Liq. level detector and controller - uses coaxial probe operating on change of inductance or capacitance principle

摘要

The electronic level regulator and detector operates, via an inductive initiator, to energise a contractor or magnetic valve controlling the level of liq. in a vessel. The detector probe comprises an outer insulating tube of ceramic material which is screwed into the wall of the vessel so that the tube is in contact with the contents of the reservoir. A central conducting electrode within the insulating tube is connected to the inductive circuit of the primary side of an initiator. The earthed side of the vessel is connected to the second terminal of the circuit. Through variation of the inductance or capacitance due to a change in liq. level, the initiator oscillating circuit is unbalanced and a signal produced to operate the control circuit or magnetic valve.