Yaskawa MP920 User's Manual Design - Manual (Page 143)

4.3 Position Control
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Note: The number of digits below the decimal point is specified in motion
fixed parameter No. 18 (Number of Digits Below Decimal Point).
„ Electronic Gear
In contrast to the reference unit input to the Module, the mechanical travel unit is called the
“output unit.”
The electronic gear converts position or speed units from reference units (millimeters,
degrees, or inches) to output units (millimeters, degrees, or inches).
When the axis at the motor has rotated m times and the mechanical configuration allows the
axis at the load to rotate n times, this electronic gear function can be used to make the refer-
ence unit equal to the output unit.
The electronic gear function is set in the motion setting parameters shown in Table 4.10.
When the unit selected is the pulse and motion commands (OW††20) are not used, the
electronic gear function is disabled.
Table 4.9 Minimum Reference Unit (1 Reference Unit)
Number of
Digits Below
Decimal Point
Motion Fixed Parameter No. 17
Bits 0 to 3 of Motion Controller Function Selection Flags
Pulse (= 0) mm (= 1) deg (= 2) inch (= 3)
0 1 pulse 1 mm 1 deg 1 inch
1 1 pulse 0.1 mm 0.1 deg 0.1 inch
2 1 pulse 0.01 mm 0.01 deg 0.01 inch
3 1 pulse 0.001 mm 0.001 deg 0.001 inch
4 1 pulse 0.0001 mm 0.0001 deg 0.0001 inch
5 1 pulse 0.00001 mm 0.00001 deg 0.00001 inch
Table 4.10 Electronic Gear Parameters
Motion Fixed Parameter Name and Meaning
No. 17
Bit 4 of Motion Controller
Function Selection Flags Electronic gear enabled selection (0: Disabled, 1: Enabled)
• Disabled when the unit selected is the pulse. Set Disabled (= 0).
No. 19
Distance Travelled per
Machine Rotation Travel distance per machine rotation
• This parameter setting is invalid when Disabled (= 0) is set for the
electronic gear enabled selection.
No. 21
Servomotor Gear Ratio Motor side gear ratio
• This parameter setting is invalid when Disabled (= 0) is set for the
electronic gear enabled selection.
No. 22
Machine Gear Ratio Machine side gear ratio
• This parameter setting is invalid when Disabled (= 0) is set for the
electronic gear enabled selection.