E-39 Lamp Socket Problem


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Ran into an interesting - ok... pissing off problem today while prepping some new High Bay Metal Halide lights for a show - leaving today. Work on them was going well, should have been done early this morning.

- 5 voltage taps - tap the proper marked line to 120v, cap splice off the rest. Didn’t think of doing high temp. heat shrink wire caps on the un-used tap wires until later, but the nylon cover on the extra tap wires will be fine given the separate from the lamp ballast cavity.

- Replace all other high temperature wire nut connections with either high temperature butt splices with three layers of Scotch #69 fiberglass electrical tape, or in the case of multi-wire connections, a crimped #10 ferrule and McMaster #6877k7 high temperature wire nut with set screw & high temperature cable tie for support of the wire. Such wire nuts have never been known to come off the connection when properly done. Was my 1st assistant and I only doing the wiring & have been doing this method for 20 years now on stuff like Mole lights.

- Find hard points on the frame sufficient & balanced to mount a yoke. Thick plates to mount the yoke sandwiching the cast aluminum shells of the ballast frame & bent around corners so as to provide a good safety cable loop strap ring. No mounting bolts near electrical parts. Side-lock nuts or flex top nuts dependant on where with external tooth lock washers used instead of any Nylock nuts. Lock nuts properly rated for heat.

- Install longer screws to assemble to fixture for use of top lock or flex top nuts dependant on where in ensuring the frame can not fall apart.

- Lanyard bolted to the reflector with snap hook attached to safety cable loop.

- Other details - lever location adjustment handles, Fiber washers under the Cheseboroughs, 90 degree elbow cord grips so the cord cannot get fouled by the yoke. Many man/hours and a lot of extra money spent to make these architectural fixtures tour ready.

Doubt the Euro leg of the tour went to this much effort! Did they forget to bring the fixtures... or were they falling apart and not taken. Oh’ by the way, they didn’t mention a need for these and some similar HPS parking lot lights until last week. ?Know how hard it is to find parking lot or high bay fixtures in a rush which are not LED these days??? Designer loves the warm up curve for them - thus the use and different fixture types for a song.

Others found the fixtures on time - I was at a brick wall, I got the lamps. All was going well in even getting them early and assembly was on-time. First fixture done early this morning.... No strike! Here is another done fixture... try it.. No strike! Crap!

There is a serious amount of fasteners holding these fixtures together! Only two 8-32 screws holding the upper wiring box to it’s architectural mounting bracket... 18x 10-24 other screws for the rest of it. Given I changed all viable 10-24 screws to longer ones so as to thru bolt with some form thread deforming locking nuts - those screws were not easy to get off in dissembling the first fixture. Neither my assistant’s fixture or mine worked in testing... Given all stainless steel hardware - the screw & nut were scrap once removed. Normally if doing say a top lock nut with a screw, the top lock nut is stainless steel, the screw either a zinc plated steel, or green plated grounding screw. The nut against the softer material is re-usable, the rest is scrap. Thread deforming nuts tear up threads. In the case of Stainless nuts with Stainless screws - harder to install and both scrap after use. Had to open up the first fixture and see how we mis-wired it in not working.

Pulled in the head of the electronics dpt. in not seeing anything wrong - he deals with arc lights more than I do - even understands the voodoo magic about how they work. He traced the wiring, measured the amperage... everything looks correct! He took some notes on the parts and fixture model and did some research... everything should be working.

He would continue to do some research on the various parts making up the ballast, but in the mean time... here the companies’s help line. I called... left a message on voice mail... Some help in no call back at all today. Suspect I know why!

This is bad - show is leaving in like six hours and of seven fixtures, we have not even started two of them. These fixtures came with a factory lamp, we tried a Sylvania version of it.. Still no go.

Theory next agreed on... perhaps these fixtures had the tap on the transformer mis-labeled / attached to their terminals - this after confirming the dual neutral wire taps off the transformer were bonded together. 5x taps for voltage per transformer, and given we were tapping at 120v, the risk of damaging the transformer by powering it up from another 208v, 277v etc. tap was limited - or might work. While I tested all the various voltage taps to the ballast, my assistant was readying to power it up at 208v. While I tested a second time with the different brand of lamp... Stop wiring this ballast up as if we were going to send it on a show!!! Get it wired for 208v and use factory wiring until we make it work! (Sorry, really smart assistant but some times...)

Fixture came pre-wired for 277VAC, but it would take hours to tap into either the overhead fluorescent light or exit light power for testing the fixture as wired for power from the factory.

My assistant noted to me that his lamp wasn’t really screwing in properly. Funny, mine seemed to screw in properly. Tried it... nope, it wasn’t really seating all the way. Looked at the lamp socket, noted a part of the lamp base C-shaped ceramic shield around the center contact for insulating it from the outer shell. Noted... Hmm, that’s a little small in size and raised above the center contact, let’s lift up that center contact so...

Wait a minute, stop working on the 208v conversion, let me try this on the 120v with me lifting the center contact. Lifting it enough that the center contact almost loost it’s compression spring under it struck the arc!!! Try this method on the first done fixture... works!!! CRAP! Try the Sylvania lamp in the fixture... it also works!

Debate as per management and "worker" problem. We now know how to fix the problem - just bend the center lamp socket contact so it will touch the pin of the lamp cener pin. Not great surface area but will work and get this problem back on schedule, or pull in more labor and replace the lamp socket. Was a big question for a moment before I had to choose changing all lamp sockets in doing it properly as opposed to some upper manager yelling at me for the lights not ready to ship before explination. If I replaced all lamp sockets - it would be a lot of extra work - a lot of extra work. Explination to managers can involve them too mad to listen instead of yell or fire you thus forcing the easier solution where bad managers, or in this case secure in job and would do it right as opposed to bending out the center contact for less surface area, and possibly that now loose contact spring potentially flying free and shorting. Job done correct over pissing off someone. All on me and why I'm there.l

Great you figured it out!!! from the head of the Electronics Dpt. impressed with my troubleshooting. That ceramic ring on the lamp socket so as to insulate the center contact from the shell was preventing the button of the E-39 based 400w lamp socket of the lamp - they provided with same brand in slightly larger dia. from contacting the center contact. Didn’t matter if factory or retail lamp also in not contacting. Were it a different brand of lamp than either - this might have been fine in smaller lamp button contacts. But not now.

I theorized the High Pressure Sodium lamps perhaps had a smaller button, and someone perhaps ran out of the Metal Halide working lamp sockets... but nope... same size button. Someone at the factory in changing lamp sockets from what was tested and spec. really really screwed up, and or the quality assurance people for a change didn’t test the lamp socket that don’t work with even the lamps they supply. Err.. Voice mail... I figured out why you might have so many calls about a fixture assembled last year not working - you have a huge recall problem!

Luckily I had enough pulse rated Leviton lamp sockets in stock with spares for the show! They were a different mounting type but we worked that out and even figured out that you didn’t have to completely dissemble the fixture to change the lamp socket. Faster but not easier in getting to the screws attaching lamp socket frame to housing. Much more difficult, but didn’t have to remove 18x screws and replace all - just 6x much more difficult to get to for those fixtures mostly done or too far in the works. Pull the lamp socket wiring out thru the ballast shell, high temp. splice crimp, shove the wiring back in and re-bolt. Much more difficult to get access to the mounting screws but quicker. Five Man/hours added to building seven lighting fixtures due to this factory error.

Luckily he was understanding about the problem in general. This after me starting the day by calling him an Idiot! Used the term this morning to him in reinforcing that no you cannot install a metal halide lamp into a high pressure sodium vapor fixture. Got told first thing in the morning how my assistant and he were noting how the factory metal halide lamps fit into the HPS fixtures, but the Sylvania ones did not... What!!! Idiot! My prime assistant is very smart, and on many things smarter than I am. But at times.... Why were you letting them install a metal halide lamp into a HPS fixture? Only 15 more years to turn him into me. The same amount to also properly train crew chiefs. This one now trained on concepts of the two different lights, how both are constructed, how to gel one as needed, safety concerns on the other, how to change the lamp bases, what screws to try not to remove - why and or what needs replacement. How many wraps of tape etc. Training for maintaining their light so they don’t have to make it up on the fly. Long day to just retrofit seven fixtures to be road ready.
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Tour cancelled! Not public/shop knowledge about this especially to my prime assistant. I was only told off the cuff and not by Management, and after not public knowledge. For me, once something leaves my work area, I'm not emotially attached to it. Fine with it uniless it comes back and I have to find time in doing something with the gear. All this effort... 20 years of experience in making stuff at times for shows in a rush, at other times, stuff cut from a show. Got it out my door in best I could make it and that is the extent of my concern.
I mentioned this to you via PM but I thought I'd share the theory here for the sake of the forum.

From what I remember about working on high-bay metal halide lighting, there are two lamp-and-socket combinations available: enclosed-only and open-rated. Enclosed fixtures, designed to contain the lamp in the event of a non-passive failure, are intended for areas where such a failure could result in a hazardous condition. I'm thinking maybe areas with a lot of people or warehouses that store combustible goods. I'd think that would cover just about anywhere high-bays would be installed, but I digress...

Anyway, I believe you would find the sockets in either white or pink. One means enclosed only, and the other means open-rated. I forget which is which. But similar to the 575w Source Four lamp cap, one type of socket assembly is designed to be just different enough to not easily accept the other's lamp, preventing the layperson from putting an "enclosed-only" lamp in to a non-lensed fixture.

I could be wrong on all this, but I'm wondering if maybe the supplier sent the wrong type of lamps. If memory serves, the open-rated lamps contain a reinforced glass/quartz shroud around the arc capsule, while "enclosed-only" lamps lack such a feature. I'm guessing that cart came after the horse because I would swear I've seen non-reinforced lamps operating in open fixtures (my scene shop, for example). I'll bet it was a code update that arrived long after MH had been established.
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Very interesting question, and Wifie did present the problem of these open faced fixtures with no safety screen. Crew chief said this was not a problem in bringing that up - lights not in the area of the talent. As for lamps bought, normal type Sylvania & the factory provided ones - not open faced ordered or provided as per specilized - though I have heard of open face fixture lamps, not thought of this. Mistake on my part in not remembering such a detail. Open faced High Bay in the shop and was not high bay open face specific ever bought for them in working. In putting the lamps on rush order - I also didn't see what fixture was being bought... Getting lamps and fixtures on time was a rush, I did the lamps and was thankful someone found the fixtures in me striking out.

Wish I had thought of this. Possibly the high bay light open faced fixture might have a slightly different lamp socket in safety. Won't work with a normal lamp! Brilliant. Problem with that is the factory shipped lamps - wrong lamps? in not working. And the shop high bay's with open faced before converting to LED also didn't have that designated lamp base in working fine with normal lamps.

Still yet to get a call back from the factory, but something to inquire about. Thanks! Otherwise Mark from Osram? is there a different lamp socket design and lamp base design for open faced HMI High Bay's? He would know or be able to find out thru insitutional and or contacts knowledge. This even if no longer linked to the other company Sylvania.
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I'm afraid I am no help at all on this one, Ship. E39 Metal Halide for High Bays or other General Lighting lamps aren't part of my portfolio or experience. Our group is entirely specialty and doesn't have any screwbase lamp designs. I don't even know who to send you to at LEDVANCE (our former General Lighting group) anymore to ask them. :-(
Checked my notes on the lamp type - none noting a open/closed fixture lamp difference in this version and especially lamp socket/base difference. (Good idea.) Beyond that, why would the same maker of the High Bay in installing the lamp socket, also provide a lamp with their own name on that provided lamp with the fixture... doesn't work with it. There is in looking at it literally a 3/16" difference between the height of the center pin and that ceramic ring. Would take photos' and did, and sent them to me by email... but I have a Droid phone... and they "Upgraded" so email no longer works on the phone. Been over a week now, suppose I should switch to the second email address for it. Droided! Suppose I should re-call the manufacturer so as to annoy them in getting paid back at least the cost of the replacement sockets. Or find the venor that sold the fixtures and or do that.

Was board at the start of the day, but than I got in this Pelican road case today for a tour leaving but the end of the week. Not a tool box - it was a controller for two 20' turntables. You just need to change the plugs on it from L14-20 to something that works three phase. (L15-20 perhaps...) I don't want to touch this thing.... Ran thru a multitude code vilotions in it - a good list to the crew chief. Onto busy in building a new controller. Not one but two given tour notes of other reasons for two seperate controllers for two 20' lifts. That and obsolete the replacement controller I'm working on for a few hundred dollars, the electronics dpt. in the shop is also working on a different version to address further issues. Further approval, these I am working on will get the system running and be spares as requested.

Tour cancelled on the above HMI... will save the fixtures perhaps a few years should the tour come up again, or the designer want them. But as with a lot of gear in purges... will if not used in a few years get scrapped. Every week something new.
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