Home Position Return - Mitsubishi Electric MR-J4-10B(-RJ) Instruction Manual

14. USING A LINEAR SERVO MOTOR

14.3.3 Home position return

(1) Incremental linear encoder
CAUTION
(a) When the linear encoder home position (reference mark) exists in the home position return direction
When an incremental linear encoder is used, the home position is the position per 1048576 pulses
(changeable with the third digit of [Pr. PL01]) with reference to the linear encoder home position
(reference mark) passed through first after a home position return start. Change the setting value of
[Pr. PL01] according to the linear encoder resolution.
The following shows the relation between the stop interval at the home position return and the linear
encoder resolution. For example, when the linear encoder resolution is 0.001 μm and the parameter
for the stop interval at the home position return, [Pr. PL01], is set to "_ 5 _ _" (16777216 pulses), the
stop interval is 16.777 mm. The value inside a bold box indicates the recommended stop interval for
each linear encoder resolution.
Linear encoder
resolution [µm]
Pr. PL01
Stop interval
[pulse]
_ 0 _ _ 8192
_ 1 _ _ 131072
_ 2 _ _ 262144
_ 3 _ _ 1048576
_ 4 _ _ 4194304
_ 5 _ _ 16777216
_ 6 _ _ 67108864
POINT
The incremental linear encoder and the absolute position linear encoder have
different reference home positions at the home position return.
If the resolution or the stop interval (the third digit of [Pr. PL01]) of the linear
encoder is large, it is very dangerous since the linear servo motor may crash into
the stroke end.
[Pr. PL01]
0.001 0.005 0.01
0.008 0.041 0.082
0.131 0.655 1.311
0.262 1.311 2.621
1.049 5.243 10.486
4.194 20.972 41.943
16.777 83.886 167.772
67.109 335.544 671.089 1342.177
Stop interval setting at the home position return
Setting
Stop interval [pulse]
value
0 8192
1 131072
2 262144
3 1048576 (initial value)
4 4194304
5 16777216
6 67108864
0.02 0.05 0.1
0.164 0.410 0.819
2.621 6.554 13.107
5.243 13.107 26.214
20.972 52.429 104.858
83.886 209.715 419.430
335.544 838.861 1677.722
3355.443 6710.886 13421.773 33554.432 67108.864 134217.728
14 - 20
0.2 0.5 1
1.638 4.096 8.192
26.214 65.536 131.072
52.429 131.072 262.144
209.715 524.288 1048.576
838.861 2097.152 4194.304
3355.443 8388.608 16777.216
[Unit: mm]
2
16.384
262.144
524.288
2097.152
8388.608
33554.432