This test is performed on Class I and also Class II appliances during Pat testing. The objective of this test is to make certain that there is adequate insulation in between the Live parts of the home appliances as well as the user touchable metal parts. Appropriate insulation is specified as above 1 M ohm for Class I appliances and 2 M ohm for Course II appliances.
PAT Testing a Class I appliance
Connect the home appliance right into a Pat Tester. Make sure that the appliance is activated. When the test is done if there is more than 1 M ohm resistance between the Live + Neutral as well as the Earth pins of the plug, after that there suffices insulation and the home appliance is thought about risk-free.
PAT Testing a Class II home appliance
Connect the appliance right into a PAT Tester. Ensure that the appliance is activated. Link the test probe to any type of metal component on the home appliance. For example on a drill, this would be the chuck.
When the test is done, if there is greater than 2 M ohm in between the Live + Neutral and any type of metal part after that there suffices insulation and also the device is thought about risk-free.
Note that it is crucial to connect the test probe to all metal parts on the Course II appliance consequently. This might need several tests. If this is refrained from doing after that any problems with the insulation will certainly not be detected throughout PAT testing.
When executing this test there are a variety of functional things to consider.
PAT Testing – Test Voltage
This is usually carried out by making use of a voltage of 500V. Nonetheless, surge safeguarded home appliances have components that present a reduced resistance at this test voltage. When accomplishing the Insulation Resistance test throughout PAT Testing, if one obtains a failure on surge-protected home appliances, it is normal to repeat the test at a lower 250V. For instance, the Kewtech tester has this facility.
If the PAT tester does not have a 250V test option after that is adequate to make a note regarding this as well as pass the rise shielded device.
The PAT tester does the insulation Resistance Test at a voltage of 350V as well as will certainly PASS surge protected devices.
PAT Testing – Heating as well as Cooking Appliances
In some appliances making use of mineral insulated heating elements, taken in dampness might lead to a failure when this test is accomplished during PAT Testing. In this instance, turn on the appliance for a duration to drive off excess dampness and after that retest.