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100043AlphaESS · SMILE-G3

100043 on an AlphaESS SMILE-G3: Output_overload - backup output overload

Short answer

On an AlphaESS inverter, 100043 means: Output_overload - backup output overload. The inverter keeps running with some functions stopped.

Reviewed 24 September 2026 · 1 source

What it means

The manual says: Output_overload - backup output overload.

Likely causes:

  • Backup load exceeds rated power.

Is it safe?

Does the inverter stop?Partly
SeverityFault — clears by itself when the condition goes

The inverter keeps running with some functions stopped.

Resetting itself: restart after load reduced.

Manual reset: Restart of the inverter by installer (power-down/power-up sequence) if it does not clear.

What you can check

  • Read the code in the AlphaCloud app/web portal (or the LED pattern on the unit) and note it with the time. Check the inverter's AC isolator and the consumer-unit breaker for the inverter are ON. Report persistent or repeating codes to your installer - AlphaESS says 'call the service' if it does not clear. During a power cut, switch off large appliances (kettle, oven, heaters) on backed-up circuits, then let the system recover.

What the engineer will check

  • Check the backup loads against the rated output (5 kW / 3.68 kW); re-allocate circuits.

Who to ask for: MCS PV/battery installer familiar with AlphaESS.

Certification: MCS-certified solar PV installer (MIS 3002) or competent electrician (BS 7671 / Part P in England & Wales); DC work only by PV-trained installer.

What you might notice

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 24 September 2026