Endress+Hauser CYA251 User manual

BA00495C/07/EN/02.12
71189534
Operating Instructions
Flowfit CYA251
Flow assembly for nitrate/SAC, turbidity and oxygen sensors

Flowfit CYA251
Endress+Hauser 3
Table of contents
1 Safety instructions . . . . . . . . . . . . . . . . 4
1.1 Designated use . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Installation, commissioning and operation . . . . . . . . 4
1.3 Operational safety . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4 Notes on safety icons and symbols . . . . . . . . . . . . . . 5
2 Identification . . . . . . . . . . . . . . . . . . . . 6
2.1 Nameplate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Order code and device version . . . . . . . . . . . . . . . . . 6
2.3 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Installation . . . . . . . . . . . . . . . . . . . . . . 7
3.1 Incoming acceptance, transport, storage . . . . . . . . . . 7
3.2 Installation conditions . . . . . . . . . . . . . . . . . . . . . . . 7
3.3 Installation instructions . . . . . . . . . . . . . . . . . . . . . 10
3.4 Installation with wall holder unit . . . . . . . . . . . . . . 11
3.5 Sensor installation . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.6 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.7 Post-installation check . . . . . . . . . . . . . . . . . . . . . . 14
4 Commissioning. . . . . . . . . . . . . . . . . . 15
5 Maintenance. . . . . . . . . . . . . . . . . . . . 16
5.1 Cleaning the assembly . . . . . . . . . . . . . . . . . . . . . . 16
5.2 Cleaning the sensor . . . . . . . . . . . . . . . . . . . . . . . . 16
5.3 Cleaning agents . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.4 Replacing the seals . . . . . . . . . . . . . . . . . . . . . . . . 17
6 Accessories. . . . . . . . . . . . . . . . . . . . . 18
6.1 Cleaning nozzle . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.2 Sensor adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.3 Wall holder unit . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7 Troubleshooting . . . . . . . . . . . . . . . . . 20
7.1 Replacing damaged parts . . . . . . . . . . . . . . . . . . . . 20
7.2 Spare parts kits . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.3 Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.4 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
8 Technical Data . . . . . . . . . . . . . . . . . . 21
8.1 Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
8.2 Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
8.3 Mechanical construction . . . . . . . . . . . . . . . . . . . . 21
Index . . . . . . . . . . . . . . . . . . . . . . . . . 23

Safety instructions Flowfit CYA251
4Endress+Hauser
1 Safety instructions
1.1 Designated use
The CYA251 flow assembly is designed for the installation of nitrate/SAC, turbidity and oxygen
sensors, each with a diameter of 40 mm. The assembly is used in pipes and hoses.
Thanks to its special design, it is possible to operate the flow assembly in pressurized systems (see
"Technical data").
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.
1.2 Installation, commissioning and operation
Please note the following items:
• Switch off the cleaning unit before removing the sensor from the medium.
• Installation, commissioning, operation and maintenance of the measuring system must only be
carried out by trained technical personnel.
Trained personnel must be authorized for the specified activities by the system operator.
• Electrical connection must only be carried out by a certified electrician.
• Technical personnel must have read and understood these Operating Instructions and must
adhere to them.
• Before commissioning the entire measuring point, check all the connections. Ensure that
electrical cables and hose connections are not damaged.
• Do not operate damaged products and secure them against unintentional commissioning.
Mark the damaged product as being defective.
• Measuring point faults may only be rectified by authorized and specially trained personnel.
• If faults can not be rectified, the products must be taken out of service and secured against
unintentional commissioning.
• Repairs not described in these Operating Instructions may only be carried out at the
manufacturer’s or by the service organization.
1.3 Operational safety
The sensor has been designed and tested according to the state of the art and left the factory in
perfect functioning order.
Relevant regulations and European standards have been met.
As the user, you are responsible for complying with the following safety conditions:
• Installation instructions
• Local prevailing standards and regulations.

Flowfit CYA251 Safety instructions
Endress+Hauser 5
1.4 Notes on safety icons and symbols
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").
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.
È ä 1 This symbol indicates a cross reference to a defined page (e.g. p. 1).
È å 2 This symbol indicates a cross reference to a defined figure (e.g. fig. 2).

Identification Flowfit CYA251
6Endress+Hauser
2 Identification
2.1 Nameplate
The nameplate contains the following information:
• Manufacturer data
•Ordercode
• Extended order code
• Serial number
• Operating conditions
• Safety icons
Compare the order code on the nameplate with your order.
2.2 Order code and device version
Enter the following address in your browser to access the product page:
www.products.endress.com/cya251
1. You can choose from the following options on the product page located on the right:
2. Click "Configure this product".
3. The configurator opens in a separate window. You can now configure your device and receive
the complete order code that applies for the device.
4. Afterwards, export the order code as a PDF or Excel file. To do so, click the appropriate button
at the top of the page.
2.3 Scope of delivery
The scope of delivery comprises:
• Flow assembly in the version ordered (contains the sensor adapter and process connection)
• Accessories ordered
• Adapter with check valve (for optional cleaning only, 6 mm connection for compressed air)
• 1 tube of lubricant (for O-rings)
• Operating Instructions, English
When the flow assembly is delivered, the cleaning port and cleaning connection are fitted with
dummy plugs.
If you have any questions, please contact your supplier or your local sales center.

Flowfit CYA251 Installation
Endress+Hauser 7
3 Installation
3.1 Incoming acceptance, transport, storage
• 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.
3.2 Installation conditions
3.2.1 Dimensions
a0016082
Fig. 1: Dimensions
Sensor CAS51D
2 mm
CAS51D
8 mm
CAS51D
40 mm
COS51D
COS41
COS61D
COS61
COS31
CUS31
CUS41
CUS51D
Zmm(inch) 468 (18.43) 471 (18.54) 477 (18.78) 284 (11.18) 326 (12.83) 325 (12.80) 332 (13.07)
Connections NPT ¾" Rp ¾ DN 25 ANSI 1" Hose D20 G1¼
Xmm(inch) 83 (3.27) 83 (3.27) 83 (3.27) 50 (1.97) 137 (5.39) 61 (2.40)
Ymm(inch) 50.5 (1.99) 50.5 (1.99) 50.5 (1.99) 115 (4.53) 50.5 (1.99) 44.5 (1.75)

Installation Flowfit CYA251
8Endress+Hauser
3.2.2 Notes on installation
To ensure that medium flows through the assembly in a bypass configuration, the pressure p1 must
be greater than the pressure p2. This is achieved by installing an orifice plate in the main pipe.
a0016023
Fig. 2: Connection example involving a bypass and an orifice plate in the main pipe
a0017221
Abb. 3: Connection example involving a bypass and an orifice plate in the main pipe (assembly rotated by 90 °, inlet
at bottom)
p1 p2 p1 > p2

Flowfit CYA251 Installation
Endress+Hauser 9
No measures to increase pressure are required for branch pipes that branch off from the main pipe.
a0016024
Fig. 4: Connection example involving an open outlet
The inlet and outlet connection of the flow assembly are always identical.
The inlet and outlet side are not specified by the flow assembly and can therefore be selected to suit
the particular application.
The flow assembly is designed to be connected to pipes and hoses. You require the following at the
mounting location to install the assembly:
Part name Where required ...
Two shutoff valves For the bypass solution
One shutoff valve For the solution with an open outlet
Orifice plate in the main pipe For the bypass solution
Dirt filter (500 μm or finer) If the medium contains coarse dirt particles
Pressure-reducing valve If the pressure of the medium is higher than the
permitted value (see "Technical data" section)
Wall holder unit (see "Accessories" section) to secure the
assembly
For hose connections
Pipe or hose connections to the assembly For all versions

Installation Flowfit CYA251
10 Endress+Hauser
3.3 Installation instructions
3.3.1 Measuring system
A complete measuring system comprises:
• Flowfit CYA251 flow assembly
• A 40 mm sensor, e.g. CAS51D
• Transmitter, e.g. Liquiline CM442
• Measuring cable
a0016022
Fig. 5: Measuring system (example)
1 Process pipe
2 Liquiline CM442 transmitter
3 Measuring cable
4 Return line with shutoff valve
5 CYA251 flow assembly with 40 mm sensor
6 Inlet with shutoff valve

Flowfit CYA251 Installation
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3.4 Installation with wall holder unit
a0016088
Fig. 6: Wall holder unit
1 Hanger bolt STST 10x60 (forms part of the delivery)
Please comply with the following instructions when installing the flow assembly:
• Mount the flow assembly either
– in a bypass
In the bypass pipe, install a shutoff valve upstream and downstream of the flow assembly. This
makes it possible to clean the sensor or perform other maintenance tasks without affecting the
process.
– or in a branch pipe with an open outlet
Install a shutoff valve upstream of the flow assembly.
• Mount the assembly in a vertical, upright position or rotated by 90 °. Make sure that the position
of the inlet guarantees automatic venting.
• Establish the medium connection using commercially available connection fittings.
• If the medium contains coarse dirt particles, install a filter upstream of the flow assembly.
NOTICE
Observe the maximum permissible medium pressure for the assembly and sensor.
• You must install a pressure-reducing valve upstream of the flowmeter if the pressure of the
medium is higher than the maximum value. The permissible medium pressure depends on the
temperature (see "Technical data").

Installation Flowfit CYA251
12 Endress+Hauser
3.5 Sensor installation
3.5.1 Preparatory steps
NOTICE
The inside of the flow assembly is not symmetrical.
• You can identify the difference from the outside as follows: the bottom inlet to the assembly is
sealed by a dummy cover when delivered.
a0016101
Fig. 7: Assembly body with bottom fixing ring and dummy cover
1 Inner O-ring "at top"
2 Inner O-ring "at bottom"
3Dummycover
4 Bottom fixing ring
Prepare to install the sensor as follows:
1. Lightly lubricate the O-ring on the sensor head.
2. Loosen the bottom fixing ring and remove the dummy cover.
3. Make sure that there is lubricant on the bottom O-ring inside the flow assembly.
4. Screw the dummy cover and the fixing ring back on.
5. Make sure that there is lubricant on the top O-ring inside the flow assembly.
6. Only for oxygen sensors: unscrew the basket protector from the sensor.
2
3
4
1

Flowfit CYA251 Installation
Endress+Hauser 13
3.5.2 Installing oxygen and turbidity sensors
Install the sensor as follows:
1. Guide the sensor into the sensor adapter (→å8).
2. Using the counter nut, secure the sensor in the sensor adapter.
3. Insert the sensor into the flow assembly.
4. For the CUS51D sensor:
Align the sensor as illustrated in →å9 as follows. Locate the two LEDs (they are installed
at an angle and have a bright enclosure). Align the sensor in such a way that the cleaning
connection is on the LED side (see arrow). The following step only applies if the cleaning
option has been ordered: plug the cleaning nozzle into the cleaning connection in such a way
that the nozzle opening is pointing upwards. Secure the position of the cleaning nozzle with
an open-ended wrench (AF 17 mm) and tighten the fixing ring on the cleaning connection.
For the CUS31 sensor:
Align the sensor as illustrated in →å10. The slanted side must point in the direction of the
cleaning connection. The following step only applies if the cleaning option has been ordered:
plug the cleaning nozzle into the cleaning connection and tighten the fixing ring on the
cleaning connection.
For the COS61 and COS51D sensors:
No special alignment applies for the COS61 and COS51D oxygen sensors. The following step
only applies if the cleaning option has been ordered: plug the cleaning nozzle into the cleaning
connection in such a way that the nozzle opening is pointing upwards. Secure the position of
the cleaning nozzle with an open-ended wrench (AF 17 mm) and tighten the fixing ring on
the cleaning connection.
5. Tighten the fixing ring (→å8) on the flow assembly.
a0016092
Fig. 8: Installation sleeve
1 Fixing ring
2 Counter nut
3 Sensor adapter
4Sensor
a0016095
Fig. 9: CUS51D
1 Receiver
2LED
a0016096
Fig. 10: CUS31
11
1
2
1
2

Installation Flowfit CYA251
14 Endress+Hauser
3.5.3 Installing the CAS51D sensor
Install the sensor as follows:
1. Guide the sensor into the sensor adapter (→å11).
2. Using the counter nut, secure the sensor in the sensor adapter.
3. Insert the sensor into the flow assembly.
4. For sensors with a 2 mm or 8 mm gap:
Align the sensor as illustrated in →å12. The threaded opening (at rear of gap) must be
located at the cleaning connection exactly. This ensures that the medium flows through the
measurement gap. The following step only applies if the cleaning option has been ordered:
screw the cleaning nozzle into the threaded opening of the sensor (finger-tight, max. 0.2 Nm
(0.15 lbf ft)). Tighten the fixing ring on the cleaning connection.
For sensors with a 40 mm gap:
Align the sensor as illustrated in →å13. The gap must be located at the cleaning connection
exactly. This ensures that the medium flows through the measurement gap. The following step
only applies if the cleaning option has been ordered: plug the cleaning nozzle into the cleaning
connection in such a way that the nozzle openings point upwards and downwards. Secure the
position of the cleaning nozzle with an open-ended wrench (AF 17 mm) and tighten the fixing
ring on the cleaning connection.
5. Tighten the fixing ring (→å11) on the flow assembly.
3.6 Cleaning
The flow assembly is optionally fitted with a cleaning nozzle.
Connect the compressed air hose to the attached cleaning nozzle via an additional adapter (G¼ to
6 mm) with a check valve.
3.7 Post-installation check
• After installation, check that all connections are firmly in position and leak-tight.
• Ensure that the hoses cannot be removed without force.
• Check all hoses for damage.
a0016092
Fig. 11: Installation sleeve
1 Fixing ring
2 Counter nut
3 Sensor adapter
4Sensor
a0016090
Fig. 12: CAS51D 2/8 mm
a0016091
Fig. 13: CAS51D 40 mm

Flowfit CYA251 Commissioning
Endress+Hauser 15
4 Commissioning
Prior to initial commissioning, make sure that:
• All the seals are seated correctly (on the assembly and the process connection)
• The sensor is correctly installed and connected
WARNING
!
Medium incorrectly connected to the assembly
Danger of medium leaking
• Before applying pressure to an assembly, make sure the medium is connected correctly.
Otherwise do not introduce the assembly into the process!

Maintenance Flowfit CYA251
16 Endress+Hauser
5 Maintenance
WARNING
!
Risk of injury if medium or cleaner escapes!
• Prior to performing any maintenance task, make sure that the process pipe is unpressurized,
empty and rinsed.
• Switch off the cleaning unit before removing the sensor from the medium.
5.1 Cleaning the assembly
All parts in contact with the medium, e.g. the sensor and the sensor holder, must be cleaned at
regular intervals. Remove the sensor1).
• Remove light dirt using suitable cleaning agents (see chapter "Cleaning agents").
• Remove severe fouling with a soft brush and a suitable cleaning agent.
• Remove persistant fouling by soaking in a liquid cleaner and if neccessary by cleaning with a soft
brush.
A typical cleaning interval for e.g. drinking water is at least half a year.
5.2 Cleaning the sensor
You must clean the sensor:
• Before every calibration
• At regular intervals during operation
• Before returning the sensor for repair
• In line with the operating conditions, but at least twice a year
If a cleaning nozzle (accessory) is installed, you can clean the sensor surfaces during operation. A
system pressure of 1 to 2 bar (15 to 29 psi) above the process pressure is recommended for the
cleaning nozzle.
If the assembly does not have a cleaning nozzle, you must remove the sensor and clean it manually.
In the case of oxygen and turbidity sensors, you can clean the sensor surfaces via the cleaning port.
NOTICE
Incorrect cleaning can damage the sensor or corrupt the measurement result.
• Only clean the outside of the sensor. Do not open the sensor!
• Do not use any abrasive cleaning agents as they can do irreparable damage to the sensor.
• After cleaning the sensor, rinse the assembly chamber thoroughly with water. Otherwise
cleaning agent residues can corrupt the measurement.
• If necessary, recalibrate the sensor after cleaning it.
1) in reverse sequence of operations to the installation procedure

Flowfit CYA251 Maintenance
Endress+Hauser 17
5.3 Cleaning agents
The choice of cleaning agent depends on the degree and type of fouling. The most common types
of dirt and fouling and the suitable cleaning agents are listed in the following table.
CAUTION
!
Solvents can cause a health hazard
• Never use acetone or any organic solvents containing halogens. Such solvents can damage
plastic parts of the sensor and some are suspected of causing cancer (e.g. chloroform).
5.4 Replacing the seals
You must interrupt the process and remove the assembly entirely to replace the seals in the
assembly.
WARNING
!
Medium can cause injury!
• When handling parts that are in contact with medium, take suitable precautions to protect
yourself from high temperatures and residual medium. Wear protective safety gloves and
goggles.
The seals are available as a spare parts kit (see the "Spare parts kits" section).
Clean the assembly before you replace the seals (see the "Cleaning the assembly" section).
Apply a thin layer of lubricant (e.g. Syntheso Glep1) to the new seals.
a0016107
Fig. 14: Position of the O-rings
Type of fouling Cleaning agent
Greases and oils Agents containing surfactants (alkaline agents) or water-soluble
organic solvents (halogen-free, e.g. ethanol)
Limescale deposits, metal hydroxide buildup,
lyophobic biological buildup
Approx. 3% hydrochloric acid
Sulfide deposits Mixture of 3% hydrochloric acid and thiocarbamide (usual
commercial)
Protein buildup Mixture of 3% hydrochloric acid and pepsin (usual commercial)
Fibers, suspended substances Pressurized water, possibly surface-active agent
Light biological buildup Pressurized water

Accessories Flowfit CYA251
18 Endress+Hauser
6Accessories
6.1 Cleaning nozzle
Cleaning nozzle for CYA251
• For automatic sensor cleaning.
• Order number: 71144328 (suitable for the CAS51D sensor (2 mm or 8 mm gap))
• Order number: 71144330 (suitable for the CAS51D sensor (40 mm gap))
• Order number: 71144331 (suitable for the CUS51D, COS51D, COS61D, COS61, COS31,
COS41 sensors)
• Order number: 71144332 (suitable for the CUS31, CUS41 sensors)
a0017219
Abb. 15: CYA251 with cleaning nozzle
1 Cleaning nozzle
6.2 Sensor adapter
Sensor adapter for CYA251
• Adapter for installing the following sensors:
• Order number: 71144333 (suitable for the COS61D, COS61, COS31 sensors)
• Order number: 71144334 (suitable for the COS41, COS51D sensors)
• Order number: 71144335 (suitable for the CUS51D sensor)
• Order number: 71144336 (suitable for the CUS31, CUS41 sensors)
• Order number: 71144337 (suitable for the CAS51D sensor (2 mm gap))
• Order number: 71144338 (suitable for the CAS51D sensor (8 mm gap))
• Order number: 71144339 (suitable for the CAS51D sensor (40 mm gap))
a0017220
Abb. 16: CYA251 with sensor adapter
1 Sensor adapter
1
1

Flowfit CYA251 Accessories
Endress+Hauser 19
6.3 Wall holder unit
Wall mounting kit for CYA251
• Order number: 71144369
a0016088
Fig. 17: Wall mounting kit
1 Hanger bolt STST 10x60 mm

Troubleshooting Flowfit CYA251
20 Endress+Hauser
7Troubleshooting
7.1 Replacing damaged parts
WARNING
!
Incorrectly repaired devices can cause hazard
• Assembly damage which affects the pressure safety may only be repaired by authorized
technical personnel.
• Following every repair and maintenance task, suitable measures must be taken to ensure that
the assembly is leak-tight. The assembly must again meet the technical data specifications when
it has been repaired.
Replace all other damaged parts immediately.
7.2 Spare parts kits
a0016112
Fig. 18: Spare parts
1 Fixing ring
2 O-ring kit
3 Fixing ring
Detailed information on the spare parts kits is available in the "Spare Part Finding Tool", which can
be accessed on the Web at:
www.products.endress.com/spareparts_consumables
7.3 Return
The device must be returned if repairs or a factory calibration are required, or if the wrong device
has been ordered or delivered. According to legal regulations, Endress+Hauser, as an ISO-certified
company, is required to follow certain procedures when handling returned products that are in
contact with medium.
To ensure swift, safe and professional device returns, please read the return procedures and
conditions on the internet site:
www.services.endress.com/return-material
7.4 Disposal
Please dispose of the device in accordance with the local regulations.
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2
2
2
2
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