# hooking up dryer....bronx ny code



## SURFBUG (Oct 11, 2008)

anyone?

any pointers would be appreciatted....

al


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## Nestor_Kelebay (Jun 17, 2008)

You'll get much more input if you posted this in the electrical forum rather than the appliance repair forum. Normally, an electric dryer requires 30 amp 220 volt service, and it's electricians that would know what the electrical code requirements are for running such a wire to a dryer, not appliance repair people.

When your dryer starts making a funny noise, then this would be the correct forum to post in. The immediate problem of finding out how to correctly connect the dryer to your electrical panel is something an electrician would know, not an appliance repair tech.


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## Nestor_Kelebay (Jun 17, 2008)

Surfbug:

I wrote up the following blurb years ago when I posted on a different board. It explains the basics of 110 and 220 volt house wiring. It won't answer your code questions, but it will ensure that you know enough to do this job without hurting yourself:

220 volt power that is supplied to homes is delivered via two power lines and a neutral wire. The two power lines each carry 110 volts AC, but they are "out of phase" by 180 degrees. That is, when one power line is at +110 volts with respect to the white neutral wire, the other power line will be at -110 volts with respect to the white neutral wire, and vice versa. So the voltage you would measure between the two power supply lines would be 220 volts AC. On appliance wiring diagrams, the two power lines will typically be called "L1" and "L2" for "Line 1" and "Line 2". In practice, Line 1 and Line 2 will ALWAYS be the red and black wires (meaning the insulation on them will be red or black in color), and the neutral wire is ALWAYS white. Grounding wires will be green or bare (with no insulation).

The technically incorrect but easiest way to think about this is that the power comes "in" on the red and black wires and goes out on the white wire. Obviously it doesn't, but that way of thinking about it will at least help you better understand house and appliance wiring. Also, if the black supply wire is feeding a 110 AC voltage sine wave into the white "return" wire and the red "supply" wire is feeding an equal but opposite voltage into that same white "return" wire, then theoretically, there should be no voltage or current in the white wire because the opposite voltages (and hence currents) would all cancel out in that white wire. If all electrical loads were purely resistive, like light bulbs and toasters and electric ranges and coffee makers, then there would be very little current or voltage in that white wire. However, in the real world there are electric motors and television sets and computer monitors, all of which have some "impedance". In an electric motor, for example, the magnetic fields created by the electric motor windings impeded the flow of current through the motor windings, so the motor windings cause the current sine wave coming out of the motor to lag behind the applied voltage sine wave. Also, television sets and those old CRT style computer monitors have huge capacitors in them, and that causes the current sine wave coming out of those computer monitors to actually preceed the applied voltage sine wave. So, even though the red and black wires carry equal and opposite 110 AC voltage sine waves, then timing differences caused by "reactive" loads like electric motors and television sets can result in there being significant voltage and current in the white wire. So, treat every wire as having dangerous voltage in it.

The standard 110 volt circuits for the ceiling lights or electric outlets in your house are made by connecting those circuits between the white neutral wire and EITHER the main red wire OR the main black wire coming into your house. All of those connections are made in your electrical panel and a fuse or circuit breaker is provided for each such circuit in your house. So, some of the 110 volt circuits in your house that go to lights or electric outlets are powered by the red wire, and some are powered by the black wire. As long as the circuit is between the red wire and the white wire, or between the black wire and the white wire, you have a 110 volt AC circuit. If you put a 15 amp fuse or breaker on that 110 volt circuit in the panel, then you have a 110 volt 15 amp circuit, and normally the circuits going to the lights, ceiling fans and electrical outlets in your house will be 110 volt 15 amp circuits.

220 volt circuits for the house's electric stove and electric clothes dryer are made by connecting the circuit between the main black and red wires at the electrical panel. Both the red and black wires carry 110 volts AC with respect the the white neutral wire, but because they're 180 degrees out of phase, there's 220 volts AC between the red and black wires. So, if you connect a circuit between the main black and main red wire going into the house, then you have a 220 volt circuit. If you're wiring a range, you normally need a 50 amp circuit, which requires a 50 amp breaker on BOTH the red and black wires going to the range. If you're wiring an electric dryer, you need a 30 amp circuit, so that means you must have 30 amp breakers on both the red and black wires going to the dryer. The fuses and breakers that control the current through every circuit are located inside your house's electrical panel.

When you open a typical electrical panel you'll notice that the fuses or circuit breakers are typically arranged in two vertical rows; one on each side of the panel. Do not assume that one side of the panel is for tapping off the red power line and the other is for tapping off the black power line. The buss bars inside the electrical panel determine what gets connected where, and often breaker positions above one another on the same side of the panel will be connected to opposite voltage sources. This is done so that the circuit breakers can be "ganged together" so that you can't flip the breaker off to one power line going to a stove or dryer without turning the power off to BOTH power lines. In Manitoba, the electrical code requires that circuit breakers for 220V appliances be "ganged" together in this way for safety reasons.

There is a standard wiring convention used when wiring the plugs, receptacles and terminal blocks of 220 volt appliances, all of which will have provision for connecting THREE wires as well as a ground wire. Normally the ground wire terminal will be easy to identify because it will be grounded to the electrical box by an electrical conductor, and the remaining three connection points will be arranged in a row of three connection sites. The wiring convention is that the white neutral wire is ALWAYS connected to the middle terminal in that row of three connection sites, and the red and black wires are connected on either side of it. It doesn't matter which side you connect the red or the black to, as long as the white is in the middle and the red and black are on the outside, you're good to go. If your stove or dryer doesn't come with a cord and you want to connect one to the terminal block of the appliance, the same rule applies, namely "white in the middle, black and red on the outside". If you're wanting to wire a receptacle for a stove or electric dryer, then again, the same rule applies. First identify the ground wire terminal, and the remaining three connection points will be for the red, white and black wires and they should be arranged in a recognizable "row". Always connect the white in the middle of those three sites and the red and black on either side of the white. This point has now been officially hammered into your head; for 220 volt AC wiring, white goes in the middle, black and red go on either side.

Every dryer cord will have 4 prongs sticking out of it. The straight ones are for the red and black wires, the "L" shaped one is for the white wire and the round one is for the ground wire. Range cords also have 4 prongs, but they will use 3 straight prongs for the red, black and white wires and a round one for the ground wire. Configuring the plug and receptacle differently (with an "L" shaped prong instead of a straight one) is done so you can't stick a 30 amp dryer plug into a 50 amp range receptacle or vice versa.

The heating elements in both electric dryers and stoves require 220 volt power, but you still need to run the white wire to the stove or dryer. The reason why is that there will be circuits within the stove or dryer that require only 110 volt power. For example, the electric motor that turns the dryer drum or the light bulb inside an oven will both require 110 volt AC power, not 220 volt power. So, in an electric stove the heating elements will be connected between the red and black wires because they need 220 volts, but the electrical outlets provided for convenience on the stove console will be connected between the white wire and either the red or black power wires, because the convenience outlet is intended to provide power to 110 volt AC appliances. Since the main black and red wires going to a stove are fused at 50 amps each in the electrical panel, any circuit between the red and white OR black and white wires in the stove will give you a 110 volt 50 AMP CIRCUIT. That would present a dangerous situation if the convenience outlets on the stove's console were fused to 50 amps. A short in a coffee maker's heating element would draw 50 amps before the fuse or breaker in the electrical panel blew or tripped to shut off the flow of electricity to the coffee maker. That's why for the electric outlets provided for convenience on range cooktops, there will be a 15 amp fuse right in the range somewhere that fuses each convenience outlet down to 15 amps. If you have two cooktop plugs, one will be driven by the red wire and one by the black wire, and each will have it's own separate 15 amp fuse to limit the current through that circuit.

That's the end of the blurb. I agree it's simplistic, but it outlines the basics of 110 and 220 volt wiring for someone who migh otherwise not have a clue about it.

Still, post in the electrical forum to get specifics on the kind of wire to use and whether the additional 30 amps required by the dryer means you have to upgrade your electrical panel or add a sub-panel.


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## SURFBUG (Oct 11, 2008)

yes, that is info packed?


I looked at the 10/3 wire and the 8/3 wire



with a run that long, do you think I need 8/3 cable?


or would 10/3 be good enough?

al


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## Nestor_Kelebay (Jun 17, 2008)

SURFBUG said:


> yes, that is info packed?
> 
> 
> I looked at the 10/3 wire and the 8/3 wire
> ...


Like I say, that's a question that you have to turn to the Electrical Code to answer. You need wiring rated at 30 amps cuz that's how much the dryer may draw and that's how much the breakers or fuses to the dryer will be rated at. If you can't get any answer in here or in the Electrical forum, then phone your local city hall and ask to speak to the electrical inspector for new construction. If he won't give you an answer, go to your local home center and take a look at the conductors in a dryer cord, and look for a wire with 3 conductors and a ground wire of similar size.

I THINK that armored BX cable is only required in commercial installation. If this is a residential application, you might not need to use armored cable, but you're talking to a guy who knows squat about the Electrical Code here in Manitoba, let alone New York State.


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## rgsgww (Jul 5, 2008)

Normally you would use 10 awg, but in this situation, your probably going to need to use 8/3 romex because of the voltage drop, with a 30 amp double pole breaker. Use a 4 prong grounded dryer outlet. If the wire runs down a wall exposed, it will need to be protected in conduit.

Check with local codes though, ex. Chicago requires all conduit.


What is the amperage of the main breaker?

DONT BUY ROMEX IN THE BIG BOX STORES! Buy it at a good supply house, way cheaper prices.

Check with your city, they will say if you will need a permit, and an inspection. Normally this is considered small work, but it might be different there.

Somebody should move this thread to the electrical section....


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