Changing from a NO relay to a NC

Discussion in 'The Projects Forum' started by Karrion, Oct 19, 2009.

  1. Karrion

    Thread Starter New Member

    Oct 19, 2009
    2
    0
    Hi,

    I am wiring into a DVR so that when a camera detects movement at night the lights come on as the light don't have built in PIR'S

    I was originally told the relay on the back of the DVR would be Normally Open so I worked out the circuit around this (see drawing)

    I have been informed today that the realy is infact normally closed and I now struggling to see how I am going to do this.

    I am using a 24v AC to 240V contactor for the lights. My orignal NO circuit plan is shown on the image attached.


    Any help would be much appreciated

    Chris

    [​IMG]
     
  2. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    5,699
    907
    Easiest solution is wait to see the relay. Maybe it has both NO and NC contacts.

    Second, is the relay control 24V AC or 24V DC?

    John
     
  3. Karrion

    Thread Starter New Member

    Oct 19, 2009
    2
    0
    The relay is purely a NC relay. This is for security reasons in the event of someone cutting the cable.

    The power supply is 24v AC
     
  4. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,574
    230
    Re jpanhalt's question...What is the voltage of the relay on the back of the DVR...and is it AC or DC?

    Ken
     
  5. ol'trusty

    Member

    Sep 9, 2009
    48
    0
    YOu can add Another relay which is n/o
     
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