How would you solve this?

[jbbtex]

My alarm system has four entry door sensors that are hard-wired in series to one sensor input. I'd like to use the door sensors for HS.

Do any of you have suggestions as to how to do this and still have all four door sensors "connected" to the alarm?

I was thinking about using an Arduino.

[sparkman]

My alarm system has four entry door sensors that are hard-wired in series to one sensor input. I'd like to use the door sensors for HS.

Do any of you have suggestions as to how to do this and still have all four door sensors "connected" to the alarm?

I was thinking about using an Arduino.

Hi Brady, what kind of alarm system is it? Can it be interfaced to HS? This would be the prefered way to do it. If not, you could use something like you suggested and have it trigger a relay. The relay can connect to the terminals on the alarm system. This does add a failure point to the alarm system. Alternately, you could find a non-intrusive way to measure the current in one of the sensor wires. Could be done with an Arduino and a current sensor.

Cheers
Al

[jbbtex]

Thanks for you input, Al.

The alarm is a Napco GEM-3200. I could upgrade the chip so that it would interface with the HS plugin, but I'd also need an expansion board in order to split out the four door sensors. Weighing the cost, I'd be inclined to just change the whole thing out for a DSC. That's my preferred option.

However, convincing my better half that there is even a problem that needs to be solved is easier said than done.

I'll probably continue to think on it for several months before I actually do anything. I have zwave & insteon sensors on the doors at present. But I'd like to get rid of them because they're a bit unsightly.