Acronyms for the electrically challenged

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Jul 10, 2009
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As a non professional Sparky but with more than a passing interest, I am really enjoying these forums. One thing that I do find a bit of an issue is all the Acronyms - some of which are industry specific and some of which are just "short for" on the board. Not being one to complain and do nothing about it I thought I would start a list.

This is designed to be explanatory rather than technically comprehensive or exact. There are bits missing and vague that I hope people will add to and correct. Otherwise hope someone find it useful.

AC - Alternating Current Normal household electricity

AFAIK / AFAIAC - As far as I know / As far as I am concerned.

BC - Building Control

BCO - Building Control Officer

BRB - big red book (17th edition guidance)

BS7671 - This is the current wiring regulations now 2008 and commonly known as the 17th edition.

BTW - By the way

C&G - City and Guilds

ccts - circuits or certificates

CCU - Cooker Connection Unit

CPC - circuit protective conductor, Earth, ie the yellow and/or green wire

CPD - Circuit Protective Device

CSA - Cross Sectional Area -"size" as in CSA is/isn't important i

CU - Consumer Unit the thing usually next to the meter with all the electrical switches in it.

DB - distribution board

DC - Direct current what comes in and out of a battery, and some, usually low voltage, devices

DEI - Domestic Electrical Installer yer household electrician.

DI - Domestic Installer

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Good man!

SSO - single socket outlet

DSO - double socket outlet

TP - three phase or triple pole

ELECSA - another friendly certifying body

BRB - big red book (17th edition guidance)

CPC - circuit protective conducter

Ze - external loop impedance... (Path that earth fault will take back to the star point of transformer)

Zs - eath fault loop impedance... (Path of earth fault back to main earthing point)

R1+R2 - value of phase and cpc linked together while testing

Guiness Drink

and not forgeting CN - Central Networks :p :coat

Very good, here are some minor corrections & some additions

AC - NICEIC approved contractor

CPC - circuit protective conductor

DI - Domestic installer

IEE - Institute of electrical engineers (now the IET)

Part P - Building regulations which apply to all domestic electrical installations, all work comes under these regs, but only some types of work are notifyable

Part P - Qualification.... there isn't one really, although some training providers are doing this type of course which is described as an entry level qualification for scheme membership.... you still need to have an annual assessment by a scheme provider

Ze - the resistance of the line/earth from the consumers connection back to the generator/local transformer (inc the transformer windings)

R1 - the resistance of a circuits line conductor

R2 - the resistance of a circuits earth conductor

Zs = Ze+(R1+R2)

r1 - the resistance of the line conductor in a ring circuit (end to end)

r2 - the resistance of the earth conductor in a ring circuit (end to end)

rn - the resistance of the neutral conductor in a ring circuit (end to end)

There's NAPIT too

Worth noting that phase/live/line are synonymous!

OSG - on site guide

MFT - Multi-function tester

IR - insulation resistance

ccts - circuits or certificates

IP** - ingress protection, followed by 2 numbers

Not to forget:

CCU Cooker Conection Unit

CPD Circuit Protective Device

FCU Fused Connection Unit

SCU Switched Connection Unit

SFCU Switched Fused Connection Unit

MEBC Main Equipotential Bonding Conductor

MET Main Earth Terminal

PEN Protective Earth and Neutral

PME is Protective Multiple Earth, which I think you'll find is the new TN-C-S

RCCBO Residual Current Circuit Breaker with Overload protection

RCCD Residual Current Circuit Device

RCD Residual Current Device

With TT, TN-C, TN-S, TN-C-S and IT. The T refers to Terra (Earth), so TT is basicaly Earthed Earth, TN-C is Earth Neutral Combined, TN-S is Earth Neutral Seperated, TN-C-S is Earth Neutral Combined then Separated and IT is Isolated Earth.

TP&N Three Phase & Neutral

MIMS - Mineral Insulated Metal Sheath. See also MICC. See also Pyro.

PYRO - Abbreviation for Pyrotenax, a generic term for the MIMS / MICC cable type.

This trade must be the worst for using all these acronyms , then just as you get used to one ,they change it ( PME = TNCS You need to speak Latin to find that T stands for Terra =earth ) Or new ones appear from nowhere , I think what the hell is this guy waffling about , such as MET , Main Earth Terminal apparently , Itend to call it the Main Earth Terminal !! What I call an earth wire others call a CCP now. We used to check loop impedance now its called Zs . Don't even start me on the organisations attatched to the trade.

ECA , JIB, EEPTU, IEE, NICEIC, ELECSA, NAPITT , Oh! SODITT, they go on forever.
Don't forget the most important one BSI.