Electrical equipment is one of the most common causes of workplace fires and this is frequently due to a faulty or damaged appliance. Workplace health and safety legislation requires all employers to carry out regular testing on all portable electrical appliances, and to ensure that they are maintained in safe working order.
Whether you buy in the services of a specialist contractor or train your own staff to do your PAT testing in-house will depend on the nature of your workplace and size of your business. Testing courses are normally only a single day, and you can purchase PAT testing equipment very easily. However, there are several different types of PAT tester out there, and you should consider which type is best going to suit your needs before you purchase. This article is intended to help you narrow down your search to find the most appropriate PAT testing equipment.
Pass/Fail Type Equipment
Starting at the beginning, the Pass/Fail sort of devices are the simplest and most basic models, giving only a straight pass or fail result and no further detail. PAT testing equipment can be designed to carry out various different tests, but the pass/fail type tend to only do the insulation and earth continuity tests. They are unlikely to offer the selectable earth continuity test current, which is an important point, as this can be a problem unless you only have a very limited number and type of appliances to test.
The difficulty with PAT testing equipment without a variable current are limited in the equipment they can test reliably. Equipment with a higher current should not be used on IT equipment and testers with a fixed low current are not reliable for testing general electrical appliances. If you need to PAT test a range of different types of appliances accurately you will therefore need to have a selectable current function.
Another restriction with pass/fail PAT testing equipment is that they will have a fixed earth bond pass limit, which does not allow any adjustment. The problem with this is that it can result in some equipment failing the test, simply because they have very long leads, rather than because anything is wrong with them. While it may be tempting to increase the limit to compensate for this, doing so would actually contravene the IEE (Institute of Electrical Engineers) Code of Practice and perfectly good appliances may still not pass.
Manual Testing Equipment
Manual PAT testing equipment has greater functionality than the simple pass/fail type, which can overcome the problems highlighted above. These increased functions and the greater detail and variability do, however, mean that the testers are a bit more complicated, so anyone using them would require a more in depth knowledge in order to fully utilise and understand them. There is therefore an implication for staff training. The selectable earth continuity test current in this type of device makes them suitable for testing IT equipment.
Downloadable Pat Testers
Downloadable PAT testing equipment automates the testing process and stores the results so that they can be printed off or downloaded to a computer. This function can be a great advantage if your premises are particularly large or complicated. These testers can also have other functionality covering all sorts of things, some of which may be of more use than others, depending on your situation.
One function worth looking for is the ability to take true earth bond measurements. This is a feature that can save your testers time, and therefore cost you less. Carrying out earth bond measurements on appliances that have multiple earth paths (on a PC for example) cannot be done without disconnecting it from all other equipment first, unless your PAT tester has this function. That can add a lot of time and money if you have a significant amount of IT equipment to test.