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Electrician in Sheffield


This page is intended to explain some of the less obvious terms and phrases used in the electrical profession, if you have any questions please contact us.

Part P - A section of the building regulations that requires most domestic electrical work to be certified and also notified to the local authorities, this should be done on your behalf by any reputable electrician - always ask for a certificate and for larger jobs eg. new circuits or a new board expect a letter of notification from your local authority that the work has been completed.

Consumer unit - Also known as the fuse box, this is the box (normally in the cellar or a cupboard near to your meter) where the fuses or circuit breakers are.

MCB - Miniature circuit breaker, these are the switches (or fuses) protecting each circuit.

RCD - Residual current device, this is a safety device covering some or all of the circuits in your home, it monitors your system and will disconnect all the circuits it covers if it detects a fault.

Earth Bonding. This is the yellow and green cable, which connects your incoming services (water, gas, etc) to the earth block to ensure the metal pipework has the same electrical potential (An electric shock can only occur if there is variation in potential) .

Supplementary Bonding. The yellow and green cable, which is sometimes used to connect exposed metalwork and/or electrical fittings such as boiler pipes or metal bathroom fittings together. See earth bonding above.

3 Phase. A type of supply used for heavy machinery, and not normally available to domestic customers (which usually have a single phase supply).

PAT testing. Portable appliances (almost anything with a plug) in the work place should be tested at regular intervals and marked with a sticker to show they are safe.

Ring circuit. This is a common way to wire sockets. A supply is taken to the first electrical point, (usually sockets) then each point should be linked to the next and finally back to the point of supply (normally the consumer unit). Additional sockets taken from the ring are called spurs.

Spur. An additional socket added to a ring circuit.

Radial. A way of wiring electrical points which, unlike a ring circuit does not return to the point of supply.

Surface mounted. Sometimes the sockets and switches are fixed to a plastic or metal backbox rather than buried in the brickwork, this often means a quicker, and therefore cheaper job with a lot less mess.

Flush fitting. This means that switches or sockets are fixed into the plaster or brickwork. It's a better job when finished but may require some plastering and/or redecorating.

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