Ceramic glass hot plate with temp. sensor - has warning lamp and bimetallic spiral in chamber in cover plate actuating switch contacts

摘要

A ceramic glass hotplate has a sensor to indicate the temp. on the surface of the plate. The temp. sensor operates a contact for a signalling device to prevent accidents. The temp. indicator consists of an insulated body with a spiral bi-metallic strip (25). The insulating body is incorporated in the cover plate (14) in the heating unit in the form of a disc with the bi-metallic spiral on one side, parallel to the surface of the disc. It fits into a hole (19) in the cover plate to form an enclosed space (22). There is also an indicator lamp, switched on by a pair of contacts actuated by the bimetallic spiral. The temp. sensor and the indicator lamp are connected in parallel and are supplied via a dropper resistor.