# Outlets - 14-2 or 12-2?



## jonathan03

I'm about to rewire everything and I want to be sure its ok to wire outlets with 14-2? 14-2 takes up to 15 A and the standard outlets home depot sells are only rated to 15 A. So I figured that using 12-2 (20 A ) wire is just a waste of money. Outlets are only good to 15 A and more current would just melt the outlet (worst case all power in one outlet), even if the wire could take it. 

I guess there is the assumption that people won't use all 15 A in each outlet but there is the always some moron who will plug an electric lawnmower, a shop vac, and a hair dryer all in one outlet. 

Anyway, some people told me to use 12-2 for outlets but my electrician friend said 14-2 is fine. I don't see the benefit of using 12-2. If you use a 20 A breaker the outlet is only good to 15 A and someone could overload it and melt it. For safety sake, I think it should be a 15 A breaker and 14-2 wire. Is there another reason to use 12-2?


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## thefatpigeon

In canada in the allowable ampacity for 14 gauge wire is 15 amps. In canada you can design circuits for 80 percent. 80 percent is 12 amps. each outlet( receptacle, light) is roughly one amp so you can use 14-2 wire to 12 outlets protected by a 15 amp breaker. however if you use 12-2 you can use t-rated 20 amp receptacles however in my code you only generally see those in kitchens due to number of appliances. you are perfectly safe to use 14-2 wire as long as you circuit doesn't exceed 80 percent> these numbers are taken from the CEC 2010 edition. I am pretty sure we are equivalent when it comes to allowable ampacities for wire.


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## thefatpigeon

by the way using 120/240 voltage which is common in residention 15 amps would be 1800 watts. p=EI You would be pretty hard to find a plug in appliance that would use that amount of power so you don't have to worry about melting the receptacle. The main worry is heating up the copper wiring in your house. to answer another quesiton is if you want to add more outlets onto a circuit you may use 12 gauge wire. In almost all commercial jobs they spec out 12 gauge wire for 120/208 V even though the allowable ampacity states 14 is enought. the engineers most likely due this to prevent line drops in voltage over long distances and because buisness tend to run appliances all day.


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## frenchelectrican

In usa side to use the 15 amp duplex rececptale it is not a issue at all due they do share the same guts { inside parts } as 20 amp verison so they are rated to handle that however if you have singleplex now the bet is off.


The other thing is between the 2.5mm² and 4.0mm² { 14 AWG and 12 AWG } all it depending on that circuit if all are on 2.5mm² then you have to use 15 amp breaker now if you are on 4.0mm² you can use either 15 amp or 20 amp { the only way you can able use full 20 amp if you have entire circuit is wired with 4.0mm² } 

Just think like weak link in the chain if one link is smaller then the rest it will snap before the larger link will snap it the same idea with conductors.

Merci,Marc


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## secutanudu

If you're wiring new outlets, i'd use 20A and 12/2 wiring. You never know what you might plug in.


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## darren

thefatpigeon said:


> In canada in the allowable ampacity for 14 gauge wire is 15 amps. In canada you can design circuits for 80 percent. 80 percent is 12 amps. each outlet( receptacle, light) is roughly one amp so you can use 14-2 wire to 12 outlets protected by a 15 amp breaker.


This does not mean you get 16 outlets on a 20A breaker, your still only allowed 12 outlets.


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## brric

darren said:


> This does not mean you get 16 outlets on a 20A breaker, your still only allowed 12 outlets.


Not in the USA.


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## Daniel Holzman

The following comments apply to the US only. You can have as many outlets on a run as you like. The outlets are protected by the circuit breaker or fuse. The circuit breaker or fuse is sized for the WIRE size, therefore for a 14 gauge wire run you must use a 15 amp breaker. Since the standard grade outlet is rated for 15A, your breaker protects the outlet and the wire, so there is no chance you will melt the outlet.

For 12 gage wire, you can use either a 15A breaker or a 20A breaker. Even if you use a 20A breaker with standard grade outlets, you are not going to melt the outlets, since even though they are rated for only 15A, they can all pass 20A through, and the internals (as previously noted) are good for 20A, just not rated for it. For about $4, you can buy contractor grade outlets that are rated for 20A, and come with the T style plug. That is what I use in my house, costs a few extra bucks, but I can plug a heavy duty appliance, Shop Vac, compressor etc in without any concerns.


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## Blockisle9

You can use 15 amp receptacles on a 20 amp circuit as long as there’s multiple outlets. A duplex receptacle is considered multiple.
I would use 20 amp though.


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## Wiredindallas

Welcome, Blockisle9.
As a reminder to us all, remember to check the 1st post date. No problem, just that you are directly helping out the OP.


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## Wiredindallas

That's NOT helping out……..


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## Blockisle9

Wiredindallas said:


> Welcome, Blockisle9.
> As a reminder to us all, remember to check the 1st post date. No problem, just that you are directly helping out the OP.


I always said I would always check the date. Broke my own rule… lol sorry


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