Super Chromega II lamp problem

[Wayne]

I finally got my darkroom fully working again for the first time in 2 years, set aside the weekend to print, and now my projection lamp wont work. The old one was blown, I could see the broken element, but the brand news ones arent working either (and they arent blown). I have given the wiring a look and everything looks fine. I've cleaned the 2 pin terminals for the bulb, and still nothing.The fan works, and the display bulb works. I have a feeling its something really stupid, like when I couldnt figure out how to remove the bulb a few days ago....any ideas?? in the meantime I guess I'll have to see if I can get the old 45MX to turn over...

 

[pelerin]

I finally got my darkroom fully working again for the first time in 2 years, set aside the weekend to print, and now my projection lamp wont work. The old one was blown, I could see the broken element, but the brand news ones arent working either (and they arent blown). I have given the wiring a look and everything looks fine. I've cleaned the 2 pin terminals for the bulb, and still nothing.The fan works, and the display bulb works. I have a feeling its something really stupid, like when I couldnt figure out how to remove the bulb a few days ago....any ideas?? in the meantime I guess I'll have to see if I can get the old 45MX to turn over...

Wayne,
Are you using a power supply or a chromegatrol to run the lamp head? If the answer is power supply... do you have the "deadman loop" where the timer goes hooked up properly? A good bulb inserted partway in the lamp socket should show AC voltage across the lamp pins. Insert the lamp fully, pull it back out a bit and, taking care not to short across the pins or to the chassis, test for voltage. If you have no voltage you could have: 1) a lamp socket problem (they are supposed to be changed at regular intervals), a connection problem where the lamp socket is tied to the power imput, or a power supply problem (unfortunately the fan and panel lamp are not indicators that the lamp circuit is working, they are a separate circuit). I have found Dave Smith (Smith Electromechanical, located in LA) to be a helpful resource with dead color heads.

 

[Imke]

Hey Wayne, sounds like you've already checked the crimp connections on the little connector board underneath the lamp compartment? That was my problem a while ago. Might want to try replacing the socket.
http://www.classic-enlargers.com/
Good luck!
Imke

 

[Wayne]

Well,this is what we've got. I'm electrically challenged, so bear that in mind. I may sound like I know what I'm doing with a multitester but I really dont.

I am 99% certain the head is hooked up right because I havent changed it since I last used it 4 years or more ago. The power supply/stabilizer is plugged into the wall and the timer is plugged into the only place it can be plugged on the back of the power supply. I have the timer on focus when I'm testing. I used the timer last night on my Beseler and it worked fine.

I got no sign of voltage testing the partially inserted bulb as suggested, power on. I disconnected the socket completely, and got no resistance in the socket-bulb combo, and none in the wires (formerly) leading to it either. I got no voltage from the latter either. I double-checked each wire back to the spade connectors and both are good with no resistance. I'm stumped. Good thing I have the Beseler

 

[Wayne]

Got it. As I suspected, it was something stupid. I didnt have the deadman loop hooked up properly. Thanks for the help, but as the saying goes, you cant fix stupid!

 

[pelerin]

Got it. As I suspected, it was something stupid. I didnt have the deadman loop hooked up properly. Thanks for the help, but as the saying goes, you cant fix stupid!

I can assure you that you are not the first person tripped up by design of this power supply. Many second hand units "lose" the all important short extension cord for coupling the timer back to the PS in the process of moving to a new owner. ...glad your machine is up and running, hope you get some good prints.
Celac.

 

[Wayne]

I didnt remember doing anything with the enlarger since I last used it, but I must have stolen that short extension cord for some other purpose. Oh well, its up and running now but no masterpieces tonight. Tomorrow!