Regardless of whether you are an electrical installer, verifier or inspector, collecting accurate and consistent results from testing is an imperative.
But in order to comply with electrical industry standards and regulations, you’ll need to use the right instruments according to the relevant parts. Alternative equipment can be used, but this must provide an equivalent level of performance, which should also comply with legal safety requirements.
With this in mind, here is an Instrotech guide to test equipment and what they can be used for. They also have a wide selection of electrical testers online, and run specialist training courses on subjects like PAT testing as well as thermography.
Test equipment
When carrying out low voltage installation verification and condition reporting work, electrical contractors and installers will need to have the right test instruments and equipment available in their toolkits. As a minimum, these should include the following:
- Continuity test instrument
- Insulation resistance test instrument
- Loop impedance test instrument
- Residual current device test instrument
- Voltage indicating instrument with a suitable proving device
- Suitable split test leads for both the loop impedance test instrument and the residual current device test instrument
- MCB lock off kit
An earth electrode resistance test instrument is also desirable, but an earth fault loop impedance test instrument may also be used. Although there is no alternative for confirming the accuracy of an earth electrode resistance test instrument apart from calibration, a test box can be constructed for this purpose.
For greater practicality, you can now find single instruments cable of performing two or more functions of the aforementioned equipment too. This has made life for the modern day electrician a lot simpler than before but it is still of vital importance to have the right product available for any job.
Choosing and using test equipment
All test instruments will come with specific manufacturers operational instructions including which standard the product conforms to. If you use the wrong equipment with the wrong voltage, you could be putting yourself and others at risk. So, before conducting any test, make sure your choice of instrument is correct.
- BS EN 61557 – This is entitled “electrical safety in low voltage distribution systems up to 1000 V AC and 1500 V DC. Equipment for testing, measuring or monitoring of protective measures.” A number of parts make up this standard, which includes general requirements, insulation resistance, loop impedance, resistance of earth connection and equipotential bonding, resistance to earth, effectiveness of residual current devices (RCD) in TT, TN and IT systems, phase sequence, and insulation monitoring devices for IT systems.
- BS EN 61010 – This is entitled “safety requirements for electrical equipment for measurement control and laboratory use,” which is the basic safety standard for electrical test instruments. BS EN 61557 also requires compliance with this standard.
- BS EN 61243-3 – This is entitled “live working – voltage detectors – two-pole low voltage type,” which all voltage detection instruments should also conform to.
For information on electrical testing standards, visit the Health and Safety Executive website as linked to above. Alternatively, contact Instrotech to discover more about what test instruments are available and when they should be used. Even if you already own testing instruments and equipment, they may not be fit for purpose and it is always better to be safe than sorry.
