DIY metal halide question

[whaase]

I've bought some 250w, 10000k MH bulbs from Sunaquatics, I was going to buy these ballasts from Brite-Lite:

http://www.brite-lite.com/CdnShop/Publish/cat40.htm

But then I read this.

http://reefcentral.com/forums/showth...hreadid=256719

So my question is, will the ballasts from Brite-Lite work with these bulbs? And why would color temp make a difference to a ballast?


Walter

[Coffeeman]

I believe that bulbs 10k and over use a pulse starting ballast which is a different type of ballast.Not too sure though,I bought one of these ballasts once from albright lighting, it was 175 watt and I got it to fire a 14k bulb.I found that the ballast was very loud even in a ballast box,not to metion the heat.If I was you I would email Sun Aquatics,they were offering a 250 watt electronic ballast for only $119.00.

[beaker020]

The bulbs and ballasts mentioned in that RC thread and in the linked article are actually a modified Mercury Vapour bulbs (they are called metal halide conversion bulbs). These bulbs can run on hetal halide ballast but are often run on MV ballast because they are cheaper. MV ballasts, however, can only run MV bulbs. A metal halide ballast should fire any apropriate wattage MH bulb regardless of colour temp with the exception of double ended (HQI) bulbs and Radium branded bulbs. Double ended bulbs require a special ballast and Radiums require pulse start.

A word on those sun aquatics bulbs; If you have fans in your hood dont point them directly at the bulbs. On some bulbs, the color and intensity drops dramatically if there is a fan blowing on them.

[whaase]

Thanks for the answers! I'll keep that tip in mind about the fans.

Walter

[StirCrazy]

Originally Posted by beaker020

Double ended bulbs require a special ballast and Radiums require pulse start.

almost all 250 watt 10000K bulbs in the hobby should be run on a 250 watt HQI ballast. the readium especialy, as almost every bulb is built to german specs which are based on the HQI ballast.

Steve

[Delphinus]

Originally Posted by StirCrazy

almost all 250 watt 10000K bulbs in the hobby should be run on a 250 watt HQI ballast. the readium especialy, as almost every bulb is built to german specs which are based on the HQI ballast.

Just a appendix to what Steve says ... there is only one HQI ballast that I know of in the cap/coil style (i.e., non-electronic) ballast and it is made by Advance. (Advance catalog #71A5880 [ link to info ]).

The one thing to keep in mind when using this ballast, notice that the "BTL" number associated with the ignitor is 5 feet. "BTL" is "ballast to lamp" distance, this is the maximum length of wiring between ballast and lamp, including ballast to ignitor. 5 feet can get used up pretty quickly (i.e., may not even be adequate if you want your ballasts on the floor or in a back room), so you may need a creative solution. BTL is typically a function of the ignitor, with other ballasts you can get "long distance" ignitors to get around this problem but as far as I know there is no long-distance ignitor for the HQI ballasts (M80 and M81).

But 5 feet is probably not all that bad to work with, just so long as you know that there is this limitation...

cheers