Agilent Technologies Agilent 34980A, User Manual

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Features and Functions
2
34980A User’s Guide 69
•
You can assign an alarm to any configured channel and multiple
channels can be assigned to the same alarm number. However,
you cannot assign alarms on a specific channel to more than one
alarm number.
• When an alarm occurs, the instrument stores relevant information about
the alarm in the queue. This includes the reading that caused the
alarm, the time of day and date of the alarm, and the channel number
on which the alarm occurred. The information stored in the alarm
queue is always in absolute time format and is not affected by the
FORMat:READing:TIME:TYPE
command setting.
• You must configure the channel (function, transducer type, etc.) before
setting any alarm limits. If you change the measurement configuration,
alarms are turned off and the limit values are cleared. Alarms are also
turned off when you change the temperature probe type, temperature
units, or disable the internal DMM.
•
If you plan to use scaling on a channel which will also use Mx+B
scaling,
be sure to configure the scaling values first . If you attempt to
assign the alarm limits first, the instrument will turn off alarms and
clear the limit values when you enable scaling on that channel. If you
specify a custom measurement label with scaling, it is automatically
used when alarms are logged on that channel.
• If you redefine the scan list, alarms are no longer evaluated on those
channels (during a scan) but the limit values are not cleared. If you
decide to add a channel back to the scan list (without changing the
function), the original limit values are restored and alarms are turned
back on. This makes it easy to temporarily remove a channel from the
scan list without entering the alarm values again.
• Each time you start a new scan, the instrument clears all readings
(including alarm data) stored in reading memory from the previous
scan. Therefore, the contents of reading memory are always from the
most recent scan.