Hello,

I bought a box of Leviton GFCI receptacles (3pcs.). On each receptacle it says 'GFCI R' 'CLASS A' '125V 60 HZ' AND '20 AMP'. But on the box that these came in is printed 15 Amp. The slots in the receptacles are of the standard polarized type for three prong plugs. I have some other non GFCI 20 Amp receptacles that have slightly different slots, three prong polarized but the left slot is like a sideways 'T'. I was told that the sideways 'T' slot on a receptacle is a feature found on all 20 Amp receptacles. I don't know if this is true. I need 20 Amp GFCI receptacles and can take these back to 'The Depot' if they aren't. Can I use these on a 20 Amp circuit if they say 20 amp on them? I know it kinda sounds like a dumb question, but burning down the garage is even dumber.

In the garage I'm going to run 2 general lighting circuits 15a 120v each, 1 outdoor lighting circuit 15a 120v (2 halogen bulb @ 500watt each motion detector fixture and 1 halogen bulb @ 500watt switched fixture), 1 garage door opener circuit 15a 120v, 3 general use receptacle circuits 20a 120v each, and 1 15a 120v circuit dedicated for a freezer. All of the general use receptacle circuits will be protected by having the first outlet being a GFCI receptacle and running the rest of the circuit(s) off of the load terminals. I want to make sure that I'm using the right ones. The sticker on the box says $28.99 for 3 of 'em. I don't know if their is a big price difference between the 15a and the 20a.

While I've got your attention maybe you could also tell me if some equipment has plugs with a sideways 'T' on them. I'm just a DIY'er but I haven't seen anything that needs this type of (20 Amp) receptacle.

Thank You

 

The sideways T means that the device can accept a 20 amp cord and plug.

Since your receptacles do not have a sideways T socket on them , they cannot be used with a device that requires a 20 amp receptacle.

However, the devices you have can be used on a 15 amp or a 20 amp circuit. They will provide pass through protection "downstream protection" at 20 amps.

As you have noted, very few devices need a 20 amp receptacle.

 

20 amp rated receptacles are not required on a 20 amp circuit unless there is only one simplex receptacle on that circuit. (Room for only one cord & plug device. However, there is nothing wrong with beefing up your circuit with the 20 amp models. Racraft is right - no sideways "T", no 20 amp rating. I would take them back if they do not have the "T" prong.

There are many cord & plug connected devices that have a 20 amp plug. Mostly industrial tools but fairly common on 120v window air conditioners. Otherwise, few residential appliances or tools come equiped with a 20 amp plug.

Juice

 

The 20-amp models are not any beefier.

In my opinion, this would be an overreaction.

 

I'd probably bump that outdoor lighting circuit up to 20A/#12 if you say it will have at least 3 500W lamps installed. 1500W is right around the 80% maximum load of a 15A circuit.

 

The panel I'm using in the garage is a used Square D QO 100a main breaker box with 20 spaces. The panel is still in good shape and I also have seven 15a breakers, three 20a breakers, one 30a breaker, and one 40a breaker. Kinda like a value pack . I'm running 12/2 romex to all of my circuits as I have bought 500' of it (for the house and the garage). I don't have any plans to use the 30a or the 40a breakers, at least not yet, so for now I can get away with just 12/2. I suppose it would be just as easy to put the double 500w halogen light on its own 15a breaker and put the single 500w halogen light on another 15a breaker.

As for the GFCI receptacles, the box also noted that they are rated for 20a feed through but only rated for a 15a plug and cord device. For my situation, this should be perfectly fine. I have no tools that use the 20a plug and cord and all the 'downstream' receptacles are going to be nonGFCI 20a with the slotted T. I will have plenty of places to plug 'em in if I ever get something with the 20a plug.

I was originally under the impression that a 20a general use receptacle circuit with 12/2 romex needed to have all the receptacles individually rated for 20a. So I went ahead and bought three packs of 10 of the nonGFCI 20a (slotted T) recpetacles. What I think I've found is that the 20a recpetacles were not required.? But these receptacles do have a bit more tension on the prongs of a plug and I do like that better. And I suppose a little bit of overkill won't hurt.

Is there a general rule of thumb for how many duplex receptacles should be installed on one 20a 12/2 circuit? These will all be in my garage and most of the time I will be alone in there using them. But occasionally there may be 2 or even 3 people in there working (rare ). Also, does the number of duplex receps. on any given circuit change since all but the first one will be indivually rated for 20a?

Thanks again for all your replies.

got to use one of these receptacles for the electric start on the snowblower tomorrow

 

On a 20 amp circuit you may have any combination of 15 amp and 20 amp receptacles. If you only have a single receptacle(not a duplex) then it MUST be 20 amp, but with duplex receptacles you can use any combination of 15 amp and 20 amp devices.

What you have to concern yourself with on a circuit is the load. The number of receptacles doesn't mean much, it;s what people can plug into those receptacles. Some people will use a specific number, such as 10, when talking about receptacles for a 20 amp circuit, but in a residential application there is no NEC maximum.

If you think that you may need to use two rather large (current draw) tools in your garage at the same time, then consider running two circuits. You might want to alternate circuits for each receptacle, but the actual layout choice is yours. Don't forget that each receptacle in the garage must be GFCI protected.

 

Thanks racraft,

I will be installing 3 recep circuits all with gfci protection. Their will be 8-10 recepts on each circuit so it seems that I'm gonna be OK.

I'm using the largest 4 gang metal boxes I can find at 'the depot' and I'm using the 7.5 cu in covers that extend out from the box. The boxes and cover are all going to have 2 duplex receptacles in them. But 'ut oh', I couldn't find any covers that are for a gfci recep and a standard recep. I've modified one with the angle grinder to fit the gfci and it actually turned out pretty clean. They cover everything but the face of the recep, see any problems with that? Is their an easier way? Maybe I should put the gfcis in their own 2 gang box at the beginning of each circuit.

 

I'm a little confused, or perhaps your terminology is wrong. "4 gang metal boxes" means space for four duplex receptacles, yet you state, "2 duplex receptacles in them."

Anyway, the big box stores only stock the commonly used parts. If they don't stock it then they don't get much call for it. You can find most other items at electrical supply stores or on line. Making a custom cover is okay, as long as it fits properly. You will want to make sure there are no sharp edges.

Anyway, if I were you I would use two or three gang boxes, with 2 or three duplex receptacles per box. I would alternate so that I had 2 different circuits per box (if using 2 gang boxes) or 3 different circuits per box (if using 3 gang boxes). I would place the GFCI receptacles in the same box or at least close together so that you would not have to search for the right GFCI to reset in the event of a trip. I would also label the circuits (especially if using 2 gang boxes) so I knew which receptacle was on which circuit, so I could avoid overloading a circuit.

 

Ahhh... yes that was my terminology mistake, apoligies. I will be using 2 gang metal boxes ( for 2 duplex receptacles).

I understand and appreciate your advice on using more than one circuit per box. Good idea and I probably wouldn't have done that. This way I can put 2 GFCI receptacles in one box for the beginning of two of the circuits. I was able to find a cover for the 2 gang box made for 2 GFCIs. So I wont have to make up any more covers (not a big fan of grinding and filing the metal covers as they are actually pretty tough).

Thanks.

-Things are always easier when you learn from someone who has already learned the hard way.