User Manual – Rev BE AMETEK Programmable Power
MX Series 121
TRIG SOURCE The trigger source selects the event that will trigger a
measurement acquisition. Available options for this field
are IMM (immediate), PHASE A or SET VOLT. The IMM
trigger source causes the acquisition to trigger
immediately when the ENTER key is pressed on the
START field. Essentially, this is an asynchronous trigger
event. The acquisition will always be triggered in this
mode and data is available immediately.
The PHASE A source will cause the acquisition to trigger on the occurrence of a
set phase angle for the voltage on phase A. The trigger source is always phase
A when in this mode, regardless of the phase selection shown in the top right
corner of the display. When the acquisition is started, the acquisition system
waits for the specified phase angle to occur before triggering the acquisition.
This mode allows exact positioning of the acquisition data window with respect
to the voltage waveform.
The SET VOLT mode causes the acquisition to trigger at the specified voltage.
This mode also programs the selected phase or all three phases when the
measurement is started from the START field. As such, this trigger source
selection also programs the output voltage to the selected rms level.
TRIG PHASE / SET VOLT This field changes purpose, depending on the trigger
source selected immediately above it. If the trigger
source equals IMM or PHASE A, this field can be used to
program the trigger phase angle (TRIG PHASE). In IMM
mode, the value of this field is ignored.
If the trigger source is set to SET VOLT, this field can be used to specify the rms
voltage to program the output to and trigger the measurement on. The voltage
value set here should not exceed the maximum voltage range selected or the
rms capability for the wave shape selected on the phase or phases
programmed.
TRIG DELAY The trigger delay field allows the trigger point to be
positioned anywhere in the acquisition window. A
negative value will provide pre-trigger information on
data leading up to the trigger event. The pre-trigger
delay cannot exceed the length of the acquisition
buffer. See paragraph 4.6.3.3 for details. A positive
trigger delay positions the data window after the trigger
event. Positive trigger delays can exceed the length of
the acquisition buffer in which case the trigger event
itself will no longer be in the buffer. The maximum
value of the trigger delay is 1000 ms. The default
trigger delay value is 0.0 ms, which puts the trigger
event at the beginning of the acquisition window.