910 Datasheet, PDF (3/8 Pages) Magnetrol International, Inc. – ECHOTEL®CONTACTULTRASOUND

25+ Years of Ultrasonic Measurement Solutions for Industrial Process
Application Guidelines
makes them suitable for use in Safety Integrity Level
Over 25 years of experience with ultrasonic gap
switch technology has made the ECHOTEL
brand a world leader in liquid level switches.
Today’s line offers three distinct product offerings:
(SIL) 2 loops. Having either relay output or mA current
shift capability, Models 961/962 can be used for more
process applications, making them the most universal
liquid level switches available today.
• For applications where self-test isn’t
required, our economical Model 910 with
continuous wave technology is a reliable switch
with a tip-sensitive transducer.
910
• Though OEM priced, our compact Models
940/941 offer both advanced tip-sensitive
transducers and pulsed signal technology.
• Single Point Model 961 and Dual Point
Model 962 offer tip-sensitive transducers, pulsed
signal technology, advanced self-test and a time
delay feature.
940/941
Models 961/962 represent the pinnacle of
ultrasonic switch development at Magnetrol^®.
Their continuous self-testing of electronics,
transducer, piezoelectric crystals, and testing
Advantages and Limitations
The advantages of contact level sensing using
ultrasonic technologies are:
• Low cost single and dual point sensing.
• Accurate and reliable in a wide variety of liquids.
• Unlike tuning forks, no density adjustments required.
• Easy installation and simple configuration.
• A broad range of available sensor materials.
• Transmits a stable signal despite liquid property
changes in specific gravity, conductivity, pH, and
dielectric or temperature shifts.
• Switches are 100% electronic and
% ^ELECTRO
contain no moving parts which can
degrade or require high maintenance.
MOVING P
for electromagnetic noise, alarms the user of a
malfunction or the presence of EMI/RFI noise. ⁹⁶¹
An adjustable time delay of 0.5 to 45 seconds helps
curtail nuisance alarms and relay chattering.
With extensive FM, CSA, and ATEX approvals
the Models 961/962 are suitable for virtually any
hazardous location. Their SFF* value of over 90%
Certain process conditions may interfere with the
ultrasonic signal. These conditions include:
• Slurries with a very high percentage of solids.
• Extreme aeration of the liquid.
• Liquids which generate crystallized coatings.
• Very aggressive turbulence and splashing.
At a Glance:
Contact Ultrasonic Switches
Model
910
940
941
961
962
Ultrasonic Technology
Continuous Wave
Pulsed Signal
Pulsed Signal
Pulsed Signal
Pulsed Signal
Set Points
Output
Mounting
SIL Loop 3-A Self-Test Time Delay
Single
Relay
Integral
N.A.
Single
Relay
Integral
2
Single Current Shift (CS) Integral
1
Single
Relay or CS Integral or Remote
2
I
I
I
Dual
Relay or CS Integral or Remote
2
I
I
*In the language of Safety Instrumented Systems (SIS), Safe Failure Fraction (SFF) indicates all safe and dangerous detected failures. The
Models 940 and 961/962 SFF values are over 90%, which allows them to be used in SIL 2 loops.
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