How do I fix RCD Sensor Error (2x1C, 3P 124/8x5B) on a SolarEdge?

Power cycle the inverter fully. Then: Record the exact code and time.

SolarEdge

Error 28

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

Internal RCD measurement circuit failed its wake-up self test. Internal fault, not site leakage.

Common causes

Internal hardware fault

What to check

STEP 1

Power cycle the inverter fully.

STEP 2

Record the exact code and time.

Escalate if

Persists after power cycle, warranty replacement likely

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