How to detect open/closed gate without the usual door sensor?

Tags: #<Tag:0x00007f325997f418> #<Tag:0x00007f325997f328>

I have a gate I can open/close automatically, but I’m struggling to get the state (=is it open or closed?). The problem is: I tried a zwave and a zigbee door sensor, but since the gate is metal, it interferes with the magnets the sensor uses, so it’s not reliable.

Do you have an idea how to detect open/closed in another way? I personally thought about using my doorbell camera I will add in the future. But maybe there are other options, or different kind of door sensors.

How about a limit switch? You can even wire one into a cheap zigbee door sensor in place of the reed switch. Plenty of different styles of switch to choose from depending on your gate design.

1 Like

Thanks for the advice! I didn’t use those switches yet. They need a power source, right?

No, just hack the existing ZigBee door sensor and wire the limit switch in place of the existing reed switch. (The ZigBee sensor uses a reed switch which closes when the magnet is brought near it)

I found in the manual of my Fibaro door sensor it’s even described how you can connect it, thanks for the advice! Can every limit switch just be connected like that, or are there types of connection? (I know there are different end points, like a wheel etc, it’s not about that, it’s about the wiring).

No worries, glad I could help.

Wiring wise, most limit switches will have both Normally Open and Normally Closed contacts so you can use whatever suits the particular application. For your gate you would want to use a set of contacts which are closed when the gate is closed. This is where some people get confused because that means using the Normally Open contact since you will have the gate push the limit switch when closed, thus closing the contact.

1 Like

Thanks, finding out about the limit switch being linkable made my day yesterday :slight_smile: The “gate problem” is a 2 year old puzzle that will get solved that way!

Awesome! Which model Fibaro sensor is it that you are using? The one I looked at didn’t mention a way to connect an external switch… though it could still be hacked to do so.

Hmm… actually, it’s not specifically mentioned in the manual of the type I use, but the previous version mentioned it in this manual: FGK-10x-EN-T-v2.0.pdf (fibaro.com)
I’m not at home (for some weeks), so I will only be able to test it out somewhere in January.

I do remember that model and thinking it was great to have a spot to wire in an external device. Well if the one you have doesn’t specifically have it, a little modification should solve the issue.