There are Err30, Err31 or Err32 alarm on the AC servo driver(amplifier), these means UVW signal problem of the servo motor encoder.

Causes could be:

1-      The AC servo motor feedback signal cable of UVW is short circuit or broken, or the isolating cable is not connected to the earth.

2-      The encoder of the AC servo motor is damaged.

3-      The port of the AC servo driver connecting to the encoder has problem.

Solutions:

1-      Fix or change the AC servo motor feedback signal cable.

2-      Change the AC servo motor.

3-      Check the encoder port of the AC servo driver, if it is broken, send back for repair.

DA98B AC servo driver specification:

http://www.cncmakers.com/cnc/controllers/Servo_Motor_Driver/da98b.html