Two Reed Sensors with One Contact Sensor?

I’d asked about using reed sensors connected to smart contact sensors before but have another question: can I connect two reed sensors to the same contact sensor? I’m using the Ecolink contact sensor and hoping to use the two reed sensors on my windows that are next to each other on the second floor so monitoring of them individually isn’t important. If possible how would I wire them?

You would wire them in Parallel.

Assuming Reed Switches you’ve selected are Normally Open (N.O.) and Reed Switch 1 has two contacts, a and b… as does Reed Switch 2… then wire A of each to one of the contacts in the EcoLink, Wire the B’s together and into the remaining Ecolink.

When either reed switch closes, it closes the Ecolink contacts and sends the “Closed” state to SmartThings.

I’m looking to get these ones…

uxcell Plastic Housing MC-38 NO Normally Open Window Door Reed Magnetic Contact Switch Pair White

If the magnet is near the switch when the windows are closed wire it like this.

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Agreed. They should be wired in series so both have to be closed for the sensor to report closed to Smartthings. If either of them open, the sensor will report open to ST.

If I can ask another question: does anyone know how to mount these type of sensors?

uxcell Recessed Security Alarm Contacts Door Window Sensor Magnetic Reed Switch White

Where does that little round thing go?

With this diagram both reed switches would have to close for an alarm state. If you want the alarm to work the switches should be in parallel. This way either switch would close the circuit and put the alarm in alarm state.

Reed switches are typically closed when the door/window is closed. This ensures a cut wire will cause an alarm condition. Thus, they should be wired in series so either can “open” the circuit. Both reed switches must be closed to created a “closed” condition.

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I was referring to the diagram drawn above showing two open contacts. Yes normal alarms are normally closed. And I have no idea about this particular vibration sensor. But I also used the below post.

The little round thing without wires is a magnet. The is inserted into the edge of a door. The wired one is the reed switch, which is installed in the corresponding door jamb to be aligned with the magnet when the door is closed. This results in the switch being “closed” when the door is closed.

Ahh okay so then I’ll go with the other style like this…

I’m not sure how you’d do recessed sensors in a windows, particularly fiberglass ones.

I agree that recessed in a Fiberglas or PVC window is problematic. Also I read somewhere that some of the recessed units are not waterproof, and in a large rain the bottom of the window channel get good and wet. And in a Fiberglass window if not sealed properly the water will end up in the walls. I have used them in the side channel of a window as there is usually a wood backing or stud there. But I only know what I have seen in the few times I have installed them.

Just something to think about. With a GoControl contact sensor and a custom DTH. You can use both the internal and external contact sensors. This way you have the ability to monitor both windows. This of course depending on the #of wires available from the windows to the smart sensor.

With that setup would I need one or two reed switches?

This model?

GoControl Z-Wave Door/Window Sensor - WADWAZ-1