Quote to add an outside electrical outlet

Pretty much any 20A circuit that exists in a house (assuming no 20A circuits above and beyond code-required has been installed) is only allowed to have receptacles in certain locations.

For example, you may not add a receptacle to a 20A kitchen/dining room circuit that isn't in the kitchen or dining room.

You may not add a receptacle to a 20A laundry room circuit that isn't in the laundry room.

You may not add a receptacle to a 20A bathroom circuit that isn't in a bathroom.
Right, essentially my point. I thought I saw some posts about just attaching to another circuit to add 20A service…
 
Nothing wrong with having a bunch of 5-15 receptacles off of a 20A circuit. Who knows….

OP said he was using an extension cord to run whatever load he intended to use this new outlet for. Presumably that cord was plugged into a 15-amp circuit which could be used as a source for the new outlet.
 
OP said he was using an extension cord to run whatever load he intended to use this new outlet for. Presumably that cord was plugged into a 15-amp circuit which could be used as a source for the new outlet.
If a 15A circuit is used, then an extension cord ran from it, a 20A outlet sure doesn't seem necessary.
 
I thought I saw some posts about just attaching to another circuit to add 20A service…
There were and I asked what gauge wiring was ran to that outlet (no one knows, including the OP). Outlet circuits are typically 12-gauge even though 15A outlets are installed and if that's the case, a 20A outlet could branch off of it.

Another question is, why a 20A circuit? The last device I saw that actually needed a 5-20 socket was a UPS.
Air compressor, for example. I had a small 8-gallon that would barely start off a 15A circuit and when it did, it frequently tripped the breaker. Ended up running a dedicated circuit to the garage and put a 20A outlet in. Works great now.
 
Outlet circuits are typically 12-gauge even though 15A outlets are installed

That's not typical. It's possible that some electrician in your area had a practice of wiring 15-amp circuits with 12-gauge, but most do not.

Air compressor, for example. I had a small 8-gallon that would barely start off a 15A circuit and when it did, it frequently tripped the breaker. Ended up running a dedicated circuit to the garage and put a 20A outlet in. Works great now.

Probably should have had a 5-20 plug on it. Was it actually a UL-listed product? Another issue may have been that your 15-amp circuit had a lot of voltage drop on it. Contrary to popular belief, the electrical code does not mandate any maximum voltage drop. It just recommends no higher than 3%, as I recall.
 
That's not typical. It's possible that some electrician in your area had a practice of wiring 15-amp circuits with 12-gauge, but most do not.



Probably should have had a 5-20 plug on it. Was it actually a UL-listed product? Another issue may have been that your 15-amp circuit had a lot of voltage drop on it. Contrary to popular belief, the electrical code does not mandate any maximum voltage drop. It just recommends no higher than 3%, as I recall.
To be fair, we used 15 amp plugs on 12-2 wire all the time at my last job. Even new construction kitchen circuits for example.

I can’t remember who it was. Mike Holt (or someone similar?) in a video said the internals of a 15 amp plug were the same as a 20 amp plug. It was the plug style that was different. I will say the break away tabs on a residential plug do look pretty weak compared to #12 wire.

*I will say you are asking less of the recep if you tail it out and use 1 screw for the hot and 1 screw for the neutral vs using all 4 screws in a multiple plug circuit. The plug can take the 15 amps and the wire is good for 20.
 
To be fair, we used 15 amp plugs on 12-2 wire all the time at my last job. Even new construction kitchen circuits for example.

I think he was talking about 15 amp plugs on 12-2 wire with a 15 amp breaker (or that 15 amp plugs on 12-2 wire is a common practice--it's only common where a 20 amp circuit is required by code, and 15 amp plugs are used for cost savings. The majority of household circuits are not required by code to be 20 amp circuits, so the customer almost never wants to pay the extra cost to make them 20 amp circuits...).

Kitchen circuits are often 15 amp plugs, always 12-2 wire, always a 20 amp breaker. (The last two are required by code for kitchen/dining room circuits).

Unless you are compensating for voltage drop on a long circuit, there is not much reason to use 12-2 wire on a 15 amp breaker.
 
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I think he was talking about 15 amp plugs on 12-2 wire with a 15 amp breaker (or that 15 amp plugs on 12-2 wire is a common practice--only where a 20 amp circuit is required by code, and 15 amp plugs are used for cost savings).

Kitchen circuits are often 15 amp plugs, always 12-2 wire, always a 20 amp breaker. (The last two are required by code for kitchen/dining room circuits).

Unless you are compensating for voltage drop on a long circuit, there is not much reason to use 12-2 wire on a 15 amp breaker.
Gotcha. I missed the 15 amp breaker part.
 
If a 15A circuit is used, then an extension cord ran from it, a 20A outlet sure doesn't seem necessary.
It depends upon the number (even if anticipated) of users/loads coming off of it.

That's not typical. It's possible that some electrician in your area had a practice of wiring 15-amp circuits with 12-gauge, but most do not.



Probably should have had a 5-20 plug on it. Was it actually a UL-listed product? Another issue may have been that your 15-amp circuit had a lot of voltage drop on it. Contrary to popular belief, the electrical code does not mandate any maximum voltage drop. It just recommends no higher than 3%, as I recall.
Not typical? It’s what my electrician did when they installed circuits off of the new panel they installed. I’d suspect in spec house construction where everything is done as cheaply as possible, maybe that’s the case. But I’ve seen it before. Maybe it was due to the length and the voltage drop though…

I’ve also seen discussion on doing dedicated lighting runs/switch loops on 14ga even though the main run is done on 12ga and even perhaps protected by a 20A circuit.

There were and I asked what gauge wiring was ran to that outlet (no one knows, including the OP). Outlet circuits are typically 12-gauge even though 15A outlets are installed and if that's the case, a 20A outlet could branch off of it.


Air compressor, for example. I had a small 8-gallon that would barely start off a 15A circuit and when it did, it frequently tripped the breaker. Ended up running a dedicated circuit to the garage and put a 20A outlet in. Works great now.

Agree I’ve seen 12ga outlet circuits. Not always, not necessarily NEC/best practice I guess, except in places with the potential for high draw like bathrooms and kitchens.
 
I’ve also seen discussion on doing dedicated lighting runs/switch loops on 14ga even though the main run is done on 12ga and even perhaps protected by a 20A circuit.

Can't use 14AWG on a circuit protected by a 20A breaker. The only place I've ever seen that done was in a house built in the mid 70s, for the range hood and garbage disposal fed from the kitchen 20 amp circuits, and it wasn't right back then either.

Mixing 14AWG and 12AWG on a 15A circuit is also questionable, although not banned by code. The concern is that someone may see 12AWG leaving the panel, connected to a 15A breaker, assume that the whole circuit is wired in 12AWG, and change the breaker to a 20A.
 
Not typical? It’s what my electrician did when they installed circuits off of the new panel they installed. I’d suspect in spec house construction where everything is done as cheaply as possible, maybe that’s the case. But I’ve seen it before. Maybe it was due to the length and the voltage drop though…

The builder who built my house seems to have found it preferable to add more 15-amp circuits rather than fewer 20-amp circuits. Less of the outlets go dead if a breaker trips, and 14AWG wire is much, much easier to work with than 12AWG wire. Part of this includes not putting lighting and receptacles in the same room on the same breaker, so that if something plugged into a receptacle trips the breaker, the whole room isn't plunged into darkness.

As far as working with 12AWG, I wanted to strangle the electrician who thought it was a swell idea to join 4 12AWG romex cables in a kitchen outlet box where a GFCI was installed. That's just STUPID design right there. I could've done it better using LESS cable because the non-GFCI outlet (but fed from a GFCI) in the chain is right above the load center.
 
I mean somehow it got your attention enough to post something. What am I missing?
I was just making a comment about how something so simple , and relatively easy to accomplish became a seven page discussion . It got my attention early on in fact .
 
Can't use 14AWG on a circuit protected by a 20A breaker. The only place I've ever seen that done was in a house built in the mid 70s, for the range hood and garbage disposal fed from the kitchen 20 amp circuits, and it wasn't right back then either.

Mixing 14AWG and 12AWG on a 15A circuit is also questionable, although not banned by code. The concern is that someone may see 12AWG leaving the panel, connected to a 15A breaker, assume that the whole circuit is wired in 12AWG, and change the breaker to a 20A.
Agree 100%. So what I’ve seen is 12ga to receptacles and then 14ga switch loops. And then in some cases the “yellow romex” 12ga gets “upgraded” to a 10A breaker. Not advocating for that at all.
 
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