Figure 4-11: List Transients - Ametek California Instruments MX15 Series User Manual

4.7.5 List Transients
List transients provide the most versatile means of controlling the output in a specific manner as
they allow a series of parameters to be programmed in a timed sequence. The following figure
shows a voltage output generated from a list. The output shown represents three different AC
voltage pulses (160 volts for 33 milliseconds, 120 volts for 83 milliseconds, and 80 volts for 150
milliseconds) separated by 67 milliseconds, zero volt intervals.
Transient list programming is supported from the front panel and may be accessed by selecting
the TRANSIENTS menu. Transient lists can also be programmed over the bus. Refer to the
SCPI Programming Manual for more information about programming List transients and triggers
over the bus.
The list specifies the pulses as three voltage points (point 0, 2, and 4), each with its
corresponding dwell point. The intervals are three zero-voltage points (point 1, 3, and 5) of equal
intervals. The count parameter causes the list to execute twice when started by a single trigger.
The output transient system allows sequences of programmed voltage and or frequency
changes to be executed in a time controlled manner. Changes can be either step changes
(maximum slew rate) or ramps (specified slew rates).
The section provides some examples of programming output changes (transients). Transients
are defined as a series of numbered steps in a list. The list is executed sequentially. Each step
has a number of fields that can be set by the user:
Voltage, Voltage slew rate, Frequency, Frequency slew rate, Current, Function, Dwell
time, Trigger out.
The voltage, current and frequency settings are the same as one would do from the setup
screen using the shuttle knob or keypad. At each step, the output will be set to the specified
voltage, current and/or frequency. The rate of change for voltage and frequency is determined
by the slew rate set. Current slew is fixed at MAX and cannot be programmed.
If the voltage is changed from 10 Vac to 20 Vac and the V slew is set to 100 V/sec, the voltage
will ramp from 10 to 20 Vac in 100 ms. ( [20 - 10] / 100 = 0.1 sec). The dwell time is the time the
output will remain at this setting. In this example, it should be set long enough to reach the final
programmed value of 20 Vac, e.g. it should be at least 0.1 sec. If not, the voltage will never
reach the final value of 20 Vac before the next step in the transient list is executed. The dwell
time may be set longer than 0.1 sec in this example. If for example the dwell time is set to 1.0
sec, the voltage will ramp from 10 Vac to 20 Vac over a 0.1 sec period and then remain at 20
Vac for 0.9 sec.
MX15 Series

Figure 4-11: List Transients

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