The board components are all IMserve / Desk CNC components. The power supply is a combination of parts obtained from Allied electronics and IMserve. Other parts are from Radio Shack...
I control all power functions with solid state and reed relays that use 5v activation. 1N914 diodes isolate the relays from the controller board. I use a 5v auxillary plug in power supply to act as a relay activation voltage with a momentary reset push button switch.
When the servo box is first turned on,, only the fans and 5v auxillary power supply are powered up. pushing the reset button activates the main DC power relay. once the power supply is on line, a separate 5v tap keeps the relays latched. The reset voltage is isolated from the controller by diodes.
The latch voltage is supplied through a FET transistor which is held closed by the servo fault circuit. If a servo axis faults, main DC power is cut. This shuts down the controller and all other functions. This type of circuit can also be wired to activate an Estop if desired.
There are override switches to bypass spindle, coolant and index to aid in machine setup and program testing.  |