7i76 encoder velocity

What does the 7i76 encoder velocity represent? I have a 1:1 encoder on my lathe spindle that has 2048 pulses per rev. So if the spindle is going at 1000rpm, what is the encoder velocity reading supposed to be?

If the encoder scale is correct (8192 for a 2048 PPR encoder),
the velocity is in RPS (or RPM on the velocity-rpm pin)

So if I see a velocity of 80 for about 1000 rpm it is not good? What can influence that output?

Is 80 the RPS or RPM pin?

Incorrect encoder scaling could be the issue

Is the encoder 2048 PPR (8192 counts per revolution in quadrature)
or 2048 counts per revolution?

That is the RPS reading. It's a quadrature encoder so I would imagine it is 2048 PPR.

If its a 2048 PPR the encoder, the scale should be 8192
If you were off by a factor of 4 like this then this would
80 RPS would become 20 RPS or 1200 RPM which is close.

I would watch the raw encoder counts and see how many
counts you get for 1 full turn (to set the encoder scale correctly)
 

Thanks Peter. That makes sense now. The scaling was out by a factor of 4.