| 摘要 |
<p>A waterboiler includes 2 kW and 1 kW heating elements (11,12 respectively) that together heat the water (2) to about 96 deg. C, as sensed by a thermistor (14). The 2 kW element (11) cuts out and the water is further heated, to and maintained at, boiling point by the kW element (12). In an alternative, the output of a single heating element is modulated by using a transformer to reduce the voltage input. A water inlet has a solenoid valve controlled by a reed switch actuated by a magnetic float. Another reed switch magnetic float ensures that the heating elements cannot be energised until they are immersed.</p> |
