/diy/ - Do It Yourself

>>1413776
1) For low voltage stuff pretty much anything will be fine. Assuming you'll only be taking measurements of actually sine waves not having tRMS isn't a problem - it's only for non-sinusoidal waveforms.

2) Starter motors draw >200A on startup - it's not reliant on your charger, it's reliant on your battery.

3) That depends on it's state of charge (pic). Fully charged should be about 12.7V.

4) To actually assess the condition of a lead-acid battery it needs to be tested under load, seeing how the voltage changes with varying load currents; this can't really be done at home though. Taking the fully-charged voltage, and checking for self-discharge (multiple measurements over the course of hours) gives you a rough overview though.
http://batteryuniversity.com/learn/article/difficulties_with_testing_batteries