Catastrophic lamp failures
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I was doing a lamp check once when one foh unit failed just as i was about to move on to the next channel, it had burned around thirty seconds. i finished the check, got a spare FEL and went up to the catwalk. unplugged the unit pulled the head and inspected the lamp. just a normal blown lamp, slightly warm i just grabbed it and removed it from the socket, set it down on the deck, then turned around to get the spare that i had behind me, BAM!! the old lamp blew as i faced the other direction. the base was the only thing left of the lamp.
no more warm lamp changes for me.
no more warm lamp changes for me.
Edwinlq1go
Member
Edwinlq1go, 4 1/2 x 6 1/2, ie., 50° units. Here's the cut sheet for the 1977 Strand Century Lekolite #2321, 6x9, (oops! wrong generation). See Strand Archive - Leko Range in the Strand Archive. 6x9 was SC#2209 and 4.5x6.5 was SC#2204.
http://www.controlbooth.com/forums/members/edwinlq1go.html
http://www.controlbooth.com/forums/members/edwinlq1go.html
NevilleLighting
Active Member
Every once in a while a lamp blows, just does. That is why most PAR's have a screen. Technically every lamp is supposed to have something between it and the stage, even if the something is a clear gel, although I have no idea what a gel is going to do to stop glass shrapnel. Many PAR's predate the screen requirement and I did get to see one blow during an invited dress with about 800 people in the audience. It showered red hot glass down on to an actress. She kept going but we stopped the show to remove the rest of the broken glass.
Have not tried the SPH 575/115 lamp yet. Got them to play test but have not had time yet. A quick warning went out to me in that lamp's advertising on the other hand: "20% brighter in Par & some" Lekos. That beats the estimate of the now discontinued Osram HPR lamp in being 15-20% brighter in Lekos due to its internal reflector completing the ellipse of the reflector, but on the other hand look at the language Ushio uses. Brighter in PAR and "Some" Lekos. That's a red flag for me before testing in if it says "Some" Lekos... what brand of Leko is it brighter in?
Again have not tried it yet verses the GLC or GLA and what sock I still have in the HPR. This much less verses a GLD and GLE lamp. Could be great but on the other hand in a simple way if you insert a reflector so as to complete that black hole for light inside a reflector assembly I can see a boost in efficiency in the lamp's output. If my lamp specification says on some Lekos it's going to be brighter... my qestion is not as much about how now 20% brighter (fill in the blank as to what in comparison in me not remembering), more simply about that word "Some" as stated in the specification.
While the luminous output of the SPH lamp is 1,000 lumens more than a GLC lammp on paper, I would still ask the vendor to provide both lamps in shoot out with color meter to prove what the assurt given the specifications don't provide this info sufficiently to support their claim. In other words, make the sales person work for his or her profit margin.
Me, I don't know yet in not having tested such lamps. I do know that the Osram lamp now is supposted to be as good as the Philips GLC lamp in them having done an upgrade to it. GE/Thorn in specification seems low in what's published in output for the lamp.
Beyond all this, and way back on the forum back to HX-600 lamps as compared to FEL lamps, the HX-600 lamp at 575w/115v as compared to a FEL at 1Kw/120v is like a 800w lamp at a higher color temperature as compared to a 1Kw lamp at a lower color temperature.
Same though with better optics with a HPL lamp. Not persay more light and indeed a FEL was a terrible in efficiency lamp, more about that higher color temperature in making it seem brigher than the FEL.
For actual output one more would want to go with a 750w/115v lamp in getting close to output but with more refinened filament so the light produced gets out of the fixture in being brighter plus having that higher color temperature. On the other hand, if one can have less light and be satisfied, that's another fixture per dimmer you can install on it and go with the 575w lamps. Stages are too bright these days most often anyway. The FEL for instance is not designed for a 360Q, while it could be used in say a less efficient fixture so as to pump out enough light.... not for a 360Q and to some extent while it in a 360Q
did pump out a bit more light it also trashed more and more fixtures in doing so.
This heck, I got this 1.2Kw lamp that will function in a 360Q or other fixture for sheer output. Filament ain't very refined but one can use in in being powerful enough granny needs to wear shades when coming to the show.
So the above question of the SPH lamp... Go Ushio if it's better than a GLA in not having to go GLD in wattage, but on the other hand I would play test such a theory given the advertisement. Goal is more output and a higher color temperature and efficiency so as to make it seem more intense yet, but still get say four fixtures per dimmer. That's the goal in not having to exceed more and more in excess. Sure say a 750w lamp persay if competing with moving lights or 1Kw lamps in general but if on stage hopefully the 575w lamp if not the long life version of it is sufficient.
Compared to what often the qestion in "percieved" intensity.
Balance in general between color temperature and luminous output in being more given voltage but lamp hours being less for the most part in concept in balance. Four things to balance for the most part in lamp design.
That's in general for lamp design on the other hand. When a lamp is designed for a lighting fixture on the other hand such as the HPL lamp or the new 1Kw AlumiPAR lamps designed for PAR 64 fixtures I was told are TBA to the market really soon, in those cases it's less about the above standards in a filament can only get up to like 3.5K or 3.6K in output before melting thru out of limitation before one considers, yes you have a filament and it has X amount of output as its own limitation before some liquid filled halogen/xenon fluid works with the filament lamp in allowing the filament to operate a higher color temperature and luminous intensity as per projector lamps already using such concepts.
What the HPL lamp and in general grid or stacked filaments allowed in given current limitations of the above voltage, output, colortemperature and lamp life did for the industry was an addition of smaller fillament cubic size needed for what was stable in design otherwise in working. Instead of a linear filament, we get a stacked filament or one on a grid that is designed with high technology so as to prevent arching between filament coils but also small enough in size that you get closer to that "Point source of light" design concept with any Leko ellipsoidal reflector spotlight.
That's the basics in lamp design. Lower the voltage of the lamp to more match that found at the fixture after voltage drop, lower the lamp life some and smaller the size of the filament and you get the HX-600/HPL lamp technology for the most part. More light gets out both by way of smaller cubic area of point source of light and operating voltage of the filament in operating at a closer voltage to what the fixture is seeing in reality.
The HPR lamp while a bad design in going FLK instead of more efficient filament GLC was an interesting design development none the less even if mistake. Such a lamp had a reflector inside of the lamp much like that of the FEL/R lamp that's long discontinued but also had an internal reflector. Such lamps and filaments were what they were but they had a reflector inside the lamp that sort of filled in that hole inside the reflector taken away from the reflector needed to insert the lamp within. It was in adding efficiency without heat if not even removing some lost heat, a more efficient but I'm told very difficult thing to do in adding this simple reflective plate into the lamp.
Still though there is ways to add to lamp efficiency.. Xenon gas goes further in allowing for a higher operating temperature within the lamp. Many halogen lamps already have the xenon gas within it. Some way of doing a liquid filled halogen/xenon filament lamp makes lamp makers sweat in their sleep in instantly asking about who is doint it already I think. Smaller filament cubic areas than next after completing the ellipse.
Found it fascinating recently an article about tubular lamps like work light T-3 4.11/16" lamps that instead of needing a bunch of filament hangers for them, they found a way to instead pinch the globe of the lamp to support the filament instead to support the filament. There is technology out there and no word on GE's appairent two year old upgrade to the HPL, but all is coming, much less many manufacturers count the days until the pattent on the HPL is gone before they both improve it and improve all lamps.
SPH potentially good. Try it. I don't know.
Please do. We love pictures and shoot-outs. But it might be best to post your results to this thread: http://www.controlbooth.com/forums/lighting/6751-ushio-releases-sph-575watt-115volt-lamp.html.
Suggestion for a replacement for FELs
Hi,
I read this thread yesterday and joined today to get some advice.
I just purchased 2 (very used but in good condition) Strand 2212s that came with FELs. Their application will be front lighting in a music school performance space. The throw is probably about 20-25 ft. They will be mounted in the back corners of the room around 11ft off the floor. They will be gelled w. something like pale amber or pale pink.
500w would probably be enough and I could put them both on the same circuit (different dimmers) however 750w would give me some 'headroom.'
What is the recommendation for a replacement. Longer life is good.
Thanks,
Ray.
Hi,
I read this thread yesterday and joined today to get some advice.
I just purchased 2 (very used but in good condition) Strand 2212s that came with FELs. Their application will be front lighting in a music school performance space. The throw is probably about 20-25 ft. They will be mounted in the back corners of the room around 11ft off the floor. They will be gelled w. something like pale amber or pale pink.
500w would probably be enough and I could put them both on the same circuit (different dimmers) however 750w would give me some 'headroom.'
What is the recommendation for a replacement. Longer life is good.
Thanks,
Ray.
Re: Suggestion for a replacement for FELs
Either of these would be fine.
ANSI Watts Volts Temp Life Lumens Price
GLA 575 115 3050 1500 13000 $18.25
GLE 750 115 3050 1500 17400 $25.90
Compare with the first generation of this lamp family.
EHD 500 120 2950 2000 10450 $17.16
EHG 750 120 3000 2000 15000 $15.55
Either of these would be fine.
ANSI Watts Volts Temp Life Lumens Price
GLA 575 115 3050 1500 13000 $18.25
GLE 750 115 3050 1500 17400 $25.90
Compare with the first generation of this lamp family.
EHD 500 120 2950 2000 10450 $17.16
EHG 750 120 3000 2000 15000 $15.55
gordonmcleod
Active Member
Re: Suggestion for a replacement for FELs
Not an FEL, in fact, only a 500W lamp, but of the same family and one of the most interesting lamp failures I've ever seen:
from Jim On Light .
One could speculate about this with many hypotheses.
Not an FEL, in fact, only a 500W lamp, but of the same family and one of the most interesting lamp failures I've ever seen:
from Jim On Light .
One could speculate about this with many hypotheses.
- Since in a Fresnel, the lamp burns base down, all the heat is concentrated at the end of the envelope.
- Because of the spherical reflector, all the heat is concentrated on one side of the lamp.
- The coiled-coil filament geometry doesn't suit itself well to a spherical reflector. A planar filament, such as on the BTL family, makes much more sense. But using an EHD is not unique to Kliegl; Altman used the same lamp in some of their 6"FS (65Q) for a time.
- What chemical compound would cause the yellow powder on the inside of the envelope? Sulfur?
- What caused a portion of the filament to get sucked outside the envelope?
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Consider that the lamp would contain a halogen (Flourine, Chlorine, Bromine, or Iodine), it could be a reaction between one of those with possible skin oils if someone did a bad job changing the lamp or some other foreign item that cause the yellowness to occur.
Indeed, a very strange lamp failure.
Indeed, a very strange lamp failure.
Re: Suggestion for a replacement for FELs
Since explosive decompression has time and time again been disproved by Mythbusters one can assume that it was explosive compression that blew it out of the lamp as opposed to it being sucked out.
Re: Suggestion for a replacement for FELs
stagelightinc's Channel - YouTube
Speaking of the busting of myths, some may find this video enlightening.
stagelightinc's Channel - YouTube
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