Mitsubishi Electric RD77MS2 User Manual page 45

Precautions during operation
• The error "Start at home position" (error code: 1940H) will occur if another machine home position return is attempted
immediately after a machine home position return completion when the home position is in the near-point dog ON position.
• The following shows the operation when a machine home position return is started from the near-point dog ON position.
■Operation when a machine home position return is started from the near-point dog ON
position
V
[Pr.44] Home position return direction
[Pr.47] Creep speed
3. 1.
2.
[Pr.46] Home position return speed
ON
Near-point dog OFF
Zero signal
1.
The machine moves in the opposite direction against of home position return at the home position return speed.
2.
The machine begins decelerating when the first zero signal is detected.
3.
After deceleration stop, the operation moves in direction of home position return at the creep speed, and then stops at
the zero signal to complete the machine home position return.
After 1., when the zero signal is in the near-point dog ON position, deceleration stop (2.) is started at the zero
signal without waiting for the near-point dog OFF.
• When the stop signal stops the machine home position return, carry out the machine home position return again. When
restart command is turned ON after the stop signal stops the home position return, the error "Home position return restart
not possible" (error code: 1946H) will occur.
• The home position return retry will not be performed regardless of setting set in "[Pr.48] Home position return retry" in the
scale origin signal detection method. When a hardware limit switch is detected during machine home position return, the
error "Hardware stroke limit (+)" (error code: 1904H, 1905H) or "Hardware stroke limit (-)" (error code: 1906H, 1907H) will
occur.
• Position the near-point dog forward to overlaps with the hardware limit switch in direction of home position return. When the
near-point dog is in the opposite direction against of home position return from the machine home position return start
position, the error "Hardware stroke limit (+)" (error code: 1904H, 1905H) or "Hardware stroke limit (-)" (error code: 1906H,
1907H) will occur.
Home position
Machine home position return
Hardware limit switch
M
Near-point dog
Hardware limit switch
2 HOME POSITION RETURN CONTROL
2.2 Machine Home Position Return
2
43