Keysight Technologies N69100 Series, Руководство по эксплуатации и обслуживанию

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Step 4. Record the output voltage reading from the DMM.
Step 5. Turn off the output of the RP79xxA load. Record the voltage reading from the DMM again. The
difference between the DMM readings in steps 4 and 5 is the load effect, which should not exceed the
value listed in the test record form for the appropriate model under “CV Load Effect”.
Constant Voltage Ripple and Noise
Periodic and random deviations in the output combine to produce a residual AC voltage superimposed
on the DC output voltage. This residual voltage is specified as the rms or peak-to-peak noise in the
indicated frequency range (refer to the
Specifications section).
Step 1. Turn off the unit under test. Connect the RP79xxA load unit, differential amplifier, and an
oscilloscope (ac coupled) to the output (see
Test Setup C ).
Step 2. As shown in the diagram, use the differential probes to connect the differential amplifier to the
+ and - output terminals. The shields of the two probes should be connected together. Connect the
output of the differential amplifier to the oscilloscope with a 50
Ω termination at the input of the
oscilloscope.
Step 3. Set the probe to 1:100 and set the inputs of the differential amplifier to match the probe
setting. Set the inputs to AC coupling. Set the input resistance to 1 M
Ω . Set the oscilloscope’s time
base to 5 ms/div, and set the vertical scale to the maximum sensitivity without clipping the waveform.
Turn the bandwidth limit on (usually 20 MHz), and set the sampling mode to peak detect.
Step 4. Turn on the unit under test and program the instrument settings as described in the in the test
record form under “CV Ripple and Noise”. Turn the output on. Program the RP79xxA load as shown in
the test record card and turn the output on. Let the oscilloscope run for a few seconds to generate
enough measurement points. On the Keysight Infiniium scope, the maximum peak-to-peak voltage
measurement is indicated at the bottom of the screen on the right side. The result should not exceed
the peak-to-peak limits in the test record form under “CV Ripple and Noise, peak-to-peak”.
If the measurement contains any question marks, clear the measurement and try
again. This means that some of the scope data received was questionable.
Step 5. Disconnect the oscilloscope and connect an rms voltmeter in its place. Do not disconnect the
50 ohm termination. Divide the reading of the rms voltmeter according to the differential amplifier
setting. The result should not exceed the rms limits in the test record form for the appropriate model
under “CV Ripple and Noise, rms”.
Transient Recovery Time
This test measures the time for the output voltage to recover to within the specified value following a
50% change in the instrument's rated load current.
Step 1. Turn off the unit under test. Connect an oscilloscope with the specified probe across the sense
terminals (see
Test Setup A ). Connect the RP79xxA load unit to the output terminals.
Step 2. Turn on the unit under test and program the instrument settings as described in the test record
form under “Transient Response”.
6 Verification and Calibration
232 Keysight N69100 Series Operating and Service Guide