Question, how to change a MH bulb? Dukane 680

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Hey guys, friend of mine is going to be replacing the dukane 680 metal halide bulb. These things are expensive and i'm sure it can't be touched with hands.

How can this bulb be changed. Should you wear special gloves, make sure to discharge the system before installing the light?
What dangers can be avoided?

Thanks guys.

I can't wait to see this system up and running. it's awesome.

You prob. shouldnt get oils from your hands on it like some of the halogens. I dont know though, some MH's have the outer tube, this isnt sensitive to this cause they dont ship it in a sealed box like they do the Halogens, they are more like they standard bulbs are shiped. But this is a MH OHP bulb so who knows. If it cant be touched there will be a notice with the bulb, there always is if it is sensitive to the oils on your fingers. I had residential, wireing and lighting. So in school we had to change the track lights, spot light bulbs etc. All of those we used a clean handkerchief to hold the bulb. They are very expensive bulbs, and held out fine. So either use that method to be safe or get those cheapy disposable rubber gloves used for painting and stuff. Never hurts to be safe!:D
Hehe, long story but. I got shocked by a 220volt water heater, and to make it worse the thermostat was stuck, so she was running at full current draw! Never trust someonelse to make sure the power is off that was the leson I learned. Went to check for continuity at the thermostat and elements "BAP" 220volts at lots of amps. Melted the Multi-meter probes. Blew the probes fuse, melted the plastic to my fingers and my hair was on end with static charge for like 10 minutes. It was one of those jolts that wont let you go, my father had to push me back away, I just couldnt move. So I've been there and no, its not any fun. Plus these MH bulbs run off DC (usually around 90volts 2.2 and up amps) so its twice as bad as being shocked by the same volts AC. Voltage burns, current kills!:(
No matter what electrical thing you are working on practice safety safety safety!! Even a burn from a tiny little 5" lcd flourscent ballast hurts. Always wear gloves when working on high voltages. Gloves should be all you need for removing the bulb from the projector. The reason that you need gloves is that the oils from your hands get on the bulb. When the bulb is fired it heats up the oil on the bulb. It starts to get super hot then creates weak spots on the glass. These could break causing premature bulb failure. Making you have to purchase another $100 bulb :( ouch!.
eebasist said:
you have a multimeter? Thats the first thing i'd use.

Me too. First, since you dont have specs on the ballast you cant just measure resistance for continuity cause you dont know the resistance of the windings in transformer. Be VERY carefull to do this. On the back of the bulb socket are the two wire terminals of course. Hook one end of the probe up to the one wire. Fasten it there so you dont have to hold it (for safty.) Basically you can screw the probe with the wire under the screw terminal on socket. Do this to both sides - and +. Set multi-meter to dc, This will be like 100volts to warn ya so you set meter high enuff, but its at low amps. Then turn on the OHP and get your reading. Check that to the bulb spec. If they match or are within like 10% you are good to go on the ballast end. Does this ballast and bulb have a starter? If so you must match the bulb for that aswell. And thats one more thing to test then also.

Good luck...;)
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