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The PC interface

The device that interfaces these alarm boards with my server, and my phone, is the Zooz Zen17 Universal Relay.

I chose this product specifically to interface with my Z-wave network, a low power short range 900MHz wireless network for home automation. This device is also very cheap (considering the amount of I/O and the general cost of Z-Wave devices) and can run on 12-24V DC as well as USB power.

InstalledThe Zen17 has two each inputs and outputs: two line-voltage rated relays, and two sets of "dry contact" inputs (two sets of "common 0V" and "sense" pins, and when they are shorted together, the input is detected as "on".)

A useful feature of this device is that the two S1/S2 inputs can be specifically designated as generic smoke and CO alarm senors. This is set in the Z-wave configuration for the device, which I won't go into here.

By default the inputs and outputs are tied together: input 1 is triggered, and relay 1 is activated. The state of the inputs is monitored on the Z-wave network, and relays can also be triggered manually via the network (and in my case, HomeAssistant). I also changed the configuration to separate inputs and outputs, since I am not currently using the relays to do anything, having them activate with the alarms just adds uneeded wear and tear.

Here is a closeup of the relay box installed next to the UPS and interfacealarm boards,relay itbox:

was

20221211_125429.jpg

easy to integrate. Set up

With the Zen17two asabove such:configuration separatechanges, the inputs from outputs (so inputs do not trigger relays), and change the inputs from generic IO to Smoke/CO alarms (this only really changes the labels in monitoring software, but it's convenient.) Run the NO wires from the signal board relays into the S1/S2 signal inputs on the Zen17, and the COM wires to the "C" (common) input next to them. Finally, ran 12VDC power from the UPS (using the second installed barrel jack) for steady power.

[pics of all 3 boxes next to each other and wired up.] [Close-up of relay box IO.]

I usemade two simple HomeAssistant to"automations" monitorthat andsimply control my Z-wave network, so I used the Z-wave integration to set up alerts tosend my phone (NOTa emails, just app notifications)notification when one of the inputsalarms gogoes live.off,.

InFrom HA,a setblank upautomation automations (start blank):template:

Trigger:
  - type: Device trigger
  - device [choose the dual relay box]
  - Trigger: "Smoke Alarm Becomes Hot"/"CO Alarm started detecting gas" [choose 1]
  - Duration: 1 sec
  
Action:
  - type: device
  - Device: [choose your phone]
  - Action: Send Notification
  - Message: "SMOKE/CO ALARM HAS ACTIVATED!!"
  - Title: FIRE ALARM

If you did not change the input labels, the trigger will be something generic like "input S1 has activated", but the rest will be the same.

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