Agilent Technologies E3632A manual Normal Mode Voltage Noise CV Ripple and Noise

Chapter 3 Calibration Procedures

Constant Voltage (CV) Verifications

2Connect the ac power line through a variable voltage transformer.

3Turn on the power supply. Select the 30V/4A range, enable the output, and set the display to the limit mode. When the display is in the limit mode, program the current to the full rated value (4.0A) and the voltage to full rated value (30.0V).

4Operate the electronic load in constant current mode and set its current to 4.0A. Check that the CV annunciator remains lit. If not lit, adjust the load so that the output current drops slightly until the CV annunciator lights.

5Adjust the transformer to low line voltage limit (104 Vac for nominal 115 Vac, 90 Vac for nominal 100 Vac, or 207 Vac for nominal 230 Vac). Record the output reading on the digital voltmeter.

6Adjust the autotranformer to high line voltage (127 Vac for nominal 115 Vac, 110 Vac for nominal 100 Vac, or 253 Vac for nominal 230 Vac). Record the voltage reading on the digital voltmeter. The difference between the digital voltmeter readings in steps (5) and (6) is the CV line regulation. The difference of the readings should be within the limit of 5mV.

Normal Mode Voltage Noise (CV Ripple and Noise)

The normal mode voltage noise is in the form of ripple related to the line frequency plus some random noise. The normal mode voltage noise is specified as the rms or peak-to-peak output voltage in a frequency range from 20 Hz to

20 MHz.

1 Turn off the power supply and connect the output to be tested as shown in Figure 3-1to an oscilloscope (ac coupled) between (+) and (-) terminals. Set the oscilloscope to AC mode and bandwidth limit to 20 MHz. Connect a resistive load (7.5W) as shown in Figure 3-1.

2Turn on the power supply. Select the 30V/4A range, enable the output, and set the display to the limit mode. When the display is in the limit mode, program the current to the full rated value (4.0A) and the voltage to the full rated value (30.0V).

3Check that the front panel CV annunciator remains lit. If not lit, adjust the load down slightly.

4Note that the waveform on the oscilloscope does not exceed the peak-to-peak limit of 2 mV.

5Disconnect the oscilloscope and connect an AC rms voltmeter in its place. The rms voltage reading does not exceed the rms limit of 0.35 mV.

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