| 摘要 |
<p>Electrically heated instantaneous heater having a device for determining the throughput of water with heating resistances in a passage duct, in which, in order to determine the water inlet and water outlet temperatures, a temperature sensor is provided upstream and downstream of these resistances, the throughput being calculated in accordance with the equation DR = PM/(c.(TA - TE)), according to which PM is the output of the heating resistance in kW, c is the specific heat capacity of the water in kWh/kg, TA and TE are the outlet and inlet temperatures in degree C, characterized in that that portion of the passage duct which is located between the two temperature sensors is equipped as a measurement section with two component resistances 7, 8, one of the component resistances 7 being connected to a switch 11, in order to switch off this component resistance 7 at small throughput amounts. <IMAGE></p> |
