1. introduction rlb thermal meter is a kind of instrument used to measure and display the released heat power when the heat-carrying liquid pass through the heat exchange system. rlb thermal meter is consisted of flow sensor, microprocessor and matched pair temperature sensor. the microprocessor gets the flow signal through flow sensor and the signal of water temperature at the entrance and exit from the temperature measuring circuit, then calculates released heat by the heat-carrying liquid according to the standard heat calculation formula. the meter is designed and developed on the basis of the european standard en1434 and 01ml-r75 international standard, and has high performance and low energy consumption, and in line with the product standard cj128-2000 thermal meter issued by state construction department of china. the thermal meter also can be used as an instrument which measure cold power if connect reversely the temperature sensors. 2. functions * the flow measurement adopts the latest patent technology of wireless digital monitoring. * the flow measurement adopts no mechanic gears, non-magnetic sensor, wear-proof, anti-corrosive and anti-attack. * low voltage and alarms when being attacked. * alarms when the temperature sensor is disconnected or has a short cut. * flow and temperature has 10 levels and are separately adjusted, with high precision. * intelligent reduction of consumption according to the rate of flow. * the program can be upgraded online. * multi data backup and automatic-correction technology. * ultra-low energy consumption. 3. two kinds of working conditions of thermal meter our thermal meter has two kinds of working states, which are testing state and normal working state. the measure accuracy of testing state is higher than normal working state. for example, the minimum measure parameter of testing state is 0. 001 kwh, but under normal working state, the parameter will be 1kwh.