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METER VALIDATION
If two methods of measuring output power vary by more than a small amount, it brings metering validity into
question and should be investigated. If you have more than one way of determining output power, you can
validate your meter samples by constantly comparing in real-time. Here is an example:
Meter 1 is XMTR Power Out
Meter 2 is ANT Power In
The expression to compare the two values (in percent) is:
(M2
–
M1)/M1*100
You can now set an alarm on this channel to be alerted when the difference is more than, say, 1 percent. You could
also compare direct and indirect power and do the same thing, but alarms on efficiency work just as well.
STATUS BASED ON ANALOG LIMITS
You can also set a channel based on analog limits. While you would normally alarm on limits, there may be
situations where you would prefer to log values as a status rather than an alarm. Here is an example assuming
Meter 1 is Power Out. A status channel is set to be virtual and the following expression is entered:
(M1 > 90) AND (M1 < 105)
STATUS FOR MULTIPLE EVENTS
Sometimes it is nice to have a single status channel alert us to one of several possible problems. A virtual status
channel does this very well.
Assume the following conditions all indicate trouble:
Status 1 = Silence Sense
Meter 1 (Power Out) < 4500
Meter 2 (Temperature) > 90
Here is our master status channel for the site:
S1 OR (M1 < 4500) OR (M1 >90)
