YASKAWA MP2000 Series User Manual page 167

7.2 Motion Command Details
7.2.3 Zero Point Return (ZRET)
[ f ] DEC1 + LMT + ZERO Signal Method (OW3C = 5)
With this method, the machine's position is confirmed by the ON/OFF status of the DEC1, Reverse Limit, and Forward
Limit signals and the retracting operation is performed automatically, so the zero point return is always performed with
the same conditions.

Starting the Zero Point Return in Region A
1.
Travel is started in the positive direction at the speed specified by the Speed Reference Setting (setting
parameter OL10).
2.
When the falling edge of the DEC1 signal is detected, the axis decelerates to a stop.
3.
After decelerating to a stop, the axis travels in the reverse direction at the Approach Speed (setting
parameter OL3E).
4.
When the rising edge of the DEC1 signal is detected, the axis decelerates to a stop.
5.
After decelerating to a stop, the axis travels in the forward direction at the Creep Rate (setting param-
eter OL40).
6.
After the falling edge of the DEC1 signal is detected, the position is latched when the rising edge of the
ZERO signal is detected.
7.
The axis moves from the latched position by the distance set in the Zero Point Return Travel Distance
(setting parameter OL42) and stops. The machine coordinate system is established with this final
position as the zero point.
(DI_5 or OW 05, bit 8)
Zero Point Return Reverse
Run Side Limit Signal
(OW 05, bit 9)
Zero Point Return Forward
Run Side Limit Signal
(OW 05, bit 10)
 If an OT signal is detected during the zero point return operation, an OT alarm will occur.
 The command will end in an error at the start of the Zero Point Return operation if the status of the DEC1, For-
ward Limit, and Reverse Limit signals is not the same as the status shown in the diagram above.
7-28
Region A
Speed Reference
Setting
(OL
N-OT
(DI_4)
Start
DEC1
ZERO signal
(DI_2)
Region B
Region C
10)
ZERO signal
latch at this point
Creep Rate
(OL 40)
Zero Point Return Travel Distance
Approach Speed (OL
Region D Region E
End
3E)
P-OT
(DI_3)