Post a link to the relays, or relay modules, you are using. Post a wiring diagram showing how you have connected them to the Pi.I am controlling a series of relays using the GPIO pins on a Raspberry Pi 4 Model B. Originally, I had a 5V and ground pins pins on the Pi connected directly to the VCC & ground pins on the relay, but added a breadboard because I needed to split the connection to a second relay (and generally make the system more scalable).
When I booted up the Pi after the rewire, I definitely heard a "pop," and thought I saw a flash, emanate from inside the Pi's case; naturally, I was afraid I had shorted the 5v pin. But once it finished booting, everything was working normally and the relays all turned on and off as expected.
Is this normal behavior, or should I be worried? I'm mostly concerned that it didn't short this time, but that there might be cumulative damage from each subsequent boot. I will probably eventually give the relays their own dedicated 5v power supply, but should I avoid using the Pi's pin in the interim?
Statistics: Posted by ame — Fri Jul 04, 2025 10:01 am