
B--63003EN--1/02
9. SPINDLE SPEED FUNCTION
778
4971 Servo loop gain multiplier of the spindle for gear 1
4972 Servo loop gain multiplier of the spindle for gear 2
4973 Servo loop gain multiplier of the spindle for gear 3
4974 Servo loop gain multiplier of the spindle for gear 4
[Data type] Word
Set the servo loop gain multipliers of the spindle for gears 1 to 4.
The multipliers are used to convert the amount of the position deviation
to the voltage used in the velocity command. Assign the data obtained
from the following equation to the parameters.
Loop gain multiplier = 2048000 × E × A/L
where;
E: Voltage required to rotatethe spindle motor at 1000 rpm in the velocity
command
L: Rotation angle of the spindle per one motor rotation (normally 360)
A: Unit used for the detection (degree)
Example) Let E be 2.2 V, L be 360 degrees, and A be 0.088
degrees/pulse.
Loop gain multiplier = 2048000 × 2.2 × 0.088/360 =
1101
NOTE
1 When the voltage specified for the spindle motor is 10 V at
a spindle speed of 4500 rpm, E is regarded as 2.2 V.
2 The above parameters No. 4970 to No. 4974 are for analog
spindle.