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6. PARAMETERS 6.1.8 Electronic gear
Parameter
No. Symbol Name
Initial
value Unit Setting range
PA06 *CMX Electronic gear numerator 1 0 to 65535
PA07 *CDV Electronic gear denominator 1 1 to 65535
CAUTION False setting will result in unexpected fast r otation, causing injury.
POINT
This parameter is made valid when power is switched off, then on af ter
setting.
The range of the electronic gear setting is CMX
CDV
1
10 2000. If you set any
value outside this range, a parameter error (A37) occurs.
Setting "0" in parameter No.PA06 automatically sets the encoder resoluti on
pulse.
(1) Concept of electronic gear
Use the electronic gear (parameters No.PA06, PA07) to make adjustment so that the servo amplifier setting
matches the moving distance of the machine. Also, b y changing the electronic gear value, the machine can
be moved at any multiplication ratio to the m oving distance on the servo amplifier.
CMX
CDV
Parameters No.PA06
Parameters No.PA07
Encoder feedback pulses
CMX
CDV
Deviation
counter
Motor
Encoder
Moving
distance
+
-
Electronic gear
Parameters No.PA06,PA07
The following examples are used to explain ho w to calculate the electronic gear value.
POINT
The following specification symbols are needed for electronic ge ar
calculation.
Pb : Ball screw lead [mm]
n : Reduction ratio
Pt : Servo motor resolution [pulse/rev]
S : Travel per servo motor revolution [mm/rev]
(a) Ball screw setting example
Machine specifications
Ball screw lead: Pb 10 [mm]
Reduction ratio: n 1/2
Servo motor resolution: Pt 262144 [pulse/rev] Servo motor 262144[pulse/rev]
n
NM
NL
Pb=10[mm]
n=NL/NM=1/2
CMX
CDV S
pt
5000
262144
625
32768
pt
n 1000
pb
262144
1/2 10 1000
Hence, set 32768 to CMX and 625 to CDV.