Keysight E3631A, Service Manual

Page: 66 / 131

3 Calibration Procedures
64 Keysight E3631A Service Guide
current of the selected output to the maximum programmable value and the
voltage to the full-scale value (see Table 3-2 ).
4 Record the voltage across RS and convert it to current by dividing by the
resistance (DVM reading/100 k W ). Note that the current is less than 1.5 m A for
each of the three outputs.
5 Repeat steps (1) through (4) for the remaining outputs.
Load transient response time
This test measures the time for the output voltage to recover to within 15 mV of
nominal output voltage following a load change from full load to half load, or half
load to full load.
1 Turn off the power supply and connect the output to be tested as shown in
Figure 3-1 with an oscilloscope. Operate the electronic load in constant
current mode.
2 Turn on the power supply and select the 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 to the maximum programmable value and the voltage to the full-scale
value (see Table 3-2 ).
3 Set the electronic load to transient operation mode between one half of the
output's full scale value and the output's full scale value at a 1 kHz rate with
50% duty cycle.
4 Set the oscilloscope for ac coupling, internal sync, and lock on either the
positive or negative load transient.
5 Adjust the oscilloscope to display transients as shown in Figure 3-5 . Note that
the pulse width (t2-t1) of the transients at 15 mV from the base line is no more
than 50 ?sec for each of the three outputs.
6 Repeat steps (1) through (5) for the remaining outputs.