Warranty, Service & Repair
WARRANTY
Flowline warrants to the original purchaser of its products that such
products will be free from defects in material and workmanship under
normal use and service for a period which is equal to the shorter of
one year from the date of purchase of such products or two years from
the date of manufacture of such products.
This warranty covers only those components of the products which
are non-moving and not subject to normal wear. Moreover, products
which are modified or altered, and electrical cables which are cut to
length during installation are not covered by this warranty.
Flowline’s obligation under this warranty is solely and exclusively
limited to the repair or replacement, at Flowline’s option, of the products (or components thereof) which Flowline’s examination proves to
its satisfaction to be defective. FLOWLINE SHALL HAVE NO
OBLIGATION FOR CONSEQUENTIAL DAMAGES TO PERSONAL OR REAL PROPERTY, OR FOR INJURYTO ANY PERSON.
This warranty does not apply to products which have been subject to
electrical or chemical damage due to improper use, accident, negligence, abuse or misuse. Abuse shall be assumed when indicated by
electrical damage to relays, reed switches or other components. The
warranty does not apply to products which are damaged during shipment back to Flowline’s factory or designated service center or are
returned without the original casing on the products. Moreover, this
warranty becomes immediately null and void if anyone other than service personnel authorized by Flowline attempts to repair the defective
products.
Products which are thought to be defective must be shipped prepaid
and insured to Flowline’s factory or a designated service center (the
identity and address of which will be provided upon request) within
30 days of the discovery of the defect. Such defective products must
be accompanied by proof of the date of purchase.
Flowline further reserves the right to unilaterally wave this warranty
and to dispose of any product returned to Flowline where:
a. There is evidence of a potentially hazardous material present
with product.
b. The product has remained unclaimed at Flowline for longer than
30 days after dutifully requesting disposition of the product.
THERE ARE NO WARRANTIES WHICH EXTEND BEYOND
THE DESCRIPTION ON THE FACE OF THIS WARRANTY. This
warranty and the obligations and liabilities of Flowline under it are
exclusive and instead of, and the original purchaser hereby waives, all
other remedies, warranties, guarantees or liabilities, express or
implied. EXCLUDED FROM THIS WARRANTY IS THE IMPLIED
WARRANTY OF FITNESS OF THE PRODUCTS FOR A PARTICULAR PURPOSE OR USE AND THE IMPLIED WARRANTY OF
MERCHANT ABILITY OF THE PRODUCTS.
This warranty may not be extended, altered or varied except by a written instrument signed by a duly-authorized officer of Flowline, Inc.
To register your product with the manufacturer , fill out the enclosed
warranty card and return it immediately to:
Flowline Inc.
10500 Humbolt Street
Los Alamitos, CA 90720.
If for some reason your product must be returned for factory service,
contact Flowline Inc. to receive a Material Return Authorization
number (MRA) first, providing the following information:
1. Part Number, Serial Number
2. Name and telephone number of someone who can answer
technical questions related to the product and its application.
3. Return Shipping Address
4. Brief Description of the Symptom
5. Brief Description of the Application
Once you have received a Material Return Authorization number,
ship the product prepaid in its original packing to:
Flowline Factory Service
MRA _____
10500 Humbolt Street
Los Alamitos, CA 90720
To avoid delays in processing your repair, write the MRA on the
shipping label. Please include the information about the malfunction with your product. This information enables our service technicians to process your repair order as quickly as possible.
®
Version 3.1A
© 1999 FLOWLINE Inc.
All rights reserved.
Manual # LU900005 11/99
Ultrasonic Level Transmitter
Model LU20
Owner’s Manual
NRTL/C
Step One
SPECIFICATIONS
Range: 0.5 to 18 feet (15 cm to 5.4 m)
Accuracy: ± 0.25% of span in air
Resolution: 0.125” (3 mm)
Frequency: 50 kHz
Pulse rate: 2 pulses per second
Beam width: 8° conical
Deadband: 0.5’ (15 cm) minimum
Blocking distance: 0.5 to 18 feet (15 cm to 5.4 m)
Display type: 4 segment LCD
Display units: Inch (cm)
Memory: Non-volatile
Supply voltage: GP: 12-36 VDC
IS: 12-32 VDC
Max loop resistance GP: 900 Ohms @ 36 VDC (see below)
IS: 900 Ohms @ 32 VDC (see below)
Signal output: GP: 4-20 mA, 12-36 VDC (see below)
IS: 4-20 mA, 12-32 VDC (see below)
Signal invert: 4-20 mA/ 20-4 mA
Calibration: Push button
Fail-safe diagnostics: Reverts to 4 mA, 22 mA or remains constant
Temperature rating: F: -40º to 140º C: -40º to 60º (see below)
Temp. compensation: Automatic over entire range
Pressure rating: 30 psi (2 bar) @ 25 °C., derated @ 1.667 psi
(.113 bar) per °C. above 25 °C. (see below)
Enclosure rating: NEMA 4X (IP65)
Enclosure material: Polypropylene (PP), U.L. 94VO
Transducer material: Polyvinylidene Fluoride (PVDF)
Mounting threads: 2” NPT (2” G)
Mounting gasket: Viton (2”) metric only
Conduit connection: 1/2” NPT (1/2” BSP)
CE Compliance: EN 50082-2 immunity
EN 55011 emission
CSA Certificate: LR79326-10
*GP = General Purpose IS Intrinsically Safe
Technology
An ultrasonic sound wave is pulsed two
times per second from the base of the
transducer. The sound wave reflects
against the process medium below and
returns to the transducer. The microprocessor based electronics measure
the time of flight between the sound
generation and receipt, and translates
this figure into the distance between the
transmitter and process medium below.
Warning
The LU20 is a loop powered device. The load should never
exceed 900 Ohms.
LU20-50_1-IS must be installed in accordance with drawing
LU20CD rev B (see steps) for safe operation in a hazardous
area.
When installing the LU20, never tighten the transmitter from
the body. Always use the wrench flat located above the
threads.
Always install the 2” Viton gasket with the LU20-5061 and
the LU20-5061-IS. The G threaded version of the Echotouch
will not seal unless the gasket is installed properly.
NON-HAZARDOUS LOCATION
Control drawing for the LU20-5001-IS ultrasonic level transmitter
approved under the entity concept as an I.S. apparatus
Control Drawing: LU20CD
Rev. 7-24-97
Model LU20
Ultrasonic
Level Transmitter
Vmax = 32.0 V
Imax = 130 mA
Ci ≈ 0 µF
Li ≈ 0 µH
Any Approved
I.S. Barrier
Vdc ≤ 32.0 V
Isc ≤ 130 mA
Ca ≥ 0 µF
La ≥ 0 µH
Supply
HAZARDOUS LOCATION
Class I, Div I, Groups A, B, C & D
LR79326-10
NRTL/C
®
Intrinsically Safe/
Securite Intrinseque
Exia
For use in
Hazardous Locations:
Class I, Groups A, B, C & D
Class II, Groups E, F & G
Class III
Temperature Code: T3C
Intrinsically Safe when used with
an approved I.S. barrier. Entity
Parameters
Vmax = 32.0 VDC
Imax = 130 mA
Ci = 0 µF
Li = 0 µH
Warning: Suitable for Class I, Groups A, B,
C & D; Class II, Groups E, F & G; Class III,
T3C; when used with an approved I.S.
barrier. Substitution of components may
impair intrinsic safety LU20-50X1-IS
requirements for Intrinsically Safe
operation
Temperature/Pressure Derating
35
30
25
20
15
10
05
00
-40 -20 00 20 40 60
Operating Pressure (psi)
Temperature (°C)
Unacceptable
Range
Acceptable
Range
Maximum Temperature/Voltage Derating
Continuous 20 mA Curve (LU20-50_1)
100
80
60
40
20
0
Operating Voltage (VDC)
Ambient Sensor Temperature (°C)
Unacceptable
Range
Acceptable
Range
12 16 20 24 28 32 36
1,000
750
500
250
0
Max. Series Resistance (Ohms)
12 16 20 24 28 32 36
Unacceptable
Range
Acceptable
Range
Flowline 4 or 20 mA
LU20-50_1 Electrical Loading Limits
Maximum Temperature/Voltage Derating
Continuous 20 mA Curve (LU20-50_1-IS)
100
80
60
40
20
0
12 16 20 24 28 32 36
Operating Voltage (VDC)
Ambient Sensor Temperature (°C)
Unacceptable
Range
Acceptable
Range
1,000
750
500
250
0
Max. Series Resistance (Ohms)
12 16 20 24 28 32
Supply Volyage (VDC)
Unacceptable
Range
Acceptable
Range
Flowline 4 or 20 mA
LU20-50_1-IS Electrical Loading Limits
Part# Description Thread
LU20-5001 General Purpose 2” NPT
LU20-5061 General Purpose 2” G
LU20-5001-IS Intrinsically Safe 2” NPT
LU20-5061-IS Intrinsically Safe 2” G
Step Two Step Three
SAFETY PRECAUTIONS DEFINITIONS
About this Manual:
PLEASE READ THE ENTIRE MANUAL PRIOR TO
INSTALLING OR USING THIS PRODUCT. This manual
includes information on all four versions of the continuous ultrasonic level transmitter from Flowline; model LU20-50_1 and
LU20-50_1-IS. Please refer to the part number located on the sensor label to verify the exact model which you have purchased.
User’s Responsibility for Safety:
Flowline manufactures a wide range of liquid level sensors and
technologies. While each of these technologies are designed to
operate in a wide variety of applications, it is the user’s responsibility to select a technology that is appropriate for the application,
install it properly, perform tests of the installed system, and maintain all components. The failure to do so could result in property
damage or serious injury.
Proper Installation and Handling:
Because this is an electrically operated device, only properlytrained staff should install and/or repair this product. Use a proper
sealant with all installations. Note: Always install the 2” Viton gasket with the LU20-5061 and the LU20-5061-IS. The G threaded
version of the Echotouch will not seal unless the gasket is installed
properly. Never overtighten the transmitter within the fitting.
Always check for leaks prior to system start-up.
Wiring and Electrical:
A supply voltage of 12-36 VDC is used to power the LU20-50_1
transmitter and a supply voltage of 12-32 VDC is used to power the
LU20-50_1-IS. The sensor systems should never exceed a maximum of 36 VDC for the LU20-50_1 and 32 VDC for the LU2050_1-IS. Electrical wiring of the sensor should be performed in
accordance with all applicable national, state, and local codes.
Temperature and Pressure:
The LU20 is designed for use in application temperatures from -40
°C (-40 °F) to 60 °C (140 °F), and for use at pressures up to 30 psi
@ 25 °C, derated @ 1.667 psi per °C above 25 °C.
Material Compatibility:
The continuous ultrasonic level transmitter, LU20, is made of two
materials. The enclosure is of Polypropylene (PP) and the transducer is made of Polyvinylidene Fluoride (PVDF). Make sure that
the model which you have selected is chemically compatible with
the application liquids. While the transmitter housing is liquidresistant when installed properly, it is not designed to be immersed.
It should be mounted in such a way that it does not normally come
into contact with fluid.
Flammable, Explosive and Hazardous Applications:
Only the LU20-50_1-IS is rated for use in hazardous locations.
Refer to the Certificate of Compliance for all applicable intrinsically safe ratings and entity parameters for the LU20-50_1-IS.
Refer to the National Electric Code (NEC) for all applicable installation requirements in hazardous locations. DO NOT USE THE
LU20-50_1 GENERAL PURPOSE TRANSMITTER IN HAZARDOUS LOCATIONS.
Make a Fail-Safe System:
Design a fail-safe system that accommodates the possibility of
transmitter or power failure. In critical applications, Flowline recommends the use of redundant backup systems and alarms in addition to the primary system.
EC4: The 4 mA setting for the
LU20. The EC4 is the distance from
the bottom of the LU20 to the 4 mA
set point. This setting is measured in
either inches or centimeters on the
display. The EC4 setting is typically
greater that the EC20 setting.
EC20: The 20 mA setting for the
LU20. The EC20 is the distance
from the bottom of the LU20 to the
20 mA set point. This setting is measured in either inches or centimeters
on the display. The EC20 setting is
typically greater that the EC4 setting.
SAF1/SAF2/SAF3: Fail-Safe setting for the LU20. Use the SAF_
settings to determine a fail-safe mode for the current signal. When
[SAF1] is set, the current will increase to 22 mAif the signal becomes
LOST. When [SAF2] is set, the current will decrease to 4 mA if the
signal becomes LOST. When [SAF3] is set, the current will remain
constant if the signal becomes LOST.
FAST/SLOW:Setting for echo averaging on the LU20. [F AST] is the
typical setting for the LU20 to operate. [SLOW] is designed to help
dampen out effects caused by severe turbulence. In the [FAST] mode,
the LU20 will average 2 signal responses per second and update every
second. In the [SLOW] mode, the LU20 will average signal returns
over the preceding 10 seconds. When used with [SAF 1/2/3], the time
for the current to default is 30 seconds for [FAST] mode and 2.5 minutes for [SLOW] mode.
ALIN: Indicates that the unit is in the Alignment mode. Display will
show the return signal strength in dB’s. Used as an indicator for
mechanical alignment of the LU20 and/or signal attenuation. Typical
readings range between 2 and 60 dB’s. For optimum alignment, first
energize the unit and receive a valid return signal. Then select the
ALIN mode and adjust the LU20 until the display is maximized.
ON/OFF: Actual setting for ALIN mode. The ALIN mode must be
turned [OFF] when alignment is completed. This mode will not automatically default back to [LEVL].
MAXR: Used as an indication for [MAXR] or
maximum range. The MAXR sets the maximum tank height and will filter out all returns
greater than this value.
(value): Actual MAXR setting.
The maximum distance is 216.0
inches.
MINR: Used as an indication for
[MINR] or the minimum range.
The MINR value is the deadband
closest to the transducer face where
no signal will be generated. The
MINR sets the minimum distance
between the liquid and the transducer.
(value): Actual MINR setting. The minimum distance is 6.0 inches.
EC20
EC4
20 mA
4 mA
MINR
MAXR
Step Four Step Five
PROGRAMMING WIRING
EC4:
1. Hold [MENU] key until EC4 appears in display.
2. Release [MENU] key and wait until a value appears. This value is
the current measured level value.
3. If this is acceptable, press [SET] to lock the value as the new EC4
set point. If not, press either the [
s] or [t] keys once and the old
setting for the EC4 will appear.
4. From here, use the [s] or [t] keys to raise or lower the value to
the desired value.
5. Press the [SET] key to enter this value as the new EC4 set point.
EC20:
1. Hold [MENU] key until EC20 appears in display.
2. Release [MENU] key and wait until a value appears. This value is
the current measured level value.
3. If this is acceptable, press [SET] to lock the value as the new EC20
set point. If not, press either the [s] or [t] keys once and the old
setting for the EC4 will appear.
4. From here, use the [s] or [t] keys to raise or lower the value to
the desired value.
5. Press the [SET] key to enter this value as the new EC20 set point.
SAF1/SAF2/SAF3:
1. Hold [MENU] key until SAF1, SAF2 or SAF3 appears in the dis-
play.
2. Release [MENU] key and hold [SET] key to toggle between SAF1,
SAF2 and SAF3.
3. When desired setting is reached, release [SET] key. The last dis-
played setting will be locked into memory. To change, start again
at step 1.
FAST/SLOW:
1. Hold [MENU] key until FAST or SLOW appears in the display.
2. Release [MENU] key and hold [SET] key to toggle between FAST
and SLOW.
3. When desired setting is reached, release [SET] key. The last dis-
played setting will be locked into memory. To change, start again
at step 1.
ALIN:
1. Hold [MENU] key until ALIN appears in the display.
2. Continue to hold [MENU] key until OFF appears in the display.
3. Release [MENU] key and hold [SET] key to toggle from OFF to
ON.
4. Release [SET] key. The LU20 is now in ALIN mode.
5. To exit ALIN mode, repeat steps 1-4 changing from ON to OFF.
MAXR:
1. Hold [MENU] key until MAXR appears in the display.
2. Continue to hold [MENU] key until a value appears in the display.
This value is the current MAXR setting.
3. If this is acceptable, press [SET] to lock the value as the MAXR
setting. If not, use the [s] or [t] keys to raise or lower the value
to the desired setting.
4. Press the [SET] key to enter this value as the new MAXR setting.
MINR:
1. Hold [MENU] key until MINR appears in the display.
2. Continue to hold [MENU] key until a value appears in the display.
This value is the current MINR setting.
3. If this is acceptable, press [SET] to lock the value as the MINR set-
ting. If not, use the [s] or [t] keys to raise or lower the value to
the desired value.
4. Press the [SET] key to enter this value as the new MINR setting.
The LU20-50_1 requires 12-36 VDC power with at least 25 mA supply in order to operate.
1.Wiring to a Flowline Continuous Controller (Model LC52):
2.Wiring to a Two-Wire Loop Indicator (Model LU20-50_1):
3.Wiring to a PLC (LU20-50_1):
MENU
SET
Echotouch
TM
Ultrasonic Level
Transmitter
(+)
(-)
LATCH
ON OFF
PWR
RELAY 1
INVERT
DELAY
RELAY 2
INVERT
DELAY
4 20 OP
EASY CAL
UP DOWN SET
INPUT
0% 100%
OFF SET
SPAN
RLY1
RLY2A
RLY2B
+
-
DC Power
Supply
18-36 VDC
MENU
SET
Echotouch
TM
Ultrasonic Level
Transmitter
(+)
(-)
-
+
+
-
DC Power
Supply
18-36 VDC
Typical PLC
6
5
4
3
2
1
0
A
250Ω
MENU
SET
Echotouch
TM
Ultrasonic Level
Transmitter
(+)
(-)
Step Six Step Seven
INSTALLATION INSTALLATION
Minimum Range (MINR) Setting
If installing the LU20 in a flange or any
device which recesses the bottom of the
transmitter, use the MINR setting. The
minimum value for the MINR setting is
the distance from the bottom of the transmitter to the end of the flange. Never set
MINR to less than 6.0 inches.
Mounting the LU20 is critical to the successful operation of the transmitter. Avoid the following parameters:
Maximum Application Range
The maximum range of LU20 is 18 feet at 110 dB. Under less than
ideal conditions, a number of factors can reduce the overall quality of
signal return and shorten the accurate range of the transmitter. To
determine the maximum application range of the product, follow the
signal return formula against the echo attenuation graph below.
Echo Attenuation Graph
TYPICAL CURVE
10 dB ABSORPTION
20 dB ABSORPTION
ALIGN READING (dB)
10
20
30
40
50
40 80 120 160 200 240
00
DISTANCE FROM FACE OF TRANSDUCER (inches)
4
1
3
2
1: Distance from transducer = 40"
2: Highest possible ALIN = 28dB
(under ideal conditions)
Adjust mechanical alignment of unit
to maximize displayed ALIN value
• PREDICT MAXIMUM RANGE
USING ALIGN VALUE
3: If the actual ALIN = 18dB at D = 40"
4: Maximum Range = 138"
EXAMPLE:
• OPTIMIZE ALIGNMENT
MINR
VACUUM
Avoid
Interference
from side of
tank
Do not install
LU20 at
an angle
Avoid Inter-
ference from
obstructions
in tank
LU20 will not
operate in
vacuum
The LU20-50_1-IS requires 12-32 VDC power with at least 25 mA
supply in order to operate. The follow provides an overview of wiring
the LU20-50_1-IS to various devices. Please note that a barrier must
be installed between the Echotouch and the device and the barrier
must be located within the nonhazardous location.
1. Hazardous System Diagram
2.Wiring to a Flowline Continuous Controller
3.Wiring to a Two-Wire Loop Indicator
4.Wiring to a PLC
NON-HAZARDOUS
LOCATION
Model LU20
Ultrasonic
Level
Transmitter
Vmax = 32.0 V
Imax = 130 mA
Ci ≈ 0 µF
Li ≈ 0 µH
Any Approved
I.S. Barrier
Vdc ≤ 32.0 V
Isc ≤ 130 mA
Ca ≥ 0 µF
La ≥ 0 µH
HAZARDOUS
LOCATION
+
-
+
-
See LC52 manual for
jumper settings
LATCH
ON OFF
PWR
RELAY 1
INVERT
DELAY
RELAY 2
INVERT
DELAY
4 20 OP
EASY CAL
UP DOWN SET
INPUT
0% 100%
OFF SET
SPAN
RLY1
RLY2A
RLY2B
NON-HAZARDOUS LOCATION
Control drawing for the LU20-5001-IS ultrasonic level transmitter
approved under the entity concept as an I.S. apparatus
Control Drawing: LU20CD
Rev. 7-24-97
Model LU20
Ultrasonic
Level Transmitter
Vmax = 32.0 V
Imax = 130 mA
Ci ≈ 0 µF
Li ≈ 0 µH
Any Approved
I.S. Barrier
Vdc ≤ 32.0 V
Isc ≤ 130 mA
Ca ≥ 0 µF
La ≥ 0 µH
Supply
HAZARDOUS LOCATION
Class I, Div I, Groups A, B, C & D
+
-
NON-HAZARDOUS
LOCATION
Model LU20
Ultrasonic
Level
Transmitter
Vmax = 32.0 V
Imax = 130 mA
Ci ≈ 0 µF
Li ≈ 0 µH
Any Approved
I.S. Barrier
Vdc ≤ 32.0 V
Isc ≤ 130 mA
Ca ≥ 0 µF
La ≥ 0 µH
HAZARDOUS
LOCATION
+
-
+
-
-
+
DC Power
Supply
14-32 VDC
Typical PLC
6
5
4
3
2
1
0
A
250Ω
NON-HAZARDOUS
LOCATION
Model LU20
Ultrasonic
Level
Transmitter
Vmax = 32.0 V
Imax = 130 mA
Ci ≈ 0 µF
Li ≈ 0 µH
Any Approved
I.S. Barrier
Vdc ≤ 32.0 V
Isc ≤ 130 mA
Ca ≥ 0 µF
La ≥ 0 µH
HAZARDOUS
LOCATION
+
-
+
-
-
+
DC Power
Supply
14-32 VDC
Step Eight Step Nine
INSTALLATION TROUBLESHOOTING
LOST Signal:
A reading of LOST in the display of the LU20 indicates the transmitter is not receiving a valid return signal. If LOST appears, please
check the following troubleshooting items:
1. Beam cone interference such as the side wall, ladders, seams,
rungs or pipes within the LU20’s beam cone.
2. Proper installation such that the LU20 is installed level and free
from interference from the installation fitting or flange.
3. Sufficient power being supplied to the LU20. The LU20-50_1
requires 12-36 VDC power with a minimum supply of 25 mA.
The LU20-50_1-IS requires 12-32 VDC power with a minimum
supply of 25 mA.
4. Proper programming of the MAXR or MINR function. For best
results, set the MAXR function as the distance from the bottom of
the tank to the bottom of the transmitter. Also set the MINR distance above the highest level in the tank. Do not set the MINR to
less than 6 inches.
5. Make sure that the transmitter is not installed at an angle. Even a
5 degree offset can reduce the signal return strength greatly.
Other Hints:
Current must change with changes in level. Example: For the illustration below, as level increases, the current output will increase and as
the level decreases, the current output will decrease. If the output of
the LU20 is always reading 4 mA or 20 mA, check the input values
for the LU20.
Factory Settings:
The LU20 is preset at the factory. When powering up the transmitter
the first time, the factory settings will be active. If at any time in you
need to return to these settings, remove power from the LU20 and
wait 10 seconds. Press the [Set] and [Menu] buttons simultaneously
while powering up the transmitter.
Changing Display Units:
The LU20 comes preset to measure in inches. To change the unit to
display centimeters, remove power to the LU20 and wait 10 seconds.
Press [s] and [Set] simultaneously while powering up the transmitter. The LU20 will now read in centimeters. To return to inches,
remove power and wait 10 seconds. Press [t] and [Set] simultaneously while powering up the transmitter.
EC 4
EC20
216" (548.4 cm)
8" (20.3 cm)
OFF
MAXR
value
OFF
N/A
216" (548.4 cm)
SAF1/2/3 SAF1
Fast/Slow FAST
ALIN N/A
MINR
value
N/A
6" (15.2 cm)
Depth
Radius
EC20
EC4
20 mA
4 mA
Depth Radius Radius
(Feet) (Inches) (cm)
1 1.2 3.1
2 2.1 5.2
3 2.9 7.3
4 3.7 9.5
5 4.6 11.6
6 5.4 13.7
7 6.2 15.9
8 7.1 18.0
9 7.9 20.1
10 8.8 22.3
11 9.6 24.4
12 10.4 26.5
13 11.3 28.7
14 12.1 30.8
15 13.0 32.9
16 13.8 35.1
17 14.6 37.2
18 15.5 39.3
Warning
Always install the 2” Viton gasket with the LU20-5061 and the
LU20-5061-IS. The G threaded version of the Echotouch will not
seal unless the gasket is installed properly.
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