Wiring question?

[david]

In my garage i noticed a 15 Amp receptacle connected to a run that had a 20 AMP breaker on the main electrical panel. Is this normal?

The wire used was 12-2. The receptacle is the last electrical device on the run. The 20AMP circuit also feed the garage door.

Thanks

[RayV]

Yes, it is 'normal' but not correct. Standard outlets are a lot cheaper than 20A outlets and that is probably why it was done. Change the outlet to a 20A outlet.

[Doug Miller]

Perfectly normal.

You're fine. No problems.

[krw]

Yes, this is normal. If there are more than one receptacle on the circuit you're fine.

You're good to go, though if the receptacle is in the garage, outside, or basement it should be on a circuit protected by a GFCI (the garage door shouldn't).

[Doug Miller]

Sorry, but you're wrong. Use of 15A receptacles on a 20A circuit is explicitly permitted under the National Electrical Code. [2005 NEC, Article 210.21(B)(3) and accompanying table]

Well, that, and the facts that (a) it's Code-compliant, and (b) 20A receptacles probably were not necessary on that circuit.

Nonsense. There's no reason to change it, because there's nothing wrong with it.

[Doug Miller]

Actually, to be precise, the *receptacle* should be a GFCI (or protected by one). There's no need, or requirement, for the entire circuit to have GFCI protection.

[david]

thanks for your reply now here is what i want to do.

I had mentioned that the 15 amp receptacle is the end of the line for

20 amp circuit in the garage. The wiring is 12 -2. The load on the 20 amp circuit is very min. Thus i would like to extend the wiring from the receptacle to install a light (120V with 2 120 Watt bulbs) which is controlled by a switch. Would the switch that i plan on installing need to be 20 amp or would 15 amp do. I don't mind paying extra for a 20 amp. Also i will be using 12-2 cable as it is 20 amp circuit.

Here is the circuit diagram

(have not shown ground wire)

---Power Existing Wiring--Black----[RECEPTACLE Top]-White

---New wiring---12-2---Black-- -[REC BOTTOM ]-White | | | | | |

Switch | |

|------LIGHT--------------------------|

Any tips/suggestions let me know

Thanks

Doug Miller wrote:

[krw]

Yes, that's what I meant to say. I made the point that the garage opener didn't need to be (shouldn't be) GFCI protected but can be on the same circuit.

[david]

Does an outside light with a switch on the inside be on a GFCI protected receptacle?

krw wrote:

[Doug Miller]

15A switch is fine.

[Doug Miller]

Doesn't have to be, but it's not a bad idea.

[david]

[RayV]

Sorry, I thought the OP was in Northbrook, Il or one of the many other locales that require a 20A receptacle on a 20A circuit.

Isn't a garage a likely place to have an appliance that draws more than

15amps but has a standard plug? Or is it safe to assume that the 15A outlet can handle more than 15 amps? My table saw has a standard 3 prong plug but draws more than 15 amps on start up, and possibly under heavy load. Other garage appliances like a bench grinder can also draw more than 15 amps for a longer period of time.

What is the reasoning for requiring a 20A receptacle on a 20A circuit if it is the only receptacle but allowing multiple 15A outlets on a single 20A circuit?

[Doug Miller]

While 20A outlets may be required by various local codes, this is not a general requirement.

Any appliance that draws more than 15A as a continuous load will not have a "standard" (i.e. 15A) plug -- it will have a 20A plug.

For a short time, sure. Continuous load, no way.

Must be a heck of a bench grinder... And I'll bet that if you look at the owner's manual for your table saw, it recommends a 20A circuit.

I think the idea there is that the single receptacle implies a dedicated circuit, and if the circuit supplying a dedicated load is 20A then the receptacle should be also.

[Goedjn]

There should be no UL-listed appliance that draws more than 15 amps that has a plug-configuration that will fit in a 15A outlet. That's the whole point of the 20A plug configuration.

[gfretwell]

It does happen. I have a U/L listed 1650w smoker with a 5-15 plug. It has popped breakers all over town

[Goedjn]

Thats why I said "should" instead of doesn't. I believe that the receptacles are designed to handle the current anyway.

Is it a replacement plug, a forged UL seal on a chinese-export device, or did the UL just screw up?

Have you got a manufacturer-id and product number?

--Goedjn

[Chris Lewis]

1650 / 120 = 13.75A.

In other words, your smoker _theoretically_ doesn't draw more than

15A, and hence 5-15 is okay.

It is somewhat on the high side tho, given that it's probably running for hours at a time, and is above the 80% rule.

[RayV]

Jet contractor table saw 708301K Manual is here:

Standard three prong plug and after sitting overnight in a *cold* garage will pop a 15A breaker almost without fail.

My 6" craftsman bench grinder, cold, will do the same thing until it warms up. I'm guessing since the motor on the grinder is smaller it takes a lot longer to get up to speed than the big motor on the TS.

[gfretwell]

Except for 210.23(A)(1) Cord-and-Plug-Connected Equipment. The rating of any one cord-and-plug-connected utilization equipment shall not exceed 80 percent of the branch-circuit ampere rating.

It is also certainly a continuous load since you smoke things all day