ECN Forum Forums General Topics of the Trade General Discussion Area Color codes revisited

Scott35,

If both of these systems are in the same building and you are using multiwire branch circuits, then 210-4(d) requires that each ungrounded conductor be identified as to phase and voltage. The method of identification is left to the designer/installer but must be posted at each branch-circuit panelboard in the building. This requirement only applies to multiwire branch circuits and does not require the use of special identification of the grounded conductors. 200-6(d) would require that where both grounded conductors are in the same raceway, junction box, ect that the first grounded conductor be white or natural gray and the second grounded conductor be white with a colored stripe other than green.

Two more questions occurred to me while pondering on all this.

1. Normal 120/240V 3-wire residential. When connecting black and red (whether Romex or conduit) to a double-pole C/B for 240V branches, do you always match colors?

That is, will red on say the dryer branch be to the same hot busbar as red on the range branch, or are black and red just connected randomly?

2. When Romex is used for 3-way switching, which way round are the colors normally used? White (marked) still for the common in and out, then black and red for the travelers?

>1. Normal 120/240V 3-wire residential. When connecting black and red ... to a double-pole C/B for 240V branches, do you always match colors?
No.

>will red on say the dryer branch be to the same hot busbar as red on the range branch, or are black and red just connected randomly?
Generally random.

I occasionally orient them if circuits will be in proximity.

>2. When Romex is used for 3-way switching, which way round are the colors normally used? White (marked) still for the common in and out, then black and red for the travelers?
It depends on where the source is with respect to the load, of course.

I like to end up at the luminaire with black and white. That means that sometimes white is remarked yellow or blue.
I use white from the source to the luminaire.
I use black from the source to the first switch.
I use black from the last switch to the luminaire. I think that is enough for you to figure out how I do it.

My way is probably uncommon.


[This message has been edited by Dspark (edited 09-29-2001).]

For single phase, I put black on the left or bottom (same as with receptacles). The means that red goes on the right (same as white on a receptacle).

When I put multiple panels in a house, they are all this way. That usually puts red on the left side busbar. It is useful only in those rare instances when I deliberately want to distribute two loads, and when I want to avoid a 240 V situation (e.g., a bathroom).

DSpark.
Please explain why this puts red on the left busbar.
I don't get it!!!
(you're talking nonsense!)

Its been my habit to start all the 2 pole 240 volt circuit breakers at the top of the panel in residential work. When I do a multi-family building all the panels are hooked up the same way as far as possible. It makes for a neater panel. No code requirement just a work habit I got into years ago.
On 3 way and 4 way switches I use either 14-2 or 12-2 romex from panel to first switch 14-3 or 12-3 to next and/or last switch then 14-2 or 12-2 to the light fixture(s).
Again a work habit. This keeps the white as a neutral the bares as ground thru out. I found this sure cuts down on mistakes and helps eleminate trouble shooting time when something is not right. It also makes teaching newbys a lot easier.

>Please explain why this puts red on the left busbar.

Many main breakers cross the feeds. Cutler-Hammer 200 A single phase panel is a suitable example.

If you check the instruction, they make this very clear and a simple voltage test proves that they are correct.


[This message has been edited by Dspark (edited 10-05-2001).]

>Its been my habit to start all the 2 pole 240 volt circuit breakers at the top of the panel in residential work.
If I can lay them out in advance, I like to group them by story and wing.

>This keeps ... the bares as ground thru out.
I should hope so!!!!

>It also makes teaching newbys a lot easier.
But it can require some extra wire and a lot of extra wire to add another four-way into a circuit.

The pics of residential panels I have here all seem to have the main lugs at the top and busbars arranged for two columns of breakers, mounted sideways. All the panels I saw while over there were like this as well.

Is this the norm for residential panels, or are there other layouts as well?

>Is this the norm for residential panels, or are there other layouts as well?

Yes. The panels are made to fit between 2"X4" studs on 16" centers.

The main breaker may be at the top or bottom and sometimes in one column, both, and sometimes even oriented vertically rather than sideways.

Sideways orientation turns out to be a good thing when labeling the individual breakers, which of course, everyone does.