Compliance West MegaPulse 2x10s-2.5, Instruction Manual

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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.
10. Repeat steps 5 through 9, 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.
11. Adjust the VOLTAGE knob fully
counterclockwise, to the minimum
position. Turn the rear-panel power
switch OFF.
12. 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.
13. Connect the measuring instrument
across the current shunt, keeping in mind
that the Return lead is referenced to
ground.
14. Turn the Tester on. Toggle the
POLARITY switch if necessary so that
the NOR indicator is lit.
15. Push the yellow CHARGE button.
Verify the red TRIGGER indicator is
now lit.
16. 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.
17. Compare the impulse waveform to the
appropriate ideal waveform that is
included at the end of this manual (figures
8 and 9). Note that the measured
waveform may differ from the "ideal"
waveform because of lead inductance,
inductance of the current shunt, etc. It is
often difficult to make a comparison
between the "real world" and the "ideal
case" because these inductances will have
a significant effect on the high-current
output waveform. If the measured
waveform is significantly different than
the ideal waveform, then additional
evaluation and/or repair of the MegaPulse
tester is warranted.
18. Repeat steps 14 through 17, 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.
19. Adjust the VOLTAGE knob fully
counterclockwise, to the minimum
position. Turn the rear-panel power
switch OFF.
If the results of the performance test are not in
accordance with the above, service is required.
Remove the Tester from service and contact the
manufacturer for servicing information. If the
results of the tests above are correct, proceed
with the Calibration Procedure.
Calibration Procedure
The Calibration Procedure should be performed
annually and any time the instrument has been
repaired. The calibration procedure consists of
calibrating the meter reading to agree with the
voltage output.
The Performance test in the previous section
should be performed with satisfactory results
before conducting the Calibration procedure.
Before starting the Calibration procedure,
perform the Calibration access procedure given
earlier in this Section.
NOTE
Allow the instrument to stabilize for
approximately five minutes. Perform
all calibration adjustments at an
ambient temperature of 23
°
C
±
5
°
C
(73
°
F
±
9
°
F).
WARNING:
Calibration Adjustments Are
Performed On Live Circuits.
Exercise Caution At All Times, And
Use A Non-Conductive Tool For All
Adjustments.
Voltage Calibration Adjustment
Use the following procedure to calibrate the
output voltage. Pot R6 and R7 are located on the
back side of the front panel LED display board.
Verify the location of these two potentiometers
after the top cover of the tester has been
removed, but before the power cord has been