First of all I know there are many similar questions answered but I'm still a bit unsure on why my current set up doesn't work. I'm really outside my area of expertise so be kind.
This is what I have:
6 wire cable connected to door strike. I don't want to to dismantle the door to see how it's really connected so I'm assuming red / black is positive and blue / white is negative. Does that seem correct?
Arduino that controls a relay. This part works.
DC Power adapter - 12V 1A
So I have connected the positive wire from the power adapter to the com port on the relay. Then I have twisted together the red and black wires from the strike and connected it to the NC port on the relay.
Then I have connected the negative wire to the blue and white wires.
But when the relay switches on nothing happens. What have I done wrong? What should I do to trouble shoot it. Should I add a diode like in datasheet?