Start with the elevators near the floor (bails floated). Slowly raise the blocks until you have reached the first layer change (cable has reached the end of the drum). Take a measurement from the bottom of the elevators down to the floor. This could be a small number. Press SELECT, highlight SETUP press SELECT, highlight HEIGHT RE-CAL press SELECT. Press SELECT on RESET TO 1ST LAYER CHG. Use arrow to enter measurement and press ACCEPT twice to save.