Lenze I/O system 1000 System Manual - Manual (Page 187)

Product description
I/O compound modules − counter
Two counters 32 bits, 24 V DC − EPM−S601
3
l
187 EDSIO1000 EN 7.0
Hysteresis
The hysteresis for instance serves to avoid frequent switching operations of the output
and triggering of the alarm when the count value is within the range of the comparison
value. For the hysteresis you can select a range between 0 and 255. With the settings 0 and
1 the hysteresis is switched off. The hysteresis has an effect on the zero crossing,
overflow/underflow, and on the comparison value.
An active hysteresis remains active after the change. The new hysteresis range becomes
active at the next hysteresis event.
In the following illustrations the response of the output at hysteresis 0 and hysteresis 3 for
the corresponding conditions is represented:
A) Function mode in the case of count value
³ comparison value
When the comparison condition is met, hysteresis becomes active. When hysteresis is
active, the comparison result remains unchanged until the count value exits the hysteresis
range set. After the hysteresis range is exited, hysteresis is only activated again when the
comparison conditions are met.
8
7
6
5
4
3
2
1
0
Comparison
value
Hysteresis
Comparison bit:
Hysteresis = 0
Hysteresis = 3
Count value
1
2
3 4 5 6
7
SLIO41
 Count value ³ comparison value ®Comparison bit is set and hysteresis is activated
‚ Exiting of the hysteresis range ®Comparison bit is reset
ƒ Count value ³ comparison value ®Comparison bit is set and hysteresis is activated
„ Exiting of the hysteresis range, comparison bit remains set, since count value ³ comparison
value
Count value < comparison value and hysteresis active ® Comparison bit is reset
† Count value ³ comparison value ®Comparison bit is not set since hysteresis is activated
‡ Exiting of the hysteresis range, comparison bit is set, since count value ³ comparison value