摘要 |
<p>The present invention refers to a device (1) for cleaning fluid from contaminating matter, which device comprises a vessel (11) for fluid, a heating element (12) for heating fluid, control electronics (13) to control the heating element (12), and also a temperature sensor (14) for measuring the temperature of the fluid. The control electronics (13) is adapted to lower the heating capacity of the heating element (12) when the fluid has reached a predetermined temperature according to temperature sensor (14) and thereafter let the fluid be heated by a lower effect during a predetermined time period according to a time measuring unit (15) belonging to the device. This time measuring unit (15) comprises a frequency counting unit (15a), adapted to count periods in the supply current (16) input to the device (1). The time measuring unit (15) indicates to the control electronics (13) that the time period has elapsed when the number of counted periods corresponds to the time period in seconds times the frequency for the incoming supply current (16).</p> |