Walchem WebAlert WA500, Инструкция по эксплуатации

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Generic 4-20 mA Input
This type of analog input is programmed exactly like the Level type. The only difference is that the
Level type will calculate the Usage, while the Generic type will not.
Flow meter 4-20 mA Input
Input
Displays which 4-20 mA inputs have been selected as “Flow meter” type.
Custom Name
You may give the input a custom name by typing it into the text box.
Rate
This displays the current reading of the flow meter, using the mA signal from the device, the span of the
4-20 mA signal defined in “4 mA =” and “20 mA =” below, and the units of measure defined below.
Present mA
This displays the present raw mA signal from the flow meter. This is helpful in troubleshooting.
Status
This displays whether the present value is “Normal”, or in a “Low Alarm” or “High Alarm” condition.
Possible status messages are; Normal (everything is OK), Sensor Error (the sensor signal is not valid),
Over Range (between 20 and 21 mA), Under Range (between 3.9 and 4.0 mA), High Alarm, Low
Alarm or Total Limit.
4 mA =
Type into the text box the value that corresponds to a 4 mA output signal from the device. For example,
if the flow transmitter sends out 4 mA at 0.00 gpm, type in 0.00. Any value between –100,000 and
100,000 is acceptable.
20 mA =
Type into the text box the value that corresponds to a 20 mA output signal from the device. For
example, if the flow transmitter sends out 20 mA at 100 gpm, type in 100. Any value between –100,000
and 100,000 is acceptable.
Units
Type into the text box the units of measure that you want to use for the device connected to that input.
For example, you could use “gal”, etc.
Rate Low Alarm
Type into the text box the value for that input below which you want a 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 Alarm
Type into the text box the value for that input above which you want a 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.