| 摘要 |
<p>An electrical radiant heating body has two concentric heating zones with independently operable heating resistors. On only switching in the central zone, the associated heating resistor has a very high power which, on connecting in the outer zone, can be reduced by the connection in series of a heating resistor in the outer zone, so that there is a uniform heating surface loading for the total heating surface. The thermometer probe of a thermal cut-out projects over the heating surface and has two contacts operating at different temperatures, one of them being a changeover contact.</p> |
