Mitsubishi Electric RD77MS16, User Manual

Page: 441 / 644

12 DATA USED FOR POSITIONING CONTROL
12.3 Basic Setting
439
12
[Pr.50] Setting for the movement amount after near-point dog ON
When using the count method 1 or 2, set the movement amount to the home position after the near-point dog signal turns ON.
(The movement amount after near-point dog ON should be equal to or greater than the sum of the "distance covered by the
deceleration from the home position return speed to the creep speed" and "distance of movement in 10 ms at the home
position return speed".)
■ Example of setting for "[Pr.50] Setting for the movement amount after near-point dog ON"
Assuming that the "[Pr.8] Speed limit value" is set to 200 kpulses/s, "[Pr.46] Home position return speed" to 10 kpulses/s,
"[Pr.47] Creep speed" to 1 kpulses/s, and deceleration time to 300 ms, the minimum value of "[Pr.50] Setting for the
movement amount after near-point dog ON" is calculated as follows:
[Pr.51] Home position return acceleration time selection
Set which of "acceleration time 0 to 3" to use for the acceleration time during home position return.
0: Use the value set in "[Pr.9] Acceleration time 0".
1: Use the value set in "[Pr.25] Acceleration time 1".
2: Use the value set in "[Pr.26] Acceleration time 2".
3: Use the value set in "[Pr.27] Acceleration time 3".
[Pr.52] Home position return deceleration time selection
Set which of "deceleration time 0 to 3" to use for the deceleration time during home position return.
0: Use the value set in "[Pr.10] Deceleration time 0".
1: Use the value set in "[Pr.28] Deceleration time 1".
2: Use the value set in "[Pr.29] Deceleration time 2".
3: Use the value set in "[Pr.30] Deceleration time 3".
[Pr.1] setting value Value set with the engineering tool (unit) Value set with a program (unit)
0: mm 0 to 214748364.7 (

m) 0 to 2147483647 (

10
-1 
m)
1: inch 0 to 21474.83647 (inch) 0 to 2147483647 (

10
-5
inch)
2: degree 0 to 21474.83647 (degree) 0 to 2147483647 (

10
-5
degree)
3: pulse 0 to 2147483647 (pulse) 0 to 2147483647 (pulse)
Deceleration time:
Tb = 300 ms
Movement amount for 10 ms
at home position return speed.
Actual deceleration time: t = Tb
×
t
Vz
Vp
[Home position return operation]
[Deceleration distance]
1
2
×
=
Vz
1000
Tb × Vz
Vp
× t
=
Vz
2000
×
300
×
10
×
10
3
200
×
10
3
×
10
×
10
3
2000
=
= 175
+ 0.01
×
Vz
+ 0.01 × Vz
+ 0.01
×
10
×
10
= 75 + 100
[Pr.8] Speed limit value: Vp = 200 kpulses/s
3
*: "[Pr.50] Setting for the movement amount
after near-point dog ON" should be equal to
or larger than 175.
[Pr.46] Home position return speed:
Vz = 10 kpulses/s
[Pr.47] Creep speed:
Vc = 1 kpulses/s