Led upgrade for opaque projector?

T

TattooGabby

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So I have just received a Braun Paxiscope 650 and the bulb didn't make the delivery. Turned it on and the bulb died.

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This is the same as the Artograph MC 250 essentially. Rather this is the 220 volt original that was later sold in the states as the MC 250. The bulb it uses is an OSRAM 64540 with a GX6.35 socket.

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Now as knowledgeable as that might sound, the one thing I don't know is wether or not this bulb uses a special ballast or not. If it doesn't then I could take an LED with the same socket designed for AC power and swap it out. Sounds simple enough right? However the lumens may be an issue as the original is something crazy like 2000 lumens. I would prefer to do this without rewiring the unit and I assume I will just buy a power hungry original bulb if it isn't possible.

So has anyone used this style projector? Has anyone attempted a more efficient bulb replacement? Is there a high voltage ballast lurking in there? Anyone?

Thanks in advance!
 
Only thing I'd worry about m8 is the LED will get way to much power..Having a quick looksie into em can't say it can't be done, but it seems like about a 650 watt globe, so pends I suppose on the LED power needs but cant see a LED needing quite that much so yer wld prob take some Frankensteining, if worse comes to worse, whack a candle in it LOL, but to be safe I'd order a few more globes and stick to its standard replacements...Maybe a diming switch though to cap the power going in but wld hate to see it catch on fire..Maybe give the manufacturers a quick email and see what they say..Good luck.
 
Well that was pretty much where my question was directed. Maybe I should clarify.

Wattage is the sum of amperage x volts. So 650 watts is roughly 230 volts at 3 Amps ( 2.7 ish ).

So this very well could be straight mains power with no ballast.

However I know that Halogen bulbs are not my field of know how ( dc power is ) although I know some led bulbs in the G4 sockets have an inverter built in to convert mains power to DC however I haven't found a GX6.35 variant.

I am pretty certain I will have to get a DC inverter that is regulated to 20v at 1 amp and use a flat panel DC projector bulb. That option would run me around 30€ and meet the 2000 lumen mark. Only draw back would be that I will have to modify the unit from stock. I always like to be able to revert back to stock.

Guess all that is left is for me to crack it open and see what I have to work with.
 
Sounds like your forte, power stuff certainly ain't mine LOL, when its all said and done most globes as ya likely more aware than me is just x amount of power in-heat a filement-x amount out, couldnt see why if LED's, halogen or normal light globes all pretty much run of my same power in, no doubt its just the ballasts or transformer or whatever else in em controls stuff is the right match, cant see why it wouldnt work besides fit..Sounds like an interesting project though, one I'd likely kill myself on by cutting the red wire LOL..best of luck on it :)
 
I'll stick to my old school light bulb and mirror projector lol. Don't have the cash to modify led or I'd go all out on it.
 
I ordered a bulb for it ( the original spec halogen ) then I will try and measure the output and see what I can match it with or improve it led wise.
 
Why don't you hook up the probes of a mutli meter to the sockets where the bulbs goes in and see how many volts are produced. Most LED's and halogens are low voltage DC current and require a transformer.
 
I know this is an old but for the record you can put any bulb that does not require switch gear into any socket provided it is the same or less power. A 650W halogen lamp draws its power from the mains only. You could effectivly put a 1W LED into the socket and be 100% safe (even though you wouldn't do that)
 
I rather like the idea of switching to an LED, but as you pointed out running it from AC may require a few additional components.
If simplicity is your goal, I dont see why you can't do something similar to the image I have attached to this post. You might double check my math, but I think it would be the easiest way to replace your bulb with an LED without the need for a complex constant current driver circuit (which may be desirable if you don't wish to have two LEDs, as each one would be operating at 25hz, which has some flicker, but since they work on opposite ends of the AC signal, they should blend together to make it about the same as a 50hz light).

If you want only one LED, you could go with either a constant current driver circuit, or if you want to include dimming capability, a PWM circuit might be more advantageous.
 

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