Mitsubishi Electric MELSERVO MR-J4-B-RJ Series, Instruction Manual

Page: 86 / 174

1. TROUBLESHOOTING FOR SERVO AMPLIFIER (DRIVE UNIT)
1 - 79
Alarm No.: 7A Name: Parameter setting error (safety observation function)
Alarm content A parameter of the functional safety unit failed.
Detail
No.
Detail name Cause Check method Check result Action Target
7A.4 Functional
safety unit
combination
error (safety
observation
function)
(1) A combination of
functional safety unit
and servo amplifier is
incorrect.
Check if correct
combination of servo
amplifier is connected. A different servo
amplifier is
connected. Return to the servo
amplifier which was
combined with the
functional safety unit
and was set the
safety observation
function, or initialize
the setting. [A]
[B]
[GF]
Alarm No.: 7B Name: Encoder diagnosis error (safety observation function)
Alarm content Error occurred in encoder.
Detail
No.
Detail name Cause Check method Check result Action Target
7B.1 Encoder
diagnosis error
1 (safety
observation
function)
(1) An encoder cable is
malfunctioning.
Check if the encoder
cable is disconnected
or shorted. It has a failure. Repair or replace
the cable. [A]
[B]
[GF]
It has no failure. Check (2).
(2) An encoder is
malfunctioning.
Replace the servo
motor, and then check
the repeatability. It is not repeatable. Replace the servo
motor.
It is repeatable. Check (3).
(3) The functional safety
unit is malfunctioning.
Replace the functional
safety unit, and then
check the
repeatability. It is not repeatable. Replace the
functional safety unit.
It is repeatable. Check (4).
(4) The servo amplifier is
malfunctioning.
Replace the servo
amplifier, and then
check the
repeatability. It is not repeatable. Replace the servo
amplifier.
It is repeatable. Check (5).
(5) Something near the
device caused it.
Check the noise,
ambient temperature,
vibration, etc. It has a failure. Take
countermeasures
against its cause.
7B.2 Encoder
diagnosis error
2 (safety
observation
function)
(1) Check it with the check method for [AL. 7B.1].
7B.3 Encoder
diagnosis error
3 (safety
observation
function)
(1)
7B.4 Encoder
diagnosis error
4 (safety
observation
function)
(1) Ambient temperature of
the encoder has
exceeded 40 °C.
Check the ambient
temperature of the
encoder. It is over 40 ˚ C. Lower the ambient
temperature. [A]
[B]
[GF]
It is 40 ˚ C or less. Check (2).
(2) Ambient temperature of
the encoder is less than
0
˚ C.
Check the ambient
temperature of the
encoder. It is 0 ˚ C or less. Increase the ambient
temperature.
It is 0 ˚ C or more. Check (3).
(3) Servo motor is
overloaded.
Check the effective
load ratio. The effective load
ratio is high. Reduce the load or
review the operation
pattern.
The effective load
ratio is small. Check (4).
(4) The thermal sensor in
the encoder is
malfunctioning.
Replace the servo
motor, and then check
the repeatability. It is not repeatable. Replace the servo
motor.
It is repeatable. Check (5).
(5) The functional safety
unit is malfunctioning.
Replace the functional
safety unit, and then
check the
repeatability. It is not repeatable. Replace the
functional safety unit.