Ultrasonic level switch Echotel® 961

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Increasing demands for compliance with safety systems and overfill protection have mandated more reliable point level measurement. Echotel® Models 961 and 962 ultrasonic level switches meet these demands with advanced transducer designs, extensive hazardous location approvals, and a new self-test technology. Single Point ECHOTEL Model 961 offers the ultimate solution to reliable single-point liquid level measurement. This advanced switch uses pulsed signal technology for superior performance in difficult process conditions, and to provide excellent immunity from sources of electrical noise interference. Extensive self-testing of the electronics and transducer make this advanced switch suitable for use in Safety Integrity Level (SIL) 2 loops. The ECHOTEL Model 961 is equipped with advanced diagnostics that continuously check the sensor and electronics. The diagnostics also alarm for electrical noise interference from external sources. Dual Point ECHOTEL Model 962 is a dual-point switch that can be used as a level controller, or to control pumps in an auto fill or auto empty mode. The tip sensitive lower gap performs well in aerated or foamy liquids, and can measure to within 1.4" of the vessel bottom. The rigidity of the unique flow-through upper gap allows separations of up to 125" (318 cm) between the upper and lower transducer gaps. Ultrasonic contact switches use a pair of piezoelectric crystals that are encapsulated in epoxy at the tip of the transducer for level measurement. The crystals are made of a ceramic material that vibrates at a given frequency when subjected to an applied voltage. The transmit crystal converts the applied