Festo CMSX-C-U-F1 Series Manual page 39

CMSX-...-C-U-F1-...
Operation
Briefly press Add
Briefly press Sub
Briefly press Set
Press and hold Set
Tab. 19 Operation in the Parameter menu (3)
Dead zone (DEADBAND)
The parameter DEADBAND (dead zone) establishes the lower and upper limit of the zone within which a
change in the controlled variable has no influence on the setpoint specification. A change in the set­
point specification takes place only if the dead zone is exceeded. The setpoint specification is only
constant if the deviation lies within half the dead zone (b > deviation > ­b).
4
1
1
Setpoint specification (controller output signal)
2
Deviation (controller input signal)
Fig. 28 Dead zone
The size of the dead zone influences the positioning accuracy and sensitivity with which the positioner
reacts to a deviation.
A dead zone that is too small results in vibration tendencies around the setpoint position up to perman­
ent oscillations (instability). Through this, the fast-switching valves in the positioner and the drive are
subject to unnecessary loads. A dead zone that is too large results in low positioning accuracy.
Festo – CMSX-...-C-U-F1-... – 1506a English
Selection in the PARA menu
1 Continue to the next selection
2 Back to the previous selection
3 Confirm selection
6 Confirm selection and back to the main menu
2
a = DEADBAND
b = ½ DEADBAND
3
Parameter value
Increase value
Reduce value
Back to the selection
3
Upper limit (DEADBAND (+))
4
Lower limit (DEADBAND (-))
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