this post was submitted on 01 Jul 2025
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Hello,

I'm trying to shop around for a possible extension cord for this 250v, 50amp outlet.

We'd be trying to use an electric dryer from this, but would preferably have it extend nearer a window on the other side of a garage (~25-30 ft, generous measurement). We'd likely pick up an older, used, basic dryer model, and not sure what those electrical needs will specifically be, but trying to plan ahead in case something needs to be altered.

This is the closest I've found which might work:

https://www.homedepot.com/p/VEVOR-Extension-Cord-25-ft-10-Wire-Gauge-Heavy-Duty-Outdoor-Welder-Extension-Cord-with-3-Prong-30-Amp-Power-Extension-HJLJQ10-3-25FTYCXV1/320761106

Most other cords with 3 prongs had them sort of curved/circular. Yet, this says only 30 amps.

Is there different or specific wording which might assist my search? Or would something like the above cord work for our situation?

Thank you for taking the time to read my post. I appreciate any advice or directions.

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[–] [email protected] 3 points 1 day ago (2 children)

Just as a general comment, it might be worth running normal house wiring to a new location just out of pure economics. A proper extension chord is going to be expensive for 250v 50amps. House wiring, even the heavier gauge stuff for the higher amperage, is much cheaper than an extension chord because wall wiring is a solid wire and doesn't need to be constantly flexible. An extension chord is basically always many stranded wire so that it is more supple, which isn't as capable of carrying current. Thusly, they're always much thicker and with tougher, more expensive casing than static wall wiring as well.

It miiight not be applicable, and maybe the costs have changed in recent years or are different in your area, but always worth considering a cheaper option.

The other comments about possibly needing alternate wiring/plugs might also really impact which option is best. In general, it's worth using only extension chords beefy enough to take any current that the breaker won't trip on. Meaning, if the circuit is 50 amps, a 30 amp chord can become a fire hazard even if the appliance uses less. After all, not everything works perfectly all the time. Don't want one problem of a shorting drier/chord to become a much bigger problem with fire on top.

[–] [email protected] 1 points 1 day ago

Chord is a musical reference; cord is a flexible string or in this context electrical cable.

[–] [email protected] 2 points 1 day ago* (last edited 22 hours ago) (3 children)

Mmm stranded wire carries the same amount of current just fine, if not better due to the skin effect. Current likes surface area more than cross-sectional volume. 12g stranded does the same work as 12g solid. You do have to upsize for aluminum wire over copper, though - and cheap stuff will use aluminum every time.

Your final point is accurate though. Dont go using a 50a circuit for a 30a load, that's how you have a fire.

Edit: i stand corrected

[–] [email protected] 2 points 22 hours ago (1 children)

No, that's actually wrong in the case of wall power. The skin effect only appears as any significant contributer at frequencies far above normal house wiring. Furthermore, the carrying capacity of a wire (for not high frequency AC) is determined by how many charge carriers the medium can move, as in how much actual conductive metal is there. Stranded wires have less cross sectional area than solid for the same guage.

So in the right context, you'd be correct, but this isn't that case. See https://www.electricalelibrary.com/en/2021/11/17/skin-effect-what-is-it/ for some info. Notice how even 30khz has significant current flowing at depths that easily reaches the core of smaller house wiring.

[–] [email protected] 2 points 22 hours ago

Ah, fair point! Thanks.