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5. PARAMETERS
5.2 Detailed Description
5.2.1 Electronic gear
POINT
• The guideline of the electronic gear setting range is 1
50 < CMX
CDV 50. If the
set value is outside this range, noise may be generated during
acceleration/deceleration or operation may not be performed at the preset
speed and/or acceleration/deceleration time constants.
(1) Concept of electronic gear
The machine can be moved at any multiplication factor to input pulses.
CDV
CMX = 4 No. Parameter 3 No. Parameter
Electronic gear
Parameters No. 3, 4
Encoder feedback pulse
CMX
CDV Deviation
counter
Motor
Encoder
Input pulse train
+
−
The following setting examples are used to explain how to calculate the electronic gear:
(a) For motion in increments of 10µm per pulse
Machine specifications
Ballscrew lead Pb =10 [mm]
Reduction ratio: n = 1/2
Servo motor resolution: Pt = 8192 [pulses/rev]
Servo motor
8192 [pulse/rev]
n
NM
NL
Pb=10[mm]
n=NL/NM
=1/2
CDV
CMX = ∆lο x S
Pt
∆= ∆lο x =PbnPt
⋅ 10×10-3 x 10218192
⋅ =1000
16384 = 125
2048
Hence, set 2048 to CMX and 125 to CDV.
(b) Conveyor setting example
For rotation in increments of 0.01° per pulse
Machine specifications
Table resolution: 36000 pulses/rev
Reduction ratio: n = 4/64
Servo motor resolution: Pt = 8192 [pulses/rev]
Table
Timing belt : 4/64
Servo motor
8192 [pulse/rev]
CDV
CMX = S
Pt
∆ = 64436000
Pt
× = 36000
131072 = 1125
4096
Reduce CDV to 32767 or less and round off the result to the units.
Hence, set 4096 to CMX and 1125 to CDV.