Mitsubishi A1SD75M1, User Manual

Page: 705 / 746

Appendix - 37
MELSEC-A
APPENDICES
ENCODER
This device turns the input data into a binary
code of 1 (ON) and 0 (OFF). A type of pulse
generator.
A
B
Z
Ball bearing
For the main
signal For the zero
point signal
Input axis
Code disk
Photoreceptor
(phototransistor)
Index
scale
Light source
(light-emitting diode)
Rotary encoder
a
a
b
z
b
Light source
(LED)
Collimator lens
Main scale
Photoreceptor
(photodiode)
Reference
zero point Index
scale
Linear encoder
ERROR CORRECTION
If a dimension error occurs in the machine,
and that error is actually smaller or larger than
1m in spite of a 1m command being issued
from the AD75, that error amount will be
compensated. For example, when the error is
actually smaller than 1m, the remaining
distance to 1m is fed, and the correct 1m of
positioning is carried out.
ERROR RESET
This resets error of axis. Note that if the cause
of the error is not eliminated at that time, the
error will occur again.
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 AD75, this is a status where there is a
fault in the module itself.
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-DIMENSION FEED
This is the feeding of a set dimension for
cutting sheet and bar workpieces into the
designated dimensions. Increment 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.