×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Conductor Colour Codes

Conductor Colour Codes

Conductor Colour Codes

(OP)
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.

RE: Conductor Colour Codes

Your chart seem to be one step off, the list you used for 1 PH should be for the 3 PH, the list for Brown, Light Blue and DC dark blue is correct for 1 PH. I'm not sure where you got Black, Red and White for 3 PH but I don't think it is correct. Anyways stick to your single PH colors for 3 Phase and the last set of colors for single PH and use numerical identification when there could be confusion.

Good Luck

Christopher Caserta
ccaserta@us.tuv.com
Ph:904-225-0360

RE: Conductor Colour Codes

(OP)
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        

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources