The Fundamentals of PAT Testing

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Briefly summarised, PAT Testing or Portable Appliance Testing begins with the examination of a portable appliance, followed next by a precise visual inspection by an individual that is competent in preforming tests,

Step 1: Observe

To start the process simple observation of the PAT testing process takes place. It is a crucial step that can’t be missed. An example situation where PAT testing is necessary would be if the company kettle were to have a cracked plug, the safety officer or office manager should be alerted

Step 2: Precise Visual Inspection

Portable appliances in the workplace should undergo the process of a precise visual inspection by a competent person. To be considered ‘competent’ person they must have some basic portable appliance testing training.

During the precise visual inspection the competent individual is required to  thoroughly inspect the portable appliance and seek out any clear defects, for example, cracked cables, frayed wires and broken plugs. The majority of the safety issues can be identified by carrying out this stage.

Step 3: Linking Inspections and PAT Testing

The final stage in the process is the hands-on inspection and testing, which is carried out at periodic intervals. All pieces of the equipment are tested in confinement, i.e. the device will be disconnected from the mains and every data cable will be removed. The person testing the device will then carry out a number of checks:

  • Assess for damage on the outer portion of the power cable.
  • Damage to the plug.
  • Check for tape on the cable.
  • Look for signs of misuse or over use, e.g. rusting.
  • Loose screws or other parts which affect the safety and working ability of the device.
  • Remove plug cover and inspect for : cord grip, adequate fuses, security and integrity, no visible bare wires, tight terminal screws and that three wires are connected to the right terminals. Additionally look for any signs of wetness, overheating and excessive amounts of dirt or dust.

Depending on the type of device, the PAT tester will then carry out a number of formal safety tests, using a specialist piece of equipment including : An Earth Bound Impedance Test, Load Test, Insulation Resistance Test and Operation Test.

When a Device Fails a Test

Minor faults may be fixed or damaged goods replaced, which allows the device to be re-tested and passed. A major fault would mean the device must be removed from the service and properly repaired or safely disposed of.

If you would like to learn more about our PAT training courses or take a look at our range of PAT Testers from leading manufacturers Megger, Seaward and Fluke, contact us on 057 866 2162 or email us here. We would be happy to answer any questions you might have.

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