Agilent Technologies E3646A, User Manual, Page: 187 / 211

Appendix Service Information
Constant Voltage (CV) Verifications
187
Service
Information
1 Turn off the power supply and connect the output to be tested as shown in Figure A-
1 to an oscilloscope (ac coupled) between (+) and (-) terminals. Set the oscilloscope
to AC mode and bandwidth limit to 20 MHz. Connect a resistive load (13.5
Ω
)
‡
to
the terminal at (B) as shown above.
2 Turn on the power supply. Select the high voltage range (20V/1.5A)
†
, 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 scale rated value (1.5 A)
†
and the voltage to the full
rated value (20.0 V)
†
.
3 Check that the front panel
CV
annunciator remains lit. If not lit, adjust the load down
slightly.
4 Note that the waveform on the oscilloscope does not exceed the peak-to-peak limit
of (5 mV)* or (8 mV)**.
5 Disconnect the oscilloscope and connect the ac rms voltmeter in its place according
to the VRMS measurement techniques on page 186 and as shown on the previous
page. The rms voltage reading does not exceed the rms limit of
0.5 mV* or 1 mV**.
6 Repeat steps (1) through (5) for the other output.
*For E3646A/48A models. **For E3647A/49A models.
†
For E3646A model, and see
Table A-3
for other models
.
‡
For E3646A model, and see
Table A-2
for other models
.