycle.

BMS Software Protect

Upgrade the battery BMS firmware.

Power cycle the battery.

BMS Self-Check Fault

Power cycle the battery.

BMS Temperature Difference

Check module ventilation and spacing is even across the stack.

BMS Break Fault

Power cycle the battery.

BMS Flash Fault

Record battery model, SN and BMS firmware version.

BMS Precharge Fault

Full power cycle: AC off, battery off, wait 60 seconds, battery on, AC on.

Battery Breaker Open

Check the battery breaker is ON.

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