The paper deals with didactic model of water tank, which is controlled via using of microcontroller as embedded system or other control system. System consists of water tank, water level sensor, water pump, transistor-relay module and control system. The aim is to use function model of system for practical exercises on mechatronic courses for bachelor and master students. Students have to complete system, make a testing of all components, make a hardware completed structure and make a software for microcontroller.