"Short arc bulbs" - bad idea?

[SophiaRodriguez]

Hi everyone

I purchased 2x used Martin MAC 2000 Performance II fixture, which uses one of the two bulbs:

"Philips MSR Gold 1200 SA/DE 1CT/4" (preinstalled)​

https://www.lighting.philips.com/pr...-gold-sa-double-ended/928099605115_EU/product
OR "ORSAM SHARXS HTI 1200 W/D7/60" (approved alternative)
https://www.osram.com/ecat/SharXS HTI-SharXS-Discharge lamps-Entertainment-Specialty Lighting/com/en/GPS01_1028452/ZMP_56307/

My questions:
1) On the Philips bulb website it says:
"Life to 50% Failures (Nom): 750 hours".
Does it mean that about 50% of the bulbs around 750 hours or so the bulb stops working?

2) Does anyone worked with this bulb on a regular basis? How often do they die, and after how many hours?

3) Do those bulbs explodes frequently? did anyone had experience with this bulb exploding?

4) If those bulbs explode in a middle of the show, do I have to evacuate the theater?

5) Which bulb is "better" (if any)? the Philips or the ORSAM one?

Thank you so much!!

Sophia

 

[almorton]

That's about the usual life for short arc lamps. They can explode on failure, but it's not exactly common. If one pops in the fixture it should be contained, and evacuating the theatre is not usually a requirement - just like any other lamp failing catastrophically. Both manufacturers are good; I've only used Osram Sharx lamps (the 400W ones, in Mac550, so different ) in our fixtures ,and they've been just fine.

 

[SophiaRodriguez]

That's about the usual life for short arc lamps. They can explode on failure, but it's not exactly common. If one pops in the fixture it should be contained, and evacuating the theatre is not usually a requirement - just like any other lamp failing catastrophically. Both manufacturers are good; I've only used Osram Sharx lamps (the 400W ones, in Mac550, so different ) in our fixtures ,and they've been just fine.

Thank you so much!!

Sophia

 

[ship]

I have years and thousands of lamps experience on that fixture type. And I am talking thousands of lamps on that fixture type worth of experience. Yes, verified, I can tell lamp failure cause and or within 100 hours how long that lamp was in use normally. That level of experience with a magnifying glass each and every lamp used.

First read the Mac 2K manual especially about lamp socket replacement needs after every three lamp changes. This is not something to ignore or often the perfectly good lamp into a growingly bad lamp socket will last 100 hours less per lamp until they stop working. Lamp sockets in this dual ended fixture type go bad - if you see a burned in tattoo on the bad lamp removed... that came from the lamp socket, you should probably replace it also. etc. like not just scratches but gouges in the lamp base. A clean not discolored or scratched current flow in smooth contact points. Back in the way back machine I had a theory about the spring steel in the lamp sockets becoming tempered. What ever the case, leading cause of lamp failure is not living up to it's life, but bad ballast or components. Be glad this fixture at least goes to half output mode when the fixture is doused... the VL-3K had problems with heat in using the same lamp but not doing so.

Between the Philips and Osram lamps... Osram was cheaper and more dependable. Initially, the Philips lamp had dependably issues once you got into higher lamp hours. And the cost.

For tour's exploding lamps was not much a problem and something to service, but have doccumented lamps at over 3,000 hours. That said the lamp was working but not efficiently - it was like a fluorescent lamp doing the gobo's or what ever in use. Should have been replaced. Back to the "Walking with Dinosaurs" tour I did most of my studies on... that Willie' tech person who called his lamp replacements "crack pipes", but never changed lamp sockets... "Crack Pipe Willie". Endless emails to the tour so as to educate or remove this this person didn't add up to anything. He would constantly put perfectly good lamps into bad lamp sockets.

In the end, corporate who wanted to use lamps well beyond the 750 hour expected lamp life based on really old mover fixtures, I got to agree on a 1,000 hour lamp change standard. Blown up lamps between the 750 and 1,000 hour range was rare short of other factors. All lamps at 750 hours were as termed, fairly "snowball" and crusted/etched globe of the lamp thoroughly in demisted point source or light output. At 750 hours you should replace the lamps, just because they are not doing their jobs and causing heat problems systemic.

1) I think the lamp rated life expectation was mis-understood. 10% if I remember.
2) above
3) These bulbs (lamps) a bulb is something you plant!!! Do explode at times, why is more an issue than worry about as above contained fixture. A well maintained fixture and management of hours should not have bulbs exploding. Why it would explode is after audience, yes safe next question.

4) No not evacuate the theater, as said above, self contained... just have to figure out how to deal with one less fixture in design until you can change the lamp - only reason with bad lamp socket, to put a good lamp into it... after that, that lamp installed should never be used again or it will corrode a good lamp socket.

5) Which lamp to use... as a retailer and end user, but a standard on this website I would not advise which brand. Philips has gone up a lot on quality of lamp reliability. Both have seemingly over the years become reliable. And there are other brands last I knew like Koto and others for the lamp if fair. Would have to go back into my notes for alternate suppliers if wanted.

 

[SophiaRodriguez]

I have years and thousands of lamps experience on that fixture type. And I am talking thousands of lamps on that fixture type worth of experience. Yes, verified, I can tell lamp failure cause and or within 100 hours how long that lamp was in use normally. That level of experience with a magnifying glass each and every lamp used.

First read the Mac 2K manual especially about lamp socket replacement needs after every three lamp changes. This is not something to ignore or often the perfectly good lamp into a growingly bad lamp socket will last 100 hours less per lamp until they stop working. Lamp sockets in this dual ended fixture type go bad - if you see a burned in tattoo on the bad lamp removed... that came from the lamp socket, you should probably replace it also. etc. like not just scratches but gouges in the lamp base. A clean not discolored or scratched current flow in smooth contact points. Back in the way back machine I had a theory about the spring steel in the lamp sockets becoming tempered. What ever the case, leading cause of lamp failure is not living up to it's life, but bad ballast or components. Be glad this fixture at least goes to half output mode when the fixture is doused... the VL-3K had problems with heat in using the same lamp but not doing so.

Between the Philips and Osram lamps... Osram was cheaper and more dependable. Initially, the Philips lamp had dependably issues once you got into higher lamp hours. And the cost.

For tour's exploding lamps was not much a problem and something to service, but have doccumented lamps at over 3,000 hours. That said the lamp was working but not efficiently - it was like a fluorescent lamp doing the gobo's or what ever in use. Should have been replaced. Back to the "Walking with Dinosaurs" tour I did most of my studies on... that Willie' tech person who called his lamp replacements "crack pipes", but never changed lamp sockets... "Crack Pipe Willie". Endless emails to the tour so as to educate or remove this this person didn't add up to anything. He would constantly put perfectly good lamps into bad lamp sockets.

In the end, corporate who wanted to use lamps well beyond the 750 hour expected lamp life based on really old mover fixtures, I got to agree on a 1,000 hour lamp change standard. Blown up lamps between the 750 and 1,000 hour range was rare short of other factors. All lamps at 750 hours were as termed, fairly "snowball" and crusted/etched globe of the lamp thoroughly in demisted point source or light output. At 750 hours you should replace the lamps, just because they are not doing their jobs and causing heat problems systemic.

1) I think the lamp rated life expectation was mis-understood. 10% if I remember.
2) above
3) These bulbs (lamps) a bulb is something you plant!!! Do explode at times, why is more an issue than worry about as above contained fixture. A well maintained fixture and management of hours should not have bulbs exploding. Why it would explode is after audience, yes safe next question.

4) No not evacuate the theater, as said above, self contained... just have to figure out how to deal with one less fixture in design until you can change the lamp - only reason with bad lamp socket, to put a good lamp into it... after that, that lamp installed should never be used again or it will corrode a good lamp socket.

5) Which lamp to use... as a retailer and end user, but a standard on this website I would not advise which brand. Philips has gone up a lot on quality of lamp reliability. Both have seemingly over the years become reliable. And there are other brands last I knew like Koto and others for the lamp if fair. Would have to go back into my notes for alternate suppliers if wanted.

I really appreciate your detailed reply!!

Sophia

 

[ship]

A lot of tech people I work with disliked that line of fixture. I'm sure others can chime in on the reasons. It had issues in growing up like all fixtures, but certainly not as many as others of the same age or after. I think if after timely ballast replacement and various upgrades, care to the lamp sockets... should work fine if venerable but maintained.

 

[SophiaRodriguez]

A lot of tech people I work with disliked that line of fixture. I'm sure others can chime in on the reasons. It had issues in growing up like all fixtures, but certainly not as many as others of the same age or after. I think if after timely ballast replacement and various upgrades, care to the lamp sockets... should work fine if venerable but maintained.

Thanks!

Sophia

 

[DELO72]

OSRAM are way better! (*smirk*)
Philips just discontinued their lamps of this type, so once the stuff already in the market is gone, you won't really have an option. But- as I stated in the sentence above.... ;-)
Lamps have what is known as an "Average Rated Lifetime". That means that when we make lamps we turn them on in a burning cycle, and they start to fail at some point, one by one. The point at which 50% of the test lamps have turned off and failed is what is called the average rated lifetime. Some lamps will continue burning beyond that time. Some will die before that time. Expect ~750 hrs. on average. Because lamps also get cloudy (the quartz divitrifies as it ages or with heat), they emit less life over the lifetime. This is why some Shows/Companies replace their lamps earlier than that (Cirque du Soleil for instance replaced theirs at 50% of the life rating), to ensure each is providing full output and the lighting cues look the same show-to-show.

The lamps do contain minute traces of mercury, but it solidifies very quickly once it cools. Someone would only be at risk if their face was right next to the fan outtake of the fixture when the lamp exploded. And mercury is really only a danger if inhaled or ingested while it is in gas form.

 

[SophiaRodriguez]

OSRAM are way better! (*smirk*)
Philips just discontinued their lamps of this type, so once the stuff already in the market is gone, you won't really have an option. But- as I stated in the sentence above.... ;-)
Lamps have what is known as an "Average Rated Lifetime". That means that when we make lamps we turn them on in a burning cycle, and they start to fail at some point, one by one. The point at which 50% of the test lamps have turned off and failed is what is called the average rated lifetime. Some lamps will continue burning beyond that time. Some will die before that time. Expect ~750 hrs. on average. Because lamps also get cloudy (the quartz divitrifies as it ages or with heat), they emit less life over the lifetime. This is why some Shows/Companies replace their lamps earlier than that (Cirque du Soleil for instance replaced theirs at 50% of the life rating), to ensure each is providing full output and the lighting cues look the same show-to-show.

The lamps do contain minute traces of mercury, but it solidifies very quickly once it cools. Someone would only be at risk if their face was right next to the fan outtake of the fixture when the lamp exploded. And mercury is really only a danger if inhaled or ingested while it is in gas form.

So helpful, thank you very much!!

Sophia