Model 2281S-20-6 DC Power Supply and Battery Simulator Reference Manual
Appendix B: Verification
077114601 / March 2019
B-31
To check sink current readback accuracy (100 mA and 10 mA ranges):
1. Set the voltmeter as follows:
Set to measure DC volts.
Set the current range to autorange.
Calculate the amperes (instead of volts) by multiplying the voltmeter reading result by 1/(R1+R2), where
R1 and R2 separately represent the high-
accuracy 0.05 Ω shunt and 5 Ω shunt.
2. Check the current readback accuracy on the 100 mA range.
3. Set the DUT output voltage to 0 V.
4. Set the output voltage of the DC source to 20 V, set the DC source current to 10% of the test
current. See the following table.
Equipment
Range
10% test current
(mA)
50% test current
(mA)
100% test current
(mA)
DC source
100 mA
10
50
100
10 mA
1
5
10
5. Turn the DUT output on.
6. Enter the voltmeter reading/(R1 + R2) in the DC current readback accuracy table.
7. Enter the DUT current readout in the DC current readback accuracy table under the current
readout column.
8. Calculate the difference of the two measurements taken in steps 7 and 8. Enter the absolute
value of the calculated value in the difference column of the DC current readback accuracy table.
9. Increase the DUT output current to 50% of full-scale output current and repeat step 6 through
step 9.
10. Increase the DUT output current to 100% of full-scale output current and repeat step 6 through
step 9.
11. Repeat step 3 through step 12 to check current readback accuracy on the 10 mA range.
