Good day to all, I'm a newbie to the site and I have a quick question for all you electrical geniuses out there. I will start of with a bit of insight into my question. I am a maintenance Controls Technician in the automotive industry who has some experience, in my earlier years, doing electrical design. So my question is as follows: Is it common practice to "ground," not bond, the common side of a DC power supply? I myself have only witnessed existing machines set up like this, never designed a circuit to be like this. My issues with this practice is that I was trained to never include both voltages on the same circuit. Also, if manufactures of said power supplies wanted this done why don't they include ground symbols/nomenclature or even internally jumper the 2 points as a common. I was also trained to "bond" all metal device together to avoid hazardous shocks due to stray current that has no where to go. I was also told "that's just common practice in all electrical circuits." If anyone has some insight in to this on going discussion I'm having with a co-worker would be appreciated.