spindle with encoder

Ah, I took a look at the actual wiring on my machine. I get the A/B signals from the simulated encode in the servo drive and the Z (index) signal from the sensor that is looking at the slot in the disc on my spindle. That is how mine is able to work.

Thanks Andy

What this means?
That for rigid tapping encoder must be on spindle shaft
or must be on 1:1 ratio with spindle shaft?
Other ratio configurations can't work for rigid tapping ?

The index signal sent to the encoder input to LCNC must be 1:1 with the spindle. My encoder is on my motor. But, I get the index signal from the sensor on my spindle. If the gearing of the motor to the spindle was exactly 1:1 you could attached the encoder to either the motor or spindle. But if the gearing is anything other than 1:1 you must get the index signal from the spindle. My gearing is 1:1.8 and the A/B encoder signals come from the motor side, but my Z (index) signal comes from the spindle side.

So i must attach encoder of encoder disk to spindle shaft because all other places
i can mount the encoder are not 1:1 gear ratio with spindle shaft.

To mechanically adjust the exact same ratio is very difficult
Also with counter chips division maybe can not be integer multiple
so the only real option is to mount and aluminum disk to spindle shaft
and because my spindle shaft from top has the hydraulic cylinder that locks the tool
the only place can put this is only to the downside of spindle shaft.
How many lines must have the disc for rigid tapping ?
Also must have disc with A B and Z signals or only A is enough ?

For rigid tapping i need only index signal from spindle shaft
A-B signals can come from elsewhere the encoder is mounted that is not 1:1 ratio correct ?

I have also some backlash to geartrain..
This will be problem for rigid tapping when tap goes backwards ?
If yes then must mount also encoder on spindle shaft..