FoxESS
Eps Relay Fault
EPS Relay Fault
The EPS (Emergency Power Supply / backup) relay has failed or cannot operate correctly.
Common causes
Relay hardware failureEPS wiring not connectedFirmware issue
What to check
STEP 1
Check EPS output wiring is connected to inverter EPS terminals (not AC output). Confirm EPS is enabled in app
STEP 2
Power cycle inverter. Verify EPS relay clicks audibly when switching to backup mode
Escalate if
Relay fault persists and EPS wiring is correct — hardware fault, escalate
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