Building a Safe AC-to-DC Enclosure for MQTT Traffic Lights

Ready to move beyond USB bricks and build real mains-powered hardware? This episode walks through Daniel's project: a twelve-volt DC traffic light controlled by a Raspberry Pi running Eclipse Paho MQTT. We cover enclosure selection, the Mean Well LRS-35-12 constant-voltage supply, proper fusing with an IEC C14 inlet, relay isolation between Pi and LEDs, and multimeter verification per IEC 62368-1. This is the perfect entry point for learning AC-to-DC conversion safety while keeping the low-voltage side in the safe ES1 zone.