Float switch on 7i96

Hi guys,

Having a hard time figuring out my float switch. I am using a microswitch and I assumed (and from what I understand in the Mesa manual) it would go one conductor as an input and the other to the input common on the 7i96. I have looked at the wiring diagrams available and none of them are quite like what I am doing.

TIA.

I have a 24V field power supply:
0V connected to input common.
24V connected to the float microswitch.
The other side of the float microswitch connected to input8.
 

7I96 inputs are wired like this:

For sourcing inputs

Input common (TB3 pin 12) <-- +5 to +24V
Inputs 0 through 10 (TB3 pins 1 through11) connect to
ground (+5V +24V common) to activate

For sinking inputs

Input common (TB3 pin 12) <-- ground
Inputs 0 through 10 (TB3 pins 1 through11) connect to
+5V ... +24V to activate

And what is the difference between sourcing and sinking? Just in the way you set them up?

If I read correctly, the easiest setup is provide 24v to the microswitch and then the opposite side of the switch to an input on Mesa, when switch closes I get a 24v signal to the input, telling Mesa that the switch is activated. So sinking?

I still don't understand how the common works. I have a bunch of npn sensors, I provide them with field voltage and the signal wire to an input on the Mesa, linuxcnc sees those just fine.

For sourcing inputs (that work with NPN sensors)
The input common goes to +5..+24V

For sinking inputs the input common goes to ground

So if you have NPN sensors, you should connect the
input common to +24V, and any switches would
connect the 7I96 inputs to ground