Technical data

Service Guide 5
U8001A/U8002A User’s and Service Guide 71
CV Source Effect (Line Regulation)
This test measures the change in output voltage that results
from a change in AC line voltage from the minimum value to
maximum value.
Procedures:
1 Power- off the power supply and connect a DMM between
the (+) and (–) terminals of the output to be tested as
shown in Figure 5- 7(A).
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 full rated value, i.e. 30 V and output
current to the maximum programmable value.
5 Enable the output.
6 Operate the electronic load in constant current mode and
set its current to 3 A for U8001A and 5 A for U8002A.
Ensure that the power supply is in CV mode. If not,
adjust the electronic load so that the output current drops
slightly until the power supply is in CV mode.
7 Adjust the AC voltage source to low line voltage limit.
Record the output reading on the DMM.
8 Within a few seconds after step 7, adjust the AC voltage
source to high line voltage limit and record the voltage
reading on the DMM.
9 The difference between the DMM readings in steps 7 and
8 should be within the limit of 5 mV.
Line Voltage Low Line Voltage Limit, V
ac
High Line Voltage Limit, V
ac
100 90 110
115 104 127
230 207 253