skip to Main Content

Electricians in Sheffield

Firstly, whether your house is being rewired or you’re having new sockets fitted, it will help to know the difference between a consumer unit and a circuit breaker. Therefore, our Electricians in Sheffield have put together a jargon-buster to explain below some of the more common terms used.

A-Z of Carbon Jargon

An A to Z of the key terms linked to carbon-related issues as well as terms commonly used by those working towards a sustainable built environment. Designed by or Electricians in Sheffield.

Click here to download the pdf.

BS – British Standard

British Standard BS 7671 also known as the IEE (Institute of Electrical Engineering) wiring regulations. Details the requirements for electrical installations and is the standard against which all NICEIC contractors are assessed. To enrol with NICEIC all electricians, and anyone they employ, must meet this national safety standard.


An assembly of electrical equipment (socket outlets, lighting points and switches) supplied from the same origin and protected against over current by the same protective device(s).

Circuit-breaker or RCD

According to Electricians in Sheffield, it is a device capable of making, carrying and breaking normal load currents and also making and automatically breaking, under pre-determined conditions, abnormal currents such as short-circuit currents.

Class I equipment

Equipment in which protection against electric shock does not rely on basic insulation only, but which includes means for the connection of exposed-conductive-parts to a protective conductor in the fixed wiring of the installation.

Class II equipment

Such as music systems and televisions.

Class III equipment

Equipment that is protected against electric shock relies on supply at SELV (Safety extra low voltage).

Consumer unit

Also known as a fusebox, consumer control unit or electricity control unit. A particular type of distribution board comprising a co-ordinated assembly for the control and distribution of electrical energy, principally in domestic premises, incorporating manual means of double-pole isolation on the incoming circuit(s) and an assembly of one or more fuses, circuit-breakers, residual current operated devices or signalling and other devices purposely manufactured for such use.

Distribution board

An assembly containing switching or protective devices (e.g. fuses, circuit-breakers, residual current operated devices) associated with one or more outgoing circuits fed from one or more incoming circuits, together with terminals for the neutral and protective circuit conductors. It may also include signalling and other control devices.

Electrical installation

Any assembly of electrical equipment supplied by a common source to fulfill a specific purpose.

Extension leads

An extension cable, also known as a power extender, extension cord or an extension lead, is a length of flexible electrical power cable or flex with a plug on one end and one or more sockets on the other end – usually of the same type as the plug. However use of extension leads should be avoided where possible, as there is a chance of overloading the circuit.


Low Voltage


Milliamp or 1/1000 part of an amp


Electrical current (in amps) that exceeds the maximum limit of a circuit. May result in risk of fire or shock from insulation damaged from heat generated by overcurrent condition.

Part P

The specific section of the Building Regulations for England and Wales that relates to electrical installations in domestic properties.

PAT – Portable Appliance Testing

Inspection and testing of electrical equipment including portable appliances, movable equipment, hand held appliances, stationary equipment, fixed equipment/appliances, IT equipment and extension leads.

PIR – Periodic Inspection Report

An electrical survey, known as a Periodic Inspection Report (PIR). The cost of a typical PIR should start around �100, depending on the size of your property. The report will establish the overall condition of all the electrics and state whether it is satisfactory for continued use, and should detail any work that might need to be done.

PLI – Public Liability Insurance

Broad term for insurance which covers liability exposures for individuals and business owners. It will also cover them if they damage your property while on business. The cover should include any legal fees and expenses which result from any claim by you. Homeowners looking to employ trades people to undertake work on their homes should ensure the companies selected have suitable cover � minimum recommendation is �2 million.

Portable equipment

Items that can be moved from one place to another like as a toaster.

Prospective fault current

The value of over current at a given point in a circuit resulting from a fault between live conductors.

RCD – Residual current device

Residual current device is a safety device that switches off the electricity automatically when it detects an earth fault, providing protection against electric shock.

RCD – residual current device

This is not just a manually operated isolating switch, but a very sensitive safety device which cuts off in fractions of a second if it senses an earth fault. However, RCDs can be bought in different current ratings and various sensitivities to current leakage.

Ring final circuit/ring main/ ring

A final circuit connected in the form of a ring and connected to a single point of supply.


Separated Extra-Low Voltage.

Voltage, extra-low

Normally not exceeding 50 V a.c. or 120 V ripple-free d.c., whether between conductors or to earth.

Finally, if you have any questions contact us to speak to one of or Electricians in Sheffield.

Back To Top