Switch Open Closed

[christian6b]

Trying to get a doorswitch status in my motor home, has tried with digital and analog in but no open or closed status. The problem is that I need a resistor between the arduino otherwise the lamp is on even the doorswitch is off.
The only working results is with value on analog in.
Attached a Picture on the working results.
My English is not the best, but i hope the Picture can explane better..


Best Regards

[christian6b]

Changed the resistor to 1k and now it show status on the digital ports. Any advice to the right value on the resistor..

[email68]

I probably shouldn't respond since I don't know anything about ardrino's, but here's how I would approach it.

I'd replace the resistor with a diode, and make sure there is a pull-up resistor like I show. It maybe already on the board. Is the ardrino 12vdc powered? I only bought a relay board once and it's 5vdc.

This will work either way as long as the pull up resistor is setup like my drawing.

Good luck!

[enigmatheatre]

Why not just use a 12v relay?

[randy]

A relay would work as would the drawing above, but you really don't need the 10K pull-up resistor as the Arduino's pull-ups are on by default. All you need is the diode to isolate the input from the +12V supplied through the light, or allow a current path to ground when the switch is on. The diode can be a very low current fast switching diode.
.

[christian6b]

The 12v relay works perfect with the ground from arduino, but the diod should also work. i only tested diod with high values and it works sometimes. I buy some diods today with low value and test

[christian6b]

now its working with the diod also, very fast response. The only problem now with the diod is that homeseer dont switch image status, but the rest works events, etc... Any idea?
Many thanks for the help.....

[petez69]

In the device setting you will need to select an image that corresponds to the device value....

[christian6b]

Changed back to the 12v relay and Everything works perfect again, i think the best is not to mess with the 12v system...

[petez69]

The relay is a HUGE overkill, the diode will do the job...though if you are using the digital inputs using a relay or diode should be no different to the status values...

[christian6b]

I agree its overkill, and the diode should work, but the relay works perfect and a leave the 12volt system by itself. My next switches is front in the truck and there is 24 volt so i go with the relays with same setup. Thanks

[petez69]

Good work mate, you got it going, that's most important :-)