When trying to pat test computers, I always get a fail on the earth leakage test.

Pre 5th Edition versions of the PrimeTest 100 has a set pass/fail value of 0.75mA so any reading exceeding this will indicate a fail. One of the changes made in the 5th Edition Code of Practice was the increase in leakage limits to 5mA, so if your reading is 5mA or less than you can log this as a pass in your records.

5th Edition compliant PrimeTest 100's (signified by the 5th Edition logo on the front of the tester) will now read leakage tests up to 5mA and pass/fail the test accordingly.