Invitation was made to vacate the Luopan and it duly follows suit. There is a numb sensation when it moves away from the Luopan and at a blink, it functions as normal. From the earth it comes, to the earth it must return. That is the principle.
So, Luopan is NEVER an ordinary tool, as suggested and advocated by the academy in town. If the designer do not even understand the differentiation between the red and the black, let alone, arranging the rings of the Luopan, how well would he practices the art and be protected by the art? So, next time if any practitioner happened to measure the door of another dimension, who do you call, 911 or the ghost buster?