Check assigned programme zero to fixture offset Video
 
Work offsets are data registers in the CNC control that hold the distance from the machine home X, Y, Z position to the part datum. These offsets can be thought of like a table on the control:
 

The X and Y values represent the distance from the machine home to part datum XY. The Z value is the distance from the tool reference point (for example, the top of a 1-2-3 block) and the part Z-datum.
 
An example in code:

G54 X0. Y0

 

 
Additional info
Additional info