False triggers on Fibaro universal sensor

Hi All, I have installed a Fibaro universal sensor in my 3rd party alarm system to allow me to monitor 2 outputs and integrate it into my Vera3. I created the two inputs in Vera to be: Alarm ON/OFF and Alarm Triggered. I created a notification for Alarm Triggered to be sent to me.
My problem is that I kept getting Alarm Triggered notifications all day long, randomly. So to confirm that the issue was not my alarm switching its output randomly, I simoly disconnected the Fibaro inputs from the alarm panel. As I expected the notifications kept coming through. Why would I be constantly getting false reporting from this thing?

Any help would be greatly appreciated.


My assumption would be that when the output from the alarm is low you are getting whats known as a “floating” input to the fibaro and it is triggering.

Basically the input to Fibaro is neither high nor low, and is subject to static etc.

If you were to drive a relay from the alarm system instead and have the input to the fibaro switch between ground and high it would probably fix it.

As you have already disconnected the input and seen it happen, have you tried connecting the input to ground and seen if it still happens?

no i havent. I have only tried having the fibaro input floating / disconnected (other than when i had it connected to the alarm panel) so your suggestion is quite good. I guess the problem is going to be that this situation will always exist even if I use a relay. The fibaro input would still essentially be floating when the relay is OPEN. the fibaro sensor would only ever see a nice non-floating situation when the relay CLOSES and takes the fibaro input to ground… The way i have this setup (if using a relay or dry contact) is actually as per the fibaro instructions so it "should’ work.

rather than a relay change between open and closed, get a 2 position relay so it will be either connected to one or the other.
You then have Fibaro on the common terminal it will either be connected to the power or ground depending on the relay position.

ok I just realised what would also work, I can’t believe I didn’t think of it before lol

You could just use a pull down resistor on the Fibaro.
It goes parallel to the connection to the alarm output.

Using a high enough resistance (k ohms) when the 5v output is on it is such a high resistance it doesn’t effect the alarm.

When the output is low however it should be able to dissapate and “floating” voltage and stop it creeping up.


Yeah good idea. I will give it a try whe. I get back home in 2 weeks. The Fibaro sensor requires its input to be taken to 0V to register as an ‘active’ input so I guess I could use a high value resistor connected from the Fibaro input to 12V? (The Fibaro runs on 12V DC). This way the Fibaro input would be held high until the alarm output relay drags it down to 0V

however based on what I have read in the following thread, I’m not feeling confident that this will work. It seems that either the Fibaro sensors or the Vera integration is still going to cause trouble…