[Qicker306]

I'm in the process of gathering materials for the control panel of my XZero CNC build. I will be using a UC300ETH-5LPT and a MX4660 powered from a 48V power supply. I will also have 5V (UC300ETH power) and 12V power supplies for other items (LEDs, relays, solenoids, etc.). My question comes down to the negative terminals on all 3 power supplies, do I want to wire them all together? Is it best practice to have a common DC negative?

While on the topic of power, any info regarding fuses or breakers would be helpful, both for the AC and DC circuits. The system will be fed by 2 x 120VAC 15A circuits, 1 to power the controls and 1 to power the router (relay controlled). Should I be fusing these inside my panel? Should I fuse the individual loads off these circuits (3 x power supplies, router) Sized for the expected loads? Should I be fusing any of the individual DC circuits?

Thanks

[Al_The_Man]

If there is no other extenuating circumstances, this is the method I prefer and have used so far without any problems, also the commons are connected to the star point Earth ground plate connection.
Some manufacturers of equipment in this environment specify to keep everything isolated which in most case I believe is a theory that if everything is kept separate there can be no come back in blaming their product.
Also if P.C. based such as Mach etc, the P.C. port common is at earth potential already.
Al.