At LJ Electrical, we specialise in providing electrical maintenance services for commercial, residential and industrial buildings. Today we’re going to provide a cable testing guide, so you can have some basic information about how to test cables and what we do as part of our cable testing services.
Colour Codes and Electrical Wires
Although you should use a professional service for cable testing, understanding what each coloured wire is in your electrical cables is a useful skill that everyone should know. Although taught at schools, this information is often forgotten. It is especially when testing if wires are live or not. Learning more in the electrical field and having a better understanding of how your cables work is useful for daily living. The system will either be multiphase or single phase. Residential properties usually have a single-phase system installed which is electrically connected at 230 – 240 volts, whilst commercial and industrial areas will use multiphase systems with the electricity connected at 400 – 415 volts.
The colours for residential properties are as follows:
Active – Red
Neutral – Black
Earth – Green/Yellow
Here are multiphase systems and their colouring:
Phase 1 – Red
Phase 2 – White
Earth – Green/Yellow
Phase 3 – Dark Blue
When Cable Tests are Required
Whenever there is work performed near or on electrical systems, an electrical wire should be tested. To test if the wires are live should be relevantly straightforward. However, it is important that such tests are completed safely and carefully. We are here to offer guidance when individuals want to test for live wires, although we recommend you get in touch with details before any attempts as our services may be needed in person.
How to Check if Wires are Live
All commercial, residential and industrial buildings legally follow the wiring regulations set by the British Standard BS 7671. These standards include the safety requirements for new technologies, installations and more. When it comes to electrical wiring, rules include details on the wiring colours and ascertain that all the wires in the building are consistent. When testing if electrical wires are live, it is vital to know the colour code of the wires and the premise. If you are attempting to work on wires, only working with the red or active wire is safe for those untrained in electrical work. The power must be turned off to avoid any electrical dangers from occurring. The Earth wire should be connected at all times as this offers you protection from electrical surges.
How to Test Cables
The testing of cables for a live electrical wire requires either a non-contact voltage tester or a digital multi-metre. A non-contact voltage tester is the safest way for testing live wires and is performed by placing the machine near the wire. When it comes to digital multi-metres, the two probes are affixed to the cable. This can check for resistance, amps and voltage. Again, the power should always be turned off when working with electricity.
Whether in a domestic setting, commercial or industrial, electrical safety is paramount to looking after your overall safety and wellbeing. To find out more about whether you are at risk with faulty electrics or appliances, please get in touch with LJ Electrical through our online contact form or by calling us on either 01509 266383 or 07770 788469. Based in Loughborough in Leicestershire, we will be happy to provide you with more information and answer any questions you may have for us.