Service Guide
5
Keysight U8001A/U8002A User’s and Service Guide
73
CC source effect (line regulation)
This test measures the change in output current that results from a change in AC
line voltage from the minimum value to the maximum value.
Procedures:
1
Power off the power supply and connect the output to be tested as shown in
with the DMM connected across the current monitoring resistor
(R
M
).
2
Connect the AC power line through an AC voltage source. Adjust the AC
voltage source to provide nominal input voltage to the power supply.
3
Power on the power supply.
4
When the display is in the limit mode, program the output voltage to maximum
programmable value and output current to full rated value, i.e. 3 A for U8001A
and 5 A for U8002A.
5
Enable the output.
6
Operate the electronic load in constant voltage mode and set its voltage to 30 V.
Ensure that the power supply is in CC mode. If not, adjust the electronic load so
that the output voltage drops slightly until the power supply is in CC mode.
7
Adjust the AC voltage source to low line voltage limit. Record the output
current reading by dividing the voltage reading on the DMM by the resistance
of the current monitoring resistor.
8
Within a few seconds after step 7, adjust the AC voltage source to high line
voltage limit and record the output current reading by dividing the voltage
reading on the DMM by the resistance of the current monitoring resistor.
9
Compare the reading obtained in steps 7 and 8. The difference should be
within the limit of:
– U8001A: 2.6 mA
– U8002A: 3 mA
Line voltage
Low line voltage limit,
V
ac
High line voltage limit,
V
ac
100
90 110
115
104
127
230
207
253
