Model 2281S-20-6 DC Power Supply and Battery Simulator Reference Manual
Section 4: Measurement optimization
077114601 / March 2019
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The 2281S uses the open circuit measurement method to measure ESR in the battery test function.
Figure 112: Open circuit ESR measurement
Measurement process:
1. The 2281S is set to a high-
resistance state (approximately 130 kΩ).
2. Measure the open circuit voltage Voc.
3. The instrument starts to output power.
4. Set the output voltage as Voc + 200 mV, and set the Delay.
5. After the delay time, measure the voltage and the current of the battery when they are stable.
6.
The instrument computes the battery resistance using ESR =∆V/ ∆I.
You must set a suitable delay time in order to get an accurate ESR measurement.
You can gradually increase the delay time until the delay time change does not affect the result
significantly.