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View Full Version : do halide bulbs "blow" like regular household light bulbs?


Capt_Cully
07/25/2006, 02:59 PM
I've got a 2x 250w de hqi fixture. Yesterday the GFI attached to them clicked off. Not sure what caused the surge. But, when I reset it and turned my halides back on, only one of them lights up.

Do they blow out like regular household bulbs break their filament?

Thanks

manderx
07/25/2006, 03:33 PM
it could be the bulb or ballast. easy enough to figure out, just swap the bulbs. i'd guess ballast, maybe the ballast blew which tripped the gfci?

Capt_Cully
07/26/2006, 07:29 AM
I would have just checked the bulb but it would require some significant tear down. but as it turns out, i just turned off the ballast for a day until I had time to figure it out. I tried it one more time and both bulbs came back on. ?????

Go figure. Thanks anyway.

seattlerob
07/26/2006, 08:10 AM
Hey Capt_Cully: I also have 2x250w HQI pendants, attached to a single blueline ballast. I have also experienced only 1 bulb coming back on after power interruption. I think what you're experiencing is a power-up issue related to heat. I believe if MH is turned off & then turned back on too quickly (i.e. while the ballast is still hot or very warm), the bulb(s) may not come on until the ballast is below a certain threshold.

This is my speculation on what I've observed with my setup. In the few cases I've had, time has been the cure for the 2nd bulb to come online.

HTH,
Rob

jmaneyapanda
07/26/2006, 08:36 AM
That is correct. If a MH bulb is powered off, you want it to cool before restart, or it probably wont fire, and will likely decrease lamp life. Many controllers have safeties for this now. I know the Reefkeeper has a "SUre start" feature that will wait like 15 minutes aftyer power is lost to retsart the MH bulbs to ensure this safety.

BTW, halides dont have filaments, so they wont break like that.

Capt_Cully
07/27/2006, 11:30 AM
thanks all