Episode Details

Daniel is a renter who built a Home Assistant security system with Zigbee sensors, but he’s worried about coin cell batteries failing at 3 AM during a break-in. This episode breaks down the real-world battery life of CR2032 cells, why the voltage discharge curve makes percentage alerts unreliable, and exactly how to wire sensors to a 5V DC power supply instead. We cover the specific sensors that accept external power, the wire gauge and current specs to tell an electrician, and how to use surface-mount raceway to run low-voltage wiring without violating a lease. Plus: the exact script to use when calling an electrician so they hear “Class Two power supply” and “NEC Article 725” instead of “Zigbee.”