English: heat meter is calculated, working principle: a pair of temperature sensors are mounted on a heat transfer fluid through the pipe upstream and downstream pipe, flow meters are installed on the fluid inlet or return pipe (flow meter installed at different locations, and the final measurement results different), the meter emits a pulse signal proportional to the flow, given a temperature sensor indicates the temperature level of the analog signal, and Totalizer acquired signals from the flow and temperature sensor, use the calculator formula for calculating the heat exchange system obtained heat.