Keysight E3631A, Service Manual

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3 Calibration Procedures
60 Keysight E3631A Service Guide
5 Repeat steps (1) through (4) for the remaining outputs.
CV line regulation
This test measures the immediate change in output voltage that results from a
change in ac line voltage from the minimum value (10% below the nominal input
voltage) to maximum value (10% above the nominal input voltage).
1 Turn off the power supply and connect a digital voltmeter between the (+) and
(-) terminals of the output to be tested as shown in Figure 3-1 .
2 Connect the ac power line through a variable voltage transformer.
3 Turn on the power supply and select the desired output to be tested using the
meter and adjust selection key on the front panel. Enable the outputs and set
the display to the limit mode. When the display is in the limit mode, program
the current of the selected output to the maximum programmable value and
the voltage to full rated value (see Table 3-2 ).
4 Operate the electronic load in constant current mode and set its current to the
full rated value (see Table 3-2 ) of the output to be tested. Check that the front
panel CV annunciator remains lit. If not lit, adjust the load so that the output
current drops slightly until the CV annunciator lights.
5 Adjust 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.
6 Adjust 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 immediately. The difference between
the digital voltmeter readings in steps (5) and (6) is the CV line regulation. The
difference of the readings during the immediate change should be within the
limit specified below for each output tested.
Output Difference
+6V Output 2.6 mV
+25V Output 4.5 mV
-25V Output 4.5 mV