Building a house - Electrical Question?

Question

I'm watching my home being built by a nationally-known home builder. I have a few questions in regards to the wiring of the home.

The electricians ran a 12/3 to the dining room. The red is powered via a 15amp breaker and is powering two receptacles. The black is powered by a 20amp breaker (opposite phase) and powers the alarm system, master closet light, light and outlet in the attic, 4 recessed lights in the family room, the fan/light combo, 5 family room outlets with a sixth added late to the center of where all of the entertainment center wiring is located. A common neutral.

Q1 - Shouldn't both circuits be protected by the same size breaker?

Q2 - Shouldn't both circuits be balanced in load, or have similar loads?

Q3 - Shouldn't the family room have a 2nd circuit separating out the general purpose outlets from the definite purpose outlets, i.e. alarm system, attic outlet, and entertainment center.

Any help would be appreciated along with NEC article and paragraph. tx

Answer 1

Q1 =  No .  A 12 gauge current carrying conductor can be attached to any breaker size 20 amps or less....

Q2 =  Not critical but ideal.   Its a good idea to try to balace loads on both "A" and "B" legs of the panel but that cant be done until you move in and plug -in so to speak. It is imperative due to the common nuetral that those red and black conductors of that 12/3 stay on opposite legs however....

Q3 = I would run a separate dedicated line for the alarm. And one for the entertainment center but everthing else is fair game..  If you can catch the elecrician there and you have

room in the panel, offer him some cash to run some extra stuff before they close up the walls w/ sheetrock-drywall!!

Answer 2

You might have found an error.

*  The code requires "2 or more" 20A. appliance circuits

for the kitchen and dining room. (210-11, 52).

(Some inspectors like to see a separate circuit

for the D.R.)

No other outlets may be served.

  That red & black may have been switched.

If #12 wire is in use, the use of 15A. breakers might

well be questioned.

(#12 is rated for 20A.- [210.b2 permits

15A devices on 20A circuits.])

Answer 3

WTF? ask a carpenter

Answer 4

you need  two 20 breakers for the kitchen area...

  as for the alarm  i would that on a separate  breaker .

it wont take much to run it but it best on it own ....

i   wont run more than 5 outlets with a 20 amp breaker

  and the fan should run on it own  breaker . for   a good reason ,, say you get a power over load on the outlet  .  at least you will have light to work with . ie the fan . and every motor should have it own  , breaker

Answer 5

What is your problem? It is to late you ,have contracts which specify all this.If you know so much why did you not do the wiring.  You have contracts stay with them unless you want to go to court

Answer 6

I think you should always calculate on future loads and balance your loads out. Here we run light circuits on a 15 Amp breaker and plugs on a 20 Amp breaker. Then you group the plugs together depending on future expected load and the lights to be balanced and according to spec on the 15A breaker.

I would use a seperate breaker for lights and plugs for each room and an earth leakage for inside and one for outside if I had to wire my own house.

Answer 7

Q1 - No: Some appliances, like a dryer, require a 20 amp circuit and and 15 amp one would be dangerous and cause many problems, like shorts.  Other appliances only need 15 amps and running 20 amps would run up your electrical bill.  

Q2- Yes and No: The circuits should have close to the same load, but some loads/outlets in different areas of your house are used more often then others.  It also depends on placement of the loads and using as little wire (much cheaper), but still hit all the loads.  

Q3 - Probably not:  It is weird, though, that your electrician is doing this.  In Georgia's Electrical Code, electricians are not allowed to wire more then 10 loads to a 20 amp line.  You might want to ask him about that.  But if nothing happens, I would not worry.  Everything wired for AC power in wired in parallel to help prevent problems, like blackouts, shorts and grounding faults.  The main electrical consumer on that system is probably the entertainment center.  Alarm system don't take much power and most outlet appliances require alot less electricity then people think.  You are probably worried about over working your circuit.  If this happens, your breaker will pop and you will just have to reset it.  If I were you I would just ask him to run another line, although it will probably cost more.

If you have any questions, email me at [e-mail].

Answer 8

ur correct.....ask the builder to explain why this was done....then if u dont get the answer u like ask ur local building inspector......its ur money and ur house.....question them about it....

lic. gen. contractor