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Author Topic: Exploding HPL stage lamps Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-18-2008 12:11 PM                     Has anybody ever had this problem? We just bought 30 brand new ETC Source-Four PARs (Stage lights.) We unbox them, assemble them and put the lamps in them and, when you go to push it into the socket... POP!! They just explode! We are using HPL-750s from Osram. Again, we are using brand new S-4 PARs and brand new lamps. Everything new out of the box. We are being very careful to press the lamp bases into the sockets slowly and with even pressure. We are sure the polarizing pin is pointing the right way. We blew about 6 out of the original 30 lamps we bought. We ordered 6 more to replace the blown ones. We thought there might be a bad batch so we convinced the dealer (BMI Supply) to send us 6 more, gratis. Out of those six, FOUR of them blew up! Has anybody ever had this happen before? Are we doing something wrong?  |  IP: Logged Paul Mayer Oh get out of it Melvin, before it pulls you under! Posts: 3836 From: Albuquerque, NM Registered: Feb 2000 posted 06-18-2008 12:44 PM                        Wow. Doesn't sound like you or your crew are doing something wrong Randy. I've had just one PAR (a 64) explode on me, but not like you describe. Mine was operating when it went so it was hot. All the rest that failed went just like any other incandescent - no kaboom. Maybe a call to Osram is in order.  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-18-2008 12:58 PM                     Just got off the phone with the rep at BMI Supply. He's issuing a call tag for the four broken HPLs. The only think I can think of is that we got a bad batch or maybe somebody in the warehouse dropped a pallet of them off the forklift, or something like that. I can imagine that, if the ceramic seal around the metal base where the contact pins poke through is cracked or weak, the stress from pushing them into the socket can cause the glass to fracture. The pressure inside the envelope would escape, causing the failure. I've been putting lamps into stage fixtures ever since 8th grade, working on the stage crew. I've always been careful. This has never happened before. If you have the "headlight" style PAR-64 lamps in the "coffee can" style fixture, check to see if the locking ring that holds it in place is pressed too tightly against the glass. It should only be in there firmly enough to keep the lamp from falling out. The lamp should be able to turn freely in place and there should be, maybe a milimeter's worth of "wiggle room". If you put them in too tight, there's no expansion room when the glass gets hot and they will stress fracture while in operation. I had that happen to me one time! And the fixture didn't have the "chicken wire" shield inside it either! Glass came raining down on the stage and landed right on one of the trombone player's laps! That's the kind of shit you only have to have happen ONCE to learn better!  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-18-2008 02:20 PM                     I would point to ETC as the problem. Back when I did dimmer servicing ETC had by far the majority of problems with both fixtures AND dimmer racks... especially with the 4K and larger dimmer modules. Strand and Colortran stuff was far, far more reliable. The Strand fixtures are also much more efficient and the light out of them much more even. We did a shoot out here in SLC for the LSD Church using ETC and Strand PAR fixtures. Strand won by a wide margin. The LSD people went with ETC and have been suffering for their choice... I think the reason they choose ETC was because all got free vacations from ETC back to that LSD town in Illinois where LSD all started. Mark  |  IP: Logged Paul Mayer Oh get out of it Melvin, before it pulls you under! Posts: 3836 From: Albuquerque, NM Registered: Feb 2000 posted 06-18-2008 02:22 PM                        Memories. Used to get the occasional new guy from the hall that would put those locking rings in really tight. Guess who I would get the boss to send up the ladder to focus said instruments? As for my one old-style PAR kaboom, don't know why it went. Never saw one go quite like that either before or since. That can had the wire mesh in it - the mesh and the Roscoe 81 mylar kept the glass chunks/cubes mostly in the can. Otherwise it would have been like a mortar going off. Fortunately that fixture was a backlight (one of several hundred on the set of Starlight Express at the Las Vegas Hilton) and the glass that did fall out didn't cause any problems. Whew. [Edit] My experience with ETC vs. Colortran mid-80's to mid-90's was the exact opposite of Mark's. In the 'Vegas venues I worked (Las Vegas Hilton Main Showroom (Colortran 3000 w/Scene Master 60), Riviera La Cage and Crazy Girls Showrooms (Colortran 1000), Excalibur Arena (Colortran 2000+ w/Scene Master 60)) the desks and racks were pure crap. The only reason so many Colortran installs happened in 'Vegas at the time was because no one else had a sales office in town. I felt sorry for Peterson & Vine having to rep and follow up on all that shit. Plastic ENR-series dimmers with aluminum wire in the racks? Getting called back into the hotel at 3:00am because the desk programmed and played a nice full stage chase pattern all by itself? Oh pulleeze! Funny memories now, but it wasn't appreciated at the time. When I went back to the Hilton in '94 they had put in an ETC desk and racks (either Expression or Obsession - can't remember) and that system ran absolutely great. [ 06-18-2008, 04:56 PM: Message edited by: Paul Mayer ]  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-18-2008 02:47 PM                     We do have the Strand CD-80 dimmer rack in the basement. (192 X 2.4 KW circuits.) We have had virtually no trouble out of them in more than 10 years. A power surge took out the control card one time but, once that was replaced, there have been ZERO problems with them. They are virtually bulletproof! I do like Strands and I like Selicons but our entire light inventory is ETC Source-4. In the S-4 spot light, there used to be problems with the sockets overheating and welding when the lamp wasn't pressed into the socket all the way. ETC upgraded the lamp holders so that there is a spring clip holding the lamp into the socket. Virtually eliminated that problem. The only time we have that is when somebody replaces the lamp without properly latching the clip. In the S-4 PAR, the lamp holder physically clamps the metal base of the HPL lamp in place against the body of the fixture. There is no way for it to come loose and arc like the old version S-4s did. Here's the rub. It is when the lamp is being pressed into place in the lampholder that they explode and NOT when the lampholder is installed in the fixture. The lamps practically burst in your hand! If you're not careful to point the lamp and lampholder away from yourself as you insert the pins you are likely to get a face full of flying glass! Don't know how a bad light fixture could be causing it unless some of the sockets of the lampholders have holes that are out of spec. ??? quote: Paul Mayer Guess who I would get the boss to send up the ladder to focus said instruments? Damn! If our electrics were dead-hung instead of on movable fly lines I'd have to remember that trick!  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-18-2008 05:37 PM                     quote: Paul Mayer My experience with ETC vs. Colortran mid-80's to mid-90's was the exact opposite of Mark's. I wasn't comparing the Colortran and ETC fixtures, just the dimmer racks. We had probably close to 100 Colortran dimmer racks big and small in various schools in Utah and had almost no trouble with them. The racks that had those plastic modules that caught fire though were the biggest pain... that was before my time working in that industry, later ones were trouble free. In any dimmer system dust was always the biggest single factor in reliability. Air availability was the second as the racks required lots of ambient temp. air to run properly. The biggest problem with Colortran's was the airflow sensor and the dimmer moduless filling with dust. If you encountered a dead rack all you had to do was blow on the sensor to clean off the dust and the rack would spring to life. I agree 100% with you on Colortran boards... absolute crap however there were but just a few of them around this neck of the woods. Most boards were Strand. Randy... The later CD-80s are just about as bullett proof as it gets although the early ones are a pain in the neck and parts are just about non existant. Control modules for the later racks are expensive around 5 grand... I saw a few damaged by lightning but nothing else major in the 5 years I worked on them. I also hate the Strand wall conrtrollers used in architectural systems. One jolt of static and it killed them. I have a funny story of the Nuns killing countless Strand Control Stations in the Cathedral here in SLC. They always told me it was a message from God . Johnson Systems a company up in Calgary makes a knock out rack computers to upgrade the old Strand and Electro Control dimmer racks as well as bullett proof wall stations. I installed quite a few of those including retrofitting all the dimming systems at BYU and the U of U. The current Strand boards are the cream of the crop.... extremely expensive... and are what you find most often in use on Broadway shows. The ETC sales folks keep bumping Strand out of the picture in some areas but those people eventually find out what a crock ETC really is... especially those large dimmer modules that always overheat. quote: Randy Stankey Don't know how a bad light fixture could be causing it unless some of the sockets of the lampholders have holes that are out of spec. ??? Too much tension on the contacts in the socket might cause that to happen, what you said about the holes could also be true. More likely the pins on the lamps are too big... Thats if you did not have trouble with lamps in these fixtures in the past. I would see if you could obtain a couple of Ushio lamps of the same type locally and try those and see if the same thing happens. If not then I blame Osram. If the same happens then the sockets in the ETC's are defective. I tend to believe the latter myself. Mark  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-18-2008 11:47 PM                     We got the control module replaced in the dimmer rack on a repair/exchange basis. By the time I got credit for returning the old one, it only ended up costing just shy of $1,000. We also have some CD-80 portables. The only problems we've had in those is the power cubes (SSRs) in a few of them went bad. Since they are portable, we believe it was because somebody stacked them up in a corner, somewhere, where there wasn't enough ventilation. As a result, I bought some extra SSRs and I keep them handy just in case it happens again. Been almost 5 years and haven't needed them yet. I also hate those damn Strand architectural controls! Hate! Hate! Hate! I would like to be able to interface them with the projector automation so that the house lights will fade but, I can only get them to bump up/down. There is no fade setting. Where, exactly do you need to zap them with static to make them die? I would really like to replace the whole dimming system with something from Lutron. Or, do you have a better suggestion? Something I could interface to the movie projector, to the stage lighting console and have 3 wall stations in the auditorium. (Backstage, Front of House and Main Entrance.) On the exploding HPLs... Do you think it could be that the contacts are too stiff or maybe were installed wrong?? Being brand new, they've never had a lamp in the socket. There could be too much resistance as the pins seat themselves in the contacts. After they've been in use for a while, they might loosen up? No? Got a message from the dealer, today. Once the call tag has been issued and he has the old lamps in hand, he said he's going to send us 6 Ushios to replace the Osrams. I kind of like the Ushios but I'm just a bit wary. They have ceramic bases instead of cast metal. I've used them before and they haven't caused trouble. I'm just used to seeing the metal bases like the Osrams have.  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 06-19-2008 10:14 AM                        I am actually going to do a theatrical stage lighting job this weekend! Yay! I havent gotten to do stage lighting since high school. I always liked the Source 4's back in tha day, I dunno I never had any real problems with them. At the High School I went to we had a circa 1976 L.T.I. analog dimming system. We had I think 20 channels and over 100 receptacles on 3 catwalks, and 3 pipes flown above the stage. The board was all analog with 2 busses. Sometimes if we were getting really fancy we would have to re-patch the patch bay on the dimming rack backstage between shows. When I started doing the lights (to get out of class!) the board was located on one of the catwalks. After cleaning out and re-wiring the lighting board receptacle in the abandoned "control room" we moved it up there. We also re-did the entire sound system that had been "broken" for years. I miss those days!  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-19-2008 10:10 PM                     quote: Randy Stankey I would really like to replace the whole dimming system with something from Lutron. Or, do you have a better suggestion? The only good route is with Johnson Systems retrofits. Shaun Johnson is a great engineer and a really nice guy to work with. He is VERY customer oriented too and wants his customers to be happy with his products. I know they have analog wall stations and by now they more than likely have computer based DMX or ethernet wall stations as well. Lutron stuff is pretty sucky too, cheaply made, and some models are dam noisy. Once you install some of the Johnson Systems stuff, especially the rack computer retrofits you'll never want any other brand... they also use nice blue LED's to indicate which switch has been pressed so the wall stations have a nice sparkle to them. The Strand wall stations that are easy to kill are the ones that have the built in microprocessor in them. Static at just about any point wili in front or behind will kill them. For some reason the name of the Strand Architectural system from that era that utilized them escapes my mind. It was a very clumsy system to program. BTW: On the Johnson Systems photo page there is a pic of 4 of the older model CD80 dimmer racks at BYU that I installed the retrofits into. I think the retrofit idea is excellent. The rack, AC buss and and dimmer modules have very little to go wrong... so no reason not to go this route and save money. The racks are completely stripped down and cleaned up. The AC buss connections are checked and torqued down and all dimmer modules cleaned and checked. The new computer and cooling system is installed as well as the dimmer modules. The racks are brought back on line and tested one at a time to verify everything is as it should be... then so on down the line. I think at BYU they saved very close to half a million $$ over installing all new dimming systems. Mark  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-19-2008 10:19 PM                     The System-6 with "Microcontrol" wall stations? Ours is not the digital/microprocessor version. There are two units on the wall in the basement about 18 inches wide and about 2 feet tall. They connect to the wall stations with a 10 volt control line. There is also an interrupt line. When anybody presses a button on one of the other wall stations, it sends the interrupt line high, telling all the other stations on the loop to turn off. That way two or more units don't fight for 1-10 volt control. There is a small theater on campus that still has 110 volt dimmers for lighting control. It was only a year ago when we removed the big variac on the wall and replaced it with ordinary wall dimmers. I'd like to rip the Strands out of the big auditorium and send them to the small theater. Then I'd like to replace the dimmers in the big venue with something better that can be interfaced with the dimmers and the projector automation.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-19-2008 10:23 PM                     Yea, those are analog systems and the Johnson stations would retrofit right in place of yours. They are also pretty inexpensive. In would reccomend that you give Shaun a call and see what he says. Tell him I said hi! Mark  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 06-19-2008 10:35 PM                     This year's budget just ended but I will put them on the list for next year's capital improvements. This year we're probably going to install an IR assisted listening system. Can you believe we STILL don't have one?!  |  IP: Logged

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