Inverter Error & Fault Code Resolver

Solar Inverter Fault Diagnostics

Instant diagnostic steps, causes, and field solutions for Inverex, Knox, Huawei, and Growatt error codes.

Ask PakShamsi AI Assistant
All Growatt SPF Huawei SUN2000 Inverex Nitrox Knox Krypton Solis Inverters
Error 18

Inverter Output Short Circuit

Growatt SPF
high Severity
Root Cause:

High surge load (like heavy motor/AC startup) or wiring short in main DB.

Field Solution:

Isolate household sub-breakers one by one to find faulted circuit.

Alarm 2064

Device Abnormal (Internal Temperature High)

Huawei SUN2000
medium Severity
Root Cause:

Inverter installed in direct sunlight or cooling fins obstructed by dust.

Field Solution:

Install shade canopy over inverter and clean heatsink aluminum fins.

F01

DC Polarity Reverse / Bus Overvoltage

Inverex Nitrox
high Severity
Root Cause:

DC string reverse connection or sudden solar surge spike.

Field Solution:

Turn off DC isolator switch. Verify string voltage with multimeter before reconnecting.

F52

CT Sensor / Meter Communication Failure

Inverex Nitrox
medium Severity
Root Cause:

RS485 communication cable disconnected between inverter and zero-export smart meter.

Field Solution:

Check twisted pair polarity (A+ and B-) on COM port pin 5 and pin 6.

Fault 09

Bus Soft Start Failed

Knox Krypton
critical Severity
Root Cause:

Internal DC pre-charge relay did not engage or battery voltage is under 42V.

Field Solution:

Reboot inverter from AC and Battery simultaneously. Verify battery state of charge.

AL-01

Grid Over-Voltage (OV-G-V01)

Solis Inverters
medium Severity
Root Cause:

Utility grid voltage exceeded upper protection threshold (265V+).

Field Solution:

Verify grid voltage with multimeter across AC terminals. Adjust DISCO grid tolerance parameters if permitted.