Relay (1-8) Output Menus - Time Proportional Types - Walchem WebMaster ONE Instruction Manual

6.20 Relay (1-8) Output Menus – Time Proportional Types
This page is used to select the set point, proportional band, etc. In time proportional control, the
WebMasterONE will look at the process value and compare it to the set point value. If the set
point is not satisfied, the controller will calculate an output on-time that will vary in proportion to
the deviation from that set point. The user defines the time period, and the proportional band away
from the set point where the relay will stay active for the entire time period.
Which units of measure appear depends upon how the input assigned to the relay is configured. If
you make changes to the Input Assignment, you will need to click on the "Submit" button in order
to see all the correct units.
You may also change the Relay Control Mode here. If you do, you will have to reselect the Input
Assignment as well.
This section assumes that the Relay Control Mode is set to Time Proportional. Other control mode
types are described in sections to follow.
Relay Control Mode
Click on the arrow of the pull down menu and select the way that you want to control the relay.
See Section 6.2 for details on each control mode.
Relay Input Assignment
Click on the arrow of the pull down menu and select the input that will be used to control the
relay. See Section 6.2 for details.
Current Reading
This field is for information only, and will display the calibrated reading from the sensor that is
assigned to control the relay.
Status
This menu is for information only, and displays whether the output is "Off" or "On" and if on, for
how much time, as well as any alarm conditions. Possible status messages are; Off, Off/Manual,
On/Time counting up (if activated based on sensor input), or On/Time counting down/Hand (for
manual relay activation). Possible error messages are Timeout and Interlock. See Section 8.1 for a
complete description of error messages.
Reset Timeout
There is a button called "Reset Timeout" which is used to reset the output if it has been activated
for longer than the time limit imposed in the "Output Time Limit" menu described below.
Custom Name
This menu allows you to rename the output if desired. Type the new name into the text box.
Set Point
Type in the text box the process value at which you want the relay to activate. The set point value
is limited to the range of the assigned input.
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