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

[JAZZCNC]

Now it's OUTPUTS.

You tend not to use as many OUTPUTS as you do INPUTS which is why you'll often see cards with 5-IN 2-OUT or 12-IN 6-OUT etc.
OUTPUTS tend to only handle low currents so they mostly are used to turn on other devices like relays or Transistors which only draw low currents but can handle heavier loads through their contacts etc.

Some common uses for OUTPUTS are Spindle ON/OFF, Coolant ON/OFF, Vacuum ON/OFF.

But again they can be used for just about anything and going back to the ATC type setup of a more advanced machine they would be used to control pneumatics. So the Drawbar to release the tool would have a solenoid which was controlled with an OUTPUT, the carousel would have a motor that was turned on/off to rotate it to the next tool or motor or pneumatic actuator to move it in or out of position.

So OUTPUTS turn things on or off, that could be anything from a light bulb to a Kettle and again going back to the control panel with INPUTS sending Signals from button presses an OUTPUT can do the opposite and send Signal OUT that reacts to that INPUT press so for instance when you press CYCLE START it could turn on a lamp on the panel.

Again only your imagination and the amount of I/O you have can limit what can be done.!

Hope this helps some of you and just ask if not sure of anything.

Edit: Suppose I should mention this for clarity.! There are also ANALOG I/O's.

These are similar to the standard I/O but they accept or output a voltage range usually 0-10v or 0-5v.

These would be used for things like controlling the speed of a spindle where an A-OUT would send a voltage based on the commanded speed, so, for instance if you had a 24krpm spindle, 0v= 0 rpm 10v=24k so if you command 12,500rpm then approx 5.2v would be sent from the A-OUT to the spindle controller.

Likewise, the A-IN would accept a voltage between 0-10v. These would be used for things like setting up external feed override or Spindle override dials using a potentiometer or Spindle Load or RPM feedback from spindle controller. THC (torch height control) on a plasma is another use for A-IN

So basically an ANALOG I/O sends or receives a voltage range to do with as you please.