Siemens SIMATIC ET 200SP - Page 151

Using the SSI_Absolute_Encoder technology object
4.4 Configuring SSI_Absolute_Encoder
Counting, measurement and position detection
150 Function Manual, 12/2017, A5E32009889-AG
Count direction
You use this parameter to specify the direction of position value change for which the
selected function is valid.
You can select from the following options:
Direction of position value
change
Meaning
In both directions
(default)
The comparison and switching of the respective digital output is
carried out regardless of whether the position value increases of
decreases.
Up The comparison and switching of the respective digital output only
takes place when the position value increases.
Down
The comparison and switching of the respective digital output only
takes place when the position value decreases.
The parameter can be configured for the following functions:
● At comparison value for a pulse duration
● After set command from CPU until comparison value
Pulse duration
By configuring the pulse duration for the function "At comparison value for a pulse duration",
you specify the number of milliseconds for which the respective digital output is active.
A value from 0.1 to 6553.5 ms is permissible.
The default setting is "500.0", which is equivalent to a pulse duration of 0.5 s.
Hysteresis (in increments)
By configuring the hysteresis (Page 64), you can define a range around the comparison
values. Within the hysteresis range, the digital outputs cannot switch again until the position
value has left this range once.
If you enter "0", the hysteresis is turned off. You can enter a value between 0and 255. The
default setting is "0".
Note
You configure the
hysteresis under "Behavior of DQ0" for both digital outputs together. The
hysteresis is also displayed under "Behavior of DQ1".
Note
The hysteresis is only available in operating mode "Use position value (SSI absolute value)
as reference".