The RESOL V40 is a measuring instrument with a contactor for detecting the flow of water or water-glycol-mixtures and is used with the RESOL calorimeter. It is ready for use in the RESOL calorimeters. After a specific volume has passed, the V40 reed switch sends an impulse to the calorimeter. The heat quantity used is calculated by these impulses, the temperature difference and pre-defined parameters (glycol type, concentration, heat capacity etc.). Delivery includes connecting screw.