Fluke 2620A User Manual

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Additional Considerations
Introduction
5
5-3
Introduction
Chapter 5 discusses some topics that will help you use the instrument more effectively.
These considerations assume that you are familiar with the basic operation of the
instrument and have some basic understanding of electronics.
Measurement Rate
The two measurement rates provide a choice of maximum accuracy and noise rejection
(slow rate) or maximum throughput (fast rate). The selected rate applies to all channels
on the instrument. Therefore, your rate selection will be based on overall consideration
of the speed and accuracy you need.
Exact measurement rates vary somewhat by type of measurement. Refer to Appendix A,
Specifications for complete measurement rate information.
Advanced Trigger Mechanisms
Normally, the built-in scan interval timer controls when scan measurements are taken.
However, two additional mechanisms are available for activating scans:
1.
 
An external trigger signal, connected at the rear panel "TR" input.
2.
 
An alarm condition on the Monitor channel.
Note
These two additional trigger mechanisms are mutually exclusive.
The External Trigger input and Monitor-Alarm trigger can be enabled from the front
panel or through computer interface commands
Front Panel Trigger Control
To access the trigger controls from the front panel, select TRIGS (
K M). Then press
G or G to cycle through the choices for trigger types:
OFF
Both External and Monitor-Alarm triggers are disabled.
On
The External Trigger input is enabled.
ALAr The Monitor-Alarm trigger is enabled.
Press 
EE once you’ve selected the desired trigger type. Note that internal scan
interval triggering is not affected by this selection and remains available.
Computer Interface Trigger Control
Select a scan trigger type over the computer interface by sending the command:
TRIGGER<type>
where <type> is:
0
Both External and Monitor-Alarm triggers are disabled.
1
The External Trigger input is enabled.
2
The Monitor-Alarm trigger is enabled.
If one of these types is not specified, an Execution Error is generated.