General Information - 2
List Operation
List mode lets you generate complex sequences of input changes with rapid, precise timing, which may be synchronized with internal or external signals. This is useful when running test sequences with a minimum amount of programming overhead.
You can program up to 50 settings (or steps) in the list, the time interval (dwell) that each setting is maintained, the number of times that the list will be executed, and how the settings change in response to triggers. All listed data is stored in a
List steps can be either individually triggered, or paced by a separate list of dwell times which define the duration of each step. Therefore, each of the up to 50 steps has an associated dwell time, which specifies the time (in seconds) that the input remains at that step before moving on to the next step. See chapter 5 for detailed information about programming lists from the front panel.
Triggered Operation
The electronic load has various triggering modes to allow synchronization with other test equipment or events. The triggering circuits are located in the mainframe, and all modules receive the trigger simultaneously (although each module is programmed individually as to what operation, if any, will be triggered. As described previously, triggering can be used for the following applications:
Triggering a preset level | Transfers all pending preset levels to the actual level. For the presently active |
| mode, the new level appears at the input. For the modes which are not presently |
| active, the preset levels will not take effect at the input until the applicable |
| mode becomes active. |
Triggering a transient pulse | Generates a transient pulse of programmable width when pulsed transient |
| operation is in effect. |
Toggling | Changes the input between the main level and the transient level when toggled |
| transient operation is in effect. |
Triggers can be sent from the front panel by pressing the Trigger key. However you must first initiate the trigger function by executing the TRIG:IMMED command located in the Trigger Control menu.
Three triggering methods are available over the GPIB: the GET function, the *TRG common SCPI command, and the TRIG subsystem SCPI command (refer to Programming Guide). The SCPI TRIG subsystem allows you to select either the ac line frequency, internal timer, or TRIG command as the trigger source. There is also a TRIGGER connector on the rear panel for external trigger inputs.
*TRG and the TRIG command are both synchronous with other commands; that is, the modules are not triggered until pending operations are completed. GET, external triggers,
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