Originally Posted by kraut
Your referring to a single outlet branch circuit only states that the receptacle shall not be less then the rated branch circuit, however that does not permit your interpretation of usage of a higher rated receptacle, making possible the use of appliances that are over sized for the circuits capacity. By your logic that would permit the installation of any higher rated receptacle as long as it is not below the stipulated matching amperage. A really ridiculous interpretation - I am by your logic permitted to install an 100Amp arc-tight outlet to a 15 amp singly terminated circuit?
Your advice should be eliminated from the posting as they are a clear code violation by someone who cannot read what the code states.
It is dangerous to anybody and potentially a life threatening fire-hazard. You are a nincompoop, dear sir.
I am not an electrician but I did low voltage course work and hold a supplementary ticket to the gas ticket to wire gas fired heating appliances and I have worked in industrial camps with connections up to 100 Amps.
Let me start by saying that your concern for the safety of members is noted and heartfelt, the jab at my IQ notwithstanding
You say that what I suggested is a clear code violation. The code uses three different types of specifications: minimum, maximum and specific (i.e. the one and only thing accepted). In this case, the specification sets a minimum standard and no maximum. It would be like building code saying I post has to be 2x4 and I put in 2x6. There is no code violation. My recommendation matches the code word for word. Using 20 amp outlet on 15 amp circuit is fully compliant with the code.
Your interpretation is just that, an interpretation that even though the code is setting a minimum, in really it is setting at a specific value, i.e. the circuit capacity. You say my answer is dangerous and life threatening but you don’t explain the theory behind that and the specifics in this situation. So let’s parse it on our own. I welcome your comments.
I imagine your concern stems from the fact that if there is a 20 amp outlet on a 15 amp circuit, someone can plug in an appliance that can exceed that rating. As I noted in the table I posted from NEC, this is clearly allowed for 40 amp circuits:
The 40 amp circuit is clearly allowed to have a 50 amp outlet. For the code to be so specific here, clearly there is no danger in having an outlet that exceeds circuit’s current rating.
It is not like the 15 amp outlets protect the circuit from over current in that manner anyway. Personal example: in one our bedrooms we have five duplex outlets on the same circuit. That is 10 outlets total. Let’s say I plug in a 10 amp vacuum and a 12 amp space heater in another. So now the total is 22 amps. Are you saying that I am going to have a fire? Remember, I have 8 other outlets to still plug things into! So the opportunity to overload a circuit is ample even with 15 amp outlet.
The code allows that many outlets on one circuit and with it, implicitly accepts that you can pull way more current out of that circuit than it is designed to do. If your worry is right, then they would have to limit you to a single outlet since any more than that would allow the homeowner to exceed what the circuit is designed to feed.
Let’s look at what you are recommending and see if that is a “safe” thing given your concern. We have a 15 amp circuit breaker and 14 gauge wire connected to a 15 amp outlet. Now imagine someone plugging in an appliance that has a dead short in it. The amount of current it takes to vaporize and open that short could be enormous – way more than the 15 amps rating of the circuit. Do we have a hazard now? Of course not. The breaker’s job is to provide current limiting to protect the downstream portions of the circuit. It will trip in a second or less (hopefully much less) during which the wiring *will* be subjected to the much increased load and hence heat rise. The wire will not be allowed to reach the temperature at which it will catch on fire or pose any safety risk because the breaker will pop after that short period. This scenario is one of the key ones the code intends to protect the homeowner from. We can't stop the homeowner from creating a short. But we can avoid that causing a fire. If we have protection against such high amount of current, the difference between a 15 and 20 amp outlet/usage is surely covered just the same.
So to answer your question, yes, if there were a 100 amp outlet that was designed for 120 volt operation you could indeed use that. It will tolerate a lot more abuse than the 15 amp and be the strongest link in the chain.
Note that your local municipality may have different rules than what the national code mandates. In your case you live in Canada so the CEC would be your concern, not the US NEC. The treatment may be different there.
So in short, there is no safety risk here. If you can identify it, I am happy to be convinced otherwise