Glossary of electrical jargon

Consumer unit

The more common name for fuseboard or fusebox, means exactly the same though.

L.E.D
Light Emitting Diode, A new form of intense, low energy lighting and bulbs, that cost less to run, generate far less heat and look great.

P.I.R
Passive Infra Red, a sensor that will pick up heat traces, generally used for security lighting at night to turn lights on.

Photocell
Commonly refered to as dusk to dawn sensors, they do just that, turning on items at a pre-determined lux eg, dusk and off again when it becomes brighter, eg, dawn.

Lux
The measurement of light, all items of lighting have a lux rating, to determine whether they will be bright enough for the intended use.

M.C.B
Miniature Circuit Breaker, replaces old style wire fuses with a trip switch that can be reset following a fault, easier to use, far less dangerous and cheaper in the long run. All consumer units should have mcb’s instead of fuses, it makes my life much easier....and yours cheaper.

Transformer
A unit designed to transform from a higher voltage to a lower one, eg, when used in downlighters, converts from 230v to 12v.

R.C.D
Residual Current Device. Like an mcb but senses earth faults, shutting off circuits in the event of an earth fault. Commonly used in outside power applications, socket circuits and garages.

Spur
A slang name for a fused switch that normally controls an appliance, eg fridge, freezer, dishwasher. Also can refer to an extension to an existing circuit eg, an extra socket on a socket ring.

Chasing
Cutting into a wall to sink cables or boxes so that they sit flush with the surface. This requires making good afterwards, usually not carried out by the electrician.

Ring Circuit
Normally refers to how sockets are wired in most domestic properties. A ring circuit has no end, so from the consumer unit the circuit will go to each socket in turn, then back to the consumer unit.

Armoured
A steel sheathed cable normally used for external power applications, eg garage/shed supply or for outside lighting. Its very difficult to cut through, therefore decreases the likelyhood of it being cut through accidently.