# substitution for 500wt halogen



## okkampguy (Jul 25, 2012)

Have 4-500wt halogen on 4 poles around a play-slab. Can't keep them from burning out within less than a month or two. Ideas for similar or brighter lumen metal halides or ???


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## jrmcferren (Aug 27, 2012)

okkampguy said:


> Have 4-500wt halogen on 4 poles around a play-slab. Can't keep them from burning out within less than a month or two. Ideas for similar or brighter lumen metal halides or ???



The least expensive option would be to find 130 volt halogen bulbs. This reduces the temperature of the filament and increases life. Life more than doubles when operating a 130 volt bulb on 120 volts. The bulbs will be a bit dimmer and will be a bit less efficient due to being underdriven.


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## electromage (Sep 2, 2012)

Depending on your budget and DIY skills, you might have a few options. If you've got a few thousand dollars to spend, you could get some big Rigid Industries lights, and wire them to a 12V DC power supply.

You could also take apart the halogen floodlights and mount some Bridgelux arrays inside, with high power LED drivers, and A LOT of cooling.


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## Anders Hoveland (Sep 8, 2012)

If you know where to look, you can find find a 100 watt LED chip with heat sink and power supply, all for under 100 dollars.


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## mattheww50 (Sep 8, 2012)

If color rendition isn't an issue and you are not on a tight budget, I would replace the lamps/fixtures with outdoor High Pressure Sodium lamps. HPS lamps have very high efficiency (typically close to 100 lumens/watt) and very long life. IF you use these lights extensively, the lower electrical consumption and longer life of the lamps will go a long way toward covering the costs. While 70 watt HPS lamps would have less output than your current 500 watt halogens. 100 watt HPS lamps would have close to the output of your 500 watt halogens, however 100 watt outdoor fixtures are more difficult to find and more expensive than 70 watt fixtures. Years ago I replaced a pair of 300 watt Halogens lighting the front of my house with 70 watt HPS lamps. Big savings on electricity, huge increase in lamp life.

There are three downsides: The fixture/ballast is fairly expensive. The color rendition is poor, and it takes a couple of minutes for them to reach full output. 

The other choice is to use 175 watt Metal Halide lamps such as GE mutli-Vapor lamps. These are also close to 100 lumens per watt, you can get reasonably good color rendition (CR 75 typically).
The bad news is cost and these lamps take even longer than HPS to reach full output. The other potential issue is they must be placed high enough to insure that the cover glass cannot
be hit/broken from the ground. UV output from these lamps can be substantial, and the fixture enclosure provides UV protection.


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