Mitsubishi Electric MELSEC-L LD75P User Manual page 647

(2) Troubleshooting when a motor does not rotate
Check items and corrective actions for troubleshooting when a motor does not rotate are described below.
The following signals must be ON for the LD75 to operate (excluding when the positioning test function of GX Works2 is
used).
• LD75 READY signal (X0)
• Drive unit READY signal
• Upper limit signal and Lower limit signal
The status of the drive unit READY signal and upper/lower limit signals can be checked in b0 to b2 of "[Md.30] External I/O
signal".
Check item
Are the LD75 READY signal (X0), drive unit READY
signal, and upper/lower limit signals ON?
Is there an error in the LD75? (ERR. LED is on or
flashing)
Is the drive unit powered ON?
Is there an error in the drive unit?
Is the wiring between the LD75 and drive unit correct?
Is the wiring between the drive unit and motor
correct?
Is the value in "[Md.20] Current feed value" changed
after positioning control is performed?
Is the number of the input pulses for monitoring
changed after positioning control is performed?
Isn't the value in "[Md.26] Axis operation status" "1:
Stopped"?
Does the setting of the pulse output mode meet the
specifications of the drive unit?
Does the output logic setting of the command pulse
signal meet the specifications of the drive unit?
*1 This check item applies only for the drive unit having a monitor function for the number of input pulses.
If a motor does not rotate even after the above items are checked, the possible cause is a hardware failure.
Please consult your local Mitsubishi representative.
Review and correct the program and wiring so that all the LD75 READY signal (X0), drive unit READY
signal, and upper/lower limit signals turn ON.
Check the error code and take a corrective action.
Power on the drive unit.
Check the error code of the drive unit and take a corrective action.
Check the wiring between the LD75 and drive unit, and correct it.
Check the wiring between the drive unit and motor, and correct it.
Review the start program.
Refer to the drive unit operating manual and check that the function to suppress the motor rotation is
*1
not working.
• Review the stop program.
• Check that the stop signal (STOP) is not input.
Set "[Pr.5] Pulse output mode" so that it satisfies the specifications of the drive unit.
Set the value of the logic selection of the command pulse signal ([Pr.23] Output signal logic selection:
b0) so that it satisfies the specifications of the drive unit.
CHAPTER 15 TROUBLESHOOTING
Action
15
645