
16
16.1 Initial Setting Servo Parameters (αi/α)
824
F⋅FG numerator
F⋅FG denominator
=
36000
1,000,000
=
36
1000
Setting for use of a separate detector (full–closed)
Number of position pulses corresponding
to a predetermined amount of travel
F⋅FG numerator (v 32767)
(as irreducible fraction)
Number of position pulses corresponding
to a predetermined amount of travel from
a separate detector
F⋅FG denominator (v 32767)
=
[Example]
To detect a distance of 1–µm using a 0.5–µm scale, set the following:
Numerator of F⋅FG
Denominator of F⋅FG
=
L/1
L/0.5
=
1
2
<<Examples of calculation>>
1/1000 mm 1/10000 mm
One revolution 8mm
of motor 10mm
12mm
n=1/m=125
n=1/m=100
n=3/m=250
n=2/m=25
n=1/m=10
n=3/m=25
(6) Direction of travel
2022
Rotational direction of motor
PRM
111 : Normal (clockwise) –111 : Reverse (counterclockwise)
(7) Number of velocity pulses and position pulses
Closed loop
Parameter
number
Semi–
closed
loop
Parallel
type
Serial
linear
scale
Serial
rotary
scale
Increment
system
¯
1/1000
1/10000
1/1000
1/10000
1/1000
1/10000
1/1000
1/10000
Bit 0 of initial
setting bit
PRM
2000#0
#0=0 #0=0 #0=0 #0=0
Number of
velocity pulses
PRM 2023 8192 8192 8192 8192
Number of
position pulses
PRM 2024 12500 Ns (*) Ns (*) Np (*)
Ns: Number of position pulses from the separate detector counted
when the motor makes one revolution
(Value after multiplication by a factor of 4 not considering the
flexible feed gear)
Np: 12500 (Deceleration rate or acceleration rate from motor to table)
Example: When the motor makes 10 revolutions for one table
revolution, Np = 12500/10 = 1250
2023
Number of velocity pulses
PRM
2024
Number of position pulses
PRM
With the CNC, there is no dependency relationship between the
increment system and the initialization bit (PRM2000#0). However, the
conventional setting is also possible. See the note below.