IEC Conductor Colour Codes

[sfardella]

I am designing a control system for an international (IEC standard) customer and would like to verify the colour coding for the conductors:

3 Phase

Phase A - Black
Phase B - Red
Phase C - White
Neutral - Light Blue

Single Phase

AC Power - Black
AC Control - Red
AC Neutral - Light Blue
DC Control - Blue
Interconnect Control (externally powered) - Orange
Ground - Green/Yellow

I have seen some places that single phase colour coding is:

AC line - Brown
AC neutral - Light Blue
DC control - ????

I am a little confused in this matter - any insight would be helpful and references to specific standards are appreciated!

 

[jbartos]

Suggestion: It is stated in this Forum as:
Machine Builders and Industrial Electrical standard insulation Wire Color code for most Industrial Plants.
Blue = dc control wire (24vdc) to (120vdc).
Yellow = 120 vac from an outside power source.
Red - 120 vac control circuit.
Black = 120 vac (x1) Hot wire or 220 vac
White = 120 vac neutral wire (x2)
Green = ground wire
(x1) is the black and (x2) white wires on the output side of a Control transformer.
IEC for 120 vac
Brown = 24 to 120 vac Hot wire
Blue = 24 to 120 vac Neutral wire
Green/Yellow Strip = Ground wire
Black = 3 phase motor wiring.
For 3 phase Motor starter (L1-L2-L3) Line source
(T1-T2-T3) Load side to Motor
For 3 Phase Rotation or (phasing) A= Red B=Black C= white

 

[busbar]

In the US, internal to control cabinets, NEMA ICS-1 has established the practice of

Black — “line and load (AC and DC) power and motor circuits”
Red — “AC control circuits”
Blue— “DC control circuits”

with a notation that white and green be used under their default premises-wiring applications.

 

[EEIre]

Be careful with this as most European countries have still their own colour codes. The colour codes have now been fully harmonised across the EU countries yet.

For example Ireland where I work the colour codes are:
 L1 – Brown
 L2 – Red
 L3 – Yellow
 Neutral – Blue
 Earth – Green/Yellow.

The proposed harmonised colour codes proposed by CENELEC are:
• Earth: Green/Yellow
• Neutral: Blue
• Phases: Brown (first phase)Black, Grey

The date fot the implementation of this harmonised code has not been announced by CENELEC yet so you should revert to the national wiring regulations of the country where the equipment will be installed.

Regards

Sean

 

[sfardella]

FYI - received from collegue in Netherlands.

Below the colour codes we use in Europe...

3PHASE:
Phase L1 Brown
Phase L2 Black 1
Phase L3 Black 2
Neutral Blue
Safety- ground, instrument-ground Green Yellow

1PHASE:
AC Power main current - Brown
AC Control - Switched main current,
230VAC controlling current Black
Neutral Blue
Safety- ground, instrument-ground Green Yellow

Other AC Voltage:
From save altered Current (24VAC, 42VAC ……) Red
Common from save altered current White
Safety- ground, instrument-ground Green Yellow

DC Voltage:
Phase from save direct current (plc inputs etc) Orange
Common from save direct current Green
Measurement signals Yellow
Voltage initiated in relay assembly Purple
Hazards direct current Grey
Safety- ground, instrument-ground Green Yellow

 

[wired1]

The European standard most often referenced is called EN60204. I believe it existed as an IEC standard prior to the CE Low Voltage directive. It seems to have universal acceptance if not "official" acceptance. Most of your questions on color codes are covered in this. I don't have any knowledge about efforts to harmonize the colors for 3-ph. systems. It's best to check with your customer on this if they are not part of the EU.