Siemens SIPART PS2 6DR52xx - Manual (Page 114)

Operation
114
SIPART PS2 Manual
A5E00074631--06
Slipstick effect
This parameter is used to activate the function for the detection of a
slipstick effect. The device tries to detect sudden changes of the valve
position that indicate excess slipstick. If the device detects a slipstick,
the filtered step is saved as slipstick value. When the valve moves
normally again (without detection of a slipstick), the slipstick value is
reduced slowly.
Note that to avoid misinterpretations, for actuators with actuating times
below 1 s, the positioner cannot distinguish reliably between a normal
movement and a sudden change.
Limit for the slipstick detection
Sets the limit for a step caused by a slipstick effect. The limit can be
set within the range of 0.0 to 100.0%. Factory setting for the limit is 1.0.
Factor 1
Input of the factor for the threshold 1 error message. This factor refers
to the limit for the slipstick detection. Factory setting for factor 1 is 2.0.
That means, for d1.LIMIT = 1.0 and factor 1 = 2.0, the first slipstick
error message is triggered when the current slipstick value has reached
2.0.
Factor 2
Input of the factor for the threshold 2 error message. This factor refers
to the limit for the slipstick detection. Factory setting for factor 2 is 5.0.
That means, for d1.LIMIT = 1.0 and factor 2 = 5.0, the second slipstick
error message is triggered when the current slipstick value has reached
5.0.
Factor 3
Input of the factor for the threshold 3 error message. This factor refers
to the limit for the slipstick detection. Factory setting for factor 3 is 10.0.
That means, for d1.LIMIT = 1.0 and factor 3 = 10.0, the third slipstick
error message is triggered when the current slipstick value has reached
10.0.
d. STIC
d1.LIMIT
d2.FACT1
d3.FACT2
d4.FACT3