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Can a high-pressure sodium bulb be replaced by metal halide?

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Sum Guy

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Jul 26, 2010, 10:02:19 PM7/26/10
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I've got an outdoor parking-lot fixture with high-pressure sodium bulb
that has burned out. The bulb is a 70-watt Sylvania Lumalux:

http://www.greenelectricalsupply.com/lu70-med.aspx

Can I replace this with something that puts out a more whiter light,
like maybe a metal halide bulb, or is the ballast in this fixture
specific and can only with with high-pressure sodium bulbs?

RBM

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Jul 26, 2010, 10:28:59 PM7/26/10
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"Sum Guy" <S...@Guy.com> wrote in message news:4C4E3E2B...@Guy.com...

The ballast is specific to the type of vapor and wattage


Art Todesco

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Jul 26, 2010, 11:18:03 PM7/26/10
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There are some specific MH lamps made to
work with HPS ballasts. But, there are
usually pretty expensive and are not as
efficient at a "real" MH lamp working
with a MH ballast. My old church was
built with 26 400 watt HPS fixtures. We
found 2 manufacturers (maybe even 3)
that made a MH lamp to work with that
ballast. It was a very pricey mistake
made by the archetect/engineer that the
church ultimately had to pay for.

Sum Guy

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Jul 27, 2010, 12:24:42 AM7/27/10
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RBM wrote:

> > Can I replace this with something that puts out a more whiter
> > light, like maybe a metal halide bulb, or is the ballast in
> > this fixture specific and can only with with high-pressure
> > sodium bulbs?
>
> The ballast is specific to the type of vapor and wattage

Does that mean that I can't (or shouldn't) replace the original 70 watt
HPS with, say, a 100 watt bulb (assuming it was the same size and would
fit in the fixture) ?

Evan

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Jul 27, 2010, 3:41:59 AM7/27/10
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It means that running a light fixture with a mismatched lamp/ballast
will do several things:

a. reduce lamp life
b. consume more energy for less lighting output
c. burn out the ballast
d. cause the lamp to catastrophically fail

If you want a brighter lamp in your fixture, you need to have a
qualified electrician retrofit your fixture with the proper ballast
which will support using that lamp in the fixture... If the new
desired lamp will even fit inside your fixture housing...

~~ Evan

Message has been deleted

Tony

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Jul 27, 2010, 12:35:59 PM7/27/10
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I took the transformer out of mine and rewired it to take regular bulbs.
I have a CFL in it that gives me all the light I need there. No
reason to light up the whole mountain. It still uses the dusk to dawn
circuit which has a relay so CFLs will work. Those original lamps do
put out some really ugly pink light.

blakeidd...@gmail.com

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Oct 13, 2016, 4:21:23 PM10/13/16
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Just to reiterate no you cannot but the compact fluorescent idea was great it's very easy and extremely cost-effective and you don't have to have a certified electrician to do it incredibly easy

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