Latest Discussions : Electrical & Lighting

gtoman

07:48AM | 02/23/09
Member Since: 02/17/05
1 lifetime posts
The outlets in my basement are on a circuit with a 20 amp circuit breaker and 12/2 sheathed electrical cable wiring. However the outlets themselves are 15 amp and not 20 amp. Is this OK?

TimBonham

02:24PM | 02/23/09
Member Since: 01/09/07
199 lifetime posts
No, it's not OK. It doesn't meet code.

The receptacles are only rated for 15A, but the circuit breaker won't trip until over 20A.

But, in the real world:

- most electrical components are designed to handle roughly double their rating. So those can probably handle 25-30A before burning up.

- this only matters if you plug in something that draws more than 15A from this receptacle (or if you get a short in it). And that's a pretty big load -- things that draw that much usually are hard-wired, not plug-in.

This situation has been around in many houses, for many years, without problems. So it isn't an emergency that you need to fix immediately.

But do fix it. All you have to do is buy 20A receptacles (about $2-$3 each) and use them to replace the existing receptacles. That's probably only 10-15 minutes of work per outlet, even for a do-it-yourselfer.

Billhart

05:02PM | 02/23/09
Member Since: 04/25/05
1915 lifetime posts
As long as there is more than one receptacle on the circuit the code specifically allows 15 amp receptacles on 20 amp circuits.

And duplex receptacles count as 2.

From the 2005 NEC.

"210.21 Outlet Devices

Outlet devices shall have an ampere rating that is not less than the load to be served and shall comply with 210.21(A) and (B).

...

(B) Receptacles

...

(3) Receptacle Ratings Where connected to a branch circuit supplying two or more

receptacles or outlets, receptacle ratings shall conform to the values listed in Table

210.21(B)(3), or where larger than 50 amperes, the receptacle rating shall not be less than

the branch-circuit rating."

Now table 210.21(B)(3) will not copy and paste, but it shows

For 15 amp circuit not over 15 amp receptacle.

And for 20 amp circuit 15 or 20 amp receptacle.

This is not code, but commentary from the NEC Handbook.

"A single receptacle installed on an individual branch circuit must have an ampere

rating not less than that of the branch circuit. For example, a single receptacle on a 20-

ampere individual branch circuit must be rated at 20 amperes; however, two or more

15-ampere receptacles or duplex receptacles are permitted on a 20-ampere generalpurpose

branch circuit. This requirement does not apply to specific types of cord-andplug-

connected arc welders."

15 amp duplex receptacles are rated at 20 amps pass through in the UL listings. And each 1/2 of the duplex is rated at 15 amps. So they can handle a 15 and 5 or 10 and 10 amp loads for example.

And if you look closely at 15 amp GFCI you will see that they are also marked 20 amps feed through.

cagy22

11:46AM | 10/27/09
Member Since: 10/26/09
1 lifetime posts
No matter how you read it , a 15 amp outlet is not allowed on a 20 amp circuit. A duplex does not count as two outlets!!! Understand the code instaed of reading into it!

Tom O

03:39PM | 10/27/09
Member Since: 09/17/02
476 lifetime posts
15 amp receptacles are definitely allowed on a 20 amp circuit. Table 210.24 summarizes the requirements nicely. Table 210.21(B)(3) also shows that a 15 amp receptacle can be installed on a 20 amp circuit that serves 2 or more receptacles. Commentary following 210.21(B)(2) in the handbook clearly states that 15 amp receptacles are permitted on a 20 amp circuit.

Please cite a code section that prohibits 15 amp receptacles on a 20 amp circuit.

BV002953

02:43PM | 01/06/14
cagy 22. Sir ... you need to understand basic electonics. The fact that you are permitted to have 15A receptacles on a 20A circuit (with a 20A breaker) is because the current draw from from the appliance plugged into that recepticle will draw no more than 15A. If you have an appliance that draws more than 15A, the plug common pin will be perpendicular to the hot pin and not fit in the 15A receptacle. Mind you, the wires (circuit) being 12 gauge, allows 20A to safely conduct if there exists a 20A outlet with a device plugged in that is capable of drawing that much current. Just because the breaker and wire are rated at 20A does not mean that much is being pushed. It all depends what you plug in. NEC does allow one duplex 15A receptacle on a 20A wire/20A breaker combo but it does not allow a singlular (non-duplex) outlet. If you only have one non-duplexed receptacle on the circuit, it must be a 20A receptacle.

BV003208

08:22PM | 02/09/14
I know this thread is old but a lot of people google search for this so I will add. BV002953 is correct. That is the logic behind why 15 amp receptacles are permitted. The pass-through part of the receptacle (what the electricity would flow through if you had more than one outlet on a circuit) is rated for 20 amps, so they are technically fine on a 20 amp circuit as long as the draw on each outlet is not >15 amps. That logic being, as BV002953 said, is that anything that draws more than 15 amps should have a 20 amp plug and thus be impossible to plug into a 15 amp outlet.

Now, of course in the real world this it is very possible, although not the norm, for the load on one outlet to exceed 15 amps. Perhaps due to someone's entire home theater being run off one outlet via a power strip. Maybe someone is using multiple high draw devices on a power strip for some reason. You can say it's then the users fault for being dumb, but at the end of the day part of the purpose of circuit breakers and such are about protecting people from things like this. 90% of people or more are not going to know they are exceeding the limits of a 15 amp outlet. Most people don't even know outlets are rated for 15 amps. Most people don't even know what an amp is. That's probably why other countries such as Canada require 20 amp outlets on 20 amp circuits. We are just making a bet that the vast majority of people won't plug a lot of stuff into a power strip. If they do, we blame the person for being dumb and not the code for allowing that ignorance to cause a fire.

Now, some people say that 15 amp outlets are exactly the same internally as 20 amp outlets and that the only difference is the shape of the plug. If this is true, then there is no risk. But if this is actually true, why is it not clearly labeled as such. Why not say 15 amp outlet rated for up to 20 amps per outlet?

BV003756

03:21PM | 04/01/14
There are tons of houses that have 15A recepticles on a 20 A main circuit. Theory is that you typically be using more than 1 outlet that each handles 15A to go to say 25AMPS then the circuit breaker blows. For me I always install 20A recepticles on a 20A breaker. If you had two thing plugged in such as a coffee pot and electric Grill you could find yourself over 15A then a meltdown and fire. Bad deal. Use 20A for 20A breakers 12 guage wire...

BV004005

11:56PM | 04/22/14
I agree, 20 amp breaker needs a 20amp outlet. 12 gauge wire. Instead of changing the outlets you could always change the breaker to a 15 amp. You'll have a heavy wire than needed, but hey, that's not a bad thing.

BV004139

06:46PM | 05/01/14
Wow... why is this so controversial?

Like the anon who said:
"Don't listen to him unless you want to burn your house down. "

People just make this bold, blanket, statements and think that they are doing the world some good. You're not, you're just being ignorant.

CLEARLY multiple people who KNOW have provided the clear answer. Yes, you CAN put a 15 amp outlet on a 20 amp circuit AS LONG AS that outlet is not the ONLY outlet on the circuit.

Yes, you can, yes, you can.. you can... can.

People have pasted code, remarks, and in-depth technical explanations on why it is how it is. Anyone else who'd like to post some "my daddy taught me", unfounded, nonsense should take another look at their professional choices.. because they're clearly not ready for the "rules and laws" system we have in place here in the U.S.

You can put 15amp outlets on a 20amp circuit as long as its not the only outlet on the circuit... Yes, you can, yes, you can.. you can... can. Positive, affirmative, yes, go, do it, go...

.. wow

BV004275

12:15AM | 05/12/14
Ok...So I'm no electrician, but I have a comment and question.

Keep all unfriendly / unhelpful comments to yourselves please.

Can 15amp outlets be hooked up to 20amp breaker AND WIRE with the same results as previously discussed in this thread? I'm asking because I already have a spool of 20 amp wire on hand but still have to purchase the breaker and outlets. I can purchase a 10pk of 15amp outlets for $3.88 at Lowe's but 1- 20amp outlet is just as much...any help is appreciated.

BV006281

04:39AM | 11/15/14
None of you must be EC's. Yo would be laughed at if you even considered the idea of not putting 15A receptacles on a 20A circuit in my area. Cheers.

jaysudo

04:44AM | 11/15/14
Member Since: 11/15/14
1 lifetime posts
BV004275: Your install should be performed by a master electrician. What's the point of adhering to code unless your work is done under a permit issued by your AHJ?

BV006618

08:10AM | 12/30/14
A 15 amp outlet is rated for 15 amp plugs, but it is also required to pass through as much as 20 amps (the pass through is the connector between the screws on either side of the outlet ... it's big enough to handle 20 amps). This way the 20 amp circuit breaker will be the first to break the circuit if the total current in the entire circuit is greater than 20 amps. That's what matters. With 15 amp (or 20 amp) outlets and at least 12 gauge wire on a 20 amp circuit breaker, the weakest element is the breaker (by design). 15 amp outlets are NOT designed for loads greater than 15 amps, but they ARE designed to carry as much as 20 amps from the rest of the circuit. BOTTOM LINE: 15 AMP OUTLETS ARE FINE IN A 20 AMP CIRCUIT AS LONG AS IT IS NOT THE ONLY OUTLET IN THE CIRCUIT.

BV006684

07:09PM | 01/06/15
I understand all of this except the part about the 15 amp cannot be the only outlet on a 20 amp circuit. Two 15 amp outlets is fine along a run, but not just one.

Why is that in the code? I could run a 12 gauge wire from a 20 amp breaker and have only 2 15 amp outlets in the entire line, and it is per code, but not just one.......

Help me understand why they specify that. Oddly, all the rest of this is clear to me after reading the thread.

Thanks

BV006769

10:49PM | 01/17/15
It's referring to single receptacles, I.e., a microwave outlet a sump pump. You install a 15A single receptacle, and code requires that to now be a 15A circuit, with a 15A breaker. It's odd, yes, but if there's only one device, and it has a 15A receptacle, it should repo when exceeding 15A, not all the way up to 20A which could melt the receptacle.

In the case of, let's say, a bedroom, you can have a 5A TV in one receptacle and a 12A vacuum in another. Neither exceeds 15A per receptacle, and with proper worrying, is perfectly fine on a 20A circuit. So when you have a line of receptacles, it's possible to go above 15A and be okay. They're giving you leeway to not have to purchase 20A restaurants for every area that you have a 20A circuit.

Hope that makes any sense.

BV006769

10:50PM | 01/17/15
I sincerely apologize for how badly autocorrect butchered that response!!

BV008642

10:28PM | 08/12/15
For what it is worth, my house built in 2005 had 0 15 amp breakers. No 14 wire either, anywhere. All outlets (other than the usual appliance 20a's) are standard 15a. All lighting fed by the 12 gauge wiring.

Ringleader

08:48PM | 11/30/15
Member Since: 11/30/15
1 lifetime posts
I think the following might help clear up this discussion. Refer to the NEMA 5 section and look at the difference between the 15 and 20 amp devices. http://www.stayonline.com/reference-nema-straight-blade.aspx. You will see that a 15 amp plug will fit a 15 or 20A recept. but a 20A plug will only fit a 20A recept. because the blades on a 15 are parallel and they are NOT on a 20, therefor you can't over load the ckt. with one device......

Retired IBEW Local 1 Wireman 37 yrs.


BV010049

11:13AM | 01/08/16
BV004139 ... your passion for the truth is appreciated and for pointing back to The Code

BV010220

05:55AM | 01/21/16
Here is a question on this subject of 15 amp outlets protected by a 20 amp breaker. If you plug in 2 space heaters in one duplex outlet (there are those people out there) what will fail first, The 15 amp outlet or the 20 amp breaker? I know the code is what is stated before, but sense should dictate that you want the "weak link" to be the breaker, not the plug or wire. For the minimal cost increase, I say put either 20 amp plugs or 15 amp breaker. Let your breaker be the "weak link".

BV010527

09:25PM | 02/15/16
Ive got to say im still not agreeing with putting a 15amp receptacle on a 20 amp breaker or 12 gauge wire.
Even with all the code posts, explanations, and scenarios, it doesnt make sense. A 15amp receptacle is rated for 15amps. Meaning internally it has metal which conducts and transmits the power to the screw which is thinner or inferior to that of a 20amp receptacle. Thus costing less money. They are made with 4 screws so they can be chained together, 2 wires come in, 2 wires go out to the next one. Those 2 wires go in, 2 wires go out to the next. So if i plug 10 amps into this one, 5 into this one, and another 5 into this one, the total current draw from the panel is 20 amps, that current is the amount that flows through the contacts of the first receptacle. Sure the wire can handle it, but how can the very first pipsqueak receptacle handle all that current?
The only way i see it being possible is if you use wirenuts and jumpers by having the incoming and outgoing wires for each outlet spliced together with jumpers going to only 2 screws. But that sounds retarded and youd still be capable of transmitting 20 amps through the internal metal parts of that duplex receptacle.

The only configuration that makes sense is what some other dude already said, 20 amp receptacles, 12 gauge wire, 20 amp breaker. No matter how you slice a 15amp, im not buying it .

Im willing to bet they know the average homeowner has no idea theres even a difference between a 15amp and a 20amp, and like a sheep, if ones cheaper than the other they will sell more of the cheaper ones, and make more money, thus why they can be bought inpacks of 10. They dont give a hoot if you burn your house down, its clearly labeled 15amps right on the box. This psychology is in every isle of the supermarket as well.

BV010528

09:28PM | 02/15/16
Ive got to say im still not agreeing with putting a 15amp receptacle on a 20 amp breaker or 12 gauge wire.
Even with all the code posts, explanations, and scenarios, it doesnt make sense. A 15amp receptacle is rated for 15amps. Meaning internally it has metal which conducts and transmits the power to the screw which is thinner or inferior to that of a 20amp receptacle. Thus costing less money. They are made with 4 screws so they can be chained together, 2 wires come in, 2 wires go out to the next one. Those 2 wires go in, 2 wires go out to the next. So if i plug 10 amps into this one, 5 into this one, and another 5 into this one, the total current draw from the panel is 20 amps, that current is the amount that flows through the contacts of the first receptacle. Sure the wire can handle it, but how can the very first pipsqueak receptacle handle all that current?
The only way i see it being possible is if you use wirenuts and jumpers by having the incoming and outgoing wires for each outlet spliced together with jumpers going to only 2 screws. But that sounds retarded and youd still be capable of transmitting 20 amps through the internal metal parts of that duplex receptacle.

The only configuration that makes sense is what some other dude already said, 20 amp receptacles, 12 gauge wire, 20 amp breaker. No matter how you slice a 15amp, im not buying it .

Im willing to bet they know the average homeowner has no idea theres even a difference between a 15amp and a 20amp, and like a sheep, if ones cheaper than the other they will sell more of the cheaper ones, and make more money, thus why they can be bought inpacks of 10. They dont give a hoot if you burn your house down, its clearly labeled 15amps right on the box. This psychology is in every isle of the supermarket as well.

BV010739

11:47AM | 03/02/16
Great discussion... IMO. Many different views. Code allows it, but some need to have their own understanding of a concept before they buy off on it.

Logically and fundamentally, you should have 20A receptacles with your 20A circuits. Does that mean you need it? No. Code says you can have a 15A receptacle as long as there is more than one on the circuit, because they are assuming that if you have more than one 15A receptacle you will have the current draw distributed to be under each receptacles individual rating. Though this is highly likely, it is still making an assumption that you will have something plugged in to BOTH receptacles to distribute the current draw to each and keep it under their 15A rating. But not only must you have something plugged into both, they must both be ON and acting as loads.

Soooo.... If you love power strips.... get a 20A receptacle.

BV011546

03:55PM | 05/07/16
I have no 20 amp receptacles in my townhouse condo and I have no 14 gauge wire or 15 amp breakers in my townhouse condo. The lowest amp breaker in the house in 20 amps. The smallest Gauge wire is 12 gauge copper. All 48 units were built the same way. Has the code changed since 2003 in Florida or were all 48 units not built to code?

BV011820

06:50PM | 06/04/16
Ok, here is an actual example...

I had a master electrician come out and wire my basement and shed. I wanted 20 amp in both places. He used 20 amp breakers, 12 guage wires and 15 amp recepticles. The shed never worked. It tripped constantly until the breaker was no good. The basement had issues too. So, my buddy came out and put in 20 amp recepticles in the shed and a third breaker (I tried replacing just the breaker at first.) Low and behold problem solved! It works perfect. Now, on his advice, I'm going to replace all 15 amp recepticles with 20 amps for this addition. After all, that is how my system is set up.

He also seems to think my basement is a death trap with the way the electrician took shortcuts to try and resolve my problems there. But that is another story.

Quite frankly - I don't trust any of you "experts" with my life. I think maybe just a couple of you know the complete physics of it all. And none of you seem to have mentioned anything that remotely describes the side effects I had with 15 amp recepticles. So, my advice to any of you reading this is to play it safe. Hire an "expert" to put in what you want and then double check everything they do and insist they are conservative. What's a few bucks per recepticle compared to months or years of problems.

And I hope this helps people who had the same problem as me.


BV011944

09:28PM | 06/13/16
Am i the only guy who has read this who just likes the stout nature of the 20amp receptacles when using them?
I found this thread because i'm having trouble finding a single pole, combination switch and receptacle rated at 20amps, and tamper proof for current code. yep, only one receptacle on the circuit, but several lights, so, not to code. Solution? I think make it a duplex box and put a duplex receptacle and a single switch.
Great thread, but geese guys, read the whole thing!

AGWashburn

07:58PM | 04/28/17
Member Since: 04/28/17
1 lifetime posts
Curve ball...3 20 amp receptacles 12/2 wiring on each circuit going to 25 amp breakers. 1 breaker per 3 boxes in my shed. Is there a 25 amp receptacle? 30 amp receptacle? I just bought the house and plan on using the shed for a wood shop where some very big machines will be running at the same time, Dust collection and so on..

Please no guess work from people reading from a book, I could do the same. Please licensed electricians only.

Thank You

P.S. I did some work with Bob when Bob and Norm were still a team in Roxbury MA.

tony

07:21PM | 07/18/17
Member Since: 07/18/17
1 lifetime posts
I have a related question. I currently have two GFCI outlets that have stamped on them 20A. They are connected to a 20 Amp Breaker. I want to replace both GFCI outlets for cosmetic reasons (backsplash remodel, etc.). My question is I cannot find 20Amp GFCI that do not have the T slot . My current ones do not have a T slot. (house about 19 years old). At one time where 20 amp GFCI made without a T slot? If I put in the new 20A T slot GFCI will a standard plug work in those.

Thanks much.

BV014324

10:55AM | 07/22/17
I am not an electrician. I rewired one of my rental houses. I put 12/2 wire from a 20 amp breaker to a 15 amp Arc Fault Indicator then to 15 amp receptacles for the bedroom and the livingroom. The inspector told me it was correct and to our code in Sacramento.

If I were to break down and hire someone to do the work for me, I surely would not hire anyone that chose to not follow code because they had a "better way" This conversation is a great example of why there is a code in the first place. That said, it is interesting reading though!

BV014348

10:43PM | 07/25/17
It might help to remember that the Code and commercial components were designed to take faults into account. For example, an approved 15 amp receptacle MUST be designed to carry enough current to trip the 20 amp breaker without self destructing. The reason this is possible is because it is designed to carry 15 amps 'forever'. A fault condition is a short term thing and wires and metals can carry currents much higher in these conditions; they don't have time to degrade before the trip occurs.
As an obscure example, there is a place in the code which specifically allow 12 gauge wire (normally thought to be good for 20 amps) to carry 50 amps during a trip condition (tapping rule, table 210.24). Note that 12 gauge wire is not ALWAYs ok for a load of 20 amps; it must be derated in many situations.
A familiar form of this is a typical lighting fixture. I believe you can actually have 18 gauge wire connected to a 20 amp branch circuit depending on the lights involved.
A more refined view of the code will lead to a whole slew of counter-intuitive revelations, all of which have been well thought through by some very bright people. With all due respect, it is very difficult to apply 'reason' to the Code without formal training.

BV014509

02:34PM | 08/15/17
Yup!

BV015880

01:58PM | 03/09/18
yeah but....but..

BV016191

05:29AM | 04/20/18
Building / Electrical code are there for safety, Please use the correctly rated receptacle for proper circuit. Electricity is safe when you respect its power. Just think if we were using old methods of electrification of homes. How many house fires will we have and the loss of life. It amazing how few extra dollars for a GFCI receptacle near wet saves life. Don’t put money before life. It may be you home today, but someday it maybe you grand children, Being burn in fire or shock by live circuit is not great thing to experience. We can now all sleep soundly at night. Because of code we have fire alarms to wake us if the unthinkable happens. Don’t foolish because it’s few bucks less.

BV016493

03:58PM | 05/31/18
Sorry, you can't!! It is possible to put a 15 amp male plug on an extension cord (with #12 AWG wires) and then use that extension cord for something that draws more than 15 amps. The receptacle is rated for 15 amps only so it will eventually burn up. The 20 A let through that some people mention is not for continuos amperage.

BV017297

09:11PM | 09/01/18
Well, BV010528 (13th replies back) answered his own question on how the first pipsqueak receptacle can handle all the combined load. It can't and it doesn't have to! Draw from a 20amp C/B through 12/2 wire goes to the first receptacle's screws and through the external jumper to the next screw on the duplex receptacle and then on to the next receptacle's screw and external jumper, etc., etc., etc.

(Hence, the total power drawn on the circuit is not handled by the internal components of the first receptacle, it is bypassed around the receptacle by the jumpers on the sides.)

Yes, the total circuit draw is handled by the wiring collectively at each receptacle heading back to the C/B but each receptacle itself (internally) is only handling its own load. The jumpers on a 15 amp receptacle are the same size as the jumpers on a 20 amp receptacle.

And agreed, if someone plugs a 15amp power strip (with five 10 amp devices on it) into a 15 amp receptacle, I'm betting the power strip smokes before the C/B trips.

Hope that explains that 'rabbit trail' of the discussion.

BV017834

11:16PM | 10/30/18
I was changing out some receptacles recently because the ones I had are 25 years old. I am not an electrician but I have been watching tutorials made by certified electricians (Sparky Channel on YouTube is great). So I have learned the very basics of home wiring and feel comfortable doing basic stuff like this.

Anyway, I found the circuit that runs to my kitchen counter. The best I can tell, it only powers 3 receptacles. When I go to the breaker box, the circuit is listed as 20A (clearly marked). I have read that 20A is common for kitchen counters (code I believe nowadays). Also, none of my kitchen receptacles were GFCI's, so I went out and bought a 20A GFCI and a couple regular 20A receptacles.

However, when I went to change out the receptacles, I noticed the wire is 14 gauge. I am the original owner and I have never had anyone except certified electricians do any work on my home wiring, so whoever put that breaker there did it knowing 14 gauge wire was in the circuit.

So now I have 20A receptacles, a 20A breaker and 14 gauge wire. My home is from the mid 90's, so I don't know if code was different back then (I doubt it). In any case, receptacles are cheap, but GFCI's aren't. I have no spot for that 20A GFCI anywhere else because every other circuit is 15A. Should I just take a hit and toss it and put 15's in?

BV017947

06:36PM | 11/12/18
For safety I would remove the 20A breaker and switch to a 15A because of the 14 gauge wire. I would eventually upgrade the wire to 12 gauge to meet current codes then you could reinstall the 20A breaker.


Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply choose button

Anonymous

Post new button or Login button
Register