Agilent Technologies Agilent 34980A, User Manual

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70 34980A User’s Guide
2
Features and Functions
•
As shown below, alarms are logged in the alarm queue only when a
reading crosses a limit, not while it remains outside the limit and not
when it returns to within limits.
• Four TTL alarm outputs are available on the rear- panel Alarms
connector. You can use these hardware outputs to trigger external alarm
lights, sirens, or send a TTL pulse to your control system.
You can also initiate a scan sweep (no external wiring required) when
an alarm event is logged on a channel. For complete details, refer to
“Using the Alarm Output Lines” on page 74.
• The following table shows the different combinations of front- panel
annunciators that may appear while using alarms. In addition to being
stored in reading memory, alarms are also recorded in their own SCPI
status system. You can configure the instrument to use the status
system to generate a Service Request (SRQ) when alarms are generated.
Refer to the Agilent 34980A
Programmer’s Reference for more
information on the Status System.
An alarm is enabled on the displayed channel.
The indicated HI or LO limit is being configured on the indicated alarm
(shown while in the Alarm menu).
An alarm has occurred on one or more channels. The behavior of the
Alarm Output lines tracks the alarm annunciators on the front panel.
The Alarm Output lines have been cleared but alarms remain in the queue.
Upper Limit
Lower Limit
Alarm Event No Alarm