15 vs 20 amp circuits

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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.
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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.
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mdb wrote:

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.
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mdb wrote:

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
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mdb wrote:

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.
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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
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Hi mdb;
> 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?
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.)
> 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?
Yes, the circuit breaker types do protect the entire circuit. As do the receptacle types if wired that way.
> My basement, like so many, sometimes gets wet when > the outside drains are blocked.
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 $1.50 or $2.00 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
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"Duane C. Johnson" wrote:

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.
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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
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Liam Greenwood wrote:

If it the wire from the back was clamped when you screwed it down, that is the good "back wire" type connection. Less prep time and good solid connections, particularly good for stranded wire. Nothing wrong with these connections at all.
The "push wire" type have a hole with a flimsy little spring tab that grabs the wire and a little slot next to the hole where you insert a small screwdriver to release the tab if you want to remove the wire. These are the horrendous ones with tiny contact area, low contact pressure and frequent intermittent connections.
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I just got back from Home Depot with 100ft 10/3, a sub breaker panel w/ breakers installed, 240/30a wall outlet. $255. Copper has indeed gotten expensive. I cant imagine the bill if I also had to tack on labor from a professional.
Duane C. Johnson wrote:

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A pro would have worked faster than you, but he'd be charging $75 an hour or so.
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And someone else would be accountable for any errors made during installation. That's a biggee these days; at least in the Litigious States of America.....
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Is it possible to make errors in home wiring?
Jim wrote:

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Yes it is. When I moved in this apartment I found an outlet that had a jumper wire from the neutral terminal to the ground terminal to make it look like it was grounded to one of those little testers with the three lights. The problem was that the circuit was also reverse polarity so the ground slot was "hot".
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Wow. Talk about making a bad situation worse...
A place I used to live in had a once-unfinished basement turned into a somewhat-finished one, obviously by one of the previous owners. About half of the outlets had hot and neutral reversed, so the people who did the work apparently didn't know what the silver and brass screws on the outlets were trying to tell them. But at least they got the grounds right.
    Dave
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Must have been an NCR trained maintenance guy.


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writes:

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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.
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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.
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