What is the meaning of 1000 LU/MIN in RPM IS?

Hello,

LU is a free adjustable unit that you can set to whatever you want. 

In the setting for "LU per load revolution" in your mechanics you define how much your position increases (in software) by one load revolution. And so you define the positioning resolution and your own unit (e.g. 1 LU = 1 mm or 0.001 inch or whatever you want).

First example: e.g. you have a linear axis with spindle pitch of 10mm you could set it to 10 000 LU per load revolution. Then your resolution for positioning is 1LU = 1µm. 

And so the real velocity's unit would be [1000 µm/min].

Second example for round axis: you set LU per load revolution to 360 000 LU, then your positioning resolution is 1LU = 1 milli degree. Then the real velocity is [1000 m°/min]. 

When you want a speed of e.g. 10 rpm you calculate:

speed [1000 LU/min] = (LU per load revolution * speed [rpm]) / 1000 = 360 000 LU * 10 rpm / 1000 =  3 600 [1000 LU/min] 

Hope this helps to understand the LUs ;)