Endress+Hauser Turbimax CUS51D User manual

Products Solutions Services
BA00461C/07/EN/15.13
71219749
Operating Instructions
Turbimax CUS51D
Sensor for turbidity and solids content

Endress+Hauser
About this document
Notes on safety icons
The structure, signal words and safety colors of the signs comply with the specifications of
ANSI Z535.6 ("Product safety information in product manuals, instructions and other
collateral materials").
Symbols
Safety message structure Meaning
DANGER
!
Cause (/consequences)
Consequences if safety
message is not heeded
‣Corrective action
This symbol alerts you to a dangerous situation.
Failure to avoid the situation will result in a fatal or serious
injury.
WARNING
!
Cause (/consequences)
Consequences if safety
message is not heeded
‣Corrective action
This symbol alerts you to a dangerous situation.
Failure to avoid the situation can result in a fatal or serious
injury.
CAUTION
!
Cause (/consequences)
Consequences if safety
message is not heeded
‣Corrective action
This symbol alerts you to a dangerous situation.
Failure to avoid this situation can result in minor or
medium injury.
NOTICE
Cause/situation
Consequences if safety
message is not heeded
‣Action/note
This symbol alerts you to situations that can result in
damage to property and equipment.
Additional information, tips
Permitted or recommended
Forbidden or not recommended

Turbimax CUS51D
Endress+Hauser 3
Table of contents
1 Safety instructions . . . . . . . . . . . . . . . . . . 4
1.1 Requirements for the personnel . . . . . . . . . . . . . . . 4
1.2 Designated use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.3 Workplace safety . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4 Operational safety . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.5 Product safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Incoming acceptance and product
identification . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Incoming acceptance . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Product identification . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Certificates and approvals . . . . . . . . . . . . . . . . . . . . 6
3 Installation . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1 Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2 Installation instructions . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Installation examples . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Post-installation check . . . . . . . . . . . . . . . . . . . . . 14
4 Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1 Connecting to the transmitter . . . . . . . . . . . . . . . 15
4.2 Post-connection check . . . . . . . . . . . . . . . . . . . . . 15
5 Device description . . . . . . . . . . . . . . . . .16
5.1 Sensor design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.2 Measuring principle . . . . . . . . . . . . . . . . . . . . . . . 16
5.3 Measuring methods . . . . . . . . . . . . . . . . . . . . . . . 19
5.4 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.5 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.6 Stability criterion . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.7 Cyclic cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6 Diagnostics and troubleshooting. . . . . 30
7 Maintenance. . . . . . . . . . . . . . . . . . . . . . 31
7.1 Cleaning the sensor . . . . . . . . . . . . . . . . . . . . . . . 31
8 Repair. . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
8.1 Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
8.2 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
9 Accessories . . . . . . . . . . . . . . . . . . . . . . . 33
9.1 Assemblies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.2 Holder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.3 Compressed air cleaning . . . . . . . . . . . . . . . . . . . 34
9.4 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
10 Technical Data . . . . . . . . . . . . . . . . . . . . 35
10.1 Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
10.2 Performance characteristics . . . . . . . . . . . . . . . . . 36
10.3 Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
10.4 Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
10.5 Mechanical construction . . . . . . . . . . . . . . . . . . . . 38
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Safety instructions Turbimax CUS51D
4Endress+Hauser
1 Safety instructions
1.1 Requirements for the personnel
‣Installation, commissioning, operation and maintenance of the measuring system must
only be carried out by trained technical personnel.
‣The technical personnel must be authorized by the plant operator to carry out the
specified activities.
‣The electrical connection may only be performed by an electrical technician.
‣The technical personnel must have read and understood these Operating Instructions
and must follow the instructions they contain.
‣Measuring point faults may only be rectified by authorized and specially trained
personnel.
Repairs not described in the enclosed Operating Instructions may only be carried out
directly at the manufacturer's or by the service organization.
1.2 Designated use
CUS51D is a sensor designed to measure the turbidity and solids content of water and
wastewater.
The sensor is particularly suited for use in the following applications:
• Turbidity measurement in the outlet
• Suspended solids in the activated sludge basin and in the recirculation
• Suspended solids in the sludge treatment
• Filterable solids in the outlet
Any other use than the one described here compromises the safety of persons and the entire
measuring system and is not permitted.
The manufacturer is not liable for damage caused by improper or non-designated use.
1.3 Workplace safety
As the user, you are responsible for complying with the following safety conditions:
• Regulations for explosion protection
• Installation instructions
• Local standards and regulations
Electromagnetic compatibility
With regard to electromagnetic compatibility, this device has been tested in accordance with
the applicable European standards for industrial applications.
The electromagnetic compatibility indicated only applies to a device that has been connected
in accordance with the instructions in these Operating Instructions.
1.4 Operational safety
‣Before commissioning the entire measuring point, make sure all the connections are
correct. Ensure that electrical cables and hose connections are not damaged.
‣Do not operate damaged products, and safeguard them to ensure that they are not
operated inadvertently. Mark the damaged product as defective.
‣If faults cannot be rectified, the products must be taken out of service and secured against
unintentional commissioning.

Turbimax CUS51D Safety instructions
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1.5 Product safety
The product is designed to meet state-of-the-art safety requirements, has been tested and
left the factory in a condition in which it is safe to operate. Relevant regulations and
European standards have been observed.

Incoming acceptance and product identification Turbimax CUS51D
6Endress+Hauser
2 Incoming acceptance and product
identification
2.1 Incoming acceptance
‣Make sure the packaging is undamaged!
‣Inform the supplier about any damage to the packaging.
Keep the damaged packaging until the matter has been settled.
‣Make sure the contents are undamaged!
‣Inform the supplier about damage to the contents. Keep the damaged products until the
matter has been settled.
‣Check that the order is complete and agrees with your shipping documents.
‣The packaging material used to store or to transport the product must provide shock
protection and humidity protection. The original packaging offers the best protection.
Also, keep to the approved ambient conditions (see "Technical data").
‣If you have any questions, please contact your supplier or your local sales center.
2.2 Product identification
2.2.1 Nameplate
The nameplate contains the following information:
• Manufacturer data
•Ordercode
• Extended order code
• Serial number
• Operating conditions
•Safetyicons
Compare the order code on the nameplate with your order.
2.2.2 Identifying the product
The order code and serial number of your device can be found in the following locations:
• On the nameplate
• On the front page of these Operating Instructions
• In the delivery papers
To find out the version of your device, enter the order code indicated on the nameplate
in the search screen at the following address:
www.products.endress.com/order-ident
2.3 Scope of delivery
The scope of delivery comprises:
• 1 sensor Turbimax CUS51D in the ordered version
• 1 Operating Instructions BA00461C/07/EN
If you have any questions, please contact your supplier or your local sales center.
2.4 Certificates and approvals
Declaration of conformity
The product meets the requirements of the harmonized European standards. It thus
complies with the legal requirements of the EC directives.
The manufacturer confirms successful testing of the product by affixing the 4symbol.

Turbimax CUS51D Installation
Endress+Hauser 7
3Installation
3.1 Dimensions
a0013179
Fig. 1: Dimensions
See the "Accessories" section for the dimensions of the cleaning unit

Installation Turbimax CUS51D
8Endress+Hauser
3.2 Installation instructions
3.2.1 Measuring system
A complete measuring system comprises:
• Turbidity sensor Turbimax CUS51D
• Transmitter Liquiline
• Assembly:
– Assembly Flexdip CYA112 and holder system Flexdip CYH112 or
– Retractable assembly , e.g. Cleanfit CUA451
a0012965
Fig. 2: Measuring system with immersion assembly (example)
1
2
3
1
4
5
1 Holder system Flexdip CYH112 4 Assembly Flexdip CYA112
2 Transmitter Liquiline 5 Turbidity sensor Turbimax CUS51D
3 Weather protection roof

Turbimax CUS51D Installation
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a0013334
Fig. 3: Measuring system with immersion assembly (example)
2
3
5
4
1
1 Transmitter Liquiline 4 Assembly Flexdip CYA112
2 Weather protection roof 5 Turbidity sensor Turbimax CUS51D
3 Holder system Flexdip CYH112
a0012964
Fig. 4: Measuring system with retractable assembly
(example)
1 Turbidity sensor Turbimax CUS51D
2 Transmitter Liquiline
3 Retractable assembly Cleanfit CUA451
4 Flow direction
1
3
4
2

Installation Turbimax CUS51D
10 Endress+Hauser
3.3 Installation examples
3.3.1 Immersion operation
Fixed installation with wastewater assembly
This type of installation is particularly suitable for strong or turbulent flow
(>0.5 m/s (1.6 ft/ s)) in the basin or channels.
a0013383
Fig. 5: Installation secured on railing
1 Turbidity sensor Turbimax CUS51D
2 Flexdip CYA112 wastewater assembly
3 Flexdip CYH112 holder
4 Railing
a0012965
Fig. 6: Installation with upright post
1 Flexdip CYH112 holder
2 Multichannel transmitter Liquiline CM44x
3 Weather protection cover
4 Flexdip CYA112 wastewater assembly
5 Turbidity sensor Turbimax CUS51D
1
2
3
4
1
2
3
1
4
5

Turbimax CUS51D Installation
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Installation with chain retainer
The chain retainer is particularly suitable for applications that require a sufficient distance
between the mounting location and the edge of the aeration basin. As the assembly is freely
suspended, any vibration of the upright post is practically ruled out.
The swinging movement of the chain retainer enhances the self-cleaning effect of the
optical window.
a0013384
Fig. 7: Chain retainer on railing
1 Flexdip CYA112 wastewater assembly with Turbimax
CUS51D turbidity sensor
2 Chain
3 Flexdip CYH112 holder
4 Railing
a0013386
Fig. 8: Chain retainer on upright post
1 Flexdip CYH112 holder
2 Multichannel transmitter Liquiline CM44x
3 Weather protection cover
4 Flexdip CYA112 wastewater assembly
5 Turbidity sensor Turbimax CUS51D
1
2
3
4
1
2
3
1
4
5
4

Installation Turbimax CUS51D
12 Endress+Hauser
Cleaning unit
a0013259
Fig. 9: Turbimax CUS51D sensor with cleaning unit
The cleaning unit is particularly suitable for clear water and media containing fats/oils that
tend to cause heavy buildup.
Mount the cleaning unit as follows:
1. Fit the cleaning unit onto the sensor as far as it will go.
2. Locate the two LEDs (they are installed at an angle and have a bright enclosure).
3. Position the cleaning unit in such a way that the nozzle is located at the side of the two
LEDs (see å10).
4. Fix the cleaning unit in place with the securing screw (max. torque: 0.5 Nm
(0.37 lbf ft)).
5. Insert the compressed air hose of the compressor into the hose connection.
a0013410
Fig. 10: Aligning the cleaning unit
1LEDs
2Nozzle
a0013411
Fig. 11: Fixing the cleaning unit
1 Hose connection
2Securingscrew
1
2
1
1
2

Turbimax CUS51D Installation
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3.3.2 Pipe installation
a0013009
Fig. 12: Installation with retractable assembly
Arrow 1 shows the flow direction.
The installation angle must not exceed 90°.
The recommended installation angle is 75°.
The optical windows of the sensor have to be aligned
parallel to the flow direction (= 90°) or face the
flow direction (< 90°).
For manual insertion/retraction of the assembly the
medium pressure may not exceed 2 bar (29 psi).
a0015169
Fig. 13: Installation with flow assembly CYA251
The installation angle is 90°.
Turbidity measurement < 200 FNU will result in
erroneous measuring results due to backscattering of
pipe wall.

Installation Turbimax CUS51D
14 Endress+Hauser
The following figure illustrates various installation positions in pipes and indicates whether
they are permitted or not.
a0013011
Fig. 14: Orientation and installation positions (with retractable assembly CUA451)
• The pipeline diameter must be at least 100 mm (4") if reflective materials (e.g. stainless
steel) are used. An on-site calibration is recommended.
• Install the sensor in places with uniform flow conditions.
• The best installation location is in the ascending pipe (it. 1). Installation is also possible in
the horizontal pipe (it. 5).
• Do not install the sensor in places where air may collect or foam bubbles form (it. 3) or
where suspended particles may settle (it. 2).
• Avoid installation in the down pipe (it. 4).
• Turbidity measurement < 200 FNU will result in erroneous measuring results due to
backscattering of pipe wall. Therefore a multipoint calibration is recommended.
• Avoid installations behind pressure reduction steps which can outgas.
3.4 Post-installation check
‣Sensor and cable undamaged?
‣Cap undamaged?
‣Compliance with permissible sensor installation position?
‣Is the sensor installed in an assembly and is not suspended from the cable?
‣Avoid moisture by rain by putting the protective cap on the assembly?
4
5
2
2
1
3
3

Turbimax CUS51D Wiring
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4 Wiring
WARNING
!
Device is energized
Improper connection can cause injury or death.
‣The electrical connection must only be carried out by a certified electrician.
‣Technical personnel must have read and understood the instructions in this manual and
must adhere to them.
‣Prior to beginning any wiring work, make sure voltage is not applied to any of the cables.
4.1 Connecting to the transmitter
The sensor will be connected to the transmitter as follows:
• With the M12 plug (version: fixed cable, M12 plug) or
• With the fixed cable connected to the terminal strips (version: fixed cable, end sleeves):
a0012460
Fig. 15: Sensor connection
The maximum cable length is 100 m (328 ft).
4.2 Post-connection check
Instrument status and specifications Remarks
Are the sensor, assembly, junction box or cable damaged? Visual inspection
Electrical connection Remarks
Does the supply voltage of the transmitter match the specifications on
the nameplate?
Are the installed cables strain-relieved and not twisted ?
Is the cable type route completely isolated ? Power cable/weak current cable
Are the power supply and signal cable correctly connected to the
transmitter ?
Use the connection diagram of the
transmitter.
Long enough length of cable core stripped and correct in terminal? Check seating (pull slightly)
Are all the screws terminals properly tightened ? Tighten
Are all the cable entries installed, tightened and sealed ? For cable entries lateral: cable loops
downwards for water to be able to drip
off.
Are all the cable entries installed downwards or lateral ?

Device description Turbimax CUS51D
16 Endress+Hauser
5Devicedescription
5.1 Sensor design
The sensor is designed for the continuous in-situ measurement of turbidity and solids
content.
The sensor is designed as a 40 mm sensor that can be operated directly and completely in
the process without the need for further sampling (in situ).
All the necessary modules are contained in the sensor:
• Power supply
• Light sources
• Detectors detect the measuring signals, digitize them and process them to form a
measured value.
• The sensor microcontroller is responsible for controlling the internal processes and
transmitting the data.
All the data - including the calibration data - are stored in the sensor. The sensor can thus
be precalibrated and used at a measuring point, calibrated externally, or used for several
measuring points with different calibrations.
5.2 Measuring principle
For turbidity measurement a light beam is sent through the medium and is diverted from its
original direction by optically denser particles, e.g. solid matter particles. This process is also
called scattering.
The impinging light will be scattered in different angles. Two angles are of interest in this
matter:
• The scattered light in the 90° direction is less influenced by the size of the particles.
• The scattered light in the 135° direction gives enough information also at a high number
of particles.
a0013159
Fig. 16: Deflection of the light
1
2
3
4
Light source
Light beam
particle
Scattered light
1
2
3
4
4
4

Turbimax CUS51D Device description
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a0012986
Fig. 17: Principle operating mode of the turbidity sensor
1Lightsource
2 135° light receiver
3 90° light receiver
If only a small number of particles is in the medium, most of the light will be scattered to the
90° channel and less light will be scattered to the 135° channel. When the number of
particles increases the relationship will change (more light scattered to the 135° channel,
less light scattered to the 90°channel).
a0013158
Fig. 18: Signal distribution depending on the number of particles
Ir Relative intensity
90°
135°
123
1
Ir
FNU
90°
135°

Device description Turbimax CUS51D
18 Endress+Hauser
The turbidity sensor CUS51D is equipped with two independent sensor units that are
arranged in parallel. The application-specific analysis of both signals results in stable
measured values.
a0012966
Fig. 19: Arrangement of the light souces and the light receivers
1,2 Light sources 1 and 2
3,5 135° light receivers
4,6 90° light receivers
This allows the optimal turbidity and suspended solids measurement:
• For low turbidity values preferably the 90° channel is used.
• For average and high turbidity values and for suspended solids measurement the 135°
channel is used.
• The dual sensor technology allows operation with a large range of soiling compensation,
e.g. suspended solids measurement in the activated sludge basin (basis: four-beam pulsed
light).
Based on the chosen application the appropriate model is used automatically inside the
sensor.
The available sensor types differ in their measuring ranges and therefore in the
selection of the available applications.
12
3
4
5
6

Turbimax CUS51D Device description
Endress+Hauser 19
5.3 Measuring methods
Four-beam pulsed light method
The method is based on two light sources and four light receivers. Long-life LEDs are used
as monochromatic light sources. To eliminate interference from extraneous light sources,
these LEDs are pulsed.
Two measuring signals are detected at the four light receivers. The eight measuring signals
are processed in the sensor and are converted into turbidity units and solids concentrations.
The four-beam pulsed light method compensates the sensor soiling as well as the wearing
of the optical components.
The number of the used signals depends on the application.
a0012987
Fig. 20: Four-beam pulsed light method
S1S2Light sources
E9090° channel light-receiver
E135135° channel light-receiver
90° scattered light method
The measurement uses a wavelength of 860 nm like described in ISO 7027 / EN 27027.
The transmitted light beam is scattered by the solid matter particles in the medium. The
scattered beams are detected by scattered light receivers which are arranged at an angle of
90 ° to the light sources. The turbidity of the medium is determined by the amount of the
scattered light.
S1E1-135
E2-135
S2
E1-90
E2-90
a0013168
Fig. 21: Principle of the 90° scattered light method
S = Light source
E = Light receiver
P = Particle
S
E
a
P

Device description Turbimax CUS51D
20 Endress+Hauser
135° backscattered light method
The transmitted light beam is scattered by the solid matter particles in the medium. The
backscattered beams are detected by scattered light receivers, which are arranged next to
the light sources. The turbidity of the medium is determined by the amount of backscattered
light.
This method is used to measure high turbidity values.
a0013304
Fig. 22: Principle of backscattered light method
I0= Intensity of transmitted light
IS= Intensity of backscattered light
A = Geometric factor
C = Concentration
P = Particle
f(
 ) = Angle dependence
S1
E1P
I0
IS
a
I =I ·C·A·f( )
s0 a