YASKAWA SGD7S-1R9D Product Manual page 332

8.12 Additional Adjustment Functions
8.12.7 Backlash Compensation
 Operation When the Servo Is OFF
Backlash compensation is not applied when the servo is OFF (i.e., when power is not supplied
to motor). Therefore, the reference position (position demand value (6062 hex)) is moved by
only the backlash compensation value.
The relationship between position actual value (6064 hex) and the motor shaft position is as fol-
lows:
• When servo is OFF: Position actual value (6064 hex) = Servomotor shaft position
The following figure shows what happens when the servo is turned OFF after driving the Servo-
motor in the forward direction from target position Target Position 0 to Target Position 1. Back-
lash compensation is not applied when the servo is OFF. (The SERVOPACK manages the
position data so that position actual value (6064 hex) and position demand value (6062 hex) are
the same.)
 Operation When There Is Overtravel
When there is overtravel (i.e., when driving is prohibited due to an overtravel signal or software
limit), the operation is the same as for when the servo is OFF (
OFF on page 8-74), i.e., backlash compensation is not applied.
 Operation When Control Is Changed
Backlash compensation is performed only for position control.
Backlash compensation is not applied when position control is changed to any other control
method.
Backlash compensation is applied in the same way as when the servo is ON (
When the Servo Is ON on page 8-73) if any other control method is changed to position con-
trol.
Related Monitoring
You can monitor the following values on the operation monitor of the SigmaWin+.
Input Reference Pulse Speed
Position Deviation
Input Reference Pulse
Counter
Feedback Pulse Counter
Fully-Closed Feedback Pulse
Counter
Feedback Pulse Counter
8-74
Target position
Target Position 0
Position demand
value (6062 hex)
Position actual
value (6064 hex)
Machine shaft
Pn231
Motor shaft
Machine shaft
Motor shaft
Backlash compensation value (Pn231)
Displayed Value
Reference units
Reference units
Encoder pulses
External encoder
Reference units
Servo OFF
Target position
Target Position 1
Reference travel distance
Reference travel distance
Unit
Displays the input reference pulse speed before backlash
-1
min
compensation.
Displays the position deviation for the position reference
after backlash compensation.
Displays the input reference pulse counter before back-
lash compensation.
Displays the number of pulses from the actually driven
motor encoder.
Displays the number of pulses of the actually driven exter-
resolution nal encoder.
Displays the number of pulses from the actually driven
encoder in reference units.
Forward
reference
direction
Status with no backlash
compensation:
Position demand value (6062 hex)
= Position actual value (6064 hex)

Operation When the Servo Is

Operation
Specification