Mitsubishi Electric QD75P1N User Manual page 847

APPENDICES
EXTERNAL REGENERATIVE BRAKE
RESISTOR
This is also called the regenerative brake.
When a machine is moved with a motor, power
is normally supplied to the motor from an
amplifier. However, the rotation energy in the
motor and machine counterflows (regenerates)
to the amplifier when the motor is decelerating
or when driving a descending load.
The external regenerative resistor consumes
this regeneration energy with resistance,
obtains the regenerative brake torque, and
enables the full capacity of the regeneration
system during stopping.
It is used when carrying out highly repetitive
acceleration/deceleration.
F
In the QD75, F is a status where the module
itself has a fault.
[HOLD]
FAST OPR
The axis returns to the machine OP at the
OPR speed without detecting the near-point
dog.
(This is not validated unless a machine OPR
has been carried out first.)
OPR speed
Dog switch
FEED PULSE
This is a pulse issued from the positioning
module to a servomotor or stepping motor.
Also called a command pulse.
OP
Appendix - 131
FEED SCREW
This is the basic screw in mechanisms that
position using screw rotation. Ball screws are
often used to reduce backlash and dimension
error.
1 rotation
by the motor
Lead (feedrate per screw rotation)
FEEDBACK PULSE
This is a method of using a returning pulse
train to confirm whether the machine faithfully
operated according to the commands issued in
automatic control. If the machine did not
faithfully operate according to the commands,
a correction command is issued. For example,
if a command is issued for 10,000 pulses, and
a feedback pulse of 10,000 pulses is returned,
then the balance becomes 0 and it can be
judged that the command was faithfully
followed.
Refer to the term "DEVIATION COUNTER".
FIXED-FEED
This is the feeding of a set dimension for
cutting sheet and bar workpieces into the
designated dimensions. Incremental system
positioning is often used. The current value is
not incremented, even when the feed
operation is repeated.
FLASH MEMORY
This battery-less memory can be used to store
parameters and positioning data for backup.
Because it is battery-less, battery maintenance
is not required
FLAT TYPE MOTOR (PANCAKE MOTOR)
About 100mm shorter in axial dimension than
the standard motor. Used when the
servomotor is installed in a small space.
MELSEC-Q
Positioning
feed screw