Mitsubishi Electric Melservo-J3 Series MR-J3-B, Instruction Manual

Page: 616 / 802

16 - 61
16. INDEXER POSITIONING OPERATION
16.9 Home position return mode
16.9.1 Outline of home position return
Home position return is performed to match the command coordinates with the machine coordinates. In the
incremental system, home position return is required every time input power is switched on. In the absolute
position detection system, once home position return is done at the time of installation, the current position is
retained if power is switched off. Hence, home position return is not required when power is switched on again.
This servo amplifier has the home position return methods given in this section. Choose the most appropriate
method for your machine structure and application.
This servo amplifier has the home position return automatic return function which executes home position
return by making an automatic return to a proper position if the machine has stopped beyond or at the
proximity dog. Manual motion by jog operation or the like is not required.
(1) Home position return types
Choose the optimum home position return according to the machine type, etc.
Type Home position return method Features
Torque limit changing dog
type home position return
With deceleration started at the front end of a
proximity dog, the position where the first
Z-phase signal is given past the rear end of the dog or
a motion has been made over the home position shift
distance starting from the Z-phase signal is defined as
a home position.
General home position return method using a
proximity dog.
Repeatability of home position return is
excellent.
The machine is less burdened.
Used when the width of the proximity dog can
be set greater than the deceleration distance of
the servo motor.
Torque limit value by the parameter No.PC35
(Internal torque limit 2) becomes effective while
the servo motor at stop.
Torque limit changing
data setting type home
position return
An arbitrary position is defined as a home position.
No proximity dog required.
Torque limit value turns to “0” in the home
position return mode.
(2) Home position return parameter
When performing home position return, set each parameter as follows.
(a) Choose the home position return method with parameter No.PC02 (Home position return type).
Home position return method
0:
1:
2:
3:
4:
5: Not used in indexer postioning operation.
6:
7:
8:
9:
A:
C: Torque limit changing dog type
D: Torque limit changing data setting type
0
Parameter No.PC02
0 0