It detects an imbalance in a circuit between live conductors and live. Conductors and earth, hence short circuits and earth faults,
No need to be so patronizing mate for your information I created this name in 2009 looking for help and advice about doing so, with no success but have completed my assessments anyway, this is a forum for people to get help when they need it not to get scrutinized by idiots like you
There is no such thing as a stupid question but dont go and throw your rattle out of the pram when someone points out that you are not thinking about the way the device operates