# double-checking wiring for basement lighs

• posted on January 27, 2007, 8:03 pm

Done lots of reading and think this is okay - but thought I'd post to get others thoughts:
I'm finishing a room in the basement by putting in 18 recessed potlights (large room). They are halogen bulbs and the lights are rated for 50 watts each. This is okay on one circuit? (If I did my watts/amps-math right...) Also, can I use a standard dimmer switch for the halogen bulbs?
Thanks for the input.

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<%-name%>
• posted on January 27, 2007, 8:10 pm
That's 900 watts. You will find that dimmers that can handle that amount of power are large, bulky and expensive. It would be better to select half the lights for one circuit and the other half for another circuit. Sometimes you may not want all 18 lamps on at once. This way a standard 600 watt dimmer can handle the load of 9 bulbs easily, and will cost less. You will only need one circuit to feed your two dimmers.

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<%-name%>
• posted on January 27, 2007, 8:18 pm
I assume these are 120V halogen (i.e. not low voltage)? If so 18*50watts/120V=7.5 amps. This is should be okay on a dedicated circuit. What is the maximum rating on the potlights? I would check the calculation with the maximum wattage and verify that you still are under 15 amps. I suspect (but don't know) that the code inspector will be looking at the maximum not what you plan to use. BTW how big is the room?
On Jan 27, 3:03 pm, snipped-for-privacy@gmail.com wrote:

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<%-name%>
• posted on January 27, 2007, 9:19 pm
One 15 or 20 amp circuit is fine to feed the lights. You should use dimmers for magnetic low voltage transformers, assuming that's what you'll have. These dimmers are not rated as high as line voltage dimmers, a Lutron Skylark 600 watt MLV dimmer is only rated for 450 watts, and that is by itself in a single box. If you gang several together in multigang boxes, their wattage capacity is diminished further. You could go for something like a Lutron Nova MLV ,in a high wattage model, but I think they sell for somewhere around \$500

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• posted on January 27, 2007, 10:15 pm
Are these line-voltage PARs or low-voltage MR16s? If they are the latter, I would recommend the more energy-efficient IR MR16s that are available from Philips, GE and Osram Sylvania.
A 37-watt IR MR16 produces the same amount of light as a standard 50-watt and with eighteen fixtures you'll save a total of 234-watts (plus reduce the load on your air conditioning system). Again, the same amount of light, but for 25-per cent less power and, as an added bonus, longer service life.
Sylvania's 37-watt TRU-AIM IR MR16s have a rated life of 5,000 hours and come in 10, 25, 35 and 60 degree beam widths. For maximum light spread, select the 60 degree version.
I personally prefer the Sylvania product, but any of the other brands will do an equally good job. You'll have a hard time finding these lamps in the normal retail channels but any lighting/electrical wholesaler should carry them and you should be able to purchase them through their cash and carry counter.
Cheers, Paul

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<%-name%>
• posted on January 27, 2007, 9:32 pm
snipped-for-privacy@gmail.com wrote:

Hi, That's OK but I wouldn't put all 18 lamps in one circuit. If something happens all lamps will go out = dark. I'd split them into two groups feeding from separate branch. Also it is easier to get two typical 600W dimmer as well. High power dimmer close to 1000W handling is big and expensive. If I were you, I'd install energy saving fluorescent bulbs; sunlight and daylight ones mixed.

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<%-name%>
• posted on January 28, 2007, 2:31 pm
Question:
Will those 'twisty' fluorescent light bulbs work with a dimmer?
wrote:

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<%-name%>
• posted on January 28, 2007, 3:16 pm
3. Can I use a compact fluorescent light bulb with a dimmer switch?
To use a compact fluorescent bulb on a dimmer switch, you must buy a bulb that's specifically made to work with dimmers (check the package). GE makes a dimming compact fluorescent light bulb (called the GE Longlife Plus Soft White Energy Saving Bulb) that is specially designed for use with dimming switches. We don't recommend using regular compact fluorescent bulbs with dimming switches, since this can shorten bulb life. (Using a regular compact fluorescent bulb with a dimmer will also nullify the bulb's warranty.)
And here's a poorly worded section from an FAQ from http:// www.westinghouselightbulbs.com/faq_01.shtml#fluoro4
4 - Can a fluorescent light bulb be dimmed? Only with a fluorescent dimmer, not on a standard incandescent dimmer.
5 - Can a compact fluorescent light bulb be dimmed? Westinghouse has a few compact fluorescent light bulbs that have been specifically designed to be able to be dimmed on an incandescent dimmer. However, generally speaking, CFL light bulbs cannot be dimmed.
My comment on the wording of the FAQ: If you stopped reading after question 4, which deals with "a fluorescent light bulb" you'd think you had your answer and would never get to question 5, which deals specifically with CFL's. In fact Question 3 deals with CFL's so they seem to be jumping back and forth between CFL's and "regular" fluorescents, which could be quite confusing to the reader.

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<%-name%>
• posted on January 28, 2007, 3:38 pm
Thanks for all the advice - I'll put them on one circuit and on two dimmer switches (more flexibility in the one big room [40x20] ). Now I just need to figure out how to run that circuit so that one switch doesn't effect the other set of lights. (Before I scare anyone, I am relatively new at the electrical stuff - but I do get a cert. electrician to come in and check over everything and then attach my circuits into the panel...I'm still wary of the panel....). Can the power source just come into one dimmer (which goes out to its lights) and then onto the next dimmer for the next set of lights? I'll have to get out my sketch pad and try and figure it out...
Thanks for the quick & helpful responses!

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<%-name%>
• posted on January 28, 2007, 3:59 pm
You'll bring your feed into a double box, then pigtail the black out onto the two dimmers. Then go from the dimmers to the two runs of lights.
--
Steve Barker

< snipped-for-privacy@gmail.com> wrote in message

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<%-name%>
• posted on January 28, 2007, 4:59 pm

Some jurisdictions have a limit on the number of devices on a circuit. Check your local electrical code.

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• posted on January 28, 2007, 1:29 am
snipped-for-privacy@gmail.com wrote:

Ill add something that I don't thing has been noted. Halogen lamps rely or a process in the lamp to maintain their brightness and life. If you dim them more than about 30% it will actually reduce their life.
--
Joseph Meehan

Dia \'s Muire duit

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<%-name%>
• posted on January 28, 2007, 10:48 pm
Remember that 600 watts is the max, when you pop off one of the ears so it will fit in a dual box, you lower the capacity a lot . I had one pop last year after five years that was near capacity, the replacements lasted a few days - and I was under the max On 27 Jan 2007 12:03:13 -0800, snipped-for-privacy@gmail.com wrote: