Why do electrical wiring colors have to be so complicated?

[Mark R]

So, I was thinking about installing an extra light-switch for my living room because the current switch is in an awkward place, and a 2nd would be nice.

Simple you'd think. Well, in theory, yes. Just install another switch and run a 3 between the old and new switch, and swap a couple of wires around

Well, the government, in their infinite wisdom (or specifically Brussles) have decided that the existing wiring colors weren't good enough, and needed to be changed.

My current home is wired with the old colors:
Neutral: Black
Live: Red (or in 3 wire systems - see circuit above: red, blue and yellow)

Perfectly sensible colors.

Unfortunately, any work I do in the future must be done in 'new' colors:

Neutral: Blue
Live: Brown (or in 3 wire systems: brown, black and gray)

Apart from the low contrast between the 3 live colors - it's not too bad. But when the 2 systems are mixed, then there is the prospect for all hell to break loose. If you haven't already noticed - black and blue have swapped roles. Black was previously neutral, and is now live. Blue was previously live and is now neutral.

Genius.

 

[BigJ]

You should be testing the wires to see what is what anyway.

 

[Fritzo]

Where are you at? Wiring here is black, white, and green.

 

[Engineer]

Brown for + and blue for - is the European color coding system.

By the way, black is normally the hot wire with white as the neutral. Green (or bare copper) is ground. I have seen black wires used for neutral and white used for hot but usually when wanting to run only one piece of Romex to a switch or something similar.

 

[RU482]

code schmode

I wire houses in all black wire

 

[2Xtreme21]

Who needs wires anyway?

 

[MrDudeMan]

Originally posted by: redly1
code schmode

I wire houses in all black wire

not sure why but this post made me LOL

 

[Ronstang]

Hmm, it is in the wall. Wire it the way you want and screw the government. That is what I would do.

 

[Engineer]

Originally posted by: Ronstang
Hmm, it is in the wall. Wire it the way you want and screw the government. That is what I would do.

As long as it doesn't have to be inspected, I tend to agree!

 

[cavingjan]

Doesn't this have to do with color recognition? Red and black are difficult to tell apart when using certain color flashlights.

Also the most common type of color blindness involves red. The move away from red could stem from that.

 

[theknight571]

My house, when I bought it, was still the original "knob and tube".

All wires looked the same, and most of the insulation was dry-rotted.

I think the original "electrician" was drunk when running it... cause it ran thought the house like spaghetti.

The entire house was 3 circuits... with no logical layout.

We've finally managed to replace most of it, and add more circuits. It's nice to be able to run the microwave and mixer etc all at the same time.

For those interested...

 

[Mark R]

Originally posted by: cavingjan
Doesn't this have to do with color recognition? Red and black are difficult to tell apart when using certain color flashlights.

Also the most common type of color blindness involves red. The move away from red could stem from that.

It is due to to color blindness. The inability to tell red from other colors is a major problem.

The color of wires in portable appliances (where end users might have reason to remove or rewire the plugs) has been in 'new' colors for about 25 years.

However, because the old and new colors conflict, there was always strong industry pressure not to use the new colors. The point being that in fixed wiring you're likely to come across both (where black and blue might be used for both neutral and live). As most fixed wiring is going to be done by a trained electrican, this wasn't much of a problem, because it's impossible to take formal training as an electrician unless you have normal color vision (most, if not all, electrician training courses will require a medical certificate of normal color vision before processing your application).

In the end, pressure from Europe won out. The other countries had switched color codes - the UK could do so to.

Just for sake of a pic: Here's a pic of my panel: IMG_6799.jpg

Main power from the meter comes via the big red and black cables, where it enters the main disconnects.

There are 2 supplies - the one on the right is the main supply. The one on the left is the off-peak supply. The meter switches the off-peak supply on whenever the cheap-rate is in use, allowing the water heater/room heaters to come on automatically in sync with the cheap rate.

Circuits come off individual breakers. Note the 'ring' circuits for receptacles where 2 wires leave the breakers.

The 'double size' breaker is includes an ELCB and serves the space heaters in the bathrooms.

 

[DrPizza]

When going to a switch, I don't think they're called hot and neutral, but rather, hot and return. I might have this backwards, but I believe that according to code, the wire wire is the carrier - that is, if you're going from a light to a switch, the wire from the breaker box goes to the electrical box the light is connected to. Inside that box, the black is hot, the white is neutral. When going from this box to a switch elsewhere, the *white* wire is connected to the black hot wire inside the light's box, to help avoid confusion. It should also be marked (generally by simply wrapping the end couple inches of the white wire with black electrical tape.) At the switch's box, the white wire will be hot; it should again be marked by wrapping a couple inches with black electrical tape. The black wire is the return wire which carries the energy back to the light.

Were this not the case, then someone, somewhere down the road, would be looking inside the light's electrical box and see two white wires connected to the light. There would be no way knowing which was hot and which was neutral, without testing. This way, black is hot (when the switch is on) and white is neutral inside that box.

 

[Mark R]

That's interesting that you use the white (albeit marked) as hot and black as switched hot.

Over here, permanent live is brown (red), and switched live is the neutral color marked with live color tape.

 

[Evadman]

Remind me not to go to europe. I would kill myself.

any color except green and white = Hot (black is always unswitched)
white = neutral
green or bare = ground


US = Win

 

[DrPizza]

Originally posted by: Evadman
Remind me not to go to europe. I would kill myself.

any color except green and white = Hot (black is always unswitched)
white = neutral
green or bare = ground


US = Win

So, I did have it backwards about the colors going from a light to a switch?

 

[Evadman]

Originally posted by: DrPizza
So, I did have it backwards about the colors going from a light to a switch?

hoenstly, it is hard to understand your post. White is always neutral and black is always hot, and bare or green is always ground no exceptions. everything else is open to negotiation but there are standards such as the runners in a 3 way switch are supposed to be red. If a conduit is full of switched lines, then different colors are normaly used for each circuit (hot and neutral), but you technicly don't have to.

A white wire that is hot will fail you no mater where it is. a while ago they allowed painting the end of the wires in the specified color (such as run all white but paint the ends black if they were hot which is I think what you are saying) but that is no longer allowed AFAIK.

Some inspectors will fail you if you don't use colors because the inspector is a lazy bastard and doesn't want to check to see if one neutral is used for 2 circuits. (over amperage on a neutral is just as important as on hot) but at least around here, you are not required to use any colors besides white and black. (conduit is allowed as ground around here)

 

[DrPizza]

Here, I drew a picture: here
(Yellow equals white, and I didn't bother with putting a ground wire in the diagram)

In the wire going from the light's electrical box to the switch, does code dictate which wire is which? (black taking the hot to the switch, or black returning the hot from the switch). But, either way, white is *not* neutral in that part of the wiring.) This type of circuit would be the most efficient way to wire a ceiling fan with a light kit - the light can be turned off at the switch, leaving the fan running.

 

[Evadman]

Originally posted by: DrPizza
Here, I drew a picture: here
(Yellow equals white, and I didn't bother with putting a ground wire in the diagram)

That's not code because the white (yellow in the pic) from the switch to the light is switched hot. If the wire is hot, ever, it can not be white.

 

[DrPizza]

Originally posted by: Evadman

Originally posted by: DrPizza
Here, I drew a picture: here
(Yellow equals white, and I didn't bother with putting a ground wire in the diagram)

That's not code because the white (yellow in the pic) from the switch to the light is switched hot. If the wire is hot, ever, it can not be white.

Weird, because I've installed ceiling fans in a recently built home that was wired by an electrician. It's also shown that way in several diy books I have laying around. Are you sure (that it's according to the national electrical code, vs. some local code)?

 

[Minerva]

Originally posted by: Mark R
Here's a pic of my panel: IMG_6799.jpg

That's so clean compared to this.

Federal Pacific! When you never want to trip you use FPE! :laugh:

 

[Colt45]

the switch should be in the middle of the neutral wire between the power source and the light. the way it's drawn its on hot, and drawn really weird.


err nevermind, switch the hot, but you still have it drawn weird

and the piece of white between the switch and the light should be black


i just woke up

 

[DrPizza]

Okay, I did some googling.
I did have it backwards; the white wire *can* be a hot wire, but only when used as a return from the switch, not carrying the power from the light's box to the switch. Thus, the diagram I drew is correct and to code.

 

[AlienCraft]

Originally posted by: redly1
code schmode

I wire houses in all black wire

That's Racist :disgust: :Q