Keysight E3631A, Service Manual

Page: 73 / 131

Calibration Procedures 3
Keysight E3631A Service Guide 71
7 Repeat steps (1) through (6) for the remaining outputs.
Normal mode current noise (CC ripple and noise)
The normal mode current noise is specified as the rms output current in a
frequency range 20 Hz to 20 MHz with the power supply in constant current
operation.
1 Turn off the power supply and connect the output to be tested as shown in
Figure 3-1 with a load resistor (1.2? for +6V supply and 25? for ±25V supplies)
across output terminals to be tested. Connect a rms voltmeter across the load
resistor. Use only a resistive load for this test.
2 Turn on the power supply and select the output to be tested using the meter
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 to
full-scale value and the voltage to the maximum programmable value.
3 The output current should be at the full-scale rating with the CC annunciator
on. If not lit, adjust the load so that the output voltage drops slightly until the
CC annunciator lights.
4 Divide the reading on the rms voltmeter by the load resistance to obtain rms
current. The readings should be within the limit specified below for each
output tested.
5 Repeat steps (1) through (4) for the remaining outputs.
Output Specification
+6V Output 2 mA
+25V Output 0.5 mA
-25V Output 0.5 mA