Jargon Buster

AC (alternating current) - an electric current which periodically reverses direction

Anif – A plastic enclosure with window access to protection

Ampere (amp) - the base unit of electric current in the International System of Units. Defined as measuring the electromagnetic force between electrical conductors carrying electric current.

Arc Flash - the light and heat produced as part of an arc fault, a type of electrical explosion or discharge that results from a low-impedance connection through air to ground or another voltage phase in an electrical system.

Arctic cable – A grade of cable made to BS6004

Auto transfer switch – Used to switch from normal to emergency power in power failure

Auto transformer starter – Used to reduce voltage applied to electric motor during starting

Backup protection – Intended to operate in case of power failure.

Base load – The portion of load which is constant

Base plates – see mounting plate

Brown out - brownout comes from the dimming experienced by incandescent lighting when the voltage sags. A voltage reduction may be an effect of disruption of an electrical grid, or may occasionally be imposed in an effort to reduce load and prevent a power outage, known as a blackout.

Busbar - a busbar (also bus bar) is a metallic strip or bar, typically housed inside switchgear and panel boards for local high current power distribution.

CE Marking - the abbreviation of French phrase "Conformité Européene" which literally means "European Conformity".  By placing the CE marking on a product a manufacturer is declaring conformity with all of the legal requirements to achieve CE marking.

CEE-form – refers to industrial plugs and connectors that are made to IEC 60309 and various standards based on it (including BS 4343 and BS EN 60309-2)

Circuit - A path in which electrons form a voltage or current source flow.

Circuit Breaker - an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit.

Connector – Another name for an industrial socket

Contactor – Electrically operated heavy current switching device. Unlike a circuit breaker not intended to interrupt current fault.

Container – Usually taken to refer to an ISO Shipping container

Cycle – the complete reversal of an alternating current from zero to maximum and back

DC (direct current) - an electric current which flows only in one direction. 

Dielectric Strength - the maximum electric field that a pure material can withstand under ideal conditions without breaking down

Directive (European) - A directive is a legal act of the European Union which requires member states to achieve a particular result without dictating the means of achieving that result.

Distro – An electrical distribution box, usually mobile.

Earth Fault - An open-circuit fault occurs if a circuit is interrupted by some failure. In three-phase systems, a fault may involve one or more phases and ground, or may occur only between phases. In a "ground fault" or "earth fault", current flows into the earth.

Enclosure – A general term but often a protective casing for electrical distribution

E-stop – Emergency stop (push button)

Euronorm – European standards which must be transposed into member states standards.

Event distribution – Usually portable, rubber or plastic enclosed electrical distribution units.

Festoon – a string of lights, usually hung in a curve, on flexible cable for decoration / site lighting

Field – A permanent or electromagnet whose magnetic field induces voltage.

Fire rated enclosure – An enclosure constructed to meet fire regulation i.e. BS476 4 hour fire rating.

Flange - a projecting flat rim, collar, or rib on an object, serving for strengthening or attachment

Fixing Centre – This refers to the dimensions of the screw points where the object will be attached.

Frequency – Number of cycles of an alternating current or sound wave in a given time i.e. Hz or cycles per second

Gang - a set of switches, sockets, or other electrical or mechanical devices grouped together.

H07 Cable - heavy-duty rubber flexible rating of 450/750V designed to provide high flexibility and to withstand chemical, mechanical and thermal stresses.

IK Code - international numeric classification for the degrees of protection provided by enclosures for electrical equipment against external mechanical impacts.

Independent distribution network operator - (IDNOs) develop, operate and maintain local electricity distribution networks.

Industrial Adaptors – used to split power in the same ampage or to switch from ampage to another

Impedance - the effective resistance of an electric circuit or component to alternating current, arising from the combined effects of ohmic resistance and reactance.

Insulation - a material whose internal electric charges do not flow freely; very little electric current will flow through it under the influence of an electric field.

Imst – a plastic electrical distribution unit

IP Rating - used to define levels of sealing effectiveness of electrical enclosures against intrusion from foreign bodies (tools, dirt etc) and moisture.

Kilo-volt-ampere (k)VA - a unit of apparent power, which is electrical power unit. 1 kilo-volt-ampere is equal to 1000 volt-ampere: 1kVA = 1000VA.

Kilo-volt-ampere reactive (kVAr) - a unit of reactive power. Actual Power consumed by loads is called Kilo Watt Power. All the Power given to the load is not utilized as useful power, some power is being wasted. The power which is not consumed is called Reactive power i.e kVAr.

Kilo-watt (kW) – is 1,000 watts, which is a measure of power.

Kilo-watt-hour - is a unit of energy equal to 3.6 megajoules.

LED – Light emitting diode, an electronic device that emits light when an electrical current is passed through it.

M-Box – plastic enclosure with window for electrical distribution

Main Breaker - the breaker that controls the power to the entire box

Make before break - a configuration in which the new connection path is established before the previous contacts are opened. This prevents the switched path from ever seeing an open circuit.

MCB – Miniature circuit breaker, a small trip switch operated by an overload and used to protect an electric circuit

MCCB – Moulded case circuit breaker, has a rugged construction as it can break larger currents usually from (100-1000A)

Meg-ohm – a unit used in defining the level of insulation in terms of its resistance to current leakage

Merz – a plastic distribution unit used for portable electronic distribution

Midnight (PCE) – refers to the range of all black coloured products from PCE

Normally closed / open contact – description of the status of a relay contact when the relay is de-energised.

Notified Body - an organisation designated by an EU country to assess the conformity of certain products before being placed on the market.

Ohm - the SI derived unit of electrical resistance, named after German physicist Georg Simon Ohm.

Overload - occurs when too much current passes through electric wires.

Panel Mount (straight) – a flanged plug or connector for mounting to the surface of a unit

Panel Mount (angled) – as above with angled entry

PCE – Austrian supplier of plugs and connectors

PLC Controls – programmable logic controller, an industrial digital computer which has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, or robotic devices,

Plug (trailing) – An industrial plug with cable entry

Power tool transformer – transformer for intermittent use

Pole – the number of contacts on a contactor or circuit breaker

Reactance - the opposition of a circuit element to a change in current or voltage, due to that element's inductance or capacitance.

Real time clock -  a computer clock that keeps track of the current time.

Safety integrity level -  a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction.

Salzburg enclosure – Wall mounted electrical distribution enclosure

Shunt trip - an optional accessory in a circuit breaker that mechanically trips the breaker when power is applied to the shunt trip terminals.

Single Phase - the distribution of alternating current electric power using a system in which all the voltages of the supply vary in unison.

Site distribution – Usually portable, metal enclosed electrical distribution units

Site transformer – Transformer for constant use.

Sky Hooks – a plastic hook used for hanging things such as festoon

Steyregg - An electrical distribution enclosure

Solid state - refers to electronic components, devices, and systems based entirely on the semiconductor 

Starting current – High current drawn by an electric motor during starting

Surge - a transient wave of voltage, current or power in an electrical circuit. This is usually a sub-cycle overvoltage lasting less than a half-cycle of the regular voltage waveform and can either be additive or subtractive with positive or negative polarity.

T-Box – Thermoplastic distribution enclosure

Transformer - a static electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. 

Unrestricted earth fault protection – Protection where a current transformer is fitted in the neutral connection to earth. Protection will operate for any earth fault in the network. Thus it is “unrestricted”.

Vacuum circuit breaker - a kind of circuit breaker where the arc quenching takes place in a vacuum medium.

Varistor - an electronic component with an electrical resistance that varies with the applied voltage.

Vibration Mounts – Used to decrease vibration within an enclosure

Volt – The unit for electrical potential

Wall Socket – A socket with a wall mounting enclosure