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.
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.
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
On Jan 27, 3:03 pm, email@example.com wrote:
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
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.
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.
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://
4 - Can a fluorescent light bulb be dimmed?
Only with a fluorescent dimmer, not on a standard incandescent
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
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.
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!
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.
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, firstname.lastname@example.org wrote:
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