Gap Sensor-Related Parameters - YASKAWA SGD7S series Product Manual

4.4.4

Gap Sensor-Related Parameters

The analog voltage that is output by the gap sensor amplifier is converted to a digital signal in
the SERVOPACK. The digital value that results from converting an analog signal is called the
AD value. The settings of the following two parameters are used to convert the AD values to
feedback pulse units.
You can use the Motion Monitor Tab Page on the SigmaWin+ or the Un116 utility function of
the Digital Operator to check gap AD values.
AD Input Gain
Pn6F6 Setting Range
0 to 1,073,741,824 0.1 pulse/AD value
AD Zero Correction
Pn6F8 Setting Range
-4,095 to 4,095
Setting the AD Input Gain
Set Pn6F6 (AD Input Gain) to the number of pulses from the motor encoder that corresponds
to the AD value from the gap sensor. Use the following formula.
Pn6F6 [0.1 pulse/AD value] =
If the AD value of the gap sensor changes from 423 to 623 after you change the gap from 1.0
Example
mm to 1.5 mm in a machine with a 24-bit encoder and a ball screw pitch of 8 mm, use the
above formula to calculate Pn6F6 as follows:
Refer to the following section for details on conversion of gap sensor AD values.
Setting the AD Zero Correction
Set Pn6F8 (AD Zero Correction) to the gap AD value for the gap 0 mm position.
In the case shown in the following diagram, if you extrapolate the gap AD value, the AD value
Example
for gap 0 mm will be 23, so set Pn6F8 to 23.
Setting Unit
Setting Unit
AD Value
Number of encoder pulses [pulses/revolutions] ×
Gap AD value conversion amount after analog-to-digital conversion [AD value]
Pn6F6 [0.1 pulse/AD value] =
Setting the AD Zero Correction on page 4-9
Gap
[AD value]
623
423
23

4.4.4 Gap Sensor-Related Parameters

Position
Default Setting
0
Default Setting
0
Gap conversion amount [mm]
Ball screw pitch [mm/Rev]
1.5 – 1.0
2 24 ×
8
× 10 = 52428.8
623 – 423
1.0 1.5
4.4 Parameter Setting Procedure
Classifica-
When Enabled
tion
Immediately Setup
Position
Classifica-
When Enabled
tion
Immediately Setup
× 10
52429
Gap
[mm]
4
4-9