How do I clear or fix error 73?

Power down the inverter, wait 5 minutes for capacitors to discharge, then restart. If the fault recurs immediately or repeatedly, record the exact code and contact your installer or the manufacturer's service line.

Felicity inverter error 73 (F73)

CT or Hall open circuit fault

Also displayed as F73 on some models.

Fault — the inverter cuts its output and the red LED stays solid until the fault is cleared.

T-REX-50KHP3G01

InverterFault

What it means

CT or Hall open circuit fault — Current sensing device is faulty, check CT or Hall element connections.

Cause: A current-sensing device (CT or Hall-effect sensor) reads open circuit — one of the inverter's current measurement paths is broken, so protection can no longer rely on it.

How to fix it

Power down the inverter, wait 5 minutes for capacitors to discharge, then restart.
If the fault recurs immediately or repeatedly, record the exact code and contact your installer or the manufacturer's service line.

Source: t-rex-25-50khp3g01-user-guide-en.pdf, p.48

Frequently asked questions

What does error 73 mean on a Felicity inverter?: 73 means: CT or Hall open circuit fault. A current-sensing device (CT or Hall-effect sensor) reads open circuit — one of the inverter's current measurement paths is broken, so protection can no longer rely on it.
Is error 73 a fault or a warning?: 73 is a fault code: the inverter cuts its output and the red LED stays solid until it is cleared.
How do I clear or fix error 73?: Power down the inverter, wait 5 minutes for capacitors to discharge, then restart. If the fault recurs immediately or repeatedly, record the exact code and contact your installer or the manufacturer's service line.

Related error codes

Other codes on the T-REX-50KHP3G01

All T-REX-50KHP3G01 codes

Prefer the full written guide? Read the complete Felicity inverter error-code guide

Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.