Mitsubishi Electric MDS-B-SPJ2 Series Specification Manual page 150

(5) Alarm No.
[Details] There was an A, B or Z phase signal error for the orientation 1024P/rev encoder.
Investigation items
1 Check the spindle
parameter (SP037:
SFNC5) setting.
2 Jiggle the connector
(spindle drive unit side
and detector side) to
see whether it is
coming loose.
3 Turn the power OFF,
and check the detector
cable connection with
a tester.
11. Troubleshooting
21 : NO SIGNAL DETECTION (ENC)
Investigation results
Bit0 is set to "1" even though
encoder orientation is not executed.
No particular problem.
Connector came (was coming) loose. Install correctly.
Connector did not come (was not
coming) loose.
The connection is faulty, or there is a
broken wire.
The connection is normal.
Set the correct value.
Investigate item 2, and carry out the
appropriate measures.
Investigate item 3, and carry out the
appropriate measures.
Replace the detector cable. Correctly
connect the cable.
Replace the spindle drive unit or
detector.
11 − 6
Remedy