The load weighing unit LUPO with an external load sensor controls and shows the load of a lift car and it meets the requirements of EN81 (126.96.36.199 and 188.8.131.52). The unit has three floating relays for switching minimum load, full load and over load. LUPO can be used for all types of lifts. The installation and the setting-up operation of LUPO are very simple and need only short time. No additional measuring tool is needed. The unit is state-of-the-art with improved and up-to-date electronic. The electronic is built in a plastic housing (IP54).