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Don't be in for a shock

23 January 2013

Jim Wallace of Seaward explains how test technology is
helping to maintain the safety of electrical appliances in
the workplace and offers some pointers on how to select
a PAT tester that is right for the job

The dang

Jim Wallace of Seaward explains how test technology is helping to maintain the safety of electrical appliances in the workplace and offers some pointers on how to select a PAT tester that is right for the job

The dangers posed by electricity and dangerous appliances in workplaces are widely recognised.

The HSE claims that nearly 25% of all reportable electrical accidents involve portable electrical equipment and reports around 1,000 workplace electrical accidents each year. Last year‚ the Electrical Safety Council estimated a total of 2.5m incidents of electric shock - of which 1.2m resulted in serious injury and 200‚000 resulted in admission to hospital.

Shocks from faulty equipment also lead to falls from ladders and scaffolds, and poor electrical installations and faulty appliances are the most serious cause of accidental fires in non-domestic premises.

With electrical safety testing remaining a priority, the need for those involved is to be able to carry out tests sensibly and efficiently without compromising the quality of testing undertaken.

Intelligent PAT testers This situation has led to increasing moves towards the use of 'intelligent' PAT testers and accessories capable of faster and more efficient testing.

The essential role of portable appliance testing (PAT) is to detect potential safety problems with electrical appliances before they occur.

To do this PAT testers range from basic pass/fail instruments to more comprehensive testers used as part of more formal preventative maintenance programmes. There are also choices to be made between battery and mains powered testers, those capable of testing either or both 110V and 230V appliances and decisions on whether or not test data needs to be recorded for transfer to PCbased records systems.

The essential tests for most electrical products are earth continuity and insulation resistance, although a host of other tests such as touch and protective conductor current, IEC cord or lead tests and RCD trip time tests may also be required depending on the type of equipment in use and the associated risk factors.

PAT test instruments are available which begin with the relatively simple to operate pass/fail checkers that carry out some of the basic safety checks on equipment and provide an immediate 'go/no go' display. These basic safety checkers do not possess an internal memory for results storage and are designed for use by those who may be relatively unskilled in electrical work - including in house test personnel.

For more comprehensive test requirements, more sophisticated mains and battery powered testers are available that combine user-friendly operation with a whole range of other features for particular test demands or routines. These include options for manual or automatic testing and the ability to record results in the tester for transfer to PC-held test management programs.

These more advanced testers also provide actual test readings for pass/fail interpretation and are therefore more suitable for use by competent electrical test personnel - typically those qualified to City and Guilds 2377.

For these applications lightweight PAT testers are now available that incorporate all Class I and Class II required electrical safety tests in a compact hand held enclosure. In the most modern PAT testers, RCD testing is now included among the test options available following advice in the third edition of the IEE Code of Practice on the testing of RCD trip times.

In the same way, the IEE Code also now recommends an insulation test voltage of 250V DC or the use of substitute or alternative leakage measurement for some types of electrical equipment - and again not all testers are equipped with the capability to undertake these tests.

The incorporation of Bluetooth technology in some advanced PAT testers allows the wireless connection of bar code scanners, label printers and other accessories - allowing totally cable-free testing, without the cumbersome and constant plugging in and unplugging of leads and cords.

Automatic record update The use of computerised portable appliance testers also enables data to be transferred directly from the instrument to a PC-stored database allowing an automatic update of test records, the generation of test reports and advance testing schedules. For testers that do not possess an internal results memory, manual entry software programs enable test records to be updated.

With the variety of PAT testers available, dutyholders have a range of options to ensure the safety of electrical equipment used in all workplaces and meet their obligations to provide a safe environment for staff and the public.