Durst TRA 305N

Discussion in 'Darkroom Equipment' started by Bram M, Feb 15, 2010.

  1. Bram M

    Bram M Member

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    Hello,

    A technical question:
    I have a durst M605 enlarger with a durst TRA 305N transformer. It came with a 12V timer connected between the trafo and the enlarger.

    I really don't like this timer, and would like to use another one, one that operates at 240V. Would it be OK to I put this timer between the mains and the trafo, so that the trafo also switches on and off when I expose?

    Many thanks,
    Bram
     
  2. mpirie

    mpirie Subscriber

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    When you consider that all an enlarger timer is is a method of interrupting the flow of electricity to the light source for a specific and repeatable time, then it theoretically makes no difference whether it's on the 12v (lamp) of 240v (mains) side.

    Using it on the mains side has some safety aspects to it as well as putting additional strain on the transformer. I don't think transformers like the constant surges of switching off and on, hence that's why the timer will have been on the output side of the transformer between it and the lamp.

    Regards,
    Mike
     
  3. Bram M

    Bram M Member

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    Hello Mike, thanks for the reply.
    That's exactly what I was wondering about: does the transformer mind being switched on and off all the time, and could this cause a delay in the exposure? Anyone has experience with this?

    Thanks again,
    Bram