Monitoring The Stiction (Slipstick) "D._Stic - Siemens 6DR50 Series Operating Instructions Manual

C4.FACT3 - Factor 3
Adjustment range:
Purpose:
Factory setting:
9.4.3.4

Monitoring the stiction (slipstick) "d._STIC"

d. STIC - Monitoring the stiction (slipstick)
Requirement:
Possible settings:
Purpose:
Factory setting:
Note
Incorrect interpretation in case of travel times below one second
If the travel times are less than one second, the positioner does not accurately differentiate
between a normal movement of the actuator and a sudden change. Therefore, increase the
travel time if required.
SIPART PS2 with and without HART
Operating Instructions, 09/2014, A5E00074631-12
0.1 ... 100.0
Use this sub-parameter to set the factor for the formation of limit
threshold 3. Set the factor in a range from "0.1" to "100.0". The
limit threshold is the product of "C1.LIMIT" and "C4.FACT3" .
The threshold 3 error message is displayed when the limit thresh-
old 3 is exceeded. The procedure to activate and display this error
message is described in the "XDIAG" parameter.
2.0
The "'52.XDIAG' Activating for extended diagnostics (Page 174)"
parameter is set to "On".
• OFF
• On
Use this parameter to continuously monitor the current stiction
(slipstick) of the control valve. If the parameter is activated, the
positioner detects the slipstick that may occur. Sudden changes in
the valve position, so-called slip jumps, indicate excessive stiction.
Where slip jumps are detected, the filtered step height is stored as
a slipstick value. If slip jumps no longer exist, the stiction (slipstick)
is reduced slowly.
The current value is displayed in "Diagnostics parameter '17.STIC'
Stiction (slipstick) (Page 214)". The positioner triggers an error
message if the current value exceeds a limit threshold.
Sub-parameters are described below.
OFF
Parameterizing/addressing
9.4 Description of parameters
185