# 20 amp breaker for 15 amp devices



## matt1124 (Aug 23, 2011)

We can use 12 AWG wire protected by a 20 amp breaker to feed 15 amp duplex receptacles because since they are duplex, that would be considered multiple outlets, correct?

Could we feed 10 AWG wire protected by a 30 amp breaker to feed 15A duplex receptacles?


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## MechanicalDVR (Dec 29, 2007)

12ga on 20 amp breaker with 15 amp devices, all the time all day long.

10ga on 30 amp breaker with 15 amp devices, the wire is fine but not the amperage.


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## matt1124 (Aug 23, 2011)

MechanicalDVR said:


> 12ga on 20 amp breaker with 15 amp devices, all the time all day long.
> 
> 10ga on 30 amp breaker with 15 amp devices, the wire is fine but not the amperage.


How about we bump the devices on the 10 AWG wire protected by 30 amps to 20 amp duplex recepts?


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## MechanicalDVR (Dec 29, 2007)

matt1124 said:


> How about we bump the devices on the 10 AWG wire protected by 30 amps to 20 amp duplex recepts?


Bigger question is why would you want to?


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## matt1124 (Aug 23, 2011)

For a dedicated circuit for a treadmill that trips an AFCI. If 210.12 only covers 15 and 20 amp circuits for AFCI, why can I not just pull #10 and work around it?


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## RePhase277 (Feb 5, 2008)

Negative on the 30 amp.The reason is, even 15 amp receptacles are rated to carry 20 amps. But neither 15 nor 20 amp devices are rated for 30 amps.


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## emtnut (Mar 1, 2015)

matt1124 said:


> For a dedicated circuit for a treadmill that trips an AFCI. If 210.12 only covers 15 and 20 amp circuits for AFCI, why can I not just pull #10 and work around it?


Not sure whether to laugh, cry, or scream TROLL !!!!!!

:laughing:


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## RePhase277 (Feb 5, 2008)

If you're going to violate the code, using a regular breaker instead of an AFCI is better than using a 15 amp receptacle on a 30 amp breaker.


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## MechanicalDVR (Dec 29, 2007)

So if I follow your logic, it's better to smoke the treadmill than find the problem with the circuit for the machine?


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## matt1124 (Aug 23, 2011)

Half troll, half serious. We got to talking about AFCI at the shop and thought up this idea. The treadmill is long gone at this point, it just got a regular breaker.


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## emtnut (Mar 1, 2015)

matt1124 said:


> For a dedicated circuit for a treadmill that trips an AFCI. If 210.12 only covers 15 and 20 amp circuits for AFCI, why can I not just pull #10 and work around it?


If you get a really really big treadmill, with a 14-30P that would totally work:thumbsup:


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## MechanicalDVR (Dec 29, 2007)

emtnut said:


> If you get a really really big treadmill, with a 14-30P that would totally work:thumbsup:


I've never seen one for this load but they are made and installed:


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## splatz (May 23, 2015)

It doesn't feel right but would this solve it?


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## emtnut (Mar 1, 2015)

Or this ?










Might be a tad more that 30A thou :blink:


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## MechanicalDVR (Dec 29, 2007)

emtnut said:


> Or this ?
> 
> 
> 
> ...


Yeah boy, that looks more like a 2 pole 60 from here! LOL!


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## RePhase277 (Feb 5, 2008)

emtnut said:


> If you get a really really big treadmill, with a 14-30P that would totally work:thumbsup:


For 120 volts it would be 5-30P.

A 120/240 volt treadmill.... they call those "escalators" I think.


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## RePhase277 (Feb 5, 2008)

splatz said:


> It doesn't feel right but would this solve it?


It would work for going from 30 amps down to 15, but it is still a 15 amp, 120 volt receptacle subject to the AFCI requirements.


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## emtnut (Mar 1, 2015)

RePhase277 said:


> For 120 volts it would be 5-30P.
> 
> A 120/240 volt treadmill.... they call those "escalators" I think.



I was one of those kids that always pressed the emergency stop on escalators :jester:


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## matt1124 (Aug 23, 2011)

Can multiple "heavy duty lampholders" be put on a 30 amp circuit?


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## RePhase277 (Feb 5, 2008)

matt1124 said:


> Can multiple "heavy duty lampholders" be put on a 30 amp circuit?


Not in a fat woman's house.


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## MechanicalDVR (Dec 29, 2007)

matt1124 said:


> Can multiple "heavy duty lampholders" be put on a 30 amp circuit?


Why does it seem you may have gotten a great buy on a pallet box of 30 amp SP breakers?


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## matt1124 (Aug 23, 2011)

Haha just think it would be funny for the inspector to roll up for final and just have 30 amp traditional breakers and no AFCI on a new house. 

One supply house around here has 30, 40, and 50 amp single pole plug on BR breakers and they are sure dusty!


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## five.five-six (Apr 9, 2013)

Why not use a 30 amp receptacle and change the cord cap on the appliance?


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## backstay (Feb 3, 2011)

five.five-six said:


> Why not use a 30 amp receptacle and change the cord cap on the appliance?


You know why!


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## matt1124 (Aug 23, 2011)

five.five-six said:


> Why not use a 30 amp receptacle and change the cord cap on the appliance?





backstay said:


> You know why!


How many amps does your flat panel TV need? You surely don't plug that into a 20 amp protected circuit, _do you_?


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## B-Nabs (Jun 4, 2014)

five.five-six said:


> Why not use a 30 amp receptacle and change the cord cap on the appliance?


Put a 15A inline fuse in there and you're golden!


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## RePhase277 (Feb 5, 2008)

It would be fun to walk an inspector around a new house with only 5-30R receptacles everywhere, and low-voltage lighting, skirting all the AFCI requirements.:laughing:

If you had power strips with the 30 amp cord caps and 15 amp fuses or breakers, I think you could manage to get by.


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## matt1124 (Aug 23, 2011)

RePhase277 said:


> It would be fun to walk an inspector around a new house with only 5-30R receptacles everywhere, and low-voltage lighting, skirting all the AFCI requirements.:laughing:
> 
> If you had power strips with the 30 amp cord caps and 15 amp fuses or breakers, I think you could manage to get by.


"Dammit, there's like five you guys that pull this crap. Here's your freakin' sticker!"


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## Barjack (Mar 28, 2010)

RePhase277 said:


> It would be fun to walk an inspector around a new house with only 5-30R receptacles everywhere, and low-voltage lighting, skirting all the AFCI requirements.:laughing:
> 
> If you had power strips with the 30 amp cord caps and 15 amp fuses or breakers, I think you could manage to get by.


Would it still be fun when he red tags you?


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## RePhase277 (Feb 5, 2008)

Barjack said:


> Would it still be fun when he red tags you?


It would be worth it.


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## foothillselectrical (Mar 17, 2013)

MechanicalDVR said:


> I've never seen one for this load but they are made and installed:


Is that Oprah?


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## MechanicalDVR (Dec 29, 2007)

foothillselectrical said:


> Is that Oprah?


Rosie! On the machine Michael Moore out grew!


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## DaveBall71 (Mar 1, 2017)

I have similar situation: I have run a direct-buried 30A, 120V circuit from my Main panel to an above grade outdoor junction box 100 feet from my house. Its for a small outbuilding that won't be delivered for another 4 weeks. The 10-2 UF cable is coiled up in the box, with wire nuts on end, and the 1P-30A breaker is off. 

Meanwhile, I'd like to install an outdoor 20A receptacle about 50ft away from the junction box to supply a small water fountain pump for a garden my wife has installed. Can I use #12 and somehow tap off the 30A circuit without a 20A OCPD? The outbuilding will come with a small loadcenter but the wife cant seem to wait.


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## Bird dog (Oct 27, 2015)

DaveBall71 said:


> I have similar situation: I have run a direct-buried 30A, 120V circuit from my Main panel to an above grade outdoor junction box 100 feet from my house. Its for a small outbuilding that won't be delivered for another 4 weeks. The 10-2 UF cable is coiled up in the box, with wire nuts on end, and the 1P-30A breaker is off.
> 
> Meanwhile, I'd like to install an outdoor 20A receptacle about 50ft away from the junction box to supply a small water fountain pump for a garden my wife has installed. Can I use #12 and somehow tap off the 30A circuit without a 20A OCPD? The outbuilding will come with a small loadcenter but the wife cant seem to wait.


Call an electrician Mr Engineer.


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## Dennis Alwon (May 9, 2009)

Bird dog said:


> Call an electrician Mr Engineer.


I sent a pm....


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## lightman (Oct 14, 2015)

I've seen times that a 30 amp breaker was needed for some power tools. Things like table saws and radial arm saws with 15 amp plugs will often trip 20 amp breakers, even when on dedicated circuits. What do ya do? Nothing that I can think of is legal.


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## emtnut (Mar 1, 2015)

This is the first thread on ET that has left me speechless :001_huh: ..... That doesn't happen often :no:

Cheers :drink:


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## Dennis Alwon (May 9, 2009)

A 30 amp circuit must have 30 amp receptacles. Table 210.21(B)(2) & Look at table 210.21(B)(3) also


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## RePhase277 (Feb 5, 2008)

lightman said:


> I've seen times that a 30 amp breaker was needed for some power tools. Things like table saws and radial arm saws with 15 amp plugs will often trip 20 amp breakers, even when on dedicated circuits. What do ya do? Nothing that I can think of is legal.


There's a couple of things that might work. The circuit might be too long, causing excessive voltage drop and the tool draws more amps. The fix would be to use a larger wire. If that doesn't work, you can get breakers called "High Magnetic" to handle large inrush currents.


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## emtnut (Mar 1, 2015)

lightman said:


> I've seen times that a 30 amp breaker was needed for some power tools. Things like table saws and radial arm saws with 15 amp plugs will often trip 20 amp breakers, even when on dedicated circuits. What do ya do? Nothing that I can think of is legal.


btw .. My comment wasn't directed at you 

I haven't ever seen a problem like that with a radial arm saw... but I have seen old table saws, that had a motor with shot bearings that drew too much power to get them spinning .


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## emtnut (Mar 1, 2015)

RePhase277 said:


> There's a couple of things that might work. The circuit might be too long, causing excessive voltage drop and the tool draws more amps. The fix would be to use a larger wire. If that doesn't work, you can get breakers called "High Magnetic" to handle large inrush currents.


I approve of the new avatar :thumbsup:

I've seen the 'gif' ... I like the last part better, but it'll do :brows:


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## scotch (Oct 17, 2013)

RePhase277 said:


> It would work for going from 30 amps down to 15, but it is still a 15 amp, 120 volt receptacle subject to the AFCI requirements.


You can get Marine adapters for 30A twist-lok to 15A....boaters use them at the shore power outlets here !


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## telsa (May 22, 2015)

RePhase277 said:


> It would be fun to walk an inspector around a new house with only 5-30R receptacles everywhere, and low-voltage lighting, skirting all the AFCI requirements.:laughing:
> 
> If you had power strips with the 30 amp cord caps and 15 amp fuses or breakers, I think you could manage to get by.


By your GIF, you've found somebody to lift a finger. 

Lucky guy.


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## lightman (Oct 14, 2015)

emtnut said:


> This is the first thread on ET that has left me speechless :001_huh: ..... That doesn't happen often :no:
> 
> Cheers :drink:


Your right, it does not happen often. But when it does it makes the electrician look bad. My own table saw would do this is you hit a knot, cut treated plywood that was wet or just crowded it too fast. I converted it to 240 volts and the problem went away. The connivence of using 120 volts also went away. Not a problem for me in my shop but still a possible inconvenience to others. I've used control breakers that had trip curves but I'm not familiar with anything you can do with a QO or equivalent breaker. Maybe a 20 amp receptacle, a #10 wire, a 30 amp breaker and look the other way? An unusual problem? Yeah, for sure! What do ya do? I'll look into the high magnetic breakers.


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## emtnut (Mar 1, 2015)

lightman said:


> Your right, it does not happen often. But when it does it makes the electrician look bad. My own table saw would do this is you hit a knot, cut treated plywood that was wet or just crowded it too fast. I converted it to 240 volts and the problem went away. The connivence of using 120 volts also went away. Not a problem for me in my shop but still a possible inconvenience to others. I've used control breakers that had trip curves but I'm not familiar with anything you can do with a QO or equivalent breaker. Maybe a 20 amp receptacle, a #10 wire, a 30 amp breaker and look the other way? An unusual problem? Yeah, for sure! What do ya do? I'll look into the high magnetic breakers.


Take a look here ... http://www.graybar.com/store/en/gb/...duty-rated-miniature-circuit-breaker-88242631


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## matt1124 (Aug 23, 2011)

emtnut said:


> Take a look here ... http://www.graybar.com/store/en/gb/...duty-rated-miniature-circuit-breaker-88242631


Ooh, and that's switch duty rated too. Lots of people love to turn off things at the breakers at night at closing time. I'll have to remember such a thing exists


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## lightman (Oct 14, 2015)

That would be worth a try. And I use Graybar for my supplier!


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