Menu: Controller - ABB PositionMaster EDP300 Operating Instruction

PositionMaster EDP300 DIGITAL POSITIONER | OI/EDP300-EN REV. D

Menu: Controller

Menu / parameter Value range
Controller
Zone 1 to 100 in steps of 1
Dead Band 0.10 to 10.00 % in steps of
0.01 %
Dead Band Calc. Active, inactive
DB Approach Fast
Medium
Slow
DB Control time 0 to 30 s
DB Close-Up Range 0 to 1000 s.
Description
This parameter specifies the point at which the control structure is switched over when the dead band
is being approached.
Note
On valves where slip-stick effect is significant, valve vibration can be reduced by increasing the value of
the 'Zone' parameter.
The dead band defines a +/ range around the position set point. Once the valves and fittings reach this
range, the positioner maintains this position.
Use this function to activate / deactivate the control behavior on the dead band.
This parameter specifies the speed at which the dead band is approached.
In rare cases, overshooting can occur when the valve position is being compensated. This can be
prevented by reducing the speed of the dead band approach (DB Approach).
In some cases it can happen that the valve continues moving slowly after reaching the dead band and
leaves the dead band again. To prevent this, this parameter can be used to specify how long the
controller should be active after reaching the dead band.
Factory setting: 0 s
Use this parameter to enter a monitoring time up to the point at which the dead band is reached.
When the dead band is exceeded, the monitoring time is started.
If the dead band around the new position set point is not reached again within the specified time, an
alarm is triggered.
Once the set point has been reached, the alarm is automatically reset.
Note
• With active shutoff there is no alarm message.
Once the set point has been reached, the alarm is automatically reset.
• The monitoring stroke time is determined during automatic adjustment. Selecting a value of '0 s'
deactivates this parameter.
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