How to test a battery charger?

When testing chargers I want to measure and record both current and voltage simultaneous for the full charge and know exactly when the charger says the battery is full. I have done this small write-up to show how I solved the above measurement task. Recording The measurement of voltage and current can be done with two DMM and to record the data I uses a computer connection from each meter. This was supposed to be easy enough, but the Fluke computer program could only handle one meter at a time, i.e. I had to do my own recording program. The computer interfaces for the meters uses an encapsulated IR link, i.e. the DMM has absolutely no electrical connection to the computer or to the other DMM. The encapsulation secures that I can use multiple meters close together without interference.