This error is displayed from version 1.9.2 on and means that N and L are switched, which will subsequently damage and burn the motherboard.
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To prevent this please follow Etrel INCH electrical and physical installation guides and the on the protection element, located inside the INCH charger.
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3 phase connection:
correct:
wrong (L1 and N switched):
wrong (L2 and N switched):
wrong (L3 and N switched):
Please measure between each phase and ground. Results:
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1 phase connection:
correct:
wrong (switched L1 and N):
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