Series 2280 Precision DC Power Supply Reference Manual
Appendix B: Verification
077085503 / March 2019
B-33
Check DC current readback accuracy (100 mA and 10 mA ranges)
Equipment required
AC power source
High current 18 AWG wire
300 Ω load resistor
High accuracy 0.05 Ω shunt and 5 Ω shunt
DC voltmeter
Current shunt resistor cabling
The Series 2280 has the following ranges to verify: 10 A, 1 A, 100 mA, and 10 mA. Follow the
procedures described below to check the current readback accuracy on 100 mA and 10 mA range.
For other ranges, refer to
Check DC current readback accuracy (10 A and 1 A ranges)
(on page B-
Set up the equipment as shown in the following figure.
Figure 109: Current readback accuracy on 100 mA and 10 mA ranges test setup
Make sure the warm-up criteria have been met, as described in the Performance verification
conditions.
To check DC current readback accuracy (100 mA and 10 mA ranges):
1. Set the voltmeter as follows:
a. Set to measure DC voltage.
b. Set the current range to autorange.
c.
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.
