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Want recommendation for quality 5-20 male to 5-15 male adapter to use with 15 Amp circuit/12A load

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Xebec

Member
Mar 20, 2019
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I'll be doing some traveling, and would like to use one extension cord for either 120V/15A or 120V/20A charging. However, the male end on the 5-20 extension cord of course won't fit in a 5-15 wall socket.

I'd like to use a cheap 5-20 to 5-15 adapter in case I end up at a location with a 5-15 wall plug, and my 5-15 Mobile Connector plug isn't long enough.

Any recommendations for a specific adapter that'll be happy with 12A continuous load?

I was looking at this cheap one (below) , but I know some of you may have experiences here to share. Thanks.

 
One problem: if you plug in a NEMA 5-20 Gen 2 adapter with your UMC into the 5-20 socket of the extension cord AND you are plugging into a standard 5-15 (15A) wall outlet, then you'll have to manually reduce the charging current to 12A.
 
One problem: if you plug in a NEMA 5-20 Gen 2 adapter with your UMC into the 5-20 socket of the extension cord AND you are plugging into a standard 5-15 (15A) wall outlet, then you'll have to manually reduce the charging current to 12A.
Actually no. NEC allows 15amp outlets on 20amp circuits. Most houses have 20amp plug circuits. If the breaker is a 20amp, but the plugs are 15amp, you can easily use a 5-15 -> 5-20 adapter. Drop by Home Depot and you can build an adapter for about 12 bucks
1 x Leviton 20 Amp 125-Volt 3-Wire Connector, Yellow Model #R00-520CV-00Y. $4.98
1 x Leviton 15 Amp 125-Volt 3-Wire Plug, Orange Model #R51-515PV-0OR $3.51
2 x Southwire (By-the-Foot) 12/3 600-Volt CU Black Flexible Portable Power SOOW Cord $4.10
$12.59 + local tax if you need to buy/built it ASAP.

or hop on amazon


and get a pre-built adapter for $6.88

The worst case is you blow a breaker, lower the charge rate, and reset the breaker.
 
Actually no. NEC allows 15amp outlets on 20amp circuits. Most houses have 20amp plug circuits. If the breaker is a 20amp, but the plugs are 15amp, you can easily use a 5-15 -> 5-20 adapter. Drop by Home Depot and you can build an adapter for about 12 bucks
1 x Leviton 20 Amp 125-Volt 3-Wire Connector, Yellow Model #R00-520CV-00Y. $4.98
1 x Leviton 15 Amp 125-Volt 3-Wire Plug, Orange Model #R51-515PV-0OR $3.51
2 x Southwire (By-the-Foot) 12/3 600-Volt CU Black Flexible Portable Power SOOW Cord $4.10
$12.59 + local tax if you need to buy/built it ASAP.

or hop on amazon


and get a pre-built adapter for $6.88

The worst case is you blow a breaker, lower the charge rate, and reset the breaker.
Thanks for correcting me. I just checked my panel and it seems like all my 120V 15A breakers are assigned to lights in my house; none to outlets. The outlets are on 20A breakers but they all appear to have 5-15 sockets. I can't find any 5-20s, even in my garage where I would think they would mostly be used.
 
Thanks for correcting me. I just checked my panel and it seems like all my 120V 15A breakers are assigned to lights in my house; none to outlets. The outlets are on 20A breakers but they all appear to have 5-15 sockets. I can't find any 5-20s, even in my garage where I would think they would mostly be used.

/shrug.... My home, which was built in 2008 and is 3300 square feet, has most of the outlets on 15 amp circuits, not 20. @smatthew, why is the expectation that "most homes have 20amp circuits for outlets"?
 
My 1980 home has all the 15A outlets on 20A breakers. I’m guessing that the intention was to reduce nuisance tripping when someone plugged the 12A vacuum into the same circuit as the 3A TV, the 2A refrigerator, and the 2A floor lamp.

Perhaps your builder decided that installing more circuits was better or cheaper than using 12 gauge wire everywhere.
 
One problem: if you plug in a NEMA 5-20 Gen 2 adapter with your UMC into the 5-20 socket of the extension cord AND you are plugging into a standard 5-15 (15A) wall outlet, then you'll have to manually reduce the charging current to 12A.

Actually no. NEC allows 15amp outlets on 20amp circuits. Most houses have 20amp plug circuits. If the breaker is a 20amp, but the plugs are 15amp, you can easily use a 5-15 -> 5-20 adapter.

Even with an adapter, the charging current must still be reduced to 12A.

It's spelled out in the NEC: Table 210.21(B)(2) "Maximum Cord-and-Plug Connected Load to Receptacle".
For a receptacle with a 15A rating, regardless of whether the circuit rating is 15 or 20A, the maximum cord-and-plug connected load is 12 amps.

It's permissible to put 15A receptacles (plural) on a 20A branch circuit. But you shouldn't pull >12A through a 15A rated receptacle, as that isn't what it was designed or tested for.

The worst case is you blow a breaker, lower the charge rate, and reset the breaker.
No, the worst case is an electrical fire, which could be catastrophic. The breaker won't help you here, because you're overloading the receptacle itself, not the house wiring or the breaker. The receptacle contacts and housing are the weakest link.
 
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