Wiring question (at the breaker)

[ivwshane]

While doing my laundry room remodel I disconnected the dryer wire (10/2) at the breaker but stupid me forgot to write down what goes where.

I know that the wire connects to where I have the arrows in the picture but I wasn't sure if it mattered which slot the black or white wire connect to.

Can someone please confirm that it doesn't matter which wire connects to which post in the pic or tell me what goes where.




Slightly off topic
My current dryer is wired using a 3 pronged plug and I know that using 10/2 cable in the past was standard but now dryers are wired using a 4 wire/prong setup. When I get my new dryer, if I want to be up to code, how would I wire it up? Black to top/bottom (indicated by the arrows in the pic) and the red wire to the other spot and the white to the neutral and the ground to the ground bar?

[pelligrini]

I don't think it matters for those two wires, each one is going to connect to each one of the two legs at the panel. I'm no electrician, nor familar with the elec code. I'm sure someone more knowledgeable will have an answer.

[Daryl]

As I understand it, you have a black and white wire going to two different breakers. It doesn't matter which breaker either wire goes to.

[Tom Slick]

As the two above have posted, it doesn't matter with single phase, either wire can go to either terminal the arrows indicate. You are correct with the white to neutral, bare to ground.

[eezlock]

wiring question

The red and/ or black wires go under the breaker lugs....nothing else.White wire
goes to the neutral bar, bare or green goes to ground bar.

[Mr__Bill]

I'm sure and electrician will weigh in and clarify thing but till then. A three wire dryer has two hots and a ground. A four wire dryer has two hots a common and a ground. For the 3 wire the black and white connect to the breaker and the ground to the ground/neutral bar. With 4 wire you have black and red to the breaker and the white to neutral/ground and the ground/neutral bar. Some of the newer dryers will give a diagram of how to wire a 3 wire plug safely to the dryer and you can avoid running a new wire for the dryer. Some really do use 120V and must have 4 wires.

Bill

[twistsol]

With the three wire, you are correct that the black and white are tied to the two hot lugs on the breaker. You are supposed to color the white either red or black. A sharpie works well for this. Our local electrical inspector carries one and colored about five wires in my breaker box the first time he was out.

For a four wire setup, white and ground go to the neutral bar or neutral and ground if they're separate. The red and black go to the two hot lugs on the breaker and it doesn't matter which one goes where.

[reddog552]

I dont know who wired your panel,I see at least 10 code violations.

[LJR]

Unfortunately reddog is correct, there are code issues in that panel. Issues that leave you unsafe. You don't list your location, if you're in the Ks. City area I would be glad to come by and show you what's wrong and how to correct the installation. If you're not in the area I would suggest you get someone to come to your location and help you.

[Black wallnut]

I dont know who wired your panel,I see at least 10 code violations.

Then how about being helpful and specifically identifying them.

[ivwshane]

I dont know who wired your panel,I see at least 10 code violations.

I'm in California but by all means let me know what you see wrong!

[woodturner]

Can someone please confirm that it doesn't matter which wire connects to which post in the pic or tell me what goes where.

What color are the wires?

As others noted, a 3 wire dryer circuit should have 2 hots and a neutral, and a 4 wire has two hots, a neutral, and a ground. With the three wire circuit, the dryers should be separately grounded to a good earth ground.

You SHOULD have three wires in your cable - one black, one red or black, and one white. It's likely, however, that your dryer was wired with NM-B cable, which would have one black, one white, and one bare wire. If that is the case, it is not code compliant and the cable should be replaced.

In any event, the dryer has three connections - two hot wires and one neutral. Either hot wire can be connected to either pole of the breaker, it doesn't matter. The neutral should be connected to the neutral bar in the panel.

BTW, 10 guage wire is a little small for a dryer.

Regarding code violations, the only one I noticed off-hand was the sheathing within the panel. The plastic outer sheathing from NM-B cable should not extend more than 1/2" inside the box, per code.

[ivwshane]

It was wired with a 10/2 nmb cable so one black, one white, and a bare cable.

Since I'm getting a new dryer and I have access to the walls and cabling should I just replace it now?

If so, what wire should I get and what does a four pronged dryer outlet look like?

[woodturner]

Since I'm getting a new dryer and I have access to the walls and cabling should I just replace it now?

If so, what wire should I get and what does a four pronged dryer outlet look like?

I would suggest replacing it now. The cable you want will have four wires - red, black, white, and a bare copper wire. You can still wire it for three wire for now and just wire-nut off the unused wire.

Wire size depends on load and cable length. I would typically use at least 6 guage for a 20' wire run. There are tables in the NEC that will tell you the code-required wire size. I recommend increasing the size at least one step beyond code - e.g. if code says 8 guage, use 6 guage. This will significantly reduce the light dimming and other voltage drop effects and may extend the life of the dryer.

[ivwshane]

I don't know if your recomendation will change but the run is less than 15' long.

I'll go ahead and replace it now then.