Walchem WebAlert WA500, Instruction Manual

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Rate Low-Low Alarm
Type into the text box the value for that input below which you want a low-low alarm to occur. Any
value between –100,000 and 100,000 is acceptable. You must go to the Alarm page to specify that this
alarm condition is a critical alarm in order to close the alarm relay or send an email.
Rate High-High Alarm
Type into the text box the value for that input above which you want a high-high alarm to occur. Any
value between –100,000 and 100,000 is acceptable. You must go to the Alarm page to specify that this
alarm condition is a critical alarm in order to close the alarm relay or send an email.
Alarm Dead Band
Type in the text box the dead band to be used for each alarm set point.
Damping
Damping is applied to the input by taking a running average of the readings of the input signal over the
time frame specified by the damping setting (0-60 seconds)
.
The averaged reading is displayed and used
for control. Type in the text box the desired time frame.
Total
This field displays the total flow accumulated since the last time it was reset.
Reset Total
Click on this button to reset the total.
Last Reset Date
This field displays the date and time of the last time the total was reset.
Total Alarm Limit
Type into the text box the total volume of flow above which the alarm will activate.
5.5 4-20 mA Calibration
Set 4 mA
Following the instructions for your 4-20 mA transmitter, supply the WebMaster Industrial Water with a
4 mA signal from each transmitter. You should verify that the transmitter is accurate by measuring the
output with an ammeter. You can read the present value of the mA signal as measured by the
WebMaster Industrial Water in the second column of the table. If the present value is not exactly 4 mA,
click on the “Set 4 mA” button. You will be asked to verify that you want to change the calibration.
Once this is done, the controller will read the transmitter signal as exactly 4 mA.
Set 20 mA
Repeat this process, supplying the WebMaster Industrial Water with a 20 mA signal from each
transmitter, and click on the “Set 20 mA” button in order to calibrate the controller.