These instruments all perform substantially the same tests, but are available all the way from basic manual devices up to computerised machines with asset tagging and label printing. A competent electrical engineer with a well-stocked bench could probably create a set-up to perform the electrical tests themselves, but for convenience and calibration they are invariably combined together in an application-specific self-contained unit, the PAT tester. The PAT test has several parts, of which some are physical and some are electrical. Join me after the break for an overview of the PAT system. Thus “Portable Appliance Testing”, or PAT, is how the process is usually referred to. It doesn’t specify how this should be done, but the way this is usually achieved is by a set of electrical tests whose official name: “In-service Inspection & Testing of Electrical Equipment”, isn’t very catchy. In the United Kingdom,where this piece is being written, the law in question is the Electricity At Work Regulations 1989, which specifies the maintenance of electrical safety and that there should be evidence of regular maintenance of electrical appliances. Under those regulations, all appliances must be regularly tested, and any appliances that fail the tests must be either repaired or taken out of service In most countries there are electrical regulations which impose some level of electrical safety on commercial premises.
How often have you seen a plug held together with electrical tape, or a cord with some of its outer sheath missing? It’s something that we shouldn’t do, but it’s likely many readers are guiltily shuffling a particular piece of equipment out of the way at the moment. Of course, we’ve all had appliances that have become damaged. We don’t give our electrical devices a second thought, but in addition to their primary purpose they all perform the function of keeping us safe from the dangerous mains voltages delivered from our wall sockets. Everywhere we look in our everyday lives, from our bench to our bedroom, there are the ubiquitous electrical cords of mains-powered appliances.