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#11190 07/07/02 09:13 PM
Joined: Jul 2002
Posts: 74
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Sorry RMIESQ, I butchered your name.

#11191 07/08/02 08:54 AM
Joined: Dec 2002
Posts: 30
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Junior Member
No Problem

#11192 07/08/02 09:23 AM
Joined: Nov 2001
Posts: 745
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Bob: Looks like you have other options available to you of which I wasn't aware. Glad these other guys here have given you some help.

Mike (mamills)

#11193 07/08/02 11:33 PM
Joined: Jun 2001
Posts: 196
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Member
webmaster, i hope bob makes sure his smoke alarms are working and are in the right places until its fixed, guess i'd worry even more about what might be on the floors below, and next door too, that i didn't know about ---- scary, maybe they should sleep in shifts, but smoke alarms really sound important to begin with........... and i hope they don't leave pets there when they're gone

#11194 07/09/02 12:11 AM
Joined: Apr 2002
Posts: 2,527
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Moderator
In the mean time, I would keep closest watch, feel and smell of the plug-fuse faces and cord connectors—offhand, I'd say they are likely the weaker spots.

#11195 07/09/02 02:04 AM
Joined: Oct 2000
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Cindy,

Good Advice!
I hope that 'Bob' is following this thread too. If not, I hope it may be providing some information and ideas for someone else that may find themselves in a similar situation and is not sure what to do.

#11196 07/10/02 11:04 AM
Joined: Nov 2001
Posts: 745
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Member
"feel and smell of the plug fuse faces..."

Bjarney: Have you (or anyone else, for that fact) seen a 30a. plug fuse that had so much current passing through it that it was not only fiery hot to the touch, but the fuse link inside was actually GLOWING? [Linked Image] I kid you not, when I was in high school and working the projection room of a local movie theater, there was a large fuse panel. The panel was so hot that the cover could not be put in place. lest the panel overheat (as if it wasn't already). The wire (12awg) connected to the particular fuse in question was every bit as hot as the fuse.

Mike to Manager: what about this?
Manager to Mike: Forget about it. Do your job (putting it nicely).

I quit a week later. A late night electrical fire gutted the projection room of the theater about 6 weeks after. Fortunately, the theater was closed for the night.

Mike (mamills)

#11197 07/10/02 02:56 PM
Joined: Apr 2002
Posts: 2,527
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Moderator
"...fire gutted the projection room of the theater"

Sorry Mike, not found anything quite that bad on this end. Incandescent {glowing} plug fuses probably would have preoccupied me too. If you could see “red” under those conditions, I’d bet the panel was “slugged” with copper pennies behind the plug fuses. I can’t imagine the fusible alloy maintaining circuit continuity [internal to the fuse itself] survive being heated to that extent . I have a “laurel wreath” [ie, old] penny with melted—once-liquid—arc marks that I found in an attic from which I exited rather quickly. The back of its porcelain cutout had been hot enough to melt and cause to drool the ceramic-based insulating cement behind the cutout’s screwshell.

Your account of the fire incident is even more unusual, in that old projection rooms were most often made as fire- and ”bullet”-proof as could be. {I’m certain in virtually all cases that meant a pile of asbestos used in the room’s construction.} Earlier in the twentieth century, the rationale behind all the extra efforts at protection of this type of room was that they routinely stored photographic film made from cellulose nitrate, which is roughly equivalent to gunpowder in energy release during deflagration following ignition.

“Unless stored at a very low temperature, cellulose nitrate motion picture and still photographic film (also known as nitrate) self-destructs at an unpredictable rate over time. As it deteriorates, nitrate gives off acidic by-products (nitric oxide, nitrogen dioxide). These acidic gases are deep lung irritants. Repeated exposure may cause eye irritation, rashes and sores on the face and skin, vertigo, nausea, headaches, swollen glands, and respiratory irritation. By-products from nitrate film also damage surrounding museum materials causing embrittlement of paper and film and cumulative damage to many organic materials and metals. Deteriorated nitrate film is highly flammable and can burn under water. Once ignited, nitrate fires are almost impossible to put out. The toxic gases produced by burning nitrate are lethal. Nitrate should not be stored in general museum, archival, or office spaces.” http://www.cr.nps.gov/museum/publications/conserveogram/14-08.pdf

#11198 07/10/02 03:56 PM
Joined: Nov 2001
Posts: 745
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Member
Bjarney: That always puzzled me, too. I never could figure out how the fuse element could get that hot, yet still remain intact. The suspicion that this fuse, and probably numerous others, were slugged, is about the only sensible explanation. I never tried to remove the fuse or examine it...too hot.

This incident being over thirty years ago (1971), I don't really have a clear recollection of how the room was constructed. I do remember that, beside non-flammable film stock (which was stored in a large metal cabinet) the room contained various other pieces of electrical switchgear, a generator set (for supplying D.C. Current to the carbon arc lamps), two 35mm projectors, and a small wall-mounted rack containing the sound system amplifiers, as well as a table and a couple of chairs. Seemed like the floor of the room was made of concrete, but the walls and ceiling were plaster on wood lath, with numerous penetrations for conduits and exhaust vents from the arc lights. The rear wall of the booth (AKA the front wall of the building) also contained a small window. If I'm remembering correctly, a police officer on patrol noticed fire venting through this window, whereupon he called for help. After repairs and rewiring, the building reopened about six months later. I never did see the room again, either following the fire, or the reconstruction. The building was condemned and demolished almost two years ago due to a major structural failure in the roof.

Mike (mamills)

[This message has been edited by mamills (edited 07-10-2002).]

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