While I understand the basics, electricity still seems like magic to me. (I'm a software guy). I would like to use an Arduino to control some fans that cool my entertainment center cabinet. However, I don't want my lack of knowledge to end up starting a fire.
Feel free to ridicule me if I'm being needlessly paranoid, but here's my situation:
I have an AC/DC adapter
soldered to a 2.1mm plug. It is regulated, rated at 800 mA, and UL listed. I'll use this to power the Arduino 24 hours a day. Three 120mm case fans will be attached to the digital output pins. The fans are rated at 80mA (@12V) and will be switched on or off (no need to PWM) based internal temperature of my cabinet.
What would happen if I accidentally caused a short to the power supply? What level of safety does the UL listed mark imply? Should I put in a fuse? Buy insurance?
Any other standard safety procedures for electronics projects?