Echotel
®
Models 344/345
Ultrasonic Non-Contact
Transmitters for Level,
Volume, or Open Channel Flow
D E S C R I P T I O N
Echotel
®
Models 344 and 345 are full-featured, ultrasonic
non-contact transmitters that provide continuous mea-
surement for liquid level, volume, or open channel flow
applications. These versatile transmitters utilize the
latest in microprocessor-based electronics along with
powerful non-contact ultrasonic transducers, to provide
level measurement that is not affected by changes in
specific gravity, viscosity, or conductivity.
Model 344 and 345 are remote mounted transmitters
that feature a front panel keypad, and a large
16-character alphanumeric display of all parameters.
These transmitters are paired up with Kynar
®
and
316 stainless steel EchoMaster
™
Ultrasonic Transducers
that have extensive agency approvals for hazardous
area locations.
F E A T U R E S
•
Front panel keypad for ease of programming – no
need to open enclosure after wiring
•
4–20 mA isolated (1,000
Ω
load) and RS-232 outputs
•
Four 10 amp SPDT relays allow for simple alarm
configurations to complex pump control including
lead/lag alternation of pumps
•
Password code prevents unauthorized tampering of
calibration parameters
•
16-character alphanumeric display of all parameters.
•
Water and wastewater
•
Complete self-diagnostics assures unit is operating
properly by checking all relays, outputs, and system
functionality
•
Temperature compensation integral to all ultrasonic
transducers
•
False target buffering eliminates signal interference
from fixed obstructions in vessel
•
Slurries
•
Viscous fluids
•
Fuel oils
•
Acids
•
Caustics
A P P L I C A T I O N S
T E C H N O L O G Y
Model 344 and 345 systems consists of three main com-
ponents: an ultrasonic transducer, a transmitter, and an
interconnecting cable package.
The transducer contains a piezoelectric crystal that con-
verts electrical signals generated by the transmitter into
ultrasonic pulses. These pulses, or sound waves, are
directed through the air toward the liquid surface. They
are then reflected off the liquid surface as an echo, and
returned to the transducer. The piezoelectric crystal then
converts the returned echo into an electrical signal which
is analyzed by the transmitter. The elapsed time between
the generation of the ultrasonic pulse and the return echo
is proportional to the distance between the face of the
transducer and the liquid surface. The distance value is
used by the transmitter to compute level, volume, or flow
in the engineering units selected by the user.
E C H O M A S T E R
T R A N S D U C E R
50 kHz Model 385 transducer that is available in either
Kynar or 316 stainless steel. The higher frequency 50 kHz
transducer makes the 345 well suited for open channel
flow, and shorter range applications.
EchoMaster transducers are available in a wide variety of
configurations to accommodate a broad range of industri-
al and municipal applications. The 344 uses the powerful
38 kHz Model 384 Kynar transducer, and is primarily used
for level and volume applications. The 345 uses the
Model 384
Model 385
Operating
Frequency
38 kHz
50 kHz
Material
Kynar
Kynar or 316 SS
Insertion
Lengths
3" & 10"
3", 6", & 10"
NPT Process
Connection
1" or 2"
3
⁄
4
" or 2"
Housing
none, aluminum, or
316 stainless steel
T Y P I C A L
M O U N T I N G
C O N F I G U R A T I O N S
maximum level attainable. This dead band distance is
18 inches (460 mm) for the Model 384 transducer, and
12 inches (305 mm) for the Model 385 transducer.
In Figure 1, the transducer is installed above the liquid
surface, and the transmitter is mounted as far as 500 feet
(152 meters) away. A minimum dead band distance must
be allowed between the face of the transducer and the
Transducer
Dead Band
Air
Model 345
25
feet
(7.6 m)
maximum
Range
Model 344
35
feet
(10.7 m)
maximum
Span
Liquid
Maximum Model 345: 24
feet
(7.3 m)
Model 344: 33.5
feet
(10.2 m)
Minimum Model 344: 18
inches
(460 mm)
Model 345: 12
inches
(305 mm)
Figure 1
Typical Transducer Mounting – Level/Volume
2
T Y P I C A L
M O U N T I N G
C O N F I G U R A T I O N S
of the vessel. This helps to keep the 12 degree ultrasonic
beam away from pumps, ladders, side walls, or other
obstructions in the vessel.
Figure 2 shows a typical transducer mounting on a brack-
et for open channel flow measurement. Figure 3 shows
how the transducer can often be mounted further down in
a wet well or sump if the liquid will never reach the top
Electronics
Transducer
Flow
Parshall
Flume
Figure 2
Typical Transducer Mounting – Open Channel Flow
Figure 3
Typical Transducer Mounting – Wet Well or Sump
U L T R A S O N I C
B E A M
A N G L E
liquid surface. The chart below shows the distance the
transducer should be located away from side walls and
obstructions. The distances are based on a 6° beam radius
at different heights above the liquid surface. Generally
speaking, the transducer should be mounted one foot
away for every 10 feet of height.
A 12° conical beam of ultrasonic energy is emitted from
the face of the transducer. The transducer should be
mounted in a location such that the ultrasonic signal does
not touch the side walls or any other obstructions in the
vessel. This is typically accomplished by using a bracket,
half-coupling, or rigid conduit to mount the transducer in
a spot where a strong echo can be received off of the
Distance from
Transducer Face (feet)
3'
6'
9'
12'
15'
18'
21'
24'
27'
30'
33'
12° Beam
Diameter (feet)
0.6'
1.3'
1.9'
2.5'
3.2'
3.8'
4.4'
5.0'
5.7'
6.3'
6.9'
Minimum Distance from
Wall or Obstruction (inches)
4"
8"
11"
15"
19"
23"
26"
30"
34"
38"
42"
3
F A L S E
T A R G E T
D E T E C T I O N
When it is impossible to mount the transducer far
enough away from obstructions in the vessel a unique
false target detection feature can be used. This target
detection mode programs the transducer to search for,
and display, the distance of the target nearest the trans-
ducer. When this false target is detected, the level infor-
mation of this unwanted target is stored in the buffer for
false targets. This process is repeated until all of the pos-
sible false target locations are programmed into the
transmitter or the buffer is full. A maximum of nine false
targets can be programmed into the buffer.
Successful configuration of false targets will eliminate the
possibility of unwanted target echoes being recognized
as the real material level in the vessel. This technique is
applicable to any obstruction which remains at the same
horizontal plane (i.e., ladder rungs, pipes, tank braces,
mixer blades, etc.) in the vessel.
T R A N S M I T T E R
Supply voltage
S P E C I F I C A T I O N S
120 VAC +10%/-15%, 50–60 Hz
240 VAC +10%/-15%, 50–60 Hz
24 VDC, ±20%
Power consumption
Fuse size
Output signal
Relays
Fail-safe
Display
Keypad
Enclosure material
Response time
Accuracy
Humidity
Ambient temperature
without heater & thermostat*
with heater & thermostat
12 watts (without heater)
1
⁄
4
amp replaceable, 250 VAC Slo-Blo
®
for AC units
2 amp replaceable, 250 VDC Slo-Blo for DC units
4–20 mA isolated (1,000
Ω
load), RS-232
Four 10 amp resistive, SPDT
User selectable for analog and relay outputs
Sixteen (16) character alphanumeric LCD
Sixteen (16) button integral to front panel
High-impact polycarbonate
2 seconds typical
± 0.25% of calibrated span
95% Non-condensing
-4° to +160° F (-20° to +70° C)
-40° to +160° F (-40° to +70° C)
* NOTE: The 31-day data logger has a +32° F (0° C) minimum when used without the heater and thermostat.
4
T R A N S D U C E R
S P E C I F I C A T I O N S
Model 384
Model 385
50 kHz
25 feet (7.6 meters)
24 feet (7.3 meters)
12 inches (305 mm) from
-40° to + 140° F (-40° to +60° C)
18 inches (460 mm) from
+140° to +200° F (+60° to +93° C)
Transducer frequency
Maximum range
Maximum span
Minimum dead band
38 kHz
35 feet (10.7 meters)
33.5 feet (10.2 meters)
18 inches (460 mm) from
-40° to +163° F (-40° to +73° C)
Operating temperature
Operating pressure
Temperature compensation
Beam angle
Cable length
-40° to +163° F (-40° to +73° C)
-40° to +200° F (-40° to +93° C)
-10 to +50 psig (-0.69 to +3.45 bar)
Automatic over the operating temperature range of the transducer
12° conical
500 feet (152 meters) maximum between transducer and transmitter
A G E N C Y
AGENCY
A P P R O V A L S
APPROVAL CATEGORY
APPROVAL CLASSES
MODEL APPROVED
FM
34X-X442-10X
Non-hazardous
Non-incendive
NEMA 4X, IP65
Class
I, II, III,
Div. 2;
Groups A, B, C, D, F, & G, T4A
NEMA 4X, IP65
Class
I, II, III,
Div. 1;
Groups B, C, D, E, F, & G, T6
NEMA 4X, IP65
Class
I, II, III,
Div. 1;
Groups B, C, D, E, F, & G, T6
Class
I, II, III,
Div. 1;
Groups A, B, C, D, E, F, & G, T6
Type 4X enclosure
Class
I, II, III,
Div. 2;
Groups A, B, C, D, E, F, & G, T4A
Type 4X enclosure
Class
I, II, III,
Div. 1;
Groups B, C, D, E, F, & G
Class
I, II, III,
Div. 1;
Groups C, D, E, F, & G
Type 4X enclosure
Class
I, II, III,
Div. 1;
Groups C, D, E, F, & G
Class
I, II, III,
Div. 1;
Groups A, B, C, D, E, F, & G
Class
I, II, III,
Div. 2;
Groups A, B, C, D, E, F, & G
384-XKXX-0XX
Non-hazardous
Explosion proof
385-XXXX-XXX
385-XEXX-006
385-XEXX-010
385-XEXX-003
CSA
34X-X442-10X
344-X442-10X
384-XKXX-0XX
384-XK0X-0XX
384-XK1X-0XX
384-XKYX-0XX
385-XXXX-XXX
385-XE1X-0XX
385-XEYX-0XX
385-XE0X-0XX
385-XX1X-XXX
Non-hazardous
Explosion proof
Explosion proof
Non-hazardous
Non-incendive
Non-hazardous
Explosion proof
Explosion proof
Non-hazardous
Explosion proof
Explosion proof
Non-incendive
5
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