Extra Functions
Section 3-7
54
3-7
Extra Functions
3-7-1
Hysteresis
An encoder can come to rest at a particular position and then “oscillate” around
this position. This state means that the Counter Value fluctuates around a partic-
ular value. If, for example, a Range Limit is in this area of fluctuation, the corre-
sponding Range would become active and inactive in the rhythm of these
fluctuations. To prevent outputs from being switched ON and OFF by very small
fluctuations, the Counter Unit offers the Hysteresis Function that can be config-
ured for every Counter separately. You can assign Hysteresis in a range from 1 to
255 counts (= 0001
H
– 00FF
H
) from which the Counter treats the fluctuation in the
Counter Input Signal as a real change and outputs can be controlled accordingly.
Configuring Hysteresis
Note
1. The Hysteresis can only be applied to Units in Range Mode. If the Unit is in
Comparison Mode you are able to configure Hysteresis yourself using Compar-
ison Values.
2. Do not set the origin (i.e., a present value of 0) within the Hysteresis-Area.
3. If the Counter is Preset, turn OFF the Hysteresis. If the Counter is Preset in the
Hysteresis-Area, the Outputs will not be controlled correctly.
Down-Counting
UP-Counting
Hysteresis
Hysteresis
Range Active
Range Inactive
Lower
Range Limit
Upper
Range Limit
H
H
CNT3:
CNT4:
m+65
m+85
Hysteresis:
0000 = No Hysteresis
Set Hysteresis in number of counts between 0001-0255 (= 0001
H
– 00FF
H
)
CNT1:
CNT2:
m+25
m+45
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
