Description of Fault Codes
‑73‑
Cause
Confirming Method
Solution
An error occurs on the
communication between the
servo drive and the encoder.
Check whether the value of
H0b.28 is not 0.
1. Check whether H00.00
(Motor code) is set
properly.
2. Check whether the
encoder cable is
connected properly.
3. Check whether the servo
drive and motor are
grounded properly. You
can wind a magnetic ring
on the encoder cable to
reduce interference.
● E740.3: Absolute encoder single‑turn calculation error
Cause:
The encoder is faulty.
Cause
Confirming Method
Solution
An encoder fault occurs.
Check whether bit7 of
H0b.28 is set to 1.
1. Check whether the
encoder version (H00.04)
is proper.
2. Check whether the
encoder cable is proper.
3. Replace the motor.
● E740.6: Encoder data write error
Cause:
The attempt to write the encoder data fails.
Cause
Confirming Method
Solution
An error occurs when writing
the position offset after
angle auto‑tuning.
Replace with a new encoder
cable. If the fault no longer
occurs after cable
replacement, it indicates the
original encoder cable is
damaged. Keep the motor in
a certain position, power on
the system several times
and observe the change of
H0b.17 (Electrical angle).
The electrical angle
deviation should be within
±30° when the motor
position does not change.
Replace with a new encoder
cable. If the fault persists
after the encoder cable is
replaced, the encoder may
be faulty. In this case,
replace the servo motor.