Walchem WebMaster ONE Instruction Manual page 133

Maximum Output Allowed
Type in the text box the highest % output allowed for the analog output. Generally this will be
100%.
Input Value when Output is Max
Type in the test box the analog or sensor input value where the output needs to be at its maximum
allowed value. This will set the control direction and the proportional band. If the process value
will normal trend above the set point, and the desired action is to drive it back down, set the Input
Value when Output is Max to a value greater than the set point. The closer this value is to the set
point, the steeper the proportional response, and the more likely to overshoot the set point.
Damping
The response of the output to changes in the assigned input readings can be delayed by using the
damping feature. Set to 0 and the output will respond immediately. Set above 0 and the readings
will be averaged over that amount of time before calculating an output response.
Input Fault Value
If the analog output is suspended due to an error in the sensor or analog input signal, the Analog
Output will default to this set value. Type the desired output in % in the text box. If you want the
pump to shut off, enter 0%.
Interlock Value
If the analog output is Interlocked by a digital input, or a relay output, or by another analog output,
the Analog Output will default to this set value. Type the desired output in % in the text box. If
you want the pump to shut off, enter 0%.
During Input Calibration
Click on the radio button to select how you want the analog output to react during calibration of
the input:
Remain Active: The Output % continues to respond to changes as normal.
Set Value: When the calibration begins the Output % is forced to the Input Cal Set Value (see
below). Normal response resumes once the calibration is complete.
Last Value: When the calibration begins the Output % is frozen at the last value calculated before
the calibration.
Normal response resumes once the calibration is complete.
Input Cal Set Value
Appears if the Set Value response is selected for During Input Calibration. Type the fixed output
% desired during calibration of the sensor inputs.
Mutual Interlocks
Click the check boxes to select or de-select the relays and analog output control outputs that you
want to be prevented from turning ON if this output is already ON. If you do not need any other
output to shut off when this output turns on, UNCHECK all boxes. The selection is mutually
exclusive, meaning that if Relay 2 has Relay 4 interlocked, then R2 won't turn on if R4 is already
on, and R4 won't turn on if R2 is already on. This feature should be used with caution since it can
potentially delay a chemical addition for a long time.
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