I was at an OB a few years ago, where a Producer was standing in the Satellite truck - leaning against the wall. He was holding onto the a rail in front of the breakers, and did actually knock one off - taking the programme off air! Luckily, it wasn't the circuit that had the satellite coder/HPA on it, and TX was restored quite quickly. It's been a talking point since!
A colleague (very wisely) once stopped me from using the USB port on the aircon control PLC on an OB truck tailboard to charge my phone from mid broadcast. He was quite right too, given the chaos of suddenly having Windows XP and ios being shoved together !