For anyone that may have followed my adventures in the Aeon Labs Aeotec ZW056 doorbell post, I’ve been recommending a smart doorbell sensor for awhile in the Must Have Home Automation Devices page, as a means to receive phone notifications and trigger other actions when your doorbell is rung.

There are more complex and expensive doorbells out there such as SkyBell and Ring that include cameras and two-way communication, but I really do not care for how bulky and obtrusive these devices are. I want my home entry to be clean and welcoming with a simple door bell. I still may have a discreet security camera in the corner of the entry-way ceiling, but it doesn’t scream “I’m watching your every move” to friends and family as does a camera-equipped doorbell.

“You can ring my bell.” – Anita Ward

I could not find a SmartThings Hub device handler for the DB100Z so I ended up writing my own (details and download information below). Aside from Nexia and now SmartThings, I haven’t seen that this device has yet been made compatible with other Z-Wave capable controllers, such as Universal Devices, or Vera. I tested briefly with HomeSeer Zee S2 and was able to get battery levels, but doorbell notification (power management notification, power applied) appeared inconsistently for me and I will need to investigate further. I verified that although it did pair with the Almond+, I was unable to receive notifications on the Securifi unit.

The doorbell saga

Nexia-DB100Z-DoorbellI recently reviewed the Aeon Labs Aeotec ZW056 Z-Wave Doorbell and although in general it worked fine for me, the Aeotec doorbell push-button itself was just not something I wanted to place in my front entryway from an aesthetics perspective. I also wanted to keep my existing conventional door chime; I did not want to rely solely on a wireless battery powered device to notify me of a doorbell press.

Although I did not end up using the Aeotec ZW056 as a doorbell, I did find that the included Aeotec doorbell speaker works well for me as a relatively inexpensive Z-Wave speaker for home event audio notifications. I am currently using this device to audibly announce events in my home, such as “water heater leak detected” and “garage door is open”. See the full Aeotec ZW056 Z-Wave Doorbell Review.

After reluctantly putting the Aeotec doorbell button on the shelf, I had to once again resort to recommending a roll-your-own doorbell device using a dry contact bridge and Z-Wave relay, even though I hadn’t ever actually gone to the trouble of implementing one of my own.

Is it – the One?

So far it’s looking like the Nexia DB100Z Z-Wave Doorbell Sensor may be just what I was looking for. At 3.25″ x 2″ x 1″, it’s reasonably compact (at least compared to a dry contact bridge and relay) and can be placed fairly discreetly within or around the doorbell box assembly.

My only complaint so far is that I wish there were an option to power this device using the low-voltage doorbell transformer itself, for those with easy access to the doorbell power source. The arduous chore of replacing device batteries flies in the face of the convenience that home automation systems promise, and I wasn’t looking forward to yet another device that needs continued battery replacement. I haven’t yet seen battery life projections for the DB100Z, but I’m hopeful that its two AAA batteries are more than adequate to keep this device powered for several years.


Nexia-DB100Z-Doorbell6I was able to install the device in just a few minutes. Although it comes with two screws for wall mounting, I chose to mount the unit on top of the doorbell box using (not included) double-sided tape. It blends in fairly well with my doorbell assembly – and who really looks up at the doorbell anyway.

The device works by detecting the voltage used to power a conventional doorbell, and requires typical doorbell voltage between 14-40 VAC.  The DB100Z is conveniently designed so that the wires from the doorbell connect to terminals on its back plate. It is the back plate itself, and not the main device assembly that is installed on your wall or doorbell cover, so that you can easily snap the main body off to replace batteries or to drag the device to another room for easy pairing.

If you have a Nexia bridge, the DB100Z is recognized by default during pairing. If you have a SmartThings Hub, you can save a step by first installing this custom device handler per the steps below before pairing. If you’ve already paired the SmartThings Hub with the doorbell sensor, you can change the device type in the SmartThings IDE to the Nexia Doorbell Sensor after pairing, and it should work fine.

Device driver, setup and pairing

With the DB100Z cover removed, pairing is accomplished with a single press of the install button on the device. When added to a SmartThings Hub with the custom driver installed, the device will be recognized as a “Nexia Doorbell Sensor” automatically during pairing.

Device exclusion is also performed with a single press of the install button. Although the manual states that resetting the device back to factory settings is accomplished by pressing and holding the install button for 10 seconds, I found that with my device, I had to press and hold the button for about 15 seconds until I received a blinking LED confirmation.

Here is the Doorbell Installation Guide, and configuration capabilities can be found here. The doorbell sends a version 2 Notification Report event 1 when current is detected and an event 0 when it stops.  Battery level is sent in a Battery Report and is a simple integer percentage value.

SmartThings Hub device handler details

Writing the device handler was a little more complex than I was expecting – primarily due to an occasional missed message and the occasional out of order message sequence. I’ve implemented code to work around these cases.

Device Handler Download Locations:

The initial 1.0 Nexia DB100Z Doorbell Sensor Device Handler for the SmartThings Hub can be downloaded from the following locations:

Installing the Device Handler:
  • Login at
  • Select “My Device Handlers” and select “Create New SmartDevice”.
  • On the “Create New Device Handler” page, select the tab “From Code”, and paste in the code from either of the above links into the IDE editor window.
  • Click the “Create” button at the bottom.
  • Click the “Save” button above the editor window.
  • Click the “Publish” button and select “For Me”.

The Nexia Doorbell Sensor device handler is now ready for use.

There may be some oddities when used with different doorbell types, so please let me know of any issues. Any and all suggestions and updates welcome.

EDIT 17-Sep-2018:There have been reports of cases where the DB100Z does not signal events when the doorbell button is pressed and released very quickly, despite the chime itself ringing. I’ve personally seen this behavior with the DB100Z using both the SmartThings Hub and HomeSeer controller. While I haven’t personally tested the DB100Z with the NuTone transformer shown here, I have heard from one user that replacing his existing transformer with this transformer and using its 16V 20VA terminals solved the “quick-flick” issue for him.

Reference these related Feature Comparison Tables: