Hardware Stroke Limit Function; Control Details - Mitsubishi Electric MELSEC Q Series User Manual

10 FUNCTION DETAILS

10.3 Hardware Stroke Limit Function

When the hardware stroke limit is required to be wired, ensure to wire it in the negative logic
using B-contact. If it is set in positive logic using A-contact, the hardware stroke limit may not be
detected even if the signal wires are disconnected.

10.3.1 Control details

This function is used to make stop (sudden stop) the control by the input of a signal
from the limit switch, by setting the limit switches at the upper/lower limit of the
physical moveable range.
Damage to the machine can be prevented by stopping the control before the
upper/lower limit of the physical moveable range is reached.
Use "external input signal of servo amplifier" in the hardware stroke limit.
The operation for the hardware stroke limit function is shown below.
Lower limit
Control moveable range
Mechanical stopper
Movement
direction
Sudden stop at lower
limit switch detection
Lower limit
switch
POINT
The deceleration stop is executed by setting the sudden stop deceleration time.
Keep enough distance between the limit switch and the mechanical stopper in
consideration of a distance necessary for the stop.
CAUTION
Upper limit
Mechanical stopper
Movement
Start
direction
Sudden stop at upper
limit switch detection
Upper limit
switch
10 - 7
Servo amplifier
Servo amplifier input
MELSEC-Q
QD74MH