Enlarger conversion from 100watt/12V to 250 watt/24V???

[naaldvoerder]

I have a Dunco 100watt/12V halogen light enlarger, but I find i have not enough output for my taste. Did you ever convert a 100V enlarger without fan to a 250 volt enlarger (with fan)????? Did it work?


Thanks Jaap Jan

 

[Chan Tran]

A fan would help. Quartz halogen lights are available in many different wattage in the same size bulb so the conversion isn't too difficult. Make sure you rewire the enlarger with sufficient size for the higher wattage. My enlarger has 2 200W bulb and it still doesn't have enough light output.

 

[Steve Smith]

Make sure you rewire the enlarger with sufficient size for the higher wattage.

Actually, if it's currently a 12 volt/100 watt enlarger then it has wiring suitable for at least 9 amps.

Wiring is rated for current flow rather than wattage.

At 9 amps on 250 volts, the wiring would be fine for a bulb up to 2250 watts!

What you do need to check though is that all terminal blocks, etc, are suitable for the higher voltage.

Did you ever convert a 100V enlarger without fan to a 250 volt enlarger (with fan)????? Did it work?

Have you mixed up watts and volts? Initially you said 100 watt 12 volt but then asked if anyone has converted a 100 volt enlarger to 250 volt.

If you meant 100 watt to 250 watt staying at 12 volt then you will definitely need to upgrade the wiring and the power supply.


Steve.

 

[ic-racer]

Interesting concept. As Steve pointed out, you will be able to go to a higher wattage bulb on the same gage wiring. However, I suspect if the enlarger were originally designed for a 100W bulb, some other component of the system could fail with the higher wattage bulb.

Are you lith printing?

 

[naaldvoerder]

I sorry for the mix up. I would like to use the 250 watt halogen lights in my enlarger. Apperenly they are 24V, so i figure i need a 24volt trafo, and some more cooling....

Thanks Jaap Jan

 

[ath]

The Dunco is widely considered as an enlarger with very bright light. Are you sure everything works as it should?
Most people ask how to reduce the output from the Dunco.

 

[Steve Smith]

For the wiring, some simple maths. Power = Current x Voltage

Re-arrange that to Current = Power / Voltage

For the 100w/12v: bulb Current = 100/12 = 8.33A

For a 250w/24v bulb: Current = 250/24 = 10.42A

The difference is not enough to worry about as the original wiring would have been specified well over the original 8.33 amps. Probably closer to 16.

However, you will need to find a 24 volt power supply rated for at least 10 amps and you will probably need to do something about the extra heat which will be 2.5 times that of the 100w bulb. Obviously you have thought about that by asking about a fan.



Steve.

 

[naaldvoerder]

The Dunco is widely considered as an enlarger with very bright light. Are you sure everything works as it should?
Most people ask how to reduce the output from the Dunco.

Andreas, everything is as it should be, except for the 6x7 lightbox I also use for 35mm. I use a splitgrade. Making a 30 x 40 on Forte Polywarmtone gives my usealy 40-60 seconds on 4.0 on ApoRodagon. Lithprinting and/or burning can add up.

Jaap Jan

 

[Chan Tran]

100W/12V originally converted to 200-250W/24V then the wiring should be sufficient and doesn't need to be rated for higher voltage either. If you can find a 10-15A 24VDC regulated power supply somewhere cheap then it would be better than just a transformer. If installing a fan inside the head seems difficult you may want to use an external blower and hose.

 

[domaz]

You can't use a transformer for DC it has to be a AC-DC or DC-DC power supply. Good luck finding a 10A-15A 24DC supply for cheap. All electronics has a 6.5A 24V not quite enough. BG Micro has a 48V 5A model though... it has the equivalent watts but twice the volts.

 

[Chan Tran]

The transformer would give AC but the light bulb doesn't care AC or DC. With the transformer you won't have the voltage regulation.

 

[Bob-D659]

Maybe a 35mm lightbox would be better. I have a Durst 1000 with the CLS 450 colour head, it came with a 80 watt 30 volt bulb. I replaced that with the stock bulb, 24v 250 watt, and had exposures of 6 seconds at f22 which was a pain with the 35mm light box. I put the used 80 watt one back in, now 10 sec at f8 is more liveable when printing colour 8x10s.

 

[ic-racer]

Good luck finding a 10A-15A 24DC supply for cheap.

Agree with that.

You could use just a transformer, (you don't NEED a regulated power supply). However I see Hammond makes two 120v to 24v transformers rated around 10 amps, but the cheapest one is $75 USD the other is over $100 USD. Again, thats just for a bare transformer. You still would need to make a box for it etc.