Halogen lamp for Omega Super Chromega D Dichroic

[jack_hui]

Hi all,


I just received my first 4x5 enlarger D2 with Super Chromega D Dichroic color head today. I powered it up and works fine. However, when I check the halogen lamp, I found that the one installed is "120V 250W", which is different from what it should be ... 24V 250W.

I don't have any voltmeter with me at this moment, can't check what is the supplied voltage of the lamp.

Anyone know what went wrong? Or what should be the correct lamp to purchase?

Thanks
Jack

[vinny]

I bought mine from freestyle. If the lamp works, and your exposures are fine, I wouldn't change it. It may just be a labeling issue since your plugged into 120V ac.

[jack_hui]

I am new to Omega enlarger, not sure it is an issue or not.
The seller forgot to send me the power supply that come with the color head, so I simply plugged into 120AV. My question is, there are three electrical components, a cooling fan (labelled 120VAC), a panel lamp ( labelled 120VAC) and halogen lamp (labelled 120VAC, but according to manual, it should run 24V), does the color head have a transformer inside to convert 120VAV to 24V? it seems to me that there are nothing like transformer or converter can be installed in it.

[ic-racer]

Your head has been converted to 120 vac. The wiring to the head would have needed to be upgraded from 24 v to 120v and the socket changed. The 24 v and 120 v lamps look similar but have different pins.

[SpeedGraphicMan]

Hello,

I have a similar head, and had a similar problem! No power supply!

No, the head does not have a transformer inside! But 24volt transformers are easy to find at a reasonable cost!

Check out...
http://www.jollinger.com/photo/cam-coll/manuals/enlargers/omega/Super_ChromegaD_Lamphouse%20(orig).pdf

And...

http://www.jollinger.com/photo/cam-coll/manuals/enlargers/omega/Super%20Chromega%20D%20Lamphouse%20Dichroic.pdf

Which head do you have?

[jack_hui]

Hi all,

Thanks for the information.

I have double checked and believed that my color head has been converted to use 120VAC, with only one socket. i.e. I can't turn on the panel lamp and exhaust fan separately!!! Panel lamp, fan and halogen lamp are all on and off at the same time ....... too bad, what a stupid modification.

[ic-racer]

As you have found out, to do that 120V modification correctly they should have split the power from the lamp and fan, just like the original power supply.

If you can locate a power supply, it should not be too difficult to change it back. The plug that goes from the head to the power supply can be hard to find, I think Mouser had them http://www.mouser.com/ProductDetail/Molex/38541-5406/?qs=sGAEpiMZZMviIjlYfy6lqid%252b4NDoWAbSeK9EN4wnh8U%3d (link to Molex 5400 6P plug). A new lamp socket is around $10.

From what I recall the plug from the head to power supply is wired as follows:

Green = Ground
Black = Hot 120 VAC
Red = Hot 24VAC
White = Common

Note: the Chromega heads I worked on have a 4 wire cord, even though the Molex plug is a 6 pole plug.