Fault Code Reference

SolarEdge Fault Codes

SolarEdge inverters with DC power optimisers. Widely deployed across UK residential solar with monitoring via the mySolarEdge platform and SetApp commissioning.

49

Fault codes

Device types covered

Inverter (49)

Common fault codes

DC Overvoltage Error

Turn OFF inverter ON/OFF switch. After 5 minutes verify LCD shows low safety vol…

Vref Voltage Error

Verify proper inverter clearances (top, bottom, sides)

Over Temperature

Verify clearances: min 200mm top, 150mm left/right, 100mm bottom

Note exact error code and current software version

Broken or Unconnected Temperature Sensor

Inspect temperature sensor connector (usually near heat sink)

18x / F-Isolation

DC Isolation Fault (Ground Leakage)

Check all DC cables for visible damage, pinch points, or rodent damage. Inspect …

All SolarEdge fault codes

DC Overvoltage Error

Turn OFF inverter ON/OFF switch. After 5 minutes verify LCD shows low safety vol…

Vref Voltage Error

Verify proper inverter clearances (top, bottom, sides)

Over Temperature

Verify clearances: min 200mm top, 150mm left/right, 100mm bottom

Note exact error code and current software version

Broken or Unconnected Temperature Sensor

Inspect temperature sensor connector (usually near heat sink)

18x / F-Isolation

DC Isolation Fault (Ground Leakage)

Check all DC cables for visible damage, pinch points, or rodent damage. Inspect …

1x / Night Mode

Night Mode / Standby (Insufficient Irradiance)

If dark or overcast: wait — inverter will restart automatically when irradiance …

PV Solar Array Isolation Fault

Check PV installation for isolation problems and ground leakage

Internal Communication Fault

Verify all optimizer connectors are securely seated

Note exact error code and timing of occurrence

Line to Neutral Voltage Above Threshold

Check grid connection — all AC breakers properly connected

Line to Neutral Voltage Below Threshold

Check grid connection with multimeter (verify 230V present)

Inverter Fan Not Working

Check physical cable connection to fan

Internal Communication Error

Power cycle inverter (OFF 30 seconds, then ON)

AC Voltage Surge

Check AC connection to inverter — all terminals secure

DC SPD Not Functioning

Validate DC SPD board is installed per installation guide

AC SPD Not Functioning

Validate AC SPD board is installed per installation guide

AC Terminal Temperature Critical

Verify AC lugs are properly installed

Inverter Temperature Critical

Verify inverter clearances per installation guide (200mm top minimum)

Ground Current RCD

Ground Current - RCD (2xA/2x25/2x26, 3P 8x2B/8x2C/8x39)

Shock hazard. Inverter switch OFF, wait 5 minutes for capacitors, isolate AC, di…

RCD Current Surge

RCD Current Surge (3P, 8x51)

Follow the isolation fault procedure, string by string isolation with megger tes…

RCD Sensor Error (2x1C, 3P 124/8x5B)

Power cycle the inverter fully.

Arc Fault Detected (147/150/151, 3x11/2x96/2x97)

Inspect DC wiring for loose MC4s, damaged insulation and corroded joints before …

Arc Detector Self-Test Failed (2x98)

Power cycle fully (DC and AC).

AC Voltage Too High

AC Voltage Too High (31/33, 2x1F/2x21, 3P 64-66)

Verify the country grid code is correct (UK G98/G99).

AC Voltage Too Low

AC Voltage Too Low (32/41, 2x20/2x29, 3P 61-69)

Check for a tripped supply breaker or area outage.

AC Current Surge

AC Current Surge (9/13, 2x9/2xD)

Check the AC connection to the inverter.

AC Freq Too High

AC Frequency Too High (34, 2x22, 3P 79-81)

Verify the country grid setting, then allow automatic reconnection.

AC Freq Too Low

AC Frequency Too Low (35, 2x23, 3P 82-84)

Verify the country grid setting, then allow automatic reconnection.

Islanding Detected (40, 2x28, 3P 87/89)

Check the board for tripped breakers and confirm whether there is an area outage…

Grid Sync Error

Grid Sync Error (3P, 78/8x2D)

Measure and log grid voltage and frequency stability at the inverter.

Line-to-Line Voltage Out of Range (3P, 70/71, 8x25/8x26)

Verify the country setting, then measure phase to phase voltages.

Wrong AC Connection

Wrong AC Connection (3P, 112/8x4F)

Swap L1 and L2, or L2 and L3, at the inverter AC terminals and re-test.

AC Over Current

AC Over Current (3P, 91-93, 8x3A-8x3C)

Power cycle the inverter.

DC Injection (36, 2x24, 3P 72-75)

Power cycle the inverter and record how often it occurs.

No Country Selected

No Country Selected (44, 2x2C)

Select the correct country grid code (UK G98/G99) in SetApp or the LCD menu and …

DC Voltage Out of Range (145/146, 2x91/2x92, 3P 102/103)

Power cycle the inverter.

Temperature Too Low (3P, 105/8x48)

Check ambient temperature is within the datasheet range.

Faulty AC Relay (3P 122/8x59)

Power cycle the inverter once.

Hardware Error (16/149/153 and 3P family)

Full power cycle, record the exact code, sub-code and time.

Software Error (multiple codes)

Power cycle the inverter.

Server Communication Loss (S_ERR)

Check the router and internet connection.

Meter Comms Loss

No Communication With Meter (RS485)

Check connections on the inverter communication board.

Optimizer Not Communicating (P_OK count low)

Run pairing (monitoring Layout right-click, or SetApp/LCD).

Module Mismatch

Module Voltage Mismatch (bypass diode)

Compare module voltage in monitoring Analysis against the panel Vmpp spec.

SenseConnect Safety Lock (S-Series)

Check inverter firmware is 4.17 or higher, upgrade if lower.

Battery Comms Loss

No Communication With Battery

Verify battery DC and comms connections at both ends.

Battery Breaker Tripped

Battery Circuit Breaker Tripped

Full power down in the documented order, then power up in reverse order.

G100 Restriction

G100 Export Restriction Active (UK)

Resolve any meter communication fault first, export limiting needs the meter.

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