What is a Global Origin?
The Global Origin defines the range of the X,Y,Z coordinates in the design file. The Global Origin is actually the lower left corner of the design plane (or cube for 3D files). The Global Origin command (GO=xxx,yyy,(zzz)) establishes the coordinate values at the global origin (the lower left corner). When you key in GO=$, the value given is the distance from the Global Origin (the lower left corner) to the coordinates XY=0,0.
The value of the Global Origin, combined with the file's working units settings, define the size of the file, the accuracy of the file, and the available coordinates.
The default global origin readout for Pipeline Drafting (GO=$) is
GO = -3737653.2644, -747482.9057