Hello everyone, I’ve recently gotten into the world of HomeMatic and decided to dive in headfirst. I came across the HM-MOD-RPI-PCB module, got myself a Raspberry Pi 3, and got to work. After some initial hurdles, I managed to control a HomeMatic light switch through the Raspberry Pi. I installed OpenHAB 2 along with Homegear on the Raspberry Pi, and everything has been running smoothly and reliably.
Now, I’ve taken the next step and purchased the HM-Sen-DB-PCB Doorbell Sensor. It was a quick soldering job, and my setup recognized the device right away. I immediately set up a rule where, whenever the sensor detects a voltage change (which happens when someone rings the bell), it sends me a Telegram push notification. This is done using the OpenHAB Telegram extension.
However, no matter how I connect the sensor, it doesn’t seem to work as expected. I’ve tried various configurations, including checking the circuit diagram, measuring the voltage, and even reinstalling the sensor. Despite all these efforts, the sensor doesn’t trigger the notification.
Interestingly, when I bridge the Input and GND terminals with the doorbell wire and a 9V battery, the sensor works perfectly, and I receive the push notification instantly. This suggests that the sensor itself is functioning correctly, but there’s something wrong with how it’s connected to the doorbell system.
I suspect the issue might be related to the voltage from the doorbell transformer, which measures around 13.5V to 13.8V when the bell is pressed. Could this higher voltage be causing the sensor not to trigger? I’m at a loss and would greatly appreciate any insights or suggestions from the community.
Thank you all for your help, and I look forward to hearing from you! Cheers,
[Your Name]