Various Types of Portable Appliance Tests

We live and work in a world full of electrical gadgets. A range of appliances can be found in our homes, businesses, and manufacturing sites. However, electricity is hazardous to life. A little oversight can have severe consequences. As an electrical appliance operator, the Portable Appliance Testing course allows you to understand how appliance testing fits into an overall electrical safety program.

A few PAT tests that should not be overlooked are:

Earth continuity tests

This test is performed on all Class I appliances to check that there is an acceptable connection between the Earth pin in a socket and the case of the device. When performing an earth test, the appliance is plugged into the PAT Testing machine, and the machine's earth bond lead is clipped to an exposed metal component of the EUT. The PAT machine then sends a current around the newly formed circuit. Two forms of earth bond test current are commonly employed. Low test currents are often in the 100 to 200 milliamp range, whereas large test currents are in the 10 amp to 25 amp range. A good connection is one with a resistance of fewer than 0.1 ohms.

Insulation resistance testing 

The insulation resistance test verifies that the insulation that surrounds the live parts of an appliance has a sufficient level of resistance. During PAT Testing, this test is performed on Class I and Class II appliances. All PAT testers that do this test do so by internally shorting the live and neutral pins. Adequate insulation is defined as more than one million ohms for Class I appliances and two million ohms for Class II appliances.

Load testing

The load test determines the power consumption of the equipment while it is in operation. An appliance can be automatically assessed for excessive load by specifying a load VA limit. The portable appliance tester applies the supply voltage to the under-test equipment and measures the power consumption in kVA. The findings of this test can be an excellent analysis of future difficulties and potential appliance failures.

Current leak testing

The leakage current test checks if any current is going to earth by measuring the difference in current between the live and neutral conductors. This test is performed on both classes I and II. The test calculates and shows the leakage current that would flow to verify that the equipment remains safe even when the main supply is raised to its maximum allowable value. The result of earth leakage current should be zero or extremely low in most equipment.

Functionality check

If you discover damaged or faulty equipment, it should be labeled. Whereas, if it is harmful, it should be removed from service and brought to the attention. The operator must decide if the equipment is appropriate to be used. If the individual determines that it is unsuitable for either of these reasons, it must be replaced with more appropriate equipment.

Read More: Benefits of Electrical Training in Terms of Your Career

Flash Testing

When high test voltages are delivered to an asset, flash testing determines the leakage current. The flash test generates a high alternating current test voltage of 2500 V or 3000 V and the leakage current is then monitored. This test can be destructive and is normally reserved for repaired equipment. It is not commonly used for electrical equipment "in-service testing."

Final Thoughts

Portable Appliance Testing (PAT) is a well-known and widely used method of hazard prevention. A thorough PAT testing comprises a visual inspection, extensive equipment checks, and several appliance tests using a PAT testing gear. Identifying flaws with various portable appliance tests can help to ensure the safety of electrical equipment.