Most modern homes are fitted with at least one RCD (Residual Current Device) or GFI (Ground Fault Interrupter). These are one of the greatest electrical safety inventions in history, but when they start tripping randomly it can be a real nuisance to try and hunt down the cause.
This is where a good sensitive AC current leakage detector can be very useful. In this case I'm using an AMECaL ST-9810 which is a nice simple clamp meter with peak hold that can measure current down to 100uA. It's optimised for tracking down earth leakage current, but also functions as a regular clamp meter too, with a current measuring range up to 200A.
In this video I show the use of an in-line adaptor that allows you to break out the live and neutral conductors separate from the earth for an appliance. It's simply a very short extension with the earth core gently pulled out of the flex and wired external to it. If making one of these I'd recommend that the live and neutral cores are sleeved for protection, particularly if it's going to be rattling around in a tool box or van.
This video also explains how an RCD works and why they aren't infallible and as such should not be used as an alternative to safe electrical practices.
A link to Amecal's website (UK based company) http://www.amecal.com/