THOR has detected absent or high-resistance earth connection. Charger will not operate for safety.
Common causes
PE (earth) conductor not connected at THOR terminalBroken earth conductorHigh resistance earth joint
What to check
STEP 1
Check PE (yellow/green) conductor is connected at THOR terminal block. Measure earth continuity from THOR housing to consumer unit earth bar — must be <1Ω
STEP 2
Check AC cable for damage. Inspect PE connection at consumer unit earth bar
Escalate if
Earth confirmed connected and continuity <1Ω but fault persists — THOR earth detection circuit fault, escalate. Do not operate without a confirmed earth
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