YASKAWA SGD7S Product Manual page 342

8.12 Additional Adjustment Functions
8.12.7 Backlash Compensation
 Operation When the Servo Is ON
The backlash compensation value (Pn231) is added in the backlash compensation direction
when the servo is ON (i.e.,while power is supplied to the motor) and a reference is input in the
same direction as the backlash compensation direction (Pn230.0 = n.X).
When there is a reference input in the direction opposite to the backlash compensation direc-
tion, the backlash compensation value is not added (i.e., backlash compensation is not per-
formed).
The relationship between APOS and the motor shaft position is as follows:
• If a reference is input in the compensation direction: APOS = Motor shaft position − Pn231
• If a reference is input in the direction opposite to the compensation direction: APOS = Motor
shaft position
The following figure shows driving the Servomotor in the forward direction from target position
TPOS0 to TPOS1 and then to TPOS2, and then returning from TPOS2 to TPOS1 and then to
TPOS0.
Backlash compensation is applied when moving from TPOS0 to TPOS1, but not when moving
from TPOS2 to TPOS1.
Driving in the Forward
Reference Direction
Driving in the Reverse
Reference Direction
8-76
Servo ON
Target position
TPOS0
Reference travel
distance 1
POS
APOS
Machine shaft
Pn231
Reference travel
Motor shaft
Machine shaft
Motor shaft
Backlash compensation value (Pn231)
Reference travel
distance 1
POS
APOS
Machine shaft
Reference travel
distance 1
Motor shaft
Machine shaft
Motor shaft
Target position Target position
TPOS1 TPOS2
Reference travel
distance 2
Reference travel
distance 1 distance 2
Reference travel
distance 2
Reference travel
distance 2
Backlash compensation value (Pn231)
Forward reference
direction
Pn231