Portable Appliance Testing
The full advertised word for PAT testing is “Portable Appliance Testing”, but it is known as PAT testing. PAT testing is a process by which electrical appliances are routinely checked for safety. The test involves a series of inspections and electrical tests on each item. The PAT test varies depending on the class of the item. Class I has a single insulated wiring, which requires an earth connection.
There is no symbol for a Class I product so if a rating plate has no symbol on it then it is usually Class I. Class II has a double insulated wiring, therefore no need for an earth lead. Class II is indicated by double box. Class III – These are appliances that are supplied at a low voltage (usually called Separated Extra Low Voltage) which must be less than 50 V.