It's not for measuring current and it's just DC voltage 12-24v, basically you connect the terminals to the battery and then you can press a button this will then supply a positive or negative supply to the circuit under test depending which way you press it, The power probe has a rest able trip which is preset say 10amps dangerous if there is a short or something and the circuit could only handle 2-3amps or if you pressed the button to go negative with the probe tip connected to a positive supply, The power probe hook has a electronic rest able trip which can be set from 0-65amps (100amps peak), Here is the link to it.
http://www.powerprobe.com/webstore/index.php?route=product/product&product_id=50My idea is use the Arduino to display all the data like amps drawn (internal shunt) voltage and have buttons to set the max current so if it detects a short/excess current draw it removes the power fro the tip instantly to prevent any damage. Powered from the battery/power of the circuit under test or even it's own battery
hope this makes it clearer and makes more sense