YASKAWA Sigma-7 SGD7S Series

For example, consider a machine that moves the turntable shown in the following dia-
gram in only one direction.
Turntable
Gear
n:m
Servomotor
Fig. 171: Turntable Application Example
Because the turntable moves in only one direction, the upper limit to the number of rota-
tions that can be counted by an absolute encoder will eventually be exceeded.
The multiturn limit is used in cases like this to prevent fractions from being produced by
the integral ratio of the number of Servomotor rotations and the number of turntable rota-
tions.
For a machine with a ratio of n:m between the number of Servomotor rotations and the
number of turntable rotations, as shown above, the value of m minus 1 will be the setting
for the multiturn limit setting (Pn205).
Multiturn limit (Pn205) = m - 1
If m = 100 and n = 3 (i.e., the turntable rotates three times for each 100 Servomotor rota-
tions), the relationship between the number of Servomotor rotations and the number of
turntable rotations would be as shown below.
Set Pn205 to 99.
Pn205 = 100 - 1 = 99
0
1
2
3
4
5
6
7
8
9
100 200 300 0
100
50
Number of table rotations
Multiturn data
Number of table rotations
Multiturn data
Setting of Pn205 = 99
Number of rotations
Fig. 172: Relationship Between the Number of Turntable Revolutions and the Number of
Motor Revolutions
Multiturn Limit
Setting
Range
Setting Unit Default Set-
ting
When Ena-
bled
Classifica-
tion
Pn205 0 to 65,535 1 Rev 65,535 After restart Setup
(applies to Speed Control, Position Control and Torque Control)
This parameter is enabled when you use an absolute encoder.
Sigma-7 Series SERVOPACKs
Application Functions
Absolute Encoders > Multiturn Limit Setting
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