| 摘要 |
<p>A control circuit for an electrical resistance storage system includes a solid state switch such as a triac (32) which controls the power supply to a heating element (30). The triac (32) is controlled by a driver circuit (34) in response to the output of a pulse generator (36) and a zero-crossing detector (38). The circuit (34) is controlled by an inhibit circuit (54) and an I.C. (46) including a comparator (50) adapted to compare the output signal from a thermocouple (44) with a preset reference and to control the driver circuit (34) and thus the triac (32) on the basis of the comparison. The thermocouple (44) senses the temperature of a refractory mass heated by the element (3). The power supply (40) for the circuits (34 and 46) is preferably provided by the mains supply powering the heating element (30). <IMAGE></p> |
