Spirax Sarco SP8-10, Installation And Maintenance Instructions Manual

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IM-P707-01 CTLS Issue 1
64
SP8-10 Smart positioner
5.1.23 Menu: Controller
(continued)
Menu/parameter Value range Description
Y-Offset Down 1 to 100.0 %
Use this parameter to adjust the Y offset for the down
positioning direction (towards 0 %).
The ‘offset for the set point signal’ linearizes the
behavior of the I/P module used and enables rapid
compensation even in the case of small control
deviations. The value is limited at the lower end by a
minimum value (neutral zone).
The offset significantly affects the control speed for
control deviations of less than 5 %.
To compensate for existing dissymmetries in the
controlled system, the offset should be configured
separately for both positioning directions (up/down).
For most actuators, satisfactory control behavior is
achieved with offset values between 40 ... 80 %.
If, in the event of set point changes, the control
behavior demonstrates an overshoot of less than 2%,
both offset values should be decreased.
Both offset values should be increased when the
actuator stops outside the dead band.
Note:
In the case of most actuators, all control parameters can be optimized by using Auto Adjust. The
parameters should only be changed if Auto Adjust cannot be executed or does not result in satisfactory
control behavior.