6 SERVO MOTOR DRIVING
6.1 Homing mode (hm)
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6
Method -7 and -39 (count type front end reference home position return)
• This home position return type depends on the timing of reading DOG (Proximity dog) that has detected the
front end of the proximity dog. Therefore, when the creep speed is set to 100 r/min and a home position
return is performed, the home position has an error of ± (Encoder resolution) × 100/65536 [pulse]. The
faster home position return speed sets a larger error in the home position.
The following figure shows the operation of Homing method -7. The operation direction of Homing method -39 is opposite to
that of Homing method -7.
*1 After the front end of the proximity dog is detected, if the distance after proximity dog is traveled without reaching the creep speed, [AL.
90] occurs. Set both the travel distance after proximity dog and home position shift distance enough for deceleration from the home
position return speed to the creep speed.
*2 The home position shift distance can be changed with [Pr. PT07] and [Pr. PT69].
*3 The travel distance after proximity dog can be changed with [Pr. PT09] and [Pr. PT71].
• When a home position return is started from the proximity dog
• When the movement is returned at the stroke end
*1 This is not available with the software limit.
Statusword bit 10
Target reached
Statusword bit 12
Homing attained
0 r/min
Controlword bit 4
Homing operation start
ON
OFF
ON
OFF
ON
OFF
ON
OFF
*1
Travel distance after proximity dog
*3
+
Home position shift distance
*2
Deceleration time
constant
Acceleration time
constant
Home position return speed
Creep speed
Forward
rotation
Servo motor speed
10 ms or shorter
Reverse
rotation
Home position return position data
Proximity dog
DOG (Proximity dog)
0 r/min
Home position return direction
Proximity dog
Servo motor speed
Reverse
rotation
Home position return start position
Moves back automatically before the proximity dog,
then performs home position return from this position.
0 r/min
Home position return direction
Stroke end
*1
Proximity dog
Home position return start position
Forward
rotation
Servo motor speed
Reverse
rotation
Performs home position return from this position.
