Echotel 961/962 single- and dual-point ultrasonic level switches

Downloads

Echotel® 961/962 single- and dual-point ultrasonic level switches

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

Technology

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 voltage from the electronics into an ultrasonic signal. When liquid is present in the gap, the receive crystal senses the ultrasonic signal from the transmit crystal and converts it back to an electrical signal.

No calibration
Loop current or relay output
Advanced diagnostics: sensor, electronics and electrical noise interference
LED indication for alarm status and error
Pushbuttons for manual testing of output
Metal and plastic sensors
Adjustable time delay for turbulent aerated liquids
Pulsed signal technology
Extensive FM, CSA and ATEX explosion proof and intrinsically safe approvals
Suitable for Safety Integrity Level (SIL) 2 loops

Options

Relay output or mA current shift with separate malfunction indication
Integral or remote mount
Glass window housing cover
Cast aluminum, cast stainless steel or deep drawn stainless steel housings
Transducer materials of 316/316L stainless steel, Hastelloy, Monel, Kynar, CPVC or 316/316L SS with 20 Ra sanitary finish
ASME B31.1, ASME B31.3 and NACE construction

Chemical

Blending operations
Chemical injection
Chemical injection skids
Chemical reactors
Chlor-alkali process
Deionization tanks
Mixing & blending systems
Neutralization
Scrubber vessels
Seal pots – liquid level measurement

Common applications

Level: Containment & drainage sumps
Level: Lubrication oils & hydraulic fluids
Level: Process & field storage tanks
Level: Seal Pots
Level: Water storage & wash tanks

Crude oil

Chemical injection
Process & Field storage tanks
Vapor recovery unit

Natural gas

Chemical injection
Chemical injection skids
Compressor Scrubber
Compressor Waste Liquid
Flare Knock-out Drum
Gas Dehydration
NGL recovery & Storage
Separators
Sour gas treatment
Sulfur Recovery
Vapor recovery unit

Nuclear power

Cooling tower basins
Cooling tower intake & basin levels

Petroleum refining

Alkylation tanks
Blending operations
Diesel fuel storage tanks
Refinery flow applications

Power generation

Condensate receiver tanks
Cooling tower basins
Cooling tower intake & basin levels
Deionization tanks

Pulp & paper

Chlorine Dioxide Generators
Condensate receiver tanks
Digester blow tanks
Mill water storage
Mixing & machine chests
Source water & bar screens
Turpentine Recovery

Renewable energy

Biofuel
Biogas
Geothermal
Hydroelectric
Wind

Water & wastewater

Carbon slurry level

Model 961/962 switches utilize ultrasonic energy to detect the presence or absence of liquid in a single or dual point transducer. Ultrasonic contact level technology uses high-frequency sound waves that are easily transmitted across a transducer gap in the presence of a liquid media, but are attenuated when the gap is dry. Model 961/962 switches use an ultrasonic frequency of 2 MHz to perform this liquid level measurement in a wide variety of process media and application conditions.

The transducer uses a pair of piezoelectric crystals that are encapsulated in epoxy at the tip of the transducer. 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 voltage from the electronics into an ultrasonic signal. When liquid is present in the gap, the receive crystal senses the ultrasonic signal from the transmit crystal and converts it back to an electrical signal. This signal is sent to the electronics to indicate the presence of liquid in the transducer gap. When there is no liquid present, the ultrasonic signal is attenuated and is not detected by the receive crystal.

ATEX	Ex d, Ex ia
CCOE	Ex d, Ex ia
CSA	XP, IS, NI
FM	XP, IS, NI
EAC (GOST)	Ex d, Ex ia
IEC	Ex d
Inmetro	Ex d, Ex ia
SIL	SIL 2 (1oo1)
TÜV/DIBt	WHG § 63, overfill prevention

Other approvals are available.

Features

No calibration
Loop current or relay output
Advanced diagnostics: sensor, electronics and electrical noise interference
LED indication for alarm status and error
Pushbuttons for manual testing of output
Metal and plastic sensors
Adjustable time delay for turbulent aerated liquids
Pulsed signal technology
Extensive FM, CSA and ATEX explosion proof and intrinsically safe approvals
Suitable for Safety Integrity Level (SIL) 2 loops