Red, blue and black cable

littlespark said:

BTW, @buzzlightyear why is your diagram showing the cores in the wrong order? Old 3 core and earth is red, yellow, blue…. And your new cables on the right are similarly mixed up…. Should be brown, black, grey.

Click to expand...

6 Changes to cable core colour identification​

Table 7B – Cable to BS 6004 (flat cable with bare cpc)​

littlespark said:

In some older buildings where there was 3 phase supplies serving single phase loads, and the installation was singles in conduit…. The phase colours were used.

So normally where you would see red, black and g/y, you could have yellow, black, g/y or blue, black, g/y

If metal conduit, there may be no green/yellow…


What is the situation you have found?



BTW, @buzzlightyear why is your diagram showing the cores in the wrong order? Old 3 core and earth is red, yellow, blue…. And your new cables on the right are similarly mixed up…. Should be brown, black, grey.

I’m not 100% certain the cpcs are in the right place either.

Click to expand...