# Make sure you unplug the right lamp....



## willbb123 (Oct 4, 2009)

We just had a rental loadout, there were some contract problems so they didn't restore the lighting plot. 30 min before house opening I decided that I wanted to restore color in my first electric. 

We got the gel and scrollers up in 20 min, then I checked lamps and saw that a s4 par was burnt out. Still rushed I walked up to it and unplugged what I thought was the light. As soon as the new lamp made contact with the sockets it came on. Out of habit I had the foam packaging between it and my fingers and my hand. I would of not been very happy if I was holding the lamp or wearing gloves.


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## edmedmoped (Oct 4, 2009)

Ouch......


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## photoatdv (Oct 4, 2009)

One of our techs would usually re-lamp without unplugging it... apparently if you hold the base just right, you have just enough time before it roasts your hand to get it in...  . I don't know why or how he'd do this... but I don't plan on trying it. Relamping a light that is still hot (not room temp) wearing leather gloves is fun enough for me.

Hope your hand's okay there Will.


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## Les (Oct 4, 2009)

photoatdv said:


> One of our techs would usually re-lamp without unplugging it... apparently if you hold the base just right, you have just enough time before it roasts your hand to get it in...  . I don't know why or how he'd do this... but I don't plan on trying it. Relamping a light that is still hot (not room temp) wearing leather gloves is fun enough for me.
> 
> Hope your hand's okay there Will.



Hmm, sounds like a great way to toast _not only your hands but also_ lamp bases to me!


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## photoatdv (Oct 4, 2009)

Yeah, I wondered about that one... but I've seen pros do it too... so I figured it couldn't be too bad.


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## Les (Oct 4, 2009)

photoatdv said:


> Yeah, I wondered about that one... but I've seen pros do it too... so I figured it couldn't be too bad.



Well if that's the way the pro's do it then it _*must*_ be right 

>>They usually rent the gear they're using.


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## MillburyAuditorium (Nov 21, 2009)

Well, I wasn't here for this but I was told of it,

I wasn't there one day and the person I have been teaching decided to put the name lamps in the FOH spots we just got in because some had burnt out. So he leaves all of the FOH spots on about 20 percent, didnt unplug anything, used a plastic bag to hold the lamp dumb me, told him never to touch hte lap, but not to touch it with..., So he plugs it in it comes on, bag melt and I guess we had a little camp fire for a few minutes before someone ran up and shut off hte lights.

He waited for me to do the rests


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## PeytonJr (Nov 21, 2009)

This same thing happened to the other intern at the theatre I worked at over the summer. While cleaning the gunk off the lamp, the LD told us a morbid tale-
His friend went to go re-lamp a fixture and turned it off, unplugged it and everything, but apparently it had been on for a while and was still considerably hot. When she grabbed hold of it to take it out, it exploded and she lost a pinky. :shock:


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## photoatdv (Nov 21, 2009)

And that's why you wear thick leather work gloves when removing recently lit burned out lamps ladies and gentlemen...


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## Soxred93 (Nov 22, 2009)

Make sure you plug in the right lamp too...

At a production we finished recently, we had 2 specials focused directly above two people. They would be the only lights on at the time, so the people under them would have like a holy "halo" effect. On the dress rehearsal, we see that one of them failed, so only one person was lit. After the first act was finished, we replaced the lamp and put it back in the instrument. We turn on the channel, and it works. 

The next night at the show, we go to the cue again. However, once again, the light didn't go on. We're confused as to how it didn't work, until we saw that it was plugged into the wrong circuit. D'oh!


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## Sony (Nov 24, 2009)

I've done this before by accident, was in a bit of a rush and had to replace a BTN in an Altman Fresnel and forgot to unplug it, melted the foam to the lamp. It's actually fairly common, and no I don't ever recommend changing lamps while the fixture is turned on, no matter how skilled you are.


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## dramatech (Nov 24, 2009)

I still unplug the fixture, to relamp, but just a little trivia. All of my Selecon fresnels and broads, have microswitches that open the line to the socket, when they are opened to change the lamp. Both of the lines to the socket are switched open.
Talk about a clever safety function!


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## church (Jan 31, 2010)

the other thing to remember is that if you leave the fixture plugged in when you change the lamp you also risk damaging your eyes from the UV and the intensity of the light from the lamp when the burner assembly is removed from the fixture of the lens door is open.


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## chris325 (Jan 31, 2010)

All in all, a fixture should _always_ be unplugged before one changes a lamp. The risks are way too high to save a few seconds from not unplugging it.

The horror stories described previously (specifically the explosion one) should fully substantiate my reasoning.


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## photoatdv (Jan 31, 2010)

Agreed-- there's no reason to change lamps hot. However church I think you're thinking of Arc lamps-- while incandescent do give off UV, it's not usually a huge problem. While I don't (and never *intentionally* have) changed a lamp hot, I've worked with them without the lenses or even the lamp cap entirely removed from the fixture. Note-- this generally was for a specific reason and I was wearing gloves, ect and definitely wasn't staring at the lamp.


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## zuixro (Jan 31, 2010)

I believe there is actually a coating on the lamp that filters out UV. I think I read that somewhere on here.


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## mamills (Mar 5, 2010)

In our theater, we take several precautions when re-lamping- 1) an electrician unpatches the circuit at the dimmer rack and double checks the circuit number, 2) the electrician changing the lamp disconnects the instrument at the plugging box before relamping - if there is *any* difficulty in removing the lamp. the instrument is un-hung and brought down to the deck (probably ought to be done more frequently anyway, since it receives a good cleaning at this point), 3) the electrician completely closes the instrument before reconnecting to the plugging box, and then 4) the electrician reconnects the circuit at the dimmer rack before powering up the instrument - if the instrument has been brought down to the deck, it is powered up at a floor pocket to burn in, then taken back to its hanging position. We have had cases of new un-burned lamps exploding on power-up and always take as much time as necessary to eliminate/mitigate this hazard as much as possible (including thoroughly wiping down a new lamp before burning). Other personnel in the theater become irritated on occasion because of the time we take for this, but we make it abundantly clear to them that our safety is well worth a little inconvenience on their part and we will not deviate.


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## photoatdv (Mar 5, 2010)

Okay... I'm a wee bit confused. If the instrument being worked on is unplugged, what purpose is there to unpatching the dimmer rack?

Good practice to put it back together before plugging in ... and wiping down lamps. However, I don't really consider exploding incandescent lamps safely within the housing a huge hazard to personnel...


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## chris325 (Mar 5, 2010)

mamills said:


> We have had cases of new un-burned lamps exploding on power-up and always take as much time as necessary to eliminate/mitigate this hazard as much as possible (including thoroughly wiping down a new lamp before burning).



How often has this happened? I've only seen it happen twice - I discovered the shattered remains of a lamp in a fixture while hanging it, and I did see one suddenly go super bright and then go out, but the supernova wasn't big enough to do anything but morph the lamp a bit.

As for wiping down the lamp, is it really necessary if the lamp has not touched anything but the foam it came in? The only defect I've ever seen upon opening the box of a lamp is a broken filament (it's incredibly annoying how fragile FELs are.)


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## masterelectrician2112 (Mar 6, 2010)

chris325 said:


> As for wiping down the lamp, is it really necessary if the lamp has not touched anything but the foam it came in?



I would guess not. I have never wiped down a lamp before relamping. I just try not to touch the lamp before using it.


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## church (Mar 22, 2010)

zuixro said:


> I believe there is actually a coating on the lamp that filters out UV. I think I read that somewhere on here.



Normally the lens in the front of a halogen lens acts as a U.V. filter however when the fixture is open this is removed and your eyes are very close to the light source within a couple of feet unless you have extremely long arms. Just to quote from the OSRAM instructions that come with each of their Halogen Display/Optic Lamp's ( in this case a BTH):

_"This bulb must be used in a fixture that has a suitable screening technique to protect people and surroundings against the risk of personal injury and/or property danmage from bulb shattering and UV exposure, since:
1) .....
2) the bulb generates UV (ultraviolet) radiation that may cause skin and eye irritation with prolonged exposure.
* to avoid risk of serious eye injury from the intense light do not stare at operating bulb"_

Agreed the risk may be low but you only get one set of eyes so why take the risk and if you are the ME responsible for supervising staff and a problem occurs because someone relamps without unplugging you are now in the spotlight (pun intended) with OSHA or the Ministry of Labour or whoeve deals with this stuff where you are working.


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## WooferHound (Apr 22, 2010)

You didn't really want those fingerprints anyway, did you


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