adding magnetic contacts to alarm

[MyFartsStink 10+ year member]

We want to add some magnetic contacts for the the work trucks rear hatches. There is three total and the magnetic contact is normally closed when they are apart. I want to hook them all up in series with a 12 volt and a combination of a relay to send the alarm door trigger a negative signal. I have a wiring diagram of how I just only hooked up one of them to see if it would work first. It seems like I got it right, but I cant get the alarm to sound when I test it. I hear the relay click every time I move the contacts close to each other. I dont know what I am doing wrong can someone help me fix this problem?

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[Worlddre 5,000+ posts]

there is no purpose for a relay in this application simply wire them to the alarm and diode isolate

 

[MyFartsStink 10+ year member]

there is no purpose for a relay in this application simply wire them to the alarm and diode isolate

Are you saying I should hook up one lead to a ground then hook the other to the door trigger input through a diode? If so I already tried this and it didn't work.

 

[Worlddre 5,000+ posts]

diode was backwards but yes thats all you have to do.... if only using one skip the diode...more then one start using diodes making sure the stripe is on the side facing away from the alarm

 

[MyFartsStink 10+ year member]

diode was backwards but yes thats all you have to do.... if only using one skip the diode...more then one start using diodes making sure the stripe is on the side facing away from the alarm

did you not look at the diagram?

 

[Worlddre 5,000+ posts]

If you plan to use a relay anyways you need to ground 87 not 87a however the relay is very much not necessary.

 

[THUNDERBIRD 10+ year member]

x2