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LED interchangeability

Keeper of the Keys

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Over the past few years we have seen the rise of LEDs as the new light sources, and though it will probably still be a few years before they really take over (if they take over completely) I was wondering about a few things.


One of the things that I am a bit apprehensive about is the option to change the chips in the fixtures, of course 20k-50k hours is a huge amount, but it still seems crazy that at the end when the LED chips die you may have to chuck the whole fixture instead of just replacing the "bulb".


It could be that I am wrong and that it is possible to change the chip, it's just one of those features no one really mentions and the products I have seen didn't necessarily look like it was easy to replace.


Another thing I think is a pity is that at least at the moment every manufacturer is making their own LED sources, with their own standards etc. (though some/a lot may be based on the technology of other companies like Philips color kinetics being re-branded/marketed by other companies in America), so we don't get the same market you have now for your conventional fixtures (I really mean non-LED here) with several parties working just on making more efficient bulbs that have a standard connector and therefor can go into fixtures from all brands while said brands work on the fixture design around the bulbs...


I am very curious what the rest of you think about these issues and what other issues but also good things you see in the current movements in our field.


Edit: spelling and brand names

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Replacing leds is possible most of the time,

provided that parts are available,

substitutes can be found for most, if you are determined.

even surface mount leds can be changed,

if you have good eyes and a good soldering iron.

Is it easy?

generally not, its fiddly and easily damaged if you are not carefull.

But it is possible if you are determined.

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Is it not the way with modern electronics to chuck it when it's broken rather than repair? The place where I grew up had an old tv/radio repair shop in it's row of shops but with the modern trend of when it breaks buy new, they sadly went out of business. Even working in the electronics industry if my tv broke would I take it apart and try and repair it, probably not. It's just easier to get another one..


With something that has such a long life, will there still be the same kind of LED still be available come the time to replace it? The technology is changing so rapidly that I suspect it would be difficult for manufacturers to keep a stock of parts to service all of their LED fixtures for decades to come, but it would be interesting to hear from the companies that manufacture the higher end LED fixtures on this.

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Varilite VLX's are designed with replacement/upgrade in mind.


But IMO unless you have a fault or run these things 24/7 in full white then chances are the lamp will probably outlive its housing and electronics. Even if it didn't surely technology will have moved on so far by then that you would almost certainly want to replace it anyway?

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You could compare LED Light fixtures to Laptop/notebook computers.


What do you do when it packs up after a few years? Throw it away and buy a new one. Basically every month a different manufacturer is bringing out a new Laptop with slightly better graphics or a faster processor that makes all the models that are only a few months old redundant.


Whats the point of trying to keep it when there's a much better alternative out there?


But on the other hand Scanners (e.g. HES's Technobeam) have still survived after 30 odd years of being in existence. Why do people keep on fixing them up and keeping them in large numbers in their hire stock? Because there is no alternative, and if there was a modern alternative (again take the Technobeam for example) I'm pretty sure people would snap them up mainly for the fact it would be most likely cheaper in the first place to buy and maintain than a 250w moving head and for its lightning quick pans and tilts.

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Agree, replacing LEDs is posible but most unlikely to be worthwhile.

If only a few have failed, then performance may still be acceptable, if many have failed then it is probably time for a new lantern.

They should last several years of heavy use, or up to a century of once a week use.


One could design the complete LED PCB to be replaceable, but this is a large part of the cost of the lantern, so there may be little point.


Somtimes the driver electronics fail, and this may destroy the LEDs.

Repair would be rather pointless in that situation, since all that is being re-used a cheap pressed steel case.

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25K hours is almost 3 years of 24/7 operation, which is pretty good but a lot les than the 100K hours that is oft quoted.


Drivers are in a way developing standards, Lumileds made then 350mA / 1W a standard by sheer weight of marketing.


US makers have little choice but to pay Phillips one way or the other, Phillips own all the old CK Patent portfolio and keep adding to it.


Can see some sort of aftermarket developing for `pattern` LED panels in the future.

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Though I also see the tendency to "disposable electronics" they usually tend to be a lot cheaper, I can imagine that a small venue that makes an investment of more than 2000 USD per fixture would expect there to be more use out of the fixture than just the life of the bulb even if that life is 3-5 years. Look at the current inventories of venues (not rental houses) they can still happily carry ellipsodals/profiles/fresels/pcs/pars/you name your conventional that are more that 10 years old and have good use for them.

The initial investment in most of those fixtures is also a lot lower and their life at least on the outside seems to be a lot longer.


Of course their electricity bill over their lifetime will be a lot higher than that of an equivalent LED fixture meybe even high enough to justify buying a LED fixture instead but even then it's definatly harder to show management that fixture X which will have to be replaced faster and has a much higher initial cost is cheaper in the long run....

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In any normal theatre application the lanterns should last a great deal longer than "3 to 5 years" which assumes continous or near continous operation.

25,000 is indeed about 3 years of 24/7 operation, or more realisticly about 12/18 years of operation at 4 or 6 hours a day.


The cost of replacement after this time will be trivial compared to the saving in electricity and replacement lamps.

Consider an LED fixture that cost $2,000 and lasts 25,000 hours.

The saving in electricity could reasonably be 1KW, over 25,000 hours at 20 cents a KWH that is $5,000.

The halogen equivalent lantern would have used at least 50 replacement lamps at say $20 each over that time, thats another $1,000 saved. Savings in gel, and lamp replacement labour are not easy to determine but could be substantial.


Therefore the $2,000 fixture has saved about $6,000 over its lifetime, or a gain after the initial cost of about $4,000.

Remember that the replacement will probably be cheaper than $2,000.

Electricity is liable to get more expensive.


In a new install the capital cost of LED lanterns is effectively zero since the higher cost of the lanterns is offset by the much reduced costs of substations, switchgear, cableing, dimmers, air conditioning, and the space not occupied by this equipment.

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A couple of other things I want to mention:


Different batches of coloured LED's differ in tone - sometimes quite significantly. Manufacturers generally buy a bulk batch of LED's - so manufacturer replacement LED modules is possible, certainly... but off the shelf LED lamps for fixtures could end up with you owning a mess of different coloured fixtures. The LED panel replacement will be more like replacing a colour wheel or something of the sort, done on a bench in a workshop by a qualified technician. But it will be like any fixture spare... There is a good chance that when the fixture is superseded they will stop getting spares made for that fixture.


Another point of note: Led's go from Off->Bright in next to no time. So where an LED fixture is replacing a discharge source, 25,000 hours is not the same as 25 x 1,000hr lamps in a discharge fixture. Why? Because you don't "strike" the LED's (which cuts a couple of hours off the lamp life each time) and the lamp is only on when it is emitting light (instead of sitting behind a dowser). 25,000 hours is also the half-life. The Cantata that the theatre has had for 9 years is probably fairly dim, probably nowhere near as bright as it first was. At 25,000 hours, your LED fixture will be at half intensity. Most people will still squeeze more hours out of that fixture. It is not like a discharge source which after about 1300 hours is more like a ticking time bomb waiting to blow just before it is needed. The light will not hit 25,000 hours and just stop working.


Finally, the very fact that the LED's only draw power whilst emitting light means that your power consumption (when compared to a similar sized rig) is next to nothing during a blackout. 45W per fixture to keep the DMX receiver and the control boards running basically. So you have a more efficient light source when on, but you also have a fixture that burns power only when needed.

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Different batches of coloured LED's differ in tone - sometimes quite significantly. Manufacturers generally buy a bulk batch of LED's - so manufacturer replacement LED modules is possible, certainly... but off the shelf LED lamps for fixtures could end up with you owning a mess of different coloured fixtures.


This is only true for cheap far-eastern fixtures. For pro-quality stuff, LED manufacturers sort their LEDs into different "bins" of colour/brightness/forward voltage, so that fixture manufacturers can always buy matching LEDs. You can see the binning if you go, for example, to the Cree or Luxeon Rebel websites.

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