Replies

1. 
   FastEddie1 | Jul 30, 2003 04:05pm | #1

   Use three conductor cable (like 12-2 w/G) so you have a proper ground.  You don't have to use 20A outlets, but the circuit will be limited by the lowest rated item.  Look at the box or label to see what the watts are, or calculate it based on volts and amps.

   Do it right, or do it twice.

1. 
   Earthscaper | Jul 30, 2003 04:12pm | #2

   Thanks. I meant 2 or 3 wire w/ground (12/2g and 12/3g).

   So if I have a 20 amp circuit with 12-2g (or3g) and one of the receptacles is 15 amps and the other is 20, does that mean I won't be able to pull more than 15 amps through the 20 amp receptacle?

   Karl

1. 
   BillHartmann | Jul 30, 2003 04:45pm | #3

   First of all all recptacle are rated at 20 amps for FEED THROUGH.

   However, I suggest that you don't feed through the recptacle, but rather join the wires and the use a pigtail to connect to the recptacles.

   That said, the code allows 15 amp recptacles on a 20 amp circuit as long as there is more than one. And the common duplex recptacle counts as more than 1.

   And look at it this way, have you ever seen a device with a 20 amp plug on it.

   And buy the spec grade devices for about $1.50-2.00 and get the 15 or 20 amp versions, whichever is cheaper. They have the same guts in them, just an extra slot in the faceplate for the 20 amp version.

   Don't get the 39 cent ones and don't use the back stab wiring.

   (But some of the spec grade have back pressure plate connections which are nice).

1. 
   Earthscaper | Jul 31, 2003 12:12am | #8

   Thank you, everyone!

2. 
   IMERC | Jul 30, 2003 11:53pm | #5

   There is a difference.

   12/2 W/G = Black, white and ground (green or bare)

   12/3 W/G = Black, red, white and ground.

1. 
   Earthscaper | Jul 31, 2003 12:10am | #6

   Thanks, I know the difference between 12/3 and 12/2. Just said or because would use different wire based on the application (namely, 3-way switching).

   Thanks, Karl

2. 
   marv | Jul 31, 2003 12:12am | #7

   I agree - DON'T USE THE BACK STAB HOLES!  I had a circuit in the basement that was protected at the main panel by GFI breaker.  I used back stab on about 6 outlets.  The GFI kept kicking off when I tried to fire up the circuit.  It took me forever to figure out what was the problem.

   One thing you have to watch out for is overloading the boxes.  With 12/2 coming into/going out of a regular box, it gets pretty tight when you add anything else.

   Marv

2. 
   DouglasABaker | Jul 30, 2003 10:03pm | #4

   Yes, there are 20A switches, and just like the outlets, there are good ones and bad ones.  Get the good ones!

   As for ceiling fans, I couldn't guess at the actual wattage rating, but I've never seen one that required more than a 15A circuit...

   d-

3. 
   MalibuJim | Jul 31, 2003 12:32am | #9

   I agree that you do not need to buy the actual 20-amp outlets, but I just want to reitterate what someone else said about pigtailing.  I consider it a MUST and it's good wiring practice. 

   Also, I'm partial to metal boxes with mudrings.  I tend to wire all my devices with 4-inch square boxes and the appropriate mud ring for the device.  This set up gives you plenty of room when pigtailing, especially with #12 wire.  I also need this room since I always leave my splices and pigtails a little long.  That's how my dad taought me and it's always served me well.

   As far as the metal boxes go, yes they're more expensive, but how many are you going to need for this one project?  Maybe 50?  That's about $80-$100 more in material. 

   Good Luck!

1. 
   billyg83440 | Jul 31, 2003 01:04am | #11

   I helped my dad rough in the wiring in his house addition.

   Later my brother helped do the sheetrock & finish wiring (1 was 400 miles away at the time). He cussed me for using sq. boxes and setting them flush with the studs.

   "But, I told dad to pick up a couple mud-rings before putting the sheetrock up."

   "What the ________ is a mud-ring?"

   Guess it just depends how you've been taught. Your way would certainly make future changes much easier.

1. 
   brownbagg | Jul 31, 2003 04:03am | #12

   12 gauge for plugs and 14 gauge for light. But it cheaper just to buy a big roll (1000 ft) of 12 gauge and do everything. It like 1300 watts on 14 and 1900 watts on 12 ( I think, i do not have my book in front of me) I ran three plugs on each circuit but it can hold nine, depending what you plug in.

   12/2 is two wires and a ground

   12/3 is three wires and a ground  but 12/3 is not legal in the kitcern counter circuits must be two seprate runs of 12/2

1. 
   edlee516 | Jul 31, 2003 04:28am | #13

   Um.......wrong about that 12/3 in kitchens thing...........nothing wrong with it.  Maybe some local inspector doesn't like it, but that ain't in the NEC.

   Karl -  The only problem I have w/your 12/2  everywhere plan is that..it's a pain to work with.  You need to drill larger holes for multiple cables, you need larger capacity boxes and larger wirenuts.

   Maybe for a homeowner doing his own work one time only it doesn't make much difference.  But when  you do it all the time you start wondering WTF you're bothering to run the smoke detectors or a couple of lighting circuits w/3 and 4-ways in 12-gauge when 14 is so much faster and easier.

   JMHO........................Ed

   Edited 7/30/2003 9:36:32 PM ET by Ed

2. 
   England | Aug 02, 2003 01:21pm | #18

   The 12/3 to kitchen duplex receptacles is acceptable. You break off the small tab between the terminal screws on the hot side of the receptacle. This gives you a 20amp circuit on both halves of the duplex. You must connect the 12/3 to a standard 20amp, 2 pole, common trip circuit breaker as you have 240volts between the hot conductors. This is required to prevent a homeowner from assuming that the receptacle is dead by checking only the top or bottom 'halves'.

   Regards,

   John 

2. 
   Earthscaper | Aug 01, 2003 12:40am | #14

   Thanks. As for using metal boxes and mud rings, do you mean put the box flush with stud face, then add mudring after sheetrock is up? That may be better for my application anyway, as I plan to use 5/8 walls, and all the zip nail plastic boxes I've found have set-forwards of just 1/2 inch. (I was told to just set forward half inch and then make up the extra 1/8th of an inch with the screws.) That is if there are 5/8" mudrings.

   Further, (I've never put up mud rings) do the mud rings offer a good attachment points for plates?

   Also, would you use metal boxes for all fixtures as well? And for wall sconces, what are the best boxes?

   Thanks, Karl

1. 
   DaveRicheson | Aug 01, 2003 01:48am | #15

   Karl, set the boxes flush with the face of the studs. The mud rings come from 1/4" to 5/8" heights and are installed before the drywall.

   Are you hanging the drywall yourself? Mud rings and metal boxes may make a difference to the dw hangers, if you are contracting that part. Most hangers route the cutouts for device boxes. Mud rings, with thier rounded profile, are hard to get good clean cuts around. Metal boxes are  a no, no for rotary cutout tools.

   Dave

1. 
   Earthscaper | Aug 01, 2003 11:40pm | #17

   I am going to install the drywall myself. I plan to use plaster veneer, and do it myself.

   Suggestions on cutting out openings for mudrings?

   Karl

1. 
   DaveRicheson | Aug 02, 2003 01:57pm | #19

   Just measure and cut the holes in the dw as you hang it. Use a regular drywall saw.  Mud rings work real well for plaster because they set at the finish plane of the wall. If you use 1/2" dw and a 5/8" mud ring the mud ring will be 1/8" proud of the board, allowing the finish coat of plaster to floated right to it.

   I have never finished a dw lath/plaster wall, but worked on a lot of older home with that type of system. In the older homes, 3/8" dw lath was used, followed by a 1/4 to 3/8" plaster finish. The results was a 5/8 to 3/4" thich finished wall that was real close to the older wood lath and plaster wall thickness.

   I don't know the modern equivalent for plaster wall. Whatever it is, you should make sure that it doesn't exceed the width of standard door jambs unless you are making them yourself, or having them custom made for your wall thickness.

   If you use metal boxes and mud rings with type n/m wiring you should also plan on bonding the metal box to the gound wire.

   Dave

4. 
   rasconc | Jul 31, 2003 12:54am | #10

   I believe most of the ceiling fans I have looked at were no more than 100 watts for the fan plus the number of bulb sockets x the max rating per socket, usually 60 each.  I do not believe any would exceed the capacity of a 14 awg switch leg.  How about it sparkys?

5. 
   archyII | Aug 01, 2003 04:32am | #16

   In Chicago the lighting circuits have to be 15 amps.  My house (1930 bungalow) had a new panel installed and was completely rewired.  All of the wire was 12 ga. and the breakers were all 20 amps.  I put on an addtion and the electrical inspector had me change all of the lighting circuits to 15 amp breakers (both the existing and new work).