Sensor + Interrupt questions

  • Hey All,
    I have done some stuff with normal buttons and interrupts to wake up a node. I am wondering if anyone has done other stuff on the interrupts? Like a moisture/water sensor? im checking the feasibility of doing battery powered leak sensors. Seems like it would work since it's basically doing a button press by conducting through the water.

    Now, I know what the first response is.... just try it!! I would, but alas i don't have my water sensors here yet 😆


  • I swear I did a search. But apparently I searched on one of my other community forums that had nothing to do with arduino or mysensors 😆

    helps when i search the right forum.

  • @CrankyCoder

    I have a similar (same?) sensor type running on a Pro mini.
    I uses a PNP to gain up the sensor current and ran it into INT1 . My RFM69 uses INTO.

    Works perfect. I've been running it on 3 AAA *** Carbon! batteries for a few months to see how long the batteries work. I can't yet estimate the battery life because I'm using the internal measurement of Vcc (which goes through the regulator).


    *** updated, the original post stated 2 AAA batteries. This was in error.

  • nice 🙂

    I ordered a couple of sensors yesterday so as soon as they come in ill start doing some testing with them.

  • Mod

    @johnrob why are you using the regulator?

  • @CrankyCoder
    For sensors I'm using 4 stainless steel screws extending out the bottom of a plastic housing. They are spaced at the corners of a 5/8 square. I tested it with 2 screw and it worked fine but I went with 4 for the extra sense current.

    I'm using 3 AAA batteries, my 2 AAA carbon battery statement was in error. When fresh the voltage exceeds the RFM69 input voltage specification.


  • Mod

    you could use 3 ni-mh and get rid of the regulator, that drains battery fast unless you use a low quiescent current one.

  • Hi CrankyCoder,

    I have door/window sensors running using interruptions. I got rid of the regulator and the power led and I am using a step up converter to take as much juice as possible from the batteries. The oldest node has been running for a year already on 2 AA batteries so your project is definitely doable.

    The problem could be in case the leak sensor throws a lot of false positives in which case it would drain the battery quicker.

    I hope it helps.


  • @david-cabañero Thanks David, i just got a few of the step ups so I will give that a shot. Because of some of my other projects I have TONS of 18650 cells laying around so I figure those are decent batteries for this.

  • Mod

    are you running your nodes at 5V?

  • no, i have a couple that i am running at 3.3 off the 18650s. so far it's been pretty good just using the sleep