Mitsubishi Melsec-A Series User Manual page 11

General design of positioning system
Pulse generator
(PGI
Servo motor
W
P
A : Position detection increment (mm/p)
Vs
:
Command pulse frequency (p/s)
n : Number of pulse generator slits (slitshev)
L
:
Feed screw lead (mm/rev)
R
: Reduction ratio
V
: Moving part speed (mm/s)
N
: Motor speed (rpm)
K
: Position loop gain
(sec-'
1
E
:
Deviation counter pulse value
PO : Zero point (pulse)
P : Address (pulse)
(1
)
Position detection increment
(2) Command pulse frequency
(3)
Deviation counter pulse value
E
=
-
(pulse)
VS
K
Expression (1) indicates the travel
per pulse,
i.e. the number
of
output pulses x A. Using expression
(2).
calculate the command
pulse frequency from the work speed and position detection incre-
ment. Expression
(3)
indicates the relation between the command
pulse frequency and deviation counter pulse value.
Any of the four positioning units, (mm), (inch), (degree), and
(PULSE), may be selected individually for the X and Y axes.