After struggling with an outdated intercom system, I stumbled upon an ingenious solution using a Xiaomi humidity sensor. Here’s how I transformed it into a smart doorbell notifier!
The Challenge:
Our rental property had an old intercom that was both noisy and unreliable. Every time someone rang the bell, it would blare loudly, disturbing the peace. Plus, the intercom didn’t integrate with our smart home setup, making it hard to monitor remotely.
The Solution:
I discovered that the Xiaomihumidity sensor, when paired with Home Assistant and ZHA, could detect voltage changes. By connecting the intercom’s calling cable to the sensor’s battery terminals, I mimicked a battery change event whenever the doorbell rang. This triggered a state change in Home Assistant, which I then used to send notifications and play a custom sound throughout the house.
**Setup Steps:**1. Hardware Connection: I carefully connected the intercom’s positive and negative wires to the sensor’s battery terminals, ensuring no direct power source was needed.2. Home Assistant Configuration: I set up a state change trigger in Home Assistant to detect when the sensor’s state changed, indicating a doorbell press.3. Automation Rules: I created automations to send push notifications and play a soft chime sound in specific rooms, ensuring we never miss a visitor.
Benefits:- Customizable Alerts: Choose from various sounds and decide where they play based on household activities.- Energy Efficiency: No additional power source required; the system runs on the intercom’s existing voltage.- Discreet Installation: The sensor’s small size allows it to fit neatly inside the intercom unit, maintaining a clean appearance.
Unexpected Learnings:- The sensor’s sensitivity was crucial. Too much voltage could damage it, so testing with a multimeter was essential.- Using a USB battery pack as a backup ensured reliability during power outages.
This project not only solved our doorbell issues but also opened my eyes to the creative potential of repurposing smart home devices. It’s a testament to how a little ingenuity can turn everyday challenges into opportunities for innovation!