Metal Halide dimmer?

[DeepSeaBeauti]

Found this while hunting down caps for my metal halide's. Seams like a great idea for both energy savings as well as a cool effect. Especially if your using High watt MH's. Has anyone done something like this?

Heres the link.......
http://ecmweb.com/mag/electric_hid_lamp_dimming/

[klink67]

It would most likely ruin your ballast over time. The best way to adjust the light from your fixture would be raising and lowering it or getting a higher kelvin bulb that is less intense.

[DeepSeaBeauti]

It would most likely ruin your ballast over time. The best way to adjust the light from your fixture would be raising and lowering it or getting a higher kelvin bulb that is less intense.

With the way the circuit is designd it would not be any added stress on the ballast. It would actulay last longer, even the bulb. The cap is cutting the Ac signal down, kind of like a resistor would but without the energy loss with heat.

[pblogic]

thrilling conversation.

[DeepSeaBeauti]

thrilling conversation.

Great, You have anything to add, or just trying to build up your post count?

[sirreal63]

That article got kicked around when it was new, notice it is from 2004. Their is little advantage for us other than a ramp up and down cycle to mimic natural sun patterns. The reduction in bulb life is another factor to think about.

[REEF-n-Chicago]

Does anyone think this may extend the life of the ballast?

I have used the ebay bulbs for years w/ good results so I would tend to be less concerned about the buld and more about the dimming ability and the ballast....

Oh , and , DeepSeaBeauti great topic! I find it is best to not even respond to the "haters"

:)

[DeepSeaBeauti]

Does anyone think this may extend the life of the ballast?

I have used the ebay bulbs for years w/ good results so I would tend to be less concerned about the buld and more about the dimming ability and the ballast....

Oh , and , DeepSeaBeauti great topic! I find it is best to not even respond to the "haters"

:)


From what i have been reading, and from the electrical engineers i have spoken with at work believe that it will not harm the ballast. If you look at the circuit design of a magnetic ballast system the cap is there to increase impedance. This acts to reduce the current to the bulb, and in turn dims the bulb. Unlike the dimmer in your house that uses resistance, the cap uses impedance and therefor does not waste energy. The system only uses what the cap allows. With less power demand, the ballast has less current flow, with less current flow to the bulb it last longer.
The other cool thing about the dimming is the warm up time. Since your just changing the impedance in the circuit, the bulb is still getting power. when the rush of increased current flows in the bulb gets brighter. like wise was it dims.
Keep in mind this idea is for magnetic type ballast. It is possible to modifie ellectronic ballast but it is not cost effective since these can be purchase with these capabilitys. Search google, or yahoo, there are a bunch of good articles on this. Most aplications are for office, or industrial spaces for energy savings. To be able to cut power without waiting for warm up times.