The definition of twin and earth cable – also known as T&E – is a flexible flat covered mains electricity wiring cable. It comprises of two individually insulated current-carrying conductors – and an uninsulated circuit protective conductor.
What is twin and earth cable used for? This is the most common cable used for domestic wiring – see more details below…
Twin and Earth Electrical Cable Overview
Fixed wiring cables are appropriate for residential, commercial, and industrial settings. Twin and earth cable is suitable for installing in fixed wire installations such as power supply cables for sockets and switches, and light furnishings. Other uses include smoke alarm installation and central heating thermostat fittings.
Twin and earth cable sizes come in standard metric options. These are:
- 1mm twin and earth, 1.5mm, and 2.5mm which have non-stranded conductors
- 4mm, 6mm, 10mm, 16mm and higher which have stranded conductors
An electrical conductor has the capacity to transmit electricity. In electrical systems all conductors comprise of solid metals moulded into wires – copper, gold, silver, and brass are all good conductors. Copper wire is commonly used in electrical wire to conduct electricity, and silver is the best conductor of electricity as it contains a higher number of moveable atoms known as free electrons.
Other twin and earth cables
- Low Smoke and Fume cables (LSF)
- Low Smoke Zero Halogen cable (LSOH)
- Zero Halogen Low Smoke Cable (OHLS)
These cables are designed to minimise the release of poisonous fumes when subjected to burning or fire – reducing smoke and toxic gases in an emergency situation.
Ratings for Twin and Earth Electrical Cables
Twin and earth cable ratings are measured in amps. And figures shown are calculated with the cable being surrounded by thermal insulation and not touching the wall. For example, the current-carrying capacity of 2.5mm twin and earth cable is 20 to 23 amps. These figures may vary depending on the quality of the cabling.
Electrical Cable Size Rating in Amps
- 1mm up to 13
- 1.5mm 14 to 16.5
- 2.5mm 20 to 23
- 4mm 26 to 32
- 6mm 32 to 38
- 10mm 44 to 52
- 16mm 57 to 69
More Twin and Earth Cable Data
The harmonised colours for this type of cabling comprises of brown sleeving for the live core, and a blue sleeving for the neutral core. The earth core will be in a green and yellow sleeving.
1mm and 1.5 mm cabling can be used for lighting circuits. A lighting circuit can serve up to 12 x 100W light bulbs. Bear in mind that 1mm cabling should only be used for a maximum length of 95 metres of a circuit – not including the light switches.
You can buy a 2.5 twin and earth in 100m lengths to use internally in channels, embedded in plaster, or on boards or trays. The PVC sheath allows for quick and easy installation – and the cable will withstand mechanical stress, so is ideal for domestic and commercial circuit wiring. 2.5mm twin and earth cable is commonly used behind sockets.
4mm twin and earth rating is up to 32 amps. The cores of this cable are insulated with PVC and the interior is of copper wires. The outer sheath is typically grey in colour. The 43mm twin and earth cable have the same colour components as described above – and the conductors are stranded. This cabling isn’t suitable for outdoor use as the outer sheath is susceptible to damage from direct sunlight.
6mm cabling is generally used in buildings for housing and electrical wiring. Conductors are normally of copper or aluminium. Copper has the advantages of anti-oxidation, anti-corrosion, and can bear a higher temperature making it more fire-resistant
10mm cabling options cover the main bond between the consumer unit to incoming water, gas, and oil service pipes. And 16mm cabling is designed primarily for domestic electricity mains.
Get Professional Help and Advice
When you need assistance with any electrical wiring issues you need to contact your local 24-hour electrician. You’ll make an appointment with an expert registered with the National Inspection Council for Electrical Installation Contracting, so you know you’re in safe hands.
With years of industry experience, your electrician will swiftly diagnose any faults on your domestic or commercial property – and where necessary will carry out any re-wiring, of fit new plugs and sockets to make your current system safe.
