EN60204 Wire Colour for DC Supplies

[DaveDLS]

EN60204 recommends the following wiring colours...

- BLACK: a.c. and d.c. power circuits;
– RED: a.c. control circuits;
– BLUE: d.c. control circuits;
– ORANGE: interlock control circuits supplied from an external power source.

...but no clarification as to what constitutes a 'dc power circuit'. Some people in my organisation take this to mean even the +24V supply out to DC control circuits (relays, contactors, pusbuttons etc) should be black.

I think that +12, +24VDC should not be considered 'power', as to make these wires black and thus indistinguishable from 415V 3 phase cables seems to defeat the object of having colour codes?

Would be interested in any comments.

 

[Blackcountryman]

In the past when I have worked on cranes with dc motors the 'power' wired in black was the from the variable speed drive to the motor, that is the high current circuit. The control element also in dc but at 24v dc would be control wired in blue.

Hope this helps

 

[DaveDLS]

Thanks for the reply, I agree with you about DC outputs from Inverter Drives etc, they should be in black, but for the time being I think I'll carry on wiring the +24V supplies etc in blue.

 

[ScottyUK]

Perhaps the only thing to add is that you may need to choose the shade of blue carefully. A dark blue will be fine, but a lighter blue is typically reserved for intrinsically safe circuits, if you have such things on your plant. The colour on such circuits is typically used on cable insulation, terminals, and IS barrier housings and makes for an instantly recognisable installation.


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