PLCFX5UVerification pending — cross-check with the official manual
FX5U 2301H — Security key authentication error
Alarm — operational, inspection needed
CAUSE
Why does it occur?
• The program is locked by the security key, but the security key is not written in the CPU module.
REMEDY · Step by step
How to fix it?
Stop
Do not reset repeatedly before identifying the cause. Repeated resets while ignoring a trip/alarm can cause secondary damage (IGBT failure, motor winding damage, etc.).
SOURCE
Related manual page
Summary based on the official Mitsubishi Electric manual. For accurate and complete information, always consult the official manual.
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