Mitsubishi Electric Melservo-J4 Instruction Manual page 102

Alarm No.: 8E
Alarm content
Detail Detail name
No.
8E.6 Modbus RTU
communication
receive error
8E.7 Modbus RTU
communication
message frame
error
8E.8 Modbus RTU
communication
CRC error
Alarm No.: 88888
Alarm content
Detail Detail name
No.
88._/ Watchdog
8888._
1 TROUBLESHOOTING FOR SERVO AMPLIFIER (DRIVE UNIT)
100
1.4 Remedies for alarms
Name: USB communication error/serial communication error/Modbus RTU communication error
 A communication error occurred between the servo amplifier and a personal computer/controller.
 An error occurred in USB communication, serial communication (Mitsubishi Electric general-purpose
AC servo protocol), or Modbus RTU communication.
Cause Check method
(1) The setting of the Check the setting of the
controller, servo controller, servo
amplifier, etc. is amplifier, etc. (such as
incorrect. communication protocol
selection, baud rate,
parity).
(2) A communication cable Check the
is malfunctioning. communication cable,
and then check the
repeatability.
(3) The servo amplifier is Replace the servo
malfunctioning. amplifier, and then check
the repeatability.
(1) The communication Check if transmission
protocol is failure. data conforms the
communication protocol.
(2) The setting of the Check the setting of the
controller, servo controller, servo
amplifier, etc. is amplifier, etc. (such as
incorrect. communication protocol
selection, baud rate,
parity).
Check it with the check method for [AL. 8E.7].
Name: Watchdog
 [RJ010]: MR-J3-T10 came off.
 A part such as CPU is malfunctioning.
Cause Check method
(1) The MR-J3-T10 came Check if [AL. 74 Option
off during the CC-Link card error 1] occurred
IE communication. with alarm history.
(2) A part in the servo Replace the servo
amplifier is failure. amplifier, and then check
the repeatability.
Check result Action
It is incorrect. Review the settings.
It is correct. Check (2).
It is not repeatable. Replace the
communication cable.
It is repeatable. Check (3).
It is not repeatable. Replace the servo
amplifier.
It is not conforming. Modify the transmission
data according to the
communication protocol.
It is conforming. Check (2).
It is incorrect. Review the settings.
Check result Action
It is occurring. Check it with the check
method for [AL. 74].
It did not occur. Check (2).
It is not repeatable. Replace the servo
amplifier.
Target
[A]
Target
[RJ010]
[A]
[B]
[WB]
[RJ010]
[GF]