Rewire print head?

Discussion in 'Contact Printing' started by JohnRichard, Apr 28, 2008.

  1. JohnRichard

    JohnRichard Member

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    Is there a "good" way to rewire the plug on an Omega C colour head? Its the one that plugs into the ballanced power supply, 4 prongs and 1 round thingie...

    anyone know? It cant be that hard... its a light and fan... most likely AC.

    I should say is there a way to reprogram the plug to accept a standard darkroom 'big clock' timer?

    JRY
     
  2. Mike Wilde

    Mike Wilde Member

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    bulb voltage - wactch out

    I am pretty sure that the bulb is definitely not 120V. Line voltage would be poof pretty fast. I think that it is something like 24v ac or something. Yes, 120V for the bulb on the head that lights the filter dial, and the fan. Not for the halogen light.
     
  3. domaz

    domaz Member

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    As Mike says you could do it but you might destroy it because of the different voltages. That being said you could use a multimeter to figure out which voltage is high when the light is on in the plug. Then use a relay to control that wire via the timer. Do this by hooking the trigger voltage terminals on the relay up to your big clock timer and put the relay main terminals in between the plug and it's source (power supply on enlarger?)
    Like this:

    =----R----​
    |​
    -----C--->​

    = (enlarger plug)
    R - relay
    | - trigger pin on relay (connected to output of clock)
    C- clock output
    > main line voltage for clock

    Maybe I'm totally off the mark here but it seems like this would work. You would just need an AC trigger voltage relay like this one.
     
  4. fschifano

    fschifano Member

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    Four spade prongs and one round in the center? That sounds like the Chromega II lightsoruce and power supply. If that's true, I can tell you with certainty that the bulb is 250 watts at 24 volts. Do not attempt to feed mains current into that thing or you'll blow it for sure. I'm not sure what the fan takes, but the voltage and current requirements should be printed on the fan itself. Do not attempt to run the bulb without the fan running. It will live a short life. Ask me how I know this. The fan should start as soon as you energize the power supply and remain on until the power supply is switched off.