Breakout boards

I've been converting a manual mill to cnc and I'm using a c10 breakout board with a separate relay board to turn the spindle on and off.

I noticed when I turn the computer off the relay board activates the relay and turns the spindle on and stays on until the computer is turned on again.

Is there a way turn the computer off with out activating the relay board and turning on the spindle?

The best way would be to add a chargepump to the system, that way Linuxcnc has to be up and running to turn it on. (CNC4PC sells one and they have wiring instructions on their site for connecting it to the C10.)

But if you are less safety conscious you might be able to get by hooking your spindle control relay to a different output pin, one that is in the state you need when the computer is off. (pins 1,14,17 are hardware inverted and may give different results than others when turned off.)
But this isn't a guarantee of the pins state when Linuxcnc is not running.

Sorry for the delay. The relay is wired to the no contacts and when the computer is on all is good whether Linuxcnc is running or not.

The charge pump sounds like the best way to go so I think I'll get one ordered today.

Thanks.

Do you have a manual switch in the motor circuit so you can be sure that the spindle cannot run while you are changing cutters
or the like? I have one in mine.
l

I don't but I should it would be a bad day if the spindle turned on during a tool change.

Thanks for the idea.