A power cable is a joining of two or more electrical conductors, typically held together with a sheath so that electrical power can be transmitted. Power cables are very versatile in that they can be used as permanent wiring indoors, buried underground, installed overhead or even left exposed. Equally, these cables can be put to use in portable devices, for example as audio power cables, and machinery as well as machinery and movable tools.
One important thing to appreciate, for example for hifi power cables, is that they do not transmit signals – they just carry power from the mains power supply of your home to the power supplies of your devices.
But there are some design principles which apply to all power cables, whatever they are being used for, and in whichever industry. With many types of cable, the conductors may be made from aluminium or copper, with both metals available in stranded and solid varieties, although selection may be restricted for some standards of cable.
Bear in mind that solid conductors can make it easier for connectors to be fitted, and to set the cores at terminations and joints. However, cables which have stranded conductors can sometimes be set up more easily due to their enhanced flexibility, something which is highly desirable in certain industrial settings.
When it comes to buying a power cable, your decision will probably be based on:
- Cable diameter
- Theft risk
- Flexibility of the cable
- Multi-Core or Single-Core Cable?
There are some cases where single-core cables may be the best choice, for example:
In circuits where high-load currents needs larger conductor sizes to be used, so that two multi-core cables would be needed, which gives installation problems, particularly at termination boxes.
It might also be an idea to use a single-core cable where there are small duct sizes, and where longer cable runs are required between joint bays.
However, in general terms, multi-core cables are more cost-effective and more easily installed.
These are an option where the installation environment is a tough one, and a strong level protection against impact during service is needed. These can be bought as Steel Tape and Steel Wire Armour SWA) cables, although steel wire has the advantage of being able to be drawn into an installation with a pull stocking. This grips the exterior of the oversheath and transfers the pulling tension to the SWA. Steel tape cables do not generally allow for this, since there is risk that the armour tapes could become dislocated as a result.
Finally, you should realise that a system can behave below par thanks to a poorly designed or constructed power cable, in which it is gauge of the cable that really needs to be increased.
You should find that performance between reasonably well-made power cables is broadly similar.
With more choice available than ever on today’s marketplace, it’s very easy to find the product you need and the quality you require online – what’s more, you’ll generally save money while benefitting from shopping in a time and at a place to suit you.
Juliet England is an online copywriter and blogger, specialising in writing for website such asThe Cable Company.