15 vs 20 amp circuits

I'm renovating my basement and have a pretty fundamental question about the romex cable I'll be running throughout the space for lights and wall jacks. I'm having my old Federal Pacific breaker panel (150 amps) replaced with a new Cutler Hammer 200 amp box. Have hired an electrician to do that work for me. But I wondered why I'd bother with 15 amp circuits (14-2 romex). Is there a reason not to simply make all three of the circuits I'll be creating for the new basement 20 amp circuits, using 12-2 romex? Or is there a fire/shock hazard caused by using the higher amperage circuit breakers on those standard circuits.

Also, does on GFI protect the entire circuit on which it is located or do I need to install more? My basement, like so many, sometimes gets wet when the outside drains are blocked.

Reply to
mdb
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Wire costs a bit more, and its a bit harder to work with, but there is no downside other than that. I haven't used #14 in years. It has the added benefit of reducing voltage drop a little.

Properly installed, GFCIs protect the entire circuit.

Reply to
Toller

Cutlet Hammer isn't my favorite brand, but it's certainly better than FP. As for 15 Amp circuits, while it theoretically saves you a couple dollars worth of copper, I wouldn't consider it worthwhile. 15 and 20 A circuit breakers cost the same as do all the other devices you'll be using so only the wire would be different.

A GFCI circuit breaker will provide protection for everything connected to it. A GFCI receptacle will provide protection for everything connected downstream of it as well as what's plugged into it. A GFCI circuit breaker costs about 5X the price of a GFCI receptacle while providing the same protection. Generally it's best to simply insure that the first device on a given circuit is a GFCI receptacle.

Reply to
Pete C.

I use 15A for lighting circuits, and the occasional dedicated circuit where 15 is enough -- the wire is much easier to work with. I use 20A for all branch circuits.

One GFCI can protect the whole circuit, or part of the circuit, or just itself. Depends how and where you wire it.

Bob

Reply to
zxcvbob

Hi, If you need for 20 Amp circuits for higher demand devices or whatever. There is nothng wrong overdoing anything but economics. Copper price is very high lately. Anything load on GFI breaker or outlet is all protected.

Reply to
Tony Hwang

No extra hazard. Your electrician will prefer to work with #14 because it is easier (and therefore quicker) to deal with. Particularly if you might be running power tools, heaters or AC on those outlets, insist on #12.

Yes.

Vaughn

Reply to
Vaughn Simon

I concur with the others. I would, and have, used

12-2 Romex 20A circuits on my circuits. (Well, possibly with the exception of the lighting circuits which will most likely be low current.)

Yes, the circuit breaker types do protect the entire circuit. As do the receptacle types if wired that way.

All the better to use GFIs.

Several recomendations:

  1. Install larger boxes than the minimum standard code recommends. They are roomier and easier to work with.
  2. Install double or triple the number of outlets per wall than the minimum standard code recommends. You can thank me in the future.
  3. Use the .50 or .00 receptacles instead of the cheap $.49 types. They are much better built and sturdier.
  4. Don't use the simple push in terminals on the receptacles, use the old fashion screw terminals. The contact resistance is lower, I have measured this. OK, they do pass the UL code, but lower resistance has to be better.

Have fun!

Duane

Reply to
Duane C. Johnson

Second this, *do not* use the "push wire" type connections, they are the ones with the little release slots next to the holes. Do not however confuse "push wire" with "back wire" as they are not the same thing. With the better spec grade devices you will find many offer the "back wire" option which is a screw clamp type connection that works well and saves you the fuss of wrapping the wire around the screw. I've become a fan of these back wire clamp connections, particularly when using stranded wire pulled through conduit, where the back clamp eliminates the hassles of stray strands popping out from under the screw when you try to do a wrap around connection.

Reply to
Pete C.

I agree with all the posts so far regarding this and here are my own reasons for using all 20A stuff: Less wiring voltage drop (already mentioned) and receptacles are usually built better and have thicker copper in them so they hold a plug tighter. Other than that I personally don't find #12 that much harder to work with but then again I have run 4/0 aluminum wire for a main service entrance before.

The only rule I am aware of is that a single outlet 20amp circuit must have a 20 amp receptacle (multiple 15 amp receptacles are OK on a 20 amp circuit) but since I use 20 amp receptacles anyway for the better plug retention this is a moot point.

Reply to
Daniel Who Wants to Know

"Daniel Who Wants to Know" wrote in message

Most amateurs try to bend the end of the wire around the screw to form a loop, thus making it difficult. I did the same until I watched an electrician strip the sheathing off about a foot of wire, then stripped the individual wire about 9" from the end and he used the 9" to easily wrap the wire around the screw, then cut off the excess. It was speed and ease over the cost of a foot of wasted wire.

Reply to
Edwin Pawlowski

I've never found any problem with just stripping the normal 3/4" off and using the pliers tip of the combo pliers/stripper/crimper/screw cutters to put the loop in it for hooking over the screw. It takes about a second since you already have the tool in your hand from stripping the wire. That said, as I noted in another post, I've become quite fond of the "back wire" clamp type connections found on many spec grade devices, not to be confused with the terrible "push wire" connections which should never have been approved.

Reply to
Pete C.

Just about all the electricians I know and work with use the hole in the side of stripper that is made for making the loop that fits on the terminal screw. Insert tip of stripped copper - fold it over the side of the cutter - install on screw. The tips of the strippers can be used to close the loop tight.

Reply to
DanG

I guess it's my job to disagree with most of the other posters. 15A circuits let you work with 14 gauge wire. It is orders of magnitude easier to wire outlets and lights with 14 rather than 12. I use 12 only for workshops and kitchens where they might actually be needed. Most radios, TV's , and computers use less power today than even a decade ago. When was the last time you tripped a 15 A circuit breaker by overloading it?

mike

Reply to
Mike Payne

That makes 2 of us. A friend tried to talk me into using #12 for everything (as he'd done at his own place). When I told him that the bulk of the long runs were one light per circuit, and that nearly all of them would be 12W CFs, he started the "what about the next guy" angle. Sheesh! If there's a next guy, and if he wants to use 150W bulbs, and if he thinks that'll stress the #14, then too bad. :-)

Wayne

Reply to
wmbjkREMOVE

I have to disagree, I find the "workability" difference between 12 ga and 14 ga virtually unnoticeable. 2 ga copper is a bit of a pain to deal with, but much of anything below that is all the same to me.

Reply to
Pete C.

I read the dozen or so replies and two things come to light. If you are using #12 the push in terminals are not an option anyway. They are only listed for #14. #12 won't even fit unless you really force/drill it into the hole.

The second issue is 15a vs 20a O/C protection. There are people who say you are giving up 33% of your safety when you put an 18ga lamp cord on a 20a circuit. It is still legal but bear in mind you are protecting 7a wire with a 20a breaker.

Reply to
gfretwell

How is this substantially different from putting that 7A wire on a 15A circuit? The circuit breaker is there to protect the wiring in the house (i.e. the 12 or 14 ga wire), not to protect the appliance wire. Appliances typically have their own fuses, basic lamps being one exception. If that 18ga lamp cord gets damaged and shorts, the short circuit current is not limited to the 7A rating of the 18ga cord, and will be well over 20A, tripping the circuit breaker regardless of whether it is a 15A or 20A breaker. If it's in a bedroom, the new AFCI breakers will trip if the cord is damaged and arcing, but not a full short.

Reply to
Pete C.

I agree it is not a serious concern but it is the one argument I have heard about using 20a circuits for general lighting circuits.

Reply to
gfretwell

OK, now I am confused. I recently did a basement (15 amp for the lighting circuits, and 20 amp for the power outlets). I fought for a while with the receptacles that need the 'hook' on the end of the wire to go around the screw. With the 12 gauge wire I was spending an inordinate amount of time swearing at the wire not doing as needed. So I instead used the wee hole on the back of the receptacle - I stripped the end of the wire, pushed it in the hole and then screwed it down with a screw from the side. Is that what you are calling the "back wire"?

Cheers, Liam

Reply to
Liam Greenwood

As others have said, there is no real reason to opt for 15A over 20A other than a minor saving in wire cost and the difficulty of working with the heavier wire. But since you are having an electrician do the job it doesn't seem as though either one of those will matter at all to you. But I can vouch for the difficulty factor if you are doing the work yourself.

I recently added circuits and changed existing ones while doing a basement remodel and 12-2 wire is incredibly stiffer than 14-2 and pulling it through tight spaces above an existing finished ceiling really slowed me down. Even worse was pulling three 10-3 from the box at one side of the house to my workshop near the other end. That stuff felt like steel bar after a few hours of wrestling with it and if I hadn't been building a convenient soffit to cover ductwork for a goodly part of the run I might still be slaving away at it.

Oh, and if you do go with the 20A circuits, make sure that the electrician doesn't cut corners by using lesser-rated receptacles and GFCIs.

Reply to
John McGaw

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