200w or 250w?

[Varakan Ten Tipprapa]

Hello,

I plan to stock enlarger lamp. I just checked on my LPL 4500. It's using 200w 82V.
What if I use same voltage , but put more for 250w for gain more power of enlarger light beam with shorter time in bigger size print.. Can I do that?.. Both lamp are totally same size.

The light tube 250w 82V using in LPL XLG. I just know the difference between LPL 4500 and XLG are column length and extension for the headlamp... The light-house should be the same.. So that I can put more Watt on the lamp..Isn't it?

http://www.adorama.com/LMEVW.html

http://www.adorama.com/LMEYA.html

Please anyone who has experience, consulting me some

Thank you,
Ten.

[Eric Biggerstaff]

I use the 4500 as well.

Doesn't it have a larger fan as well to pull away the heat?

I would only be concerned about heat and possible internal problems it may create.

[Ron Marshall]

250 watt is 25% more light output, assuming equal efficiency, so there should not be much of a reduction in exposure time.

[Eric Biggerstaff]

Sorry, doesn't the 4550 have a larger cooling fan is what I meant to say.

[Oren Grad]

In their parts list, OmegaSatter specifies the 250 watt lamp as being for the 4550 only.

I'll be heading downstairs to my darkroom a bit later on - while I'm down there I'll check the documentation for my 4500 and see whether there's a specific warning against using the 250 watt lamp.

[Armin Seeholzer]

Hi Varakan

I have the 4551 which came originaly with a 200 watt bulb but using it since 2 years with a 250 watt bulb, bevor I did it I asked a 2 different elecronic guys one with a very high degree in it and the other one with much practically expierience and booth told me it should not be a problem at all.
So it worked since 2 years for me but this is at 230 volt here in Switzerland not a 110 volt so you should maybe also ask some persons in your aera with electro know how!
Good luck, Armin

[Varakan Ten Tipprapa]

Thank you for you guys opinions,

Ron, now I use 4x5 to 11"x14" paper at 70cm distant at f11 to f8. If I change to 250w, I think I can go one steep more to f16-11, should be a better result for middle on lens exposure number

Oren, as you said, I can just change to 250w shouldn't be any problem..

John, since you've been using for two years with 250w. It should be fine with my as well for the Voltage is not an issue... I think..

BTW , I checked more I found "360w82V" <--- That was absolutely will burn heatsink..ahha

Cheers,

Varakan

[Roger Scott]

I would not blindly install a 250W globe. Although the voltage is the same it will draw 25% more current which may overload wiring, connectors and/or the transformer. Power dissipation is proportional to the square of the current. An enlarger head designed for a 200W globe may not have adequate cooling for a 250W globe. Thermal dissipation is measured in degrees per Watt so a 25% increase in power rating will require 50% more efficient cooling. You need to confirm that both your enlarger head and power supply have been designed to handle a 250W globe.

Regards,

[Ron Marshall]

Ten, I forgot to ask, does it have a switch on the power supply to run on 220v, or will you use a transformer?

[Oren Grad]

Nothing about it in my 4500 manual, alas. If you're in the US, why not just call OmegaSatter to be sure?

[Donald Miller]

The 4550 VCCE XLG that I have does have the 250 watt lamp...it is not recommended to switch wattages from the lower wattage to the higher wattage lamp according to the mfg. The problem is one of heat build up from what I understand.

[J D Clark]

I have to admit I have used a 250w lamp in the 4500 II that I have -- it occurred to me that the brighter lamp would result in shorter exposure times, so the heat buildup with be corresponding less. So, I charted the time/temperature pairs for both lamps up to about five minutes, and found that the 250w lamp was indeed hotter, but not outrageously so, and about to the same temperature if you take into account the shorter exposure time.

So, I ended up using the 250w in my 4500 -- and tried to make sure that I didn't spend too much time framing and focussing.

As far as I can tell, the power supplies for a 4500 and 4550 are the same. Of course, this is against the manufacturer's recommendations.

Finally, I don't know how the light output per wattage works, but the 250w lamp *did* have more than 25% increased output, it was more like about a stop increase. Perhaps it was an old 200 versus a new 250, but I was pleasantly surprised (but didn't chart the actual difference).

John Clark
www.JohnDClark.com (http://www.johndclark.com)