Compliance West MegaPulse 2x10s-2.5, Инструкция по эксплуатации

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14
Initial Checkout Procedure
The following procedure will verify that the
Tester is working correctly. We recommend that
this procedure be conducted periodically to
ensure proper operation of the Tester.
The following items are needed to conduct this
procedure:
A measuring instrument to monitor the
output waveform. Always ensure that the
measuring instrument (usually an
oscilloscope with a high-voltage probe) is
rated for the voltage involved, and that the
frequency response of the instrument and
probe are capable of measuring the output
waveform of the MegaPulse Impulse
Tester. A measuring instrument or probe
with a low frequency response will result
in erroneous readings that could be mis-
read.
CAUTION
High voltage generated by the
MegaPulse tester is exposed
during this test. A risk of shock
exists. Exercise care when using
the MegaPulse tester.
1. Connect the Tester to a proper source of
supply using the included 18 AWG power
supply cord. Make sure that the front
panel
VOLTAGE adjust know is turned
fully counterclockwise.
2. Plug the Output and Return test leads in
to the jacks on the front panel.
3. Connect the ends of the test leads to an
appropriate measuring instrument
(typically an oscilloscope with a high-
voltage probe). Note that the
RETURN
lead is referenced to the chassis of the
MegaPulse tester.
4. Turn the Tester on. Toggle the
POLARITY switch if necessary so that
the NOR indicator is lit.
5. Note that the Voltage meter may
indicate that some residual voltage is
present on the main storage capacitor,
even when the tester is first turned ON.
This is due to inherent charging of the
internal capacitors. Pressing the
TRIGGER switch will discharge the
capacitors (be sure not to touch the output
and return leads when pressing the trigger
switch).
6. Push the yellow CHARGE button.
Verify the red TRIGGER indicator is
now lit.
7. Adjust the VOLTAGE knob so that the
front panel LED display is reading a
voltage that is suitable for the measuring
instrument that is being used. Push the red
TRIGGER button, and view the resulting
impulse waveform on the measuring
instrument.
8. Note that the peak amplitude of the
measured output waveform is
proportional to the voltage that is read of
the front panel of the MegaPulse, but it
will always be somewhat lower. This is
because the meter on the MegaPulse is
measuring the voltage on the main
impulse storage capacitor (C1 in Figure
1). This voltage will intentionally
dissipate to some extent before reaching
the output leads. Therefore, it is
important to measure the peak amplitude
of the output waveform, and adjust the
output of the MegaPulse accordingly.
9. Repeat steps 5 through 8, except this
time toggle the POLARITY switch so
that the REV indicator is lit. Note that the
impulse waveform will now be a negative
pulse, so it will probably be necessary to
make adjustments to the measuring
instrument to get a proper reading.
10. Adjust the VOLTAGE knob fully
counterclockwise, to the minimum
position. Turn the rear-panel power
switch OFF.
NOTE: Steps 11-17 apply only to MegaPulse
models with a defined current output
waveform (with 2 waveform definitions
in the Model Number). MegaPulse
models with a single waveform
definition in the Model Number are
voltage waveform testers and the
following steps need not be conducted.
11. Connect the Output and Return test
leads across an appropriate current shunt,
so that the Output lead is connected to one
end of the current shunt, and the Return
lead is connected to the other end of the
current shunt. An example of a current
shunt is shown here. If this current shunt
example is used, calculate the current
output using the measured resistance of
the