Mitsubishi Electric MELSERVO-J4 series Instruction Manual page 411

14. USING A LINEAR SERVO MOTOR
3) Linear servo motor movement (when FLS (Upper stroke limit) or RLS (Lower stroke limit) is off)
When FLS or RLS is off at servo-on, the magnetic pole detection is carried out as follows.
(b) For the absolute position linear encoder
Perform the magnetic pole detection in the following procedure.
1) Set [Pr. PL01 Linear servo motor/DD motor function selection 1] to "_ _ _ 1" (Magnetic pole
detection at first servo-on).
2) Execute the magnetic pole detection. (Refer to (3) (a) 1), 2) of this section.)
Magnetic pole detection
start position
RLS
The linear servo motor reciprocates several times and returns
to the magnetic pole detection start position to complete the
magnetic pole detection and to go into the servo-lock status.
At this time, there may be a gap, approximately a quarter of
the pitch against magnetic pole, from the start position.
Note. For the pitch against magnetic pole, refer to (3) (a) 2) Note 2 of this section.
POINT
When you use an absolute position linear encoder with the following timings, the
magnetic pole detection will be required.
When the system is set up (at the first startup of equipment)
After a servo amplifier is replaced
After a linear servo motor (primary-side or secondary-side) is replaced
After a linear encoder (scale or head) is replaced or its position is adjusted
When the absolute position linear encoder is used, if a gap is generated to the
positional relation between the linear encoder and the linear servo motor,
perform the magnetic pole detection again.
[Pr. PL01]
1
The linear servo motor moves to a
magnetic pole detection start position
upon servo-on, and the magnetic pole
detection is executed.
Servo-on
(Note)
Magnetic pole detection completion position
Magnetic pole detection at first servo-on (Initial value)
14 - 16
position
FLS