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BS, IEC colour codes

BS, IEC colour codes

BS, IEC colour codes

(OP)
Hi,

I'm trying to work out cable colours for a control panel. The colours for AC wiring seems quite well documented, but does anyone know any details for 24VDC wiring?

I've been searching and i'm having trouble trying to find any convention. I think i read that there is a BS for machine colour coding and that states blue for control wiring (going by what people have said, i never read it myself!).

However, would supplies to PLCs etc (+24VDC and 0V) be blue aswell? I'm used to seeing red(+) and black(-), could that be used, or can i use whatever colour i feel like? Heh.

Ross

RE: BS, IEC colour codes

(OP)
Any ideas?

Our wiring technician is begging me to let him use a colour other than blue for control wire, but until i find out blue he shall use!

RE: BS, IEC colour codes

We typically use blue for our control cables as well.  I'm not certain if it an accepted standard though.

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If it is broken, fix it.  If it isn't broken, I'll soon fix that.

RE: BS, IEC colour codes

Different standards for different industries. We typically used the following colours for panel wiring:

24V DC - grey
110V AC or DC - black
415/240V AC - red / yelllow / blue / black in the good old days
415/240V AC - brown / black / grey / blue - post-EU meddling
Alarms - orange
I.S circuits - mid blue
Other stuff - designer's discretion.

The following might be of use for installation work as opposed to panel wiring: http://www.theiet.org/publishing/wiring-regulations/colour/col-harm.cfm
  

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If we learn from our mistakes I'm getting a great education!
 

RE: BS, IEC colour codes

usa or north america

black -voltage greater than 120vac, tape on both ends for 480vac red, yel, brn for sequence

orange - 120vac power

red - 120vac control signal

white - 120vac neutral

blue or brown - dc power

blue - dc control signal

grey - dc common or neutral

green - equipment ground

yellow - system interlocks

RE: BS, IEC colour codes

Orange is by NEC definition the wild leg of a 240V, 3-phase, delta system.  It isn't limited to that use by code, but where a wild leg exists it is required to be orange.

208Y/120V power typically is Black-Red-Blue, but not required to be so by code.

480Y/277V power typically is Brown-Orange-Yellow (BOY), but again, not required to be so by code.

RE: BS, IEC colour codes

(OP)
Thank you for the replies everyone, but can i remind you that BS/IEC are standards from the United Kingdom, so that was what i was looking for.

Thanks again.

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