Mitsubishi QD75M1, User Manual

Page: 845 / 882

Appendix - 92
MELSEC-Q
APPENDICES
STROKE LIMIT
This is the range in which a positioning
operation is possible, or the range in which the
machine can be moved without damage
occurring.
(Movement outside this range is possible in
the manual operation.) For operations using a
worm gear, the stroke limit is determined by
the length of the screw. For operations using a
fixed-feed, it is determined by the max.
dimension to be cut.
The upper and lower limits are set in the
parameters, but a separate limit switch should
be established and an emergency stop circuit
outside the PLC should be created. Refer to
the term "LIMIT SWITCH".
Lower limit
0
Upper limit
Limit switch
for emergency
stop
Positioning possible in a 3m (9.84feet) range
3m (9.84feet)
SUDDEN STOP
A stop carried out in a shorter time than the
deceleration time designated in the
parameters.
Full speed
Sudden stop
Time
Deceleration time
TEACHING
When the positioning address is uncertain, or
gauging is required, this function is used by
the user to search for and teach the position to
the machine.
For example, complex addresses such as
drawings can be taught by tracing a model,
and the positioning operation can be
reproduced.
TORQUE CONTROL
In this function, a limit is established for the
resistance torque applied to the motor used for
positioning. The power is turned OFF if torque
exceeding that value is applied to the motor.
When excessive torque is applied to a motor, it
causes the current to suddenly increase. Motor
burning and other stress on the motor occurs,
and the life of the motor is shortened.
This function utilizes the sudden increase in
the torque when the machine OPR to issue a
command to stop the motor.
TORQUE LOOP MODE
Also called the current loop mode.
Refer to "POSITIONING LOOP MODE".
TORQUE RIPPLE
Torque width variations, deviations in the
torque.
TRACKING FUNCTION
In this function, positioning is carried out at a
speed relative to a moving target object by
inputting the movement amount from an
external encoder and adding it to the servo
command value.