Understanding G27, G28, G29 and G30: Take a closer look at these reference position commands

摘要

A few months ago I compared using the return to reference (zero return) position (G28) to the motion relative to the machine coordinate system command (G53). I received a few questions regarding other commands related to a machine's reference position, and I'd like to explain them here. In order to understand G27, G29 and G30, you must have a firm understanding of G28. This return to reference position is a two-step command. Indeed, if the single block switch is turned on, you must press the cycle start button twice to fully execute a G28 command.