ServoMR-J4Verified · sol.ls-electric.com
MR-J4 AL.8E — Serial comm error
Alarm — operational, inspection needed· AUTO-RESET
CAUSE
Why does it occur?
RS-422/485 communication timeout or parity error.
REMEDY · Step by step
How to fix it?
Check the wiring, termination resistor, and baud rate.
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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