How do I determine the maximum number of lighting fixtures I can wire from one light switch? I'm thinking of 12 recessed light fixtures (on a dimmer switch for the main room of the basement). But is 14 AWG sufficient? or should I use 12 AWG from the switch to each?
-Paul
Are you installing a dedicated circuit for this lighting? What will be the total wattage of the fixtures you plan to use ? Will they be incandescent, line voltage, low voltage, , or fluorescent?
The wire size is dependent on the current the line will carry and the rating of the breaker/fuse. It is also important that you use a dimmer that is designed to handle the maximum current as well. In both cases I recommend going higher on the wire rather than lower if in doubt. Go lower rather than higher on the breaker/fuse. You may put 25 watt lamps in there, but some fool may decide to use 200 watt lamps.
All valid concerns. I planned on running 12AWG to the switch and then
14AWG thereafter to each of the lights. The recessed fixture maximum wattage is 75W. I will check on the rating of the dimmer switch.
I remember reading that it is against code to mix wire sizes in a branch circuit. I don't know if it is against NEC or a local building code somewhere, but I have the impression that most local codes follow NEC.
- Don Klipstein ( snipped-for-privacy@misty.com)
That's not right. The gauge of the wire is determined by the breaker size (or more accurately, the wire should be 12 gauge on a 20A circuit, or 14 on a 15A). So, if you go with a 20A breaker, you need
12 gauge all the way, but if you go with a 15A breaker, you are wasting your money to run 12 gauge to the switch.JK
All valid concerns. I planned on running 12AWG to the switch and then
14AWG thereafter to each of the lights. The recessed fixture maximum wattage is 75W. I will check on the rating of the dimmer switch.You cannot run 12 then reduce it to 14, however a 15 amp circuit is sufficient for the dozen lights at 75 watts each. You will need to split the lights on two standard 600 watt dimmers or use a 1000 watt dimmer if you want them all on one switch
You have to go to the breaker that feeds the light switch. Then see if it feeds any other circuits. The breaker will be rated for probably either 15 or 20 amps. This will determin if you need # 12 (20 amps) or # 14 (15 amps). The dimmer will also be rated for a certain ammount of current. YOu can take this current ( or the breaker current , whichever is less) and multiply it by 120 to determin the number of watts you can have in the circuit.
its just lights. I cant see you needing more than 14. Anyway, if 14 is not enough youll just get lower voltage, which will work to extend the life of the bulbs anyway...
CL
On 5/26/2008 8:39 PM dnoyeB spake thus:
BZZZZZZZZT! Wrong answer.
The correct answer is "if 14 is not enough [meaning not big enough for current being drawn through it] then you'll either 1) trip the breaker or 2) start a fire".
I forgot that point about not mixing wire types in a branch circuit. I'll stick with 12AWG throughout and think this through much more carefully. THANKS!
e the maximum number of lighting fixtures I can wire
12 gauge is always right for banch circuits like these, has less volatge drop too.i would put this on a new dedicated breaker, to minimize overloading a old circuit
14 guage "may" be sufficient depending on length of runs and stuff, BUT watch out, a lot of dimmers are only rated for a 600 watt load, if you have 12 fixtures with 75 watt bulbs, thats 900 watts, if you put 100 watt bulbs, thats 1200 watts, twice what the dimmer is rated for.
If I were you I would put this on a dedicated 15 amp circuit, run 14 guage to the switch box and break the lights out into two or three strings, each string with a 14 guage from the switch box and on its own dimmer switch.
If your going to use 75 watt bulbs, I think its OK to put 6 on a switch (450 watts), if your running 100 watt bulbs, I'd break it down to 4 on a switch (400 watts). I would not run any dimmer rated for 600 watts past about 480 watts (80% capacity).
You can find higher wattage dimmers, but they get very expensive very fast, plus with two or three controls you don't have to turn them all on at once.
compact fluroscents or imliar can save power. but frequently arent dimmable.
I have similiar issues here, the small CFs cant be dimmed
David Nebenzahl wrote in news:483bb2b9$0$11196$ snipped-for-privacy@news.adtechcomputers.com:
Ding! Ding! Ding! Ding! Ding! And you going to the the bonus round David!
That is completely incorrect. Not one ounce of truth in that statement...
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