Mitsubishi Electric MELSERVO-J4 series, Instruction Manual

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16 FULLY CLOSED LOOP SYSTEM
16.3 Operation and functions
Confirmation of load-side encoder position data
Check the load-side encoder mounting and parameter settings for any problems.
Depending on the check items, MR Configurator2 may be used.
Refer to the following for the data displayed on the MR Configurator2.

Page 533 About MR Configurator2
When checking the following items, the fully closed loop control mode must be set. For the setting of control mode, refer to the
following.

Page 522 Selection of fully closed loop system
No. Check item Confirmation method and description
1 Read of load-side encoder position data With the load-side encoder in a normal state (mounting, connection, etc.), the load-side cumulative
feedback pulses value is counted normally when the load-side encoder is moved.
When it is not counted normally, the following factors can be considered.
1. An alarm occurred.
2. The installation of the load-side encoder was not correct.
3. The encoder cable was not wired correctly.
2 Read of load-side encoder home
position (reference mark, Z-phase) With the home position (reference mark, or Z-phase) of the load-side encoder in a normal condition
(mounting, connection, etc.), the value of load-side encoder information 1 is cleared to 0 when the home
position (reference mark, or Z-phase) is passed through by moving the load-side encoder.
When it is not cleared, the following factors can be considered.
1. The installation of the load-side encoder was not correct.
2. The encoder cable was not wired correctly.
3 Confirmation of load-side encoder
feedback direction
(Setting of load-side encoder polarity) Confirm that the directions of the cumulative feedback pulses of servo motor encoder (after gear) and the
load-side cumulative feedback pulses are matched by moving the device (load-side encoder) manually in
the servo-off status. If mismatched, reverse the polarity.
4 Setting of load-side encoder electronic
gear When the servo motor and load-side encoder operate synchronously, the servo motor-side cumulative
feedback pulses (after gear) and load-side cumulative feedback pulses are matched and increased.
If mismatched, review the setting of fully closed loop control feedback electronic gear ([Pr. PE04], [Pr.
PE05], [Pr. PE34], and [Pr. PE35]) with the following method.
1) Check the servo motor-side cumulative feedback pulses (before gear).
2) Check the load-side cumulative feedback pulses.
3) Check that the ratio of above 1) and 2) has been that of the feedback electronic gear.
Servo motor
Linear
encoder
+
-
Servo motor-side cumulative
feedback pulses (after gear)
3) Electronic
gear
2) Load-side cumulative
feedback pulses
Command
1) Servo motor-side cumulative
feedback pulses (before gear)