BFS100 FLOW SWITCH is designed to operate with low viscosity, non-viscous or dirty liquids with moderate flow rates as water and water solutions, oil, and fuels. This model uses the well-know principle of thermal dispersion, based on the measurement of temperature difference deviation due to the flow rate via two temperature sensors immersed in the controlled medium. An output relay switches when the flow rate reaches the set-point value after maximum 15 sec. response time. An enhanced microcontroller design allows simple user calibration and continuous self-diagnostic. Local programmable indicator for process temperature is also available as an option.