Single receptacle question

[mark32]

Would the following statements be corrrect:

Dedicated 15a line - a 15a or 20a single rec can be used
Dedicated 20a line - only a 20a single rec can be used

 

[david luchini]

Why not a single 30A receptacle on a dedicated 15A or 20A branch circuit? Etc.

 

[480sparky]

210.21(b)(1).

 

[ASG]

Would the following statements be corrrect:

Dedicated 15a line - a 15a or 20a single rec can be used
Dedicated 20a line - only a 20a single rec can be used

I'd say the reverse. Only a 15A receptacle can be used on a 15A circuit but a 20A circuit can have a 15A or 20A receptacle as per the table.

 

[david luchini]

I'd say the reverse. Only a 15A receptacle can be used on a 15A circuit but a 20A circuit can have a 15A or 20A receptacle as per the table.

No, this is incorrect. A single receptacle on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.

So a single 15A receptacle can't be installed on a 20A individual branch circuit.

 

[Dennis Alwon]

I'd say the reverse. Only a 15A receptacle can be used on a 15A circuit but a 20A circuit can have a 15A or 20A receptacle as per the table.

Not quite-- the op did state single recep.

210.21(B) Receptacles.
(1) Single Receptacle on an Individual Branch Circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.

 

[infinity]

Would the following statements be corrrect:

Dedicated 15a line - a 15a or 20a single rec can be used
Dedicated 20a line - only a 20a {or larger} single rec can be used

Although it seems counter intuitive, both statements are true. This is common with a 40 amp residential range circuit and a 50 amp single receptacle.

 

[Greg1707]

confusing section of code

confusing section of code

I find this section of the code to be needlessly confusing. Has there been any discussion about revising this section to simply state that the amperage of the receptacle must match the amperage of the circuit? With this simple revision an entire section of the code could be deleted!

 

[augie47]

I vote with Rob

 

[480sparky]

...... Has there been any discussion about revising this section to simply state that the amperage of the receptacle must match the amperage of the circuit? ..........

You wanna start installing 20a GFCIs and receptacles in your bathrooms, kitchens, dining rooms, breakfast nooks, etc.? If so, where do you buy toasters & coffee makers and mixers that have 20a cord caps on them?

 

[charlie b]

You wanna start installing 20a GFCIs and receptacles in your bathrooms, kitchens, dining rooms, breakfast nooks, etc.? If so, where do you buy toasters & coffee makers and mixers that have 20a cord caps on them?

Now perhaps it is I who is confused. I thought the construction of a 20 amp receptacle allowed the insertion of either a 15 or 20 amp cord cap, but construction of a 15 amp receptacle allowed the insertion of only the 15 amp cord cap. Do I have that backwards?

 

[charlie b]

I find this section of the code to be needlessly confusing.

Oh, I am sure that can't be the case! Sure the code language is confusing from time to time, but I have to believe it is necessary. I mean, safety is at stake! :roll:

 

[gary]

I also agree with Rob, but think it would be unwise to put a 20 amp single receptacle on a dedicated 15 amp circuit. Although apparently allowed by 210.21(b)(1), a 20 amp single receptacle on a 15 amp circuit would not be able to supply the power required by a device with a 20 amp plug without potentially overloading the circuit.

 

[480sparky]

Now perhaps it is I who is confused. I thought the construction of a 20 amp receptacle allowed the insertion of either a 15 or 20 amp cord cap, but construction of a 15 amp receptacle allowed the insertion of only the 15 amp cord cap. Do I have that backwards?

You are correct. So what is to be gained by installing 20-a devices when you will only be inserting 15-a cords?

 

[infinity]

I also agree with Rob, but think it would be unwise to put a 20 amp single receptacle on a dedicated 15 amp circuit. Although apparently allowed by 210.21(b)(1), a 20 amp single receptacle on a 15 amp circuit would not be able to supply the power required by a device with a 20 amp plug without potentially overloading the circuit.

Yup that's true. So it would be up to the OCPD to protect the circuit conductors. In the example I cited you would still need to use a 50 amp receptacle on a 40 amp range circuit in a dwelling because the 50 amp is a standard size for a range cord.

 

[david luchini]

You could put a single 50 amp receptacle on an individual 15A branch circuit if you wanted to. But then again, why would you want to.

 

[jetlag]

You are correct. So what is to be gained by installing 20-a devices when you will only be inserting 15-a cords?

I use the 20 a rec when replacing a burned rec where floor heaters, irons, fry pans etc have been used . The 15 amp cord fits much tighter and the rec wont burn as easily

 

[jetlag]

I use the 20 a rec when replacing a burned rec where floor heaters, irons, fry pans etc have been used . The 15 amp cord fits much tighter and the rec wont burn as easily

ON this post I was refering to installing 20 a rec on a 20 circuit. No matter what code says I dont believe a 20a rec should be installed 15 a circuit. The reason is a 15a circuit should only be loaded to 12 a and a 20 a cord could be used to draw 15a and not trip the breaker. But thats just me I guess one would argue that 15a would not hurt the condutors unless they are derated.

 

[Greg1707]

confusing section of the code

confusing section of the code

Ok, my idea of simplifying this section of the code was shot down. But let me ask this question. Why do we allow 15 amp receptacles to be installed on 20 amp circuits? Because 15 amp receptacles are cheaper? Why not just require 15 amp receptacles for 15 amp circuits? 20 amp receptacles for 20 amp circuits etc. ? With this system one could tell by looking at the receptacle what the amperage of the circuit would be.

 

[hurk27]

Ok, my idea of simplifying this section of the code was shot down. But let me ask this question. Why do we allow 15 amp receptacles to be installed on 20 amp circuits? Because 15 amp receptacles are cheaper? Why not just require 15 amp receptacles for 15 amp circuits? 20 amp receptacles for 20 amp circuits etc. ? With this system one could tell by looking at the receptacle what the amperage of the circuit would be.

Because 15 amp receptacles are feed through rated for 20 amps, and why would you ever need a receptacle with a 20 amp configuration as most all equipment only has a 15 amp plug on it, the few pieces of equipment that do have a 20 amp plug will most likely require a dedicated circuit, or if it is even plugged into a 20 amp circuit with other loads guess what it will trip the breaker. the brass busses inside of a 15 amp receptacle are the same as the ones in a 20 amp receptacle of the same type and style, now if you want to spend more of the home owners money and upgrade to all commercial grade receptacles then were talking a whole different ball game.