Knick ARD75 User manual

Supplementary
Documentation
ARD75
Sensor adapter with lock-gate
function
www.knick.de
Read before installation.
Keep for future use.

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Supplemental Directives
READ AND SAVE THIS DOCUMENT FOR FUTURE REFERENCE. BEFORE ATTEMPTING TO ASSEMBLE, INSTALL,
OPERATE OR MAINTAIN THE PRODUCT, PLEASE ENSURE A COMPLETE UNDERSTANDING OF THE INSTRUC-
TIONS AND RISKS DESCRIBED HEREIN. ALWAYS OBSERVE ALL SAFETY INFORMATION. FAILURE TO COMPLY
WITH INSTRUCTIONS IN THIS DOCUMENT COULD RESULT IN SERIOUS INJURY AND/OR PROPERTY DAMAGE.
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE.
These supplemental directives explain how safety information is laid out in this document and what
content it covers.
Safety Chapter
This document's safety chapter is designed to give the reader a basic understanding of safety.
It illustrates general hazards and gives strategies on how to avoid them.
Warnings
This document uses the following warnings to indicate hazardous situations:
Symbol Category Meaning Remark
WARNING Designates a situation that can lead to death or serious
(irreversible) injury.
The warnings contain
information on how to
avoid the hazard.
CAUTION Designates a situation that can lead to slight or moderate
(reversible) injury.
None NOTICE Designates a situation that can lead to property or
environmental damage.
Symbols Used in this Document
Symbol Meaning
Reference to additional information
Interim or final result in instructions for action
Sequence of figures attached to an instruction for action
Item number in a figure
Item number in text

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Table of Contents
1 Safety............................................................................................................................................. 4
1.1 Intended Use.......................................................................................................................................................... 4
1.2 Residual Risks......................................................................................................................................................... 4
1.3 Hazardous Substances........................................................................................................................................ 5
2 Product.......................................................................................................................................... 6
2.1 Package Contents................................................................................................................................................. 6
2.2 Sensor Adapter Design and Function........................................................................................................... 6
2.3 Symbols and Markings ....................................................................................................................................... 7
2.4 Limit Positions ....................................................................................................................................................... 8
3 Installation.................................................................................................................................... 9
3.1 Inlet and Outlet Hose: Installation.................................................................................................................. 9
3.2 Drive Medium: Installation................................................................................................................................ 11
4 Commissioning............................................................................................................................. 13
5 Operation ...................................................................................................................................... 14
5.1 Moving into the Service and Process Position........................................................................................... 14
5.2 Installing and Removing the Sensor Adapter............................................................................................ 15
5.3 Installing and Removing Sensors ................................................................................................................... 17
5.4 Cleaning and Rinsing the Sensor.................................................................................................................... 19
6 Maintenance ................................................................................................................................. 20
6.1 Inspection and Maintenance ........................................................................................................................... 20
6.1.1 Inspection and Maintenance Intervals............................................................................................ 20
6.2 Corrective Maintenance..................................................................................................................................... 21
6.2.1 Corrective Maintenance Safety Instructions ................................................................................. 21
6.2.2 Removing and Installing the Rinsing Chamber ........................................................................... 21
6.2.3 Removing and Installing the Immersion Tube ............................................................................. 23
6.2.4 Replacing the O-Rings........................................................................................................................... 25
7 Troubleshooting ........................................................................................................................... 27
8 Removal from Operation ............................................................................................................. 28
8.1 Sensor Adapter: Removal .................................................................................................................................. 28
8.2 Returns ..................................................................................................................................................................... 28
8.3 Disposal.................................................................................................................................................................... 28
9 Accessories.................................................................................................................................... 29
9.1 Check Valve RV/01................................................................................................................................................ 29
9.2 Accessories.............................................................................................................................................................. 29
10 Dimension Drawings .................................................................................................................... 30
11 Specifications................................................................................................................................ 31
Appendices ................................................................................................................................... 32
Index.............................................................................................................................................. 34

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1 Safety
This document contains important instructions for the use of the product. Always follow all
instructions and operate the product with caution. If you have any questions, please contact Knick
Elektronische Messgeräte GmbH & Co. KG (sometimes hereafter referred to as "Knick") using the
information provided on the back page of this document.
Also follow the Safety Instructions provided in the User Manual for the ARD75 immersion fitting.
1.1 Intended Use
The sensor adapter with lock-gate function is intended for installation in the ARD75 immersion fitting.
The sensor is immersed in the process medium by the sensor adapter. The sensor adapter with lock-
gate function is powered pneumatically or water-hydraulically.
In the service position, the sensor can be rinsed or cleaned under process conditions.
If the product is used with any product or part not authorized by Knick, the operating company
assumes all risks and liabilities related thereto.
The sensor adapter with lock-gate function is suitable for use with the following sensor types:
Solid-electrolyte sensors Body diameter 12mm, body length120 mm, sensor head thread PG13.5
For further information, refer to the applicable documentation of the sensor manufacturer.
The defined operating conditions must be observed when using this product. ➜Specifications, p. 31
All designations such as “device” or “product” refer to the sensor adapter.
1.2 Residual Risks
The product has been developed and manufactured in accordance with generally accepted safety
rules and regulations, as well as an internal risk assessment. Despite the foregoing, the product may
among others bear the following risks:
Environmental Influences
The effects of chemicals and ambient temperature can negatively impact the safe operation of the
product. Observe the following instructions:
• Only operate the ARD75 in compliance with the stated operating conditions.
➜Specifications, p. 31
• If using aggressive chemical process media, adjust the inspection and maintenance intervals ac-
cordingly. ➜Inspection and Maintenance Intervals, p. 20
• Adhering and sticky process media can impact on the functionality of the product (e.g., by causing
components to stick together). Adjust the inspection and maintenance intervals accordingly.
➜Inspection and Maintenance Intervals, p. 20

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1.3 Hazardous Substances
In certain situations (e.g., sensor replacement or corrective maintenance), personnel may come into
contact with hazardous substances in the process medium.
• Process medium
• Rinsing or cleaning medium
The operating company is responsible for conducting a hazard assessment.
See the relevant manufacturers’ safety data sheets for hazard and safety instructions on handling
hazardous substances.
If the sensor adapter with lock-gate function is connected to the drinking water supply, impurities
caused by the rinse and process media is possible. Note the information in EN1717. Install a suitable
check valve at the water or rinse connection. ➜Accessories, p. 29

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2 Product
2.1 Package Contents
The package should contain:
• Sensor adapter with lock-gate function in the version ordered
• Supplementary Documentation
2.2 Sensor Adapter Design and Function
1
2
4
5
6
7
8
9
11
12
13
3
10
1Sensor 8Sensor adapter / cylinder drive
2Protection sleeve 9Piston rod with sensor holder
3Drive medium tubing holder 10 Piston with O-ring
4Drive medium connection process position 11 Immersion tube
5Drive medium connection service position 12 Rinsing chamber
6Inlet of rinse medium with check valve 13 Coupling nut
7Rinse medium outlet

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Sensor Adapter Function
The sensor adapter with lock-gate function contains a cylinder with a double-acting piston (piston rod
with sensor holder and immersion tube (9) and (11)). Depending on the pressurization (4) or (5), the
piston (10) is moved with the sensor (1) to the service or process position. ➜Limit Positions, p. 8
The piston rod with sensor holder (9) is connected to the immersion tube (11).
If the sensor is not present or present but improperly installed, the piston (10) does not move to the
process position due to guaranteed pressure equalization between the two sides of the piston (10).
➜Moving into the Service and Process Position, p. 14 This acts as protection from any unintended
movement to the process position.
The openings in the immersion tube (11) enable contact between the sensor tip and the process
medium when in the process position. In the service position, the immersion tube (11) moves through
the rinsing chamber (12). The sensor (1) can be rinsed or cleaned.
The layout of the openings in the immersion tube (11), in combination with the O-ring positions,
lock the outlet (7) of the rinsing chamber (12) while the sensor adapter (8) is moved to the process
position.
The inlet (6) of the rinsing chamber features a check valve for preventing any retroactive contamina-
tion of the pipe network.
2.3 Symbols and Markings
Special conditions and danger points! Observe the safety information and instructions on safe use of the
product as outlined in the product documentation.
P
Connection of the drive medium for moving to the process position.
Connection of the drive medium for moving to the service position.
Outlet for cleaning, rinse, or calibration media.
Inlet for cleaning, rinse, or calibration media.
Inlet check valve.

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2.4 Limit Positions
The sensor adapter with lock-gate function can assume two limit positions (service or process
position).
Service Position
• Piston is in the upper cylinder position.
• Sensor tip is immersed in the rinsing chamber.
• Sensor tip is not in contact with the process medium.
• Sensor can be cleaned under process conditions.
• In the service position, the sensor can be cleaned by adding a rinse medium to the rinsing cham-
ber. When using the Unical 9000 electro-pneumatic controller, a pH sensor can be calibrated by
adding calibration fluid.
Process Position
• Piston is in the lower cylinder position.
• Sensor tip is retracted from the rinsing chamber.
• Sensor tip is in contact with the process medium.
• Process parameters can be measured.
Service position Process position

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3 Installation
3.1 Inlet and Outlet Hose: Installation
NOTICE! Drinking water may be contaminated by rinse and process media when connecting to
drinking water pipes. Observe the information contained in EN1717. Install a suitable check valve
(e.g.,check valveRV01) at the water or rinse connection. ➜Accessories, p. 29
Note: The inlet hose is white, the outlet hose is red.
Without Cap
1 2
3
4
5
6
01. Loosen the screw(4) and push the inlet hose DN6(3) fully into the opening (1).
02. Tighten the screw (4).
03. Repeat steps 01 and 02 for screw (6) and outlet hose DN6(5) in opening (2).

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With Cap
When using the ARD75 with a protective cap, the inlet and outlet hose from the sensor adapter to the
cap is already installed.
4
6
1 2 3
5
01. Screw the inlet hose DN6(3) with joining piece(4) fully into the opening (1).
02. Tighten the joining piece(4) with an open-end wrench A/F 17.
03. Repeat steps 01 and 02 for outlet hose DN6(5) with joining piece(6) in opening (2).

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3.2 Drive Medium: Installation
Note: The connection hose of the drive medium for moving to the process position is yellow, for the
service position green.
Without Cap
1 2 3 4
1
2
P S
01. Loosen the screws (1) and pull out the holder (2) as far as the back stop. Raise slightly if necessary.
02. Fully push in the process drive medium hose (3) and the service drive medium hose (4).
03. Push the holder (2) as far as the front stop.
04. Tighten the screws (1).

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With Cap
When using the ARD75 with a protective cap, the drive medium connection hoses from the sensor
adapter to the protective cap are already installed.
4
1 2
3
01. Unscrew the coupling nut(1) with ferrule1).
02. Fully push in the coupling nut(1) with hose (3) for connection of the process medium.
03. Fasten the coupling nut(1) finger tight.
04. Repeat steps 01 to 03 for coupling nut(2) with ferrule and hose(4).
1) Not shown.

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4 Commissioning
WARNING! If the sensor adapter is damaged or improperly installed, process medium, poten-
tially containing hazardous substances, may escape. Follow the safety instructions. ➜Safety, p. 4
01. Install the inlet and outlet hose. ➜Inlet and Outlet Hose: Installation, p. 9
02. Install the drive medium hoses. ➜Drive Medium: Installation, p. 11
03. Install the sensor. ➜Installing and Removing Sensors, p. 17
04. Install the sensor adapter with lock-gate function in ARD75.
➜Installing and Removing the Sensor Adapter, p. 15
05. Test for leaks.
✓The ARD75 with sensor adapter is ready for operation.

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5 Operation
5.1 Moving into the Service and Process Position
WARNING! Process or rinse medium can leak from the sensor adapter and may contain
hazardous substances. Only move the sensor adapter into the process position if a sensor is installed.
➜Installing and Removing Sensors, p. 17
Moving into the process or service position may be differently triggered, depending on the installation
of the ARD75 and the sensor adapter with lock-gate function.
Moving into Process Position
Moving into the process positions is triggered by pressurization with drive medium. The hose marked
yellow is pressurized. The hose marked green is depressurized.
Process
01. Install the sensor. ➜Installing and Removing Sensors, p. 17
02. Move the ARD75 into the PROCESS position.
✓Sensor tip is in the process.
Moving into Service Position
Moving into the service position is triggered by pressurization with drive medium. The hose marked
green is pressurized. The hose marked yellow is depressurized.
Service
01. Move the ARD75 into the SERVICE position.
✓Sensor tip is in the rinsing chamber.

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5.2 Installing and Removing the Sensor Adapter
WARNING! Process media may contain hazardous substances: Rinse and clean the ARD75 after
removing it from the process medium. Follow the safety instructions. ➜Safety, p. 4
CAUTION! Risk of cutting injuries from broken sensor glass. Handle the sensor with care.
The sensor adapter can be installed and removed both via the process-side and ambient-side opening
of the ARD75 fitting tube.
Note: Only installation and removal of the sensor adapter via the process-side opening of the ARD75
fitting tube is set out here.
Installation
1
2
3
4 5
6 7
01. Loosen the coupling nut(1) of the ARD75 by ¼ to ½ a turn.
02. Pull the hoses(4) and(5) for the process and service connection through the fitting tube(3) of the
ARD75.
03. Install the process and service connection. ➜Drive Medium: Installation, p. 11
04. Pull the hoses(6) and(7) for the inlet and outlet hose through the fitting tube(3) of the ARD75.
05. Install the inlet and outlet hose. ➜Inlet and Outlet Hose: Installation, p. 10
06. Pull the sensor cable through the fitting tube (3) of the ARD75.
07. Install the sensor. ➜Installing and Removing Sensors, p. 17
08. Connect the sensor cable to the sensor.
09. Push in the sensor adapter(2) up into the fitting tube(3) of the ARD75 as far as the coupling nut
stop.
10. Fasten the coupling nut(1) finger tight.

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Removal
1
2 3
4 5
6 7
01. Loosen the coupling nut(2) of the ARD75 by ¼ to ½ a turn.
02. Pull out the sensor adapter(3).
03. Disconnect the sensor cablefrom the sensor.
04. Remove the sensor. ➜Installing and Removing Sensors, p. 17
05. Pull the sensor cable out through the fitting tube (1) of the ARD75.
06. Uninstall the inlet and outlet hose. ➜Inlet and Outlet Hose: Installation, p. 10
07. Pull the hoses(6) and(7) for the inlet and outlet hose out through the fitting tube(3) of the
ARD75.
08. Uninstall the process and service connection. ➜Drive Medium: Installation, p. 11
09. Pull the hoses(4) and(5) for the process and service connection out through the fitting tube(3) of
the ARD75.

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5.3 Installing and Removing Sensors
WARNING! Process media may contain hazardous substances: Rinse and clean the ARD75 after
removing it from the process medium. Follow the safety instructions. ➜Safety, p. 4
CAUTION! Risk of cutting injuries from broken sensor glass. Handle the sensor with care.
Follow the safety instructions in the sensor manufacturer’s documentation.
Sensor Installation
1
2
3
4 5
6
7
01. Move the sensor adapter(1) into the service position.
➜Moving into the Service and Process Position, p. 14
02. Remove the sensor adapter (1) from the fitting tube of the ARD75 and, if necessary, rinse it off.
➜Installing and Removing the Sensor Adapter, p. 15
03. Check the washer(4) and O‑ring(5) of the sensor(3) for correct positioning and damage, and
replace them if necessary.
04. Push the sensor(3) into the sensor adapter(1).
05. Hold the sensor holder(2) (A/F 24) with a suitable tool and tighten the sensor head(7) (A/F 19)
with 1…3 Nm. Recommended tool: Sensor spanning wrench ZU0647 ➜Accessories, p. 29
06. Guide the sensor cable through the fitting tube of the ARD75.
07. Fit the sensor cable(6) on the sensor(3), and if necessary close the bayonet coupling by turning.
Note: The arc length of the sensor cable must be sufficient to allow the cable to move freely during
the stroke movement of the sensor adapter.

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Sensor Removal
1
2 3
4
5
6
7
01. Move the sensor adapter(1) into the service position.
➜Moving into the Service and Process Position, p. 14
02. Remove the sensor adapter (1) from the fitting tube of the ARD75 and, if necessary, rinse it off.
➜Installing and Removing the Sensor Adapter, p. 15
03. Disconnect the sensor cable(6) from the sensor(4).
04. Hold the sensor holder(5) (A/F 24) with a suitable tool and loosen the sensor head(7) (A/F 19).
Recommended tool: Sensor spanning wrench ZU0647. ➜Accessories, p. 29
05. Pull the sensor(4) out of the sensor adapter(1).
06. Check the compression ring(2) and O‑ring(3) on the sensor(4) for presence and damage, and
replace them if necessary.
07. If the sensor glass is broken, check the immersion tube seal for damage and replace it if necessary.

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5.4 Cleaning and Rinsing the Sensor
Note: Only clean or rinse the sensor while in the service position, when the sensor adapter is sealed
from the process.
1 2
01. Move the sensor adapter into the service position.
➜Moving into the Service and Process Position, p. 14
02. Supply the cleaning or rinse medium to the sensor adapter via the inlet hose(1).
03. Perform cleaning or rinsing in line with operational requirements.
04. Move into the process position. ➜Moving into the Service and Process Position, p. 14
Note: Always keep the outlet hose(2) open.

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6 Maintenance
6.1 Inspection and Maintenance
6.1.1 Inspection and Maintenance Intervals
NOTICE! Different process conditions (e.g., pressure, temperature, chemically aggressive media) will
affect the inspection and maintenance intervals. Analyze the specific application and process condi-
tions at hand. Define appropriate intervals based on similar application cases where experience has
already been gained.
Interval1) Work required
First inspection after a few days/
weeks
Move the sensor adapter into the service position and observe the outlet. If the
product is not tight, process medium will escape from the outlet hose.
➜Troubleshooting, p. 27
As necessary, replace process-wetted and dynamically loaded O-rings.
➜Replacing the O-Rings, p. 25
After 6 – 12 months2) Repeat the measures implemented during the first inspection.
After 10,000 – 20,000 strokes Replacing the process-wetted and dynamically loaded O-rings is recommended.
➜Replacing the O-Rings, p. 25
After approx. 2 years In particular if using chemically aggressive cleaning agents, check the rinse-
wetted gaskets and replace them if necessary. ➜Replacing the O-Rings, p. 25
Maintenance of the dynamically loaded O-ring by re-greasing
➜Replacing the O-Rings, p. 25
1) The stated intervals are recommendations based on Knick’s experience. The actual intervals are dependent on the
specific application for which the sensor adapter is used.
2) Following successful first inspection and confirmation of the suitability of all materials used, the interval may be
lengthened.