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After many pitfalls, I have gotten my new dryer working. It's a Kenmore 81182 electric dryer. (Manual from sears; Sears website). Very long story short, the neutral wire at the breaker box wasn't tight, at all, not in the least (how my previous dryer ran 10 years is a mystery).

Got that squared away, but I am wondering if the 30amp dryer should be on a dedicated 50amp breaker. I had it off for two days and noticed all other appliances working in the house (fridge, washer, dishwasher, oven, stove, central heat/air). The panel at the box is not labelled, but a nice little piece of cardboard inside the box labels the slot "dryer".

Shouldn't this appliance be a 30amp breaker? Or am I misreading "minimum circuit rating = 30amp"?

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  • There is a lot of bad info out there. Code is very specific on the outlet rating. Table 210.21.b.2 states a 30 amp circuit can have a 30 amp receptacle with the max load of 24 amps. Table 210.21,b,3 also shows 30 amp circuit rating with a 30 amp receptacle, you can use larger wire but a 30 amp receptacle cannot have a smaller or larger breaker than 30 amp by code. There are exceptions but they don't apply to a dryer.
    – Ed Beal
    Commented Jan 15, 2019 at 23:10

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Your question is a bit convoluted, but the answer is very simple. The breaker size must match or be lower than the wire amp rating feeding the circuit, and appliances on that circuit should not exceed the max rating of the wire or breaker. In a dedicated circuit for a dryer, for example, the normal size of the circuit would be 30 amps. 30 amps requires a minimum of #10 copper or #8 alu. With this wire size, the breaker must not be larger than 30 amps. Do not use a larger breaker then what the current rating of the wire is rated for.

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NEC 110.3(B) Installation and Use Equipment that is listed, labeled, or both, or identified for a use shall be installed and used in accordance with any instructions included in the listing, labeling, or identification. Informational Note: The installation and use instructions may be provided in the form of printed material, quick response (QR) code, or the address on the internet where users can download the required instructions.

The version of the instructions online in 2024 on page 12 says:

The dryer has its own terminal block that must be connected to a separate 240 VAC, 60-Hertz, single phase circuit, fused at 30 amperes (the circuit must be fused on both sides of the line). ELECTRICAL SERVICE FOR THE DRYER SHOULD BE OF THE MAXIMUM RATE VOLTAGE LISTED ON THE NAMEPLATE. DO NOT CONNECT DRYER TO 110-, 115-, OR 120-VOLT CIRCUIT.

So no, it should not be used on a 50A circuit, the instructions say 30A.

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In reply to: "but I am wondering if the 30amp dryer should be on a dedicated 50amp breaker."

Your question may have been better worded as: "but I am wondering if the 30 amp dryer should be on a dedicated 6 gauge copper wire circuit with a 50amp breaker."

The first duty of a breaker is to protect the wiring and in your case it sounds as though you have a 10 gauge copper wire circuit which normally requires a 30 amp breaker or less (the breaker amps can be smaller but normally not larger than the amps the wiring will carry). The appliance is a secondary consideration because if it draws more than the circuit will carry then all that should happen is the breaker trips and no fire.

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The 50 amp refers to the capacity of the circuit: in particular the wires. The dryer can, and likely does, draw much less, similar to plugging a 60 watt light bulb into a socket rated for a 100 watt bulb. This itself is not a problem.

That said 30amp is more typical. If that circuit runs one 30 amp outlet (http://fam-oud.nl/~plugsocket/NorthAm-3hd.html ) then a 30 amp breaker is proper. While you can measure all the circuit elements starting with the wires to see if they match a 50 amp circuit, it's probably just easier to drop a 30 amp in there and be done with it. 30 amp is paired with #10 wire (complicated exceptions beyond the scope of this answer apply).

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  • Receptacle(13 in your link) is 30amp with #10 wire. Plug(14 in your link) and wire came new with machine. Wiring was redone in the whole house circa 2005.
    – gm70560
    Commented Mar 27, 2014 at 5:39
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    From what I can see you're better off with a 30 amp breaker. The NEMA 14-30R plug/socket you have is 30 amp and you want the weakest link in your circuit to be the breaker.
    – Bryce
    Commented Mar 27, 2014 at 6:19
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The 50amp will not kick as easy as the 30amp. So as long as your dryer is perfect you'll be ok but you can be in real trouble if it over heats or something goes wrong.

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    Without knowing the wire gauge this could be a dangerous answer.
    – Ed Beal
    Commented Sep 9, 2017 at 15:16
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Electrical Engineer here. The device you are protecting is what determines the breaker size. In your example, your dryer will likely have a nameplate which will provide its operating current. This value is usually slightly less than the breaker rating. For example, a random GE electric dryer I found on Home Depot has a rating of 5600W @ 240V, which will pull approximately 24 amps.

Now, why would you not size the breaker at 25 amps? Well, technically, I don't think there would be anything actually dangerous with doing so, however, the voltage at the outlet may not actually be 240V. Your utility may have some voltage drop at the transformer, and depending on the length of the conductor from your breaker to the dryer, you may have some voltage drop too. With voltage drop, comes a rise in current. There is also inrush current on the motor during startup, which may spike current temporarily. If that spike is more than the breaker rating, it will trip. This is why the typical breaker for a dryer circuit is 30A.

Now to answer the original question, can you put a 50A breaker on a 30A device. The short answer is no. The device will work, but in the event of a fault on the device, the current may not be high enough to trip the breaker, but it will be high enough to cause damage inside the dryer or to melt the wire from the breaker to the device (assuming its wire rated for a 30 amp load). The manufacturer will typically list the maximum/minimum size breaker required.

Finally, wire size. As long as the wire ampacity meets or exceeds the breaker size and the amp draw of the dryer, you are good to go. Just be sure to take voltage drop into account, 3% is the max allowable drop. If you have a long run from the breaker to the dryer, you may need to size up. I did this for my A/C compressor, which requires 30A breaker. 10 awg wire (typical for 30 amp circuits) was right on the edge of having too much drop for the length of my run, so I sized it up to 8 awg just to be sure. Really, the only downside to sizing up wire is a bigger hole in your pocket haha. Hope this helps.

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  • Please break it into paragraphs
    – Rohit Gupta
    Commented Nov 21 at 4:28
  • There are still major factual errors. Dryers that draw 24A can't go on 25A circuit breakers (in NEC land) because of the 80% derate rule. 3% voltage drop is a suggestion, not a rule (outside of Canada at least). Finally, the question is more than 10 years old, and this answer isn't really adding anything that wasn't already covered by the previous six answers.
    – nobody
    Commented Nov 22 at 0:42
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You can use the 50 Amp breaker if you use a sub panel. In the second or sub panel the 50 maps can feed 1 30 amp and 1 20 amp breaker. This will power both the washer and dryer from the sub panel. Just be sure the ground in the sub panel is NOT connected to the white neutral bar. Ground needs a clear path back to the main panel as well as neutral(white).

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  • Where did you come up with a sub panel?-
    – Ed Beal
    Commented Jan 15, 2019 at 23:06

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