# Anyone heard of a electronic dimmable ballast?



## Missy B (Jul 8, 2007)

I'm completely re-doing my lighting system, because it was crap, and have decided on getting the iwasaki 250 mh watt bulb with lumenarc mini reflector and for the ballast I ran in to an electric dimmable one that I can dial up and down to increase/decrease the energy output. I guess my question is, has anybody ever heard of this, and what are the advantages/disadvantages to a dimmable electronic ballast vs. a normal electronic ballast??? I have a 92gal corner tank. Thanks!! Here's the link to the ballast: http://www.reefexotics.com/coralvue_lighting.htm (It's the 250 Watt Electronic Dimmable Ballast)


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## Zapins (Jul 28, 2004)

Try pm freemann he has electronically controlled ballasts, maybe he can help you with your questions.


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## spypet (Jul 27, 2007)

I know there are dimmable compact fluorescent spiral bulbs
where the bulb ballast pairing will work with a standard rheostat,
I wonder if a standard tube bulb would work with a dimmable ballast,
or if the bulb needs to be special to get excited with lower current.


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## slickwillislim (Oct 11, 2005)

I have never seen dimmable MH before, but I never looked. Its my understanding from dimmable t5 that a controller is needed in addition to the ballast but I could be way off. 

I believe Freeman had dimmable t5's. I am pretty sure the ballast he used was only available in 220v at the time and it requires a controller. I could be wrong though.


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## Gilles (Oct 12, 2007)

Dimmable ballast is a common practice here in the Netherlands. You have them in T5 and in T8. It is a ballast with an additional input (ranging 0-10v) and that controls the dimming intensity. So yes you will need a seperate controller for that and the ballast itself is very pricy here in the Netherlands (approx. 80$ for 1 ballast). The price is well worth it. I watch a sunrise and sunset every day!


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## Missy B (Jul 8, 2007)

Thanks for the info. on the T5's. Ice cap makes dimmable ballasts for fluorescents. I was just wondering about the metal halides with the electronic dimmable ballasts? Also, one of my biggest questions was, if I dim the bulb up/down is it going to affect the spectrum?


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## JG06 (Nov 5, 2006)

There are no dimmable electronic high intensity discharge ballasts that I am aware of. HID lamps are generally used to light large areas so I do not think the ballast manufacturers have developed a dimmable electronic ballast for them at this time. I could be wrong, but I don't think you'll find one. 

If you can...be preferred to shell out for it. When you put "electronic dimmable" in front of ballast, you add many more dollars to its cost. 

Good luck in your search.


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## Missy B (Jul 8, 2007)

They do actually make the electronic dimmable ballasts, here is the link to it: http://www.reefexotics.com/coralvue_lighting.htm

My biggest question is, whether or not the dimmable ballast will affect the bulb spectrum?


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## Freemann (Mar 19, 2004)

I do use dimmable ballasts with usb controllers here but that is for T5 lamps, from a research I have done in the past there are is no reliable way to dim MH's and the one that this company sells seem to be controlled with a dial that means you will have to manually adjust the intensity of the lamp or find someway to interface with the electronics of the ballast, it seems to me that the best way to go if you want to dim the lights of your tank is to use T5 lamps instead of MH's.


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## Fortuna Wolf (Feb 3, 2007)

I believe dimmable ballasts simply remove some of the cycles in the AC current going to the bulb. 
Say, its at 10,000 hz, and it removes 1 of every 3 peaks so it lights up 2/3s of the time, it effectively dims the bulb to the eye, but you can only do this so much or else you have to keep the emitters warmed up, which will drastically reduce the bulb life, so there's a limit to how dim you can make it. 

Make sense? As to who makes ballasts, I don't know, but it should work with any flourescent bulb.


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## Gilles (Oct 12, 2007)

Fortuna Wolf said:


> .... but you can only do this so much or else you have to keep the emitters warmed up, which will drastically reduce the bulb life, so there's a limit to how dim you can make it.


From my supplier of ballasts (working at Philips Lightning, the dutch guys who make those TL's) he confirms this. Dimming a light to (say) 5% or less will reduce the lifetime of the lamp and will give those black "rings" at either side of the tube. However, i have lamps that still give 90% of their capacity after x time untill they break.

As with the spectrum, i don't know and to be honest i don't think it alters the spectrum, only the intensity. That said; when you have a graph and only emit 1% of light, off course only the highest peaks in the spectrum will be seen (i mean,that seems logical no?)


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