Wednesday, 20 August 2014

Finding an Earth Point on an appliance when doing a Class I test


One difficulty one faces when carrying out a Class I test is where to connect the test lead to. Newcomers to PAT testing can spend time finding a suitable earth point or worse still fail appliances that should pass. This blog advices on suitable earth points on a number of common appliances.

Examples of earth test point



Earth point on fridge


Earth point on sandwich toaster



Earth point on iron



Earth point on electric fan


Earth point on PC


Earth point on microwave oven


Earth point on printer



Earth point on monitor 



Earth point on a 110V transformer


Earth point on a toaster


Earth point on a kettle


Why do we need to connect to an earth test point?

In order to measure the Earth Continuity we need to pass a current through the Earth lead of the appliance and back to the tester. The diagram below shows how this is done for a kettle.




In summary when testing Class I appliances it's vital to measure Earth Continuity. In order to do this the test clip must be connected to a suitable (metal) earth point on the appliance.




















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