I am in the process of fixing up half of our basement. One room is a wet bar, while the other is a home theater. It’s 95% complete. I ran 12 AWG Romex for the receptacle circuits. There are about 20 receptacles, and three or four receptacles per circuit.
I don’t plan on plugging a heavy load into any receptacle. But I like overkill, so each receptacle is rated for 20 A.
Today someone told me that 20 A receptacles are only allowed on dedicated circuits. In other words, I can’t have more than one 20 A receptacle on a circuit. Is this true? Crap, I hope not… :smack:
That doesn’t make sense how it’s being applied. The outlets are rated to handle 20 amps instead of 15 amps. Using a better rated outlet shouldn’t penalize you. You need to ask locally about the code. I’m betting it means if you are running an appliance that needs a 20 amp outlet, you can’t put another outlet on the same line. You can never account for weird local codes though.
I did install some dedicated receptacles (microwave, refrigerator, etc.). But I also have circuits with multiple receptacles. As mentioned, all receptacles are rated for 20 A.
As long as you’ve got 20A breakers, 12 GA or larger wire, and 20A receptacles, you’re good. Code allows up to thirteen 20A receptacles on a general-purpose residential circuit, so you’re well within that limit. Your local jurisdiction may have adopted a more restrictive rating - perhaps 10 instead of 13, but 3 or 4 should not be an issue.
What your friend might be thinking of is 30A circuits, which do need to be dedicated. I can’t even think of something you might have in a house that would be on such a circuit at 120 volts, other than maybe a window air conditioner. (As opposed to 30A 240V circuits for a clothes dryer or large stationary power tools like table saws.)
If you’re bored, the relevant section of the NEC is here. (PDF)
I like overbuilding too. I tend to use #12 wire when #14 will do, but I use 15 amp receptacles. Internally, the only difference between a 15 amp and a 20 amp receptacle is the horizontal slot (well, technically the 20 amp ones are tested to a higher standard for certification, but realistically there’s no difference). If you don’t plan on plugging high amperage equipment in there, why use the 20 amp outlets?
The theory is that if you use 20 amp receptacles they expect that you’ll be plugging high current devices in there, so they want it on a dedicated circuit. That said, I don’t think the NEC actually prohibits what you’ve done, but local codes might.
I can’t remember if its code or just common practice, but microwave ovens are typically put on their own dedicated 20A circuit. Your fridge may be required to be on a dedicated circuit as well in some areas, though that’s not an NEC requirement.
To add to the discussion, I believe it is general practice that all of the kitchen outlets will be 20 amp and will be on one or two circuits (sometimes alternating outlets between two circuits). The idea being that you regularly plug in high draw devices (like blenders) into the kitchen. So, it is perfectly reasonable to have multiple 20 amp outlets on one circuit.
Just to add, kitchen outlets are typically on 20A circuits with GFCI’s installed. We don’t have a lot of basements in Southern California but I think you may want to install GFCI’s in the basement in case it ever fills up with water.
Thanks for the info, gotpasswords. I feel a bit better now.
When I connect two Romex cables to one receptacle, the copper conductors internal to the receptacle (around the screws) must carry the current. I was thinking (perhaps wrongly) that a 20 A receptacle would be better in this respect, i.e. a 20 A receptacle would have lower resistance internal conductors. As mentioned, I tend to do things in overkill.
See that small, easily removable tab between the screws on each side of the outlet? That is what conducts electricity between the terminals on each side of a duplex outlet.
As was stated, the difference between a 20-amp outlet and a 15-amp outlet (most of which are actually rated for 15 or 20 amps) is the shape of the slot where the neutral side of a polarized plug goes. Some appliances that require 20 amps have the odd-shaped plug so that they can only be inserted into 20-amp outlets, which (if the wiring is done to code) ensures that the appliance is on a 20-amp circuit. The outlets themselves are identical internally.
I didn’t realize that. My house is a log cabin, which makes it difficult to run wire, so I used 20amp throughout because the minimal number of outlets would tend to get heavily loaded. All the outlets have that sideways T slot. I was pretty sure it was up to code because I have electricians check all my work. I assumed the 20amp outlets used more metal in the internal connections, but I realize now they would all have more metal than the wire connected to them anyway and wouldn’t overheat. I did cheat by adding an outlet onto the 40amp 240v line for the electric stove for my welder, but I wouldn’t use them at the same time. The electrician (a friend) said no inspector would raise a ruckus over that, and at worst just make me remove the outlet. He also said, ‘you added that after I checked everything’.
But thanks, to you, and to all the others who add these little details to these discussions.
The 'fridge is an odd one. Some places actually want it on the primary kitchen light circuit so that it will be more likely noticed if the breaker pops. Smoke detectors are almost universally put on a lighting circuit for this reason.