Testing and Characterizing Batteries Using the Circuit Specialists CSI3721A Programmable DC Electronic Load

The Circuit Specialists CSI3721A Programmable DC Electronic Load is a full featured Electronic Load with a built in Battery testing algorithm. This feature makes testing and characterizing of battery packs extremely easy to perform. This application note will describe the sequence of steps necessary to determine the Amp/Hour rating of a battery pack. The CSI3721A Programmable DC Electronic Load is ideally suited for testing any battery but especially rechargeable battery packs such as Li-Ion because the discharge termination voltage can be set to avoid discharge below the safe voltage limit. This allows unsupervised discharge of the battery pack under test. 1.) Power ON the CSI3721A and Press the INPUT ON/OFF button to disable the Load and then connect the battery pack observing polarity. 2.) Press and Release the 2nd button then Press the 6 (Battery) button to enter the battery discharge mode of operation. 3.) Press the SET button and enter the desired discharge parameters using the ↑ and ↓ buttons to select the parameter, and the ← and → buttons together with the rotary knob or numeric keypad to enter desired values for termination voltage and discharge current. 4.) Press the CLEAR button to exit the parameter entry screen. 5.) Press the INPUT ON/OFF button to begin the automatic battery discharge test. 6.) The CSI3721A will proceed to discharge the battery at the discharge current value set in step 3 and will automatically stop the discharge test of the battery when the battery voltage equals the value set. At this time the elapsed time that was required to discharge the battery and the Amp/Hr rating of the battery may be viewed on the LCD screen. 7.) To exit the battery discharge mode of operation, press and release the 2nd button then press the 6 (Battery) button.