Mitsubishi Electric Melservo-J4 Instruction Manual page 43

Alarm No.: 20 Name: Encoder normal communication error 1
 An error occurred in the communication between an encoder and servo amplifier.
Alarm content
Detail Detail name Cause
No.
20.1 Encoder normal (1) An encoder cable is
communication malfunctioning.
- Receive data
error 1
(2) The external conductor
of the encoder cable is
not connected to the
ground plate of the
connector.
(3) The parameter setting
of communication
method is incorrect.
[A]: [Pr. PC22]
[B] [WB] [RJ010] [GF]:
[Pr. PC04]
(4) In the parallel drive
system, the setting of
[Pr. PF40] is incorrect.
(5) The servo amplifier is
malfunctioning.
(6) An encoder is
malfunctioning.
(7)
device caused it.
20.2 Encoder normal Check it with the check method for [AL. 20.1].
communication
- Receive data
error 2
20.3 Encoder normal
communication
- Receive data
error 3
Check method
Check if the encoder
cable is disconnected or
shorted. When you use
an A/B/Z-phase
differential output linear
encoder, check the wiring
of the linear encoder.
Check if it is connected.
Check the parameter
setting.
Check the parameter
setting.
Replace the servo
amplifier, and then check
the repeatability.
Replace the servo motor
or linear encoder, and
then check the
repeatability.
Something near the Check the noise, ambient
temperature, vibration,
etc.
Check result
It has a failure.
It has no failure.
It is not connected.
It is connected.
The setting is incorrect.
The setting is correct.
The setting is incorrect.
The setting is correct.
It is not repeatable.
It is repeatable.
It is not repeatable.
It is repeatable.
There is a problem in the
surrounding.
1 TROUBLESHOOTING FOR SERVO AMPLIFIER (DRIVE UNIT)
Action Target
Repair or replace the [A]
cable. [B]
[WB]
Check (2).
[RJ010]
[GF]
Connect it correctly.
Check (3).
Set it correctly.
Check (4).
Set it correctly.
Check (5).
Replace the servo
amplifier.
Check (6).
Replace the servo motor
or linear encoder.
Check (7).
Take countermeasures
against its cause.
1.4 Remedies for alarms
1
41