Bulbs in totally enclosed fixtures

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Old 09-05-17, 06:25 AM
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Bulbs in totally enclosed fixtures

How do you know if a bulb is rated for use in a sealed fixture? It's rare that I see any mention of this on packaging.

I have a 5-lamp hanging fixture over a dining table. The candelabra bulbs sit upright and the little "plates" under each one collects dead bugs. I think this is gross over a dining table so I want to reassemble the fixture with the bulbs hanging down & enclosed in mason jars so there's no place for bugs to collect.
 
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Old 09-05-17, 08:56 AM
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There is no such requirement. As long as there is space around the bulb, nothing touching the bulb you should be ok with the standard bulbs.
 
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Old 09-05-17, 11:07 AM
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There is no problem using the bulb burning "base in any direction" but turning your lamp sockets over and then enclosing the bulb will require your fixture to use high heat wiring to the sockets which more than likely is does not now.
 
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Old 09-05-17, 04:11 PM
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Call the bulb manufacturer and ask if their bulb can be used in your application. I bought some bulbs for use in an enclosed ceiling fixture....the bulb package info was vague and the info provide by the hardware store clerk was wrong. I called the manufacturer and they explained what type of fixture their bulb could be used in and why.
 
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Old 09-05-17, 05:20 PM
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Are they LED bulbs? If they are then look on the ballast. It will say if they are rated for an enclosed luminary. If you aren't using LED's then start. You won't need to worry about electrical problems. The only drawback with using an LED not rated for enclosed lumnarfies is the average life of the bulb will be diminished. They will tend to run hotter which is bad for the electronics. I would also suggest you stick with a known brand of LED such as GE, or Philips. SATCO bulbs are an American company, but all the bulbs are made in China. I would steer clear of those.
 
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Old 09-06-17, 06:00 AM
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I'm leaning towards using the LED vintage-looking bulbs. I think they'd look great in the blue-tint Mason jars.

Thanks for the tip on looking on the base of the bulb. I'll get out a magnifying glass & check there.

I would guess using LEDs would eliminate any concern about what grade of wire is used inside the fixture?
 
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Old 09-06-17, 04:44 PM
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I would guess using LEDs would eliminate any concern about what grade of wire is used inside the fixture?
Pretty much! The ballast will get hot but the glass stays cools to the touch. Generally speaking wattage = heat. So any LED bulb rated lower than the max allowed in the fixture should be OK.
 
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Old 09-06-17, 05:56 PM
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the power supplies of leds and cfls really don't like excess heat. The life of electronics goes down exponentially as you raise the temperature.

the air has to be able to flow through the area of the bulb.

Enclosures that are only open at the bottom will greatly shorten the life of the power supply. You won't get 15 to 25000 hours from an led if heat builds up.

The higher the wattage, the more likely this will be a problem.

If you use dim 2.5 watt leds, not a problem.

Use 5 to 10 watt leds and it will begin to be a problem.
 
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Old 09-06-17, 07:02 PM
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The life of electronics goes down exponentially as you raise the temperature.
But will still far outlast a normal or incandescent bulb and give you more lumens at a lower wattage rating ergo less cost of power. But that lower cost of power most likely will not offset the cost of the LED bulb. At least not yet at this time.
 
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Old 09-07-17, 07:14 AM
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Originally Posted by Muggle
the air has to be able to flow through the area of the bulb.
This can't literally be gospel or there wouldn't be any such thing as lamp globes and enclosed (or sealed) fixtures.

I have seen advice in these pages to make sure replacement bulbs for enclosed fixtures are rated for such enclosures so that's why I posted my question.
 
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Old 09-07-17, 12:28 PM
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Unless the lamp is rated for totally enclosed fixtures, figure a major reduction in lifespan.

Most of the light fixtures in use were designed and approved for incandescent lamps which don't have electronics impacted by heat.


CFLs have a rated reliable temperature operating range (usually -20c to 60c) which can be exceeded in enclosed fittings and some even say "Not for use in totally enclosed luminaries")

LED power supplies have some similar components like capacitors and can have similar restrictions.

You can probably find leds designed for high temps, at a much greater cost and not at big box retailers.

They will work, they may not last in heat trapping fixtures. Figure that 25 000 hour rated life can go down to 1000 hours.

Base up in a globe that doesn't allow warm air to rise out is pretty much the worst application what so ever and would require significant heatsinking around the bulb.

Below there's a pic of a recessed led specifically designed to be installed in cans with no ventilation. It has a large heatsink -> the candelabra lamps aren't able to dissipate heat in the same way, leading to premature failure.

 
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