How many I/O and what are they for.???

[Kitwn]

Some applied cunning can reduce the total number of outputs needed if you are limited. My cheap Chinese BOB has a total of one! The cooling pump is on the same mains switch as my VFD and runs continuously which allows better post-job cooling in my opinion and so doesn't need a BOB output. The one output is used as the spindle start output but is also used to switch a mains relay which starts the dust extraction.

[JAZZCNC]

The cooling pump is on the same mains switch as my VFD and runs continuously which allows better post-job cooling in my opinion and so doesn't need a BOB output. The one output is used as the spindle start output but is also used to switch a mains relay which starts the dust extraction.

Often VFD's provide an output Relay which you can use to turn on the water pump when spindle starts or have it turn on another relay which starts water pump and Vacuum when spindle starts. Better than having a pump running all the time VFD is on but spindle not spinning.

You will probably have to change a parameter in the VFD because often the relay is set to activate when a fault happens but can be set to turn on when start command is given.

[Kitwn]

Often VFD's provide an output Relay which you can use to turn on the water pump when spindle starts or have it turn on another relay which starts water pump and Vacuum when spindle starts. Better than having a pump running all the time VFD is on but spindle not spinning.

You will probably have to change a parameter in the VFD because often the relay is set to activate when a fault happens but can be set to turn on when start command is given.

Thanks, I might look at that. My main point was to show that you can get away without lots of outputs on your controller since that is the subject of this thread.

[JAZZCNC]

Thanks, I might look at that. My main point was to show that you can get away without lots of outputs on your controller since that is the subject of this thread.

Ok and in the spirit of "One-Up-man-ship", I can top that and say my machine doesn't use any Outputs as it's got a "Carbon-based pointing device operating system" ie: my finger which starts the spindle...