Multiturn Limit Setting - YASKAWA SGMJV User Manual

5 Operation

5.9.7 Multiturn Limit Setting

5.9.7 Multiturn Limit Setting

The multiturn limit setting is used in position control applications for a turntable or other rotating device. For
example, consider a machine that moves the turntable in the following diagram in only one direction.
Because the turntable moves in only one direction, the upper limit for revolutions that can be counted by an
absolute encoder will eventually be exceeded. The multiturn limit setting is used in cases like this to prevent
fractions from being produced by the integral ratio of the motor revolutions and turntable revolutions.
For a machine with a gear ratio of m:n, as shown above, the lowest common multiple (LCM) of m:n minus 1
will be the setting for the multiturn limit setting (Pn205).
Multiturn limit setting (Pn205) = LCM-1
The case in which the relationship between the turntable revolutions and motor revolutions is m = 3 and n =
100 is shown in the following graph.
The lowest common multiple of m and n is 300.
Pn205 = 300 - 1 = 299
Pn205
Note: This parameter is valid when the absolute encoder is used.
The range of the data will vary when this parameter is set to anything other than the factory setting.
1. When the motor rotates in the reverse direction with the rotational data at 0, the rotational data will change
to the setting of Pn205.
2. When the motor rotates in the forward direction with the rotational data at the Pn205 setting, the rotational
data will change to 0.
5-74
Turntable
5
revolutions
(rotational data)
4
3
2
1
0
300
Multiturn Limit Setting
Setting Range Setting Unit
0 to 65535
Turntable
Gear
Motor
600 900
Motor revolutions
Speed
Factory Setting
1 Rev 65535
1200 1500
Position
Torque
When Enabled
After restart
Classification
Setup