Echotel® 961 and 962 Series Single-Point and Dual-Point Ultrasonic Level Switches

Product Description:

The ECHOTEL Model 961 provides the ultimate solution for reliable single-point level measurement. This advanced switch utilizes pulsed signal technology, offering excellent performance under challenging process conditions and strong resistance to electromagnetic interference. Extensive self-diagnostic technology for both electronic components and sensors makes this advanced switch suitable for sa...

Applications:

Chemical, crude oil processing, natural gas processing, nuclear power, power generation, petroleum refining

Features:

(1) No calibration required;

(2) Loop current or relay output;

(3) Advanced self-diagnostics: sensor, electronic components, and electrical noise interference;

(4) LED indicator for displaying status and errors;

(5) Push-button for manual output testing;

(6) Metal and plastic sensors;

(7) Adjustable delay for fluctuating or aerated liquid levels;

(8) Pulsed signal technology;

(9) FM, CSA, and ATEX explosion-proof and intrinsically safe certifications;

(10) Suitable for Safety Integrity Level (SIL) 2 loops.

Working Principle:

(1) The Model 961/962 switch utilizes ultrasonic energy to detect the presence or absence of liquid at single or dual points in the sensor. Ultrasonic contact level technology uses high-frequency sound waves that easily propagate across the sensor gap when liquid is present but attenuate when the gap is dry. The Model 961/962 switch employs a 2 MHz ultrasonic frequency for level measurement across various process media and application conditions.

(2) The sensor uses a pair of piezoelectric crystals encapsulated in epoxy at the sensor tip. The crystals are made of ceramic material that vibrates at a given frequency when voltage is applied. The transmitting crystal converts the voltage signal from the electronics into an ultrasonic signal. When liquid is present in the gap, the receiving crystal senses the ultrasonic signal from the transmitting crystal and converts it back into an electrical signal. This signal is sent to the electronics to indicate the presence of liquid in the sensor gap. When no liquid is present, the ultrasonic signal attenuates and cannot be detected by the receiving crystal.