My Smoothieboard is all fine and working well but I was a little worried about noise and isolation of the different power supplies plus the possibility of any voltage spikes damaging the board.
My setup is for a pick and place machine, I have a 36V supply running two large steppers on separate drivers with no connection to the Smoothie other that step, direction and enable.
I then have some small steppers using the onboard drivers and these run off a 24V supply to the board and soon I want to connect some noisy items with motors and solenoids to the mosfet connections on the board, do I need to take any measures to protect anything (I was going to add diodes close to the source for these). Are these ok on the same supply as the board?
Currently I have no 5V supply to the board so it is powered by either the USB connection or the 24V supply, I’m not sure which one is doing the work with both connected. should I use a separate 5V supply? Would that provide better noise isolation?
Also does it matter in what order I power on the supplies? At the moment I power on the 36V and 24V together and then connect USB.
I have a 36V supply running two large steppers on separate drivers with no connection to the Smoothie other that step, direction and enable.
This means opto-isolation for Smoothie, which makes it completely safe, you really shouldn’t worry.
motors and solenoids to the mosfet connections on the board,
Make sure you protect the mosfets with diodes, kickback from coils can be dangerous. You generally shouldn’t worry about the power supplies themselves though.
Are these ok on the same supply as the board?
Sure.
should I use a separate 5V supply?
If you’ve got several 5V supplies to the board, Smoothie uses the one with the highest voltage ( see http://smoothieware.org/logic-power ). You can figure out which this is by measuring, but it really should’t matter much.
Using a 5V PSU is generally a bit better, but it really shouldn’t matter too much.
In general, you seem to be doing things fine, and shouldn’t worry too much until trouble actually starts showing up.
Also does it matter in what order I power on the supplies?