A visitor appears on the wallpad's video screen. Seeing who is at the door is easy; unlocking it still means walking to the entrance. Our home did not have the integrated wallpad-and-door-lock feature common in many newer apartments.
At first, you might assume the solution is to replace the entire wallpad or door lock. I decided to investigate whether the existing lock could gain just the communication function it lacked. That decision became the starting point for several later automations.
The wallpad and door lock did not need to become one device
Our original wallpad displayed the video doorbell. The lock opened with a fingerprint or PIN. Each worked well on its own, but there was no connection that allowed the wallpad to unlock the door.
The frustrating part was not that either device was broken; it was having to walk over every time I needed to perform the missing action. I could see a visitor on the screen, then had to go to the entrance to let them in. Remotely, I could only share a PIN with someone who could not get in.
Instead of trying to wire the wallpad directly to the door lock, I connected the lock to a separate smart-home hub. The wallpad could keep doing what it already did: show me visitors.
Choosing a Zigbee module instead of an RF module
Our door lock supported an optional wireless communication module. I used a compatible Zigbee module, SHP-DADT301/CN, in place of the original radio-remote (RF) module and paired it with the SmartThings Station we already owned.
Despite the complicated part number, the idea was simple: keep the lock and add one route for communication.
There is a crucial compatibility warning. Not every RF module can be swapped for a Zigbee module. A similar connector or housing does not establish electrical or software compatibility. Verify the exact lock model, module specification, and hub support applicable to your device. My past combination may not work with every product sold today.
Zigbee and Z-Wave are also different radio standards. This was a Zigbee setup, and not every device advertised as "Zigbee" works with SmartThings Station.
The moment I actually needed remote unlocking
Remote unlocking proved useful when a family member phoned from outside the front door after several failed fingerprint attempts.
There had been an earlier incident when repeated authentication failures triggered a loud warning sound, making the situation more stressful. Because the family member normally used a fingerprint, they could not remember the PIN right away.
When they called to ask me, I could not remember it either. Under the old setup, both of us would have been stuck for a while.
This time I opened SmartThings on my phone and unlocked the door. What I remember is not the door moving, but a remote-control feature solving a real moment of difficulty.
It also helped when friends or family arrived before I did. I could open the door when needed without handing out its PIN.
The button beside the wallpad supplied the missing function
Once the lock was connected to SmartThings Station, I wondered if a separate button could provide indoor unlocking as well.
So I installed one smart button beside the wallpad, configured to unlock the door when pressed.
I did not modify the wallpad's internal wiring or buttons. The wallpad still handled video, while the smart button and connected lock handled unlocking. It looked like a small addition, but made a common action much easier.
I liked that I could fill a gap without rebuilding the entire house. Separating the roles of existing equipment and new functionality meant replacing less.
More convenience required more security care
A door lock is different from a lamp or vacuum cleaner. A mistaken action directly affects access to a home. Successful connectivity alone is not sufficient evidence of a safe installation.
Protect remote-control accounts with strong authentication, and keep authorized users and devices to a minimum. Place indoor buttons where outsiders cannot reach them. Avoid automatically unlocking a door without verifying the visitor. Specific security behavior and SmartThings functionality vary by lock model and support status.
Module installation also needs care. Unsupported components or unauthorized modifications can cause malfunction or warranty issues. Check manufacturer compatibility and supported procedures, and avoid an installation whose safety cannot be established. Preserve a normal manual way to enter if remote control is unavailable.
One small connection became a condition for other automations
At first I only wanted to unlock a door remotely. After adding that capability, door events also became possible conditions for other automations. I tried connecting entrance events to lights and the robot vacuum.
Not every experiment worked. Different family routines made it difficult to infer arrival or departure from a door opening. Eventually, some of these ideas returned to simpler button controls.
The most important lesson was that a useful missing function could be added without replacing the whole door lock. A good smart home does not have to be a house in which everything was perfectly integrated from day one. It can be a house where existing gaps are solved pragmatically.
In the next article, I describe how two failed remote-control experiences changed my criteria for choosing devices.