Koehler K23900 Guide

operation and instruction manual
K23900
Kinematic Viscosity Bath
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K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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CERTIFICATE OF CONFORMANCE
Kinematic Viscosity Bath
K23900
This certificate verifies that part numbers K23900, Kinematic Viscosity Bath, was manufactured in conformance with the
applicable standards set forth in this certification.
Specifications: ASTM D445
ASTM D2170
ASTM D6074
ASTM D6158
IP 71
ISO 3104
DIN 51550
FTM 791-305
NF T 60-100
This unit is tested before it leaves the factory, to ensure total functionality and compliance to the above specifications
and ASTM standards. Test and inspection records are on file for verification.
Vincent Colantuoni
Product Manager
Koehler Instrument Company, Inc.
1595 Sycamore Ave.
Bohemia, NY 11716
United States of America
Serial Number: ________________________
Date: ________________________________

K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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Table of Contents
1. Introduction 2
1.1. Koehler’s Commitment to Our Customers 2
1.2. Recommended Resources and Publications 2
1.3. Instrument Specifications 3
2. Safety Information and Warnings 3
3. Getting Started 3
3.1. Packing List 3
3.2. Unpacking 3
3.3. Setup 4
4. Descriptions 5
4.1. Instrument Controls 5
4.2. Accessories for Running Tests 6
4.3. Temperature Controller Operation 8
4.4. Recommended Accessories 9
5. Operation 9
5.1. Bath 9
5.2. Power 10
5.3. Starting a Test 10
6. Safety Features 11
6.1. Over-Temperature Protection 11
6.2. Low Fluid Level Protection 11
7. Maintenance 11
7.1. Routine Maintenance 11
7.2. Bath Cleaning 11
7.3. Draining / Changing Bath Medium 12
7.4. Replacement Parts 12
8. Troubleshooting 12
8.1. Unit does not power up 12
8.2. Unit is on but bath dose not heat up 12
8.3. Bath heats up but temperature does not stabilize 12
9. Service 13
10. Storage 13
11. Disposal 13
12.1 General Recycling Information 13
12.2. Disposal Information 13
12. Warranty 14
13. Returned Goods Policy 14
Notes 17

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1. Introduction
The Koehler K23900 Kinematic Viscosity System maintains constant fluid level with up to 7 viscometers. Separate boost and
control heaters allow quick heating to setpoint temperature and fine bath temperature control. Internal stirrer and baffling assure
uniform bath temperature distribution. The K23900 complies with ASTM D445 temperature stability and uniformity requirements.
This manual provides important information regarding safety, technical reference, installation requirements, operating condition
specifications, user facility resource requirements, and operating instructions for the Kinematic Viscosity Instrument. This
manual should also be used in conjunction with applicable published laboratory procedures. Information on these procedures is
given in section 1.2.
1.1. Koehler’s Commitment to Our Customers
Providing quality testing instrumentation and technical support services for research and testing laboratories has been our
specialty for almost 100 years. At Koehler, the primary focus of our business is providing you with the full support of your laboratory
testing needs. Our products are backed by our staff of technically knowledgeable, trained specialists who are experienced in both
petroleum products testing and instrument service to better understand your requirements and provide you with the best solutions.
You can depend on Koehler for a full range of accurate and reliable instrumentation as well as support for your laboratory testing
programs. Please do not hesitate to contact us at any time with your inquiries about equipment, tests, or technical support.
Toll Free: 1-800-878-9070 (US only)
Tel: [phone]
Fax: [phone]
Email: [email protected]
http://www.koehlerinstrument.com
1.2. Recommended Resources and
Publications
1. American Society for Testing and Materials (ASTM)
100 Barr Harbor Drive
WestConshohocken,Pennsylvania19428-2959, USA
Tel: [phone]
Fax: [phone]
http://www.astm.org
email: [email protected]
ASTM Publication:
•ASTM D445: Kinematic Viscosity of Transparent and
Opaque Liquids (and the Calculation of Dynamic
Viscosity)
•ASTM D2170: Kinematic Viscosity of Asphalts
(Bitumens)
•ASTM D6074: Standard Guide for Characterizing
Hydrocarbon Lubricant Base Oils
•ASTM D6158: Standard Specification for Mineral
Hydraulic Oils
2. International Organization for Standardization (ISO)
1, rue de Varembé
Case postale 56
CH-1211 Geneva 20, Switzerland
Tel: [phone]
Fax: [phone]
http://www.iso.org
ISO Publication:
•ISO 3104: Petroleum products –Transparent and
opaque liquids –Determination of kinematic
viscosity and calculation of dynamic viscosity
3. Energy Institute (IP)
61 New Cavendish Street
London, WIM 8AR, United Kingdom
Tel: [phone]
Fax: [phone]
http://www.energyinstpubs.org.uk/
IP Publication:
•IP 71: Kinematic viscosity and calculation of dynamic
viscosity
•IP 319: Kinematic viscosity of bitumens
4. Deutsche International Norm (DIN)
http://www.din.de
DIN Publication:
•DIN 51550: Determination of Kinematic Viscosity and
Dynamic Viscosity
5. Federal Test Method (FTM)
FTM Publication:
•FTM 791-305: Kinematic Viscosity of Petroleum
Products

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6. Association Française de Normalisation (AFNOR)
http://www.afnor.fr
AFNOR Publication:
•NF T 60-100: Kinematic Viscosity of Petroleum
Products
1.3. Instrument Specifications
2. Safety Information and Warnings
Safety Considerations. The use of this equipment may involve hazardous materials and operations. This manual does not purport
to address all of the safety problems associated with the use of this equipment. It is the responsibility of any user of this equipment
to investigate, research, and establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
Equipment Modifications and Replacement Parts. Any modification or alteration of this equipment from that of factory
specifications is NOT recommended and will void the manufacturer warranty, product safety, performance specifications, and/or
certifications whether specified or implied, and may result in personal injury and/or property loss. Replacement parts must be
O.E.M. exact replacement equipment.
Models:
K23900
Electrical Requirements:
115VAC/12A –240VAC/6A,
50/60Hz
Temperature Range:
20 -105°C (68 - 221°F)
Setpoint Temperature:
Display Resolution: +/-0.1°C.
Adjustment Range: 20°C-105°C.
Bath Temperature:
Display resolution: +/-0.01⁰C
Display accuracy: +/-0.02⁰C after calibration
Bath stability: +/-0.02⁰C min/max
Bath uniformity: +/-0.02⁰C relative to set-point temperature
Viscometer Ports:
Seven (7) Round 2” (51mm) ports
Capacity:
Seven (7) Glass Capillary Viscometers
Bath Medium:
Silicone oil with a viscosity less than or equal to 10 cSt at
bath operating temperature and with flash point greater than
bath operating temperature.
NOTE: For best results, it is highly recommended to use
Silicone Oil offered by Koehler Instrument, Part Number
355-001-007 or 355-001-008.
Bath Medium Capacity:
21.6 L (5.7 gal)
Altitude:
Rated for use below 2000m
Environmental Conditions:
As per section 1.4.1 of IEC 61010
Unit Dimensions:
(HxWxD)
24.4 x 15.4 x 17.2 in.
62.0 x 39.1 x 43.7 cm.
72 lb / 33 kg

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Unit Design. This equipment is specifically designed for use in accordance with the applicable standard test methods listed in
section 1.2 of this manual. The use of this equipment in accordance with any other test procedures, or for any other purpose, is
not recommended and may be extremely hazardous.
Over Temperature Protection. This unit is equipped with Over Temperature Protection (OTP), which shuts the heaters and stirrer
motor off to prevent over-heating. Allow the bath to cool down, correct the cause of the problem, and reset the power to return to
normal operation.
Low Fluid Level Protection. This unit is equipped with Low Fluid Level Protection (LFL) to prevent operation with an insufficient
volume of bath medium. Fill the bath to the proper level and reset the power to the unit to return to normal operation.
Chemical Reagents Information. Chemicals and reagents used in performing the test may exhibit potential hazards. Any user
must be familiarized with the possible dangers before use. We also recommend consulting the Material Data and Safety Sheet
(MSDS) on each chemical reagent for additional information. MSDS information can be easily located on the internet at
http://siri.uvm.edu or http://www.sigma-aldrich.com.
3. Getting Started
The instructions for preparing the equipment assume that the user is aware of the contents of this document, which lists the
warranty conditions and important precautions.
3.1. Packing List
•K23900 Kinematic Viscosity Bath with 115V or 220V Line Cord
•Round Viscometer Port Cover (7)
•K23900 Kinematic Viscosity Bath Operation and Instruction Manual
3.2. Unpacking
1. Check labeling for correct orientation of instrument. (e.g. This Side Up)
2. Carefully open top of box with box cutter and remove packing foam.
3. Make two additional vertical cuts, using box cutter, along length of two sides of the box and remove packing foam.
4. Extract instrument and place on suitable cart for transportation to work area / lab bench.
WARNING: Be sure two or more individuals are available for extracting and lifting instrument from box to cart and from cart
to bench. Individuals must lift in accordance to proper technique. See Figure below.
5. Lift instrument from cart and place on bench.
6. Ensure that all parts listed on the packing list are present. Inspect the unit and all accessories for damage. If any damage is
found, keep all packing materials and immediately report the damage to the carrier. We will assist you with your claim, if
requested. When submitting a claim for shipping damage, request that the carrier inspect the shipping container and
equipment. Do not return goods to Koehler without written authorization.

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3.3. Setup
Equipment Placement: Make sure the instrument in placed on a firm, level table in an area with adequate ventilation. The location
must be free of drafts. The unit may be leveled by making minor turning adjustments to the feet located at the base of the unit.
Please note that Koehler does not supply a level with this equipment.
WARNING: Certain mechanical stresses applied to the tempered glass front panel pose a hazard to personnel. Impacts
during normal operation can shatter the glass components releasing the bath fluid posing thermal burn hazards and slipping
hazards. For this reason, the instrument must be operated by and accessible only to trained and authorized personnel and located
in an area where this type of impact is likely to occur.
Environmental Conditions: The instrument environment must comply with the following conditions for proper setup:
•No / Low Dust
•No direct sunlight
•Not near heating or AC ventilation ducts
•No Vibrations
•Clearance from other instruments
•Temperature Range: 5 to 40°C
•Elevation to 2000 meters
•Relative Humidity: < 80%
Ventilation. A ventillation system is required when operating the unit. Flammable vapors and/or steam are generated during
operation and must not be permitted to accumulate.
Power: Connect the line cords to properly fused and grounded receptacles with the correct voltage as indicated in section 1.3 or
on the back of the unit.
WARNING: For safety, disconnect the power when performing any maintenance and/or cleaning. Do NOT turn the power
on unless the bath is filled with the proper medium; otherwise, damage may occur to the unit and the warranty will be void. This
bath is equipped with a low fluid protection feature to prevent damage, but caution should always be exercised.

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4. Descriptions
4.1. Instrument Controls
Figure 1: Instrument Descriptions
1. Bath Temperature Display: The display will show the bath temperature for the duration of use.
2. Lamp Switch. This switch controls turning ON/OFF the lamp for illuminating the test samples.
3. Temperature Controller. The temperature controller regulates the bath temperature for the test procedure. Refer
to Section 4.3 for full operational details.
4. Thermometer/Thermocouple Port: This port allows for independent temperature measurement of the bath
temperature with a thermometer or a Pt-100 RTD probe for precise temperature measurements and digital
temperature controller calibration. If the controller needs to be calibrated, then please contact the Koehler technical
service department.
5. Viscometer Ports: The viscometer, once engaged into the assembly, is placed into the bath through the viscometer
ports on top of the instrument.
7
2
3
4
5
6
1
8
9
10

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6. Bath/ Bath Stirrer: The stirrer constantly circulates bath medium to prevent temperature gradients and ensures
temperature stability. When cleaning and/or servicing, please be sure to disconnect unit power to avoid possible
injury.
7. Power Switch. This switch controls the power to the entire unit. When the power switch is in the ON position, the
digital temperature controller, and the stirrer are powered on.
8. Drain Valve: This ¼” Male NPT valve is used to drain the bath for fluid replacement, cleaning, or storage.
9. Overflow Outlet: The ½” OD Non-Barbed Push on overflow outlet prevents overfilling of the bath and will drain any
excess fluid.
10. Chiller Connections: These two ¼” Female NPT connections allow for the connection of an external chilling
device.
4.2. Accessories for Running Tests
Glass Capillary Viscometer Tubes for K23900
Koehler offers a full selection of glass capillary kinematic viscometers, which are ordered separately from the K23900
instrument, for measuring kinematic viscosity of liquid products as per ASTM D445 and related standard test methods. All
types of viscometers conform to ASTM D445 and related methods for glass capillary kinematic viscometers. All viscometers
with part numbers for the automatic test are listed below. The constant for each individual viscometer is written on the
Certificate of Calibration, included in the packaging.
IMPORTANT: It is recommended when using a newviscometer for the first time to run a test with suitable standard. Different
locations may result in a slightly different constant.
Cannon®-Fenske Routine Viscometers
The Cannon®-Fenske Routine viscometer is a rugged and inexpensive viscometer that works well if the sample is transparent or
translucent.
•For kinematic viscosity of transparent liquids up to 20,000cSt.
•Requires a sample of approximately 7mL.
Cannon®-Fenske Opaque Viscometers
The reverse flow viscometers are designed for testing opaque liquids. These viscometers wet the timing section of the
viscometer capillary only during the actual measurement and must be cleaned, dried and refilled before a repeat
measurement can be made. By contrast, other viscometer types commonly used to measure transparent liquids allow the
sample to be repeatedly drawn up into the capillary, permitting duplicate measurements.
•For measurement of transparent and dark liquids having kinematic viscosities of up to 20,000cSt
•Requires a sample of approximately 12mL.
Ubbelohde Viscometers
Ubbelohde viscometers measure transparent liquids, and unlike the Cannon®-Fenske Routine viscometers, they maintain
the same viscometer constant at all temperatures. This is advantageous when samples are to be measured at different
temperatures.
•Suspended-level type viscometers are for transparent liquids of up to 100,000cSt
•Requires a sample volume of approximately 11mL.

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Cannon-Fenske Routine Viscometers
Cannon-Fenske Opaque Viscometers
Part Number
Size
Approximate
Constant,
cSt/s
Kinematic
Viscosity
Range, cSt
Part Number
Size
Approximate
Constant,
cSt/s
Kinematic
Viscosity
Range, cSt
378-025-C01
25
0.002
0.5 to 2
378-025-C02
25
0.002
0.4 to 2
378-050-C01
50
0.004
0.8 to 4
378-050-C02
50
0.004
0.8 to 4
378-075-C01
75
0.008
1.6 to 8
378-075-C02
75
0.008
1.6 to 8
378-100-C01
100
0.015
3 to 15
378-100-C02
100
0.015
3 to 15
378-150-C01
150
0.035
7 to 35
378-150-C02
150
0.035
7 to 35
378-200-C01
200
0.1
20 to 100
378-200-C02
200
0.1
20 to 100
378-300-C01
300
0.25
50 to 250
378-300-C02
300
0.25
50 to 250
378-350-C01
350
0.5
100 to 500
378-350-C02
350
0.5
100 to 500
378-400-C01
400
1.2
240 to 1,200
378-400-C02
400
1.2
240 to 1,200
378-450-C01
450
2.5
500 to 2,500
378-450-C02
450
2.5
500 to 2,500
378-500-C01
500
8
1,600 to 8,000
378-500-C02
500
8
1,600 to 8,000
378-600-C01
600
20
4,000 to 20,000
378-600-C02
600
20
4,000 to 20,000
378-650-C01
650
45
9,000 to 45,000
378-650-C02
650
45
9,000 to 45,000
378-700-C01
700
100
20,000 to
100,000
378-700-C02
700
100
20,000 to
100,000
Ubbelohde Viscometers
Part Number
Size
Approximate
Constant,
cSt/s
Kinematic
Viscosity
Range, cSt
Part Number
Size
Approximate
Constant,
cSt/s
Kinematic
Viscosity
Range, cSt
378-000-C03
0
0.001
0.3 to 1
378-02B-C03
2B
0.5
100 to 500
378-00C-C03
0C
0.003
0.6 to 3
378-003-C03
3
1
200 to 1,000
378-00B-C03
0B
0.005
1 to 5
378-03C-C03
3C
3
600 to 3,000
378-001-C03
1
0.01
2 to 10
378-03B-C03
3B
5
1,000 to 5,000
378-01C-C03
1C
0.03
6 to 30
378-004-C03
4
10
2,000 to 10,000
378-01B-C03
1B
0.05
10 to 50
378-04C-C03
4C
30
6,000 to 30,000
378-002-C03
2
0.1
20 to 100
378-04B-C03
4B
50
10,000 to
50,000
378-02C-C03
2C
0.3
60 to 300
378-005-C03
5
100
20,000 to
100,000
Viscometer Holders
Koehler offers a wide range of viscometer holders for use with the K23900. The correct holder must be used with the
corresponding viscometer tube for proper operation:
Viscometer Tube Type
Corresponding Holder
Cannon®-Fenske Routine
Cannon®-Fenske Opaque
K23381
Ubbelohde
BS/U-Tube
K23382

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4.3. Temperature Controller Operation
Figure 2. Temperature Controller and LCD Temperature Display
1. Set Point Temperature Display. The upper red LED display shows the set point temperature of the controller.
2. Actual Temperature Display. The LCD display shows the actual bath temperature.
3. Control Buttons.
a. Up Key. Used to increase the set point temperature and to increase or change parameters when programming
temperature controller.
b. Down Key. Used to decrease the set point temperature and to decrease or change parameters when programming
temperature controller.
c. PGM Key. Permits scrolling through controller menu parameters.
d. Exit Key. This key is used to return the temperature controller to the home page when scrolling through menu
parameters. IMPORTANT NOTE: The digital temperature controller for the unit comes pre-programmed from the
Koehler factory. Please do NOT attempt to re-program the digital temperature controller as this will void the product
warranty. If assistance is required, please do not hesitate to contact the Koehler technical service department.
Setting the Temperature. Set the desired operating temperature by adjusting the set point with the up and down keys. The
set point will be displayed in the red LED display and the actual temperature will be displayed on the Bath Temperature
LCD. Please allow the unit to fully equilibrate before proceeding with the test.
Temperature Calibration and Offset. Bath temperature readings are calibrated at 40°C and 100°C prior to shipment, and
the bath can be calibrated at 20°C, 40°C, 60°C, 80°C or 100°C. The temperature offsets at these calibration temperatures
are stored in temperature controller parameters “C20”, “C40”, “C60”, “C80” and “C100”, respectively. When turned on or
when setpoint temperature is changed, the bath automatically determines what offset value is needed to correct bath
temperature readings based on the selected set point temperature and programmed calibration offsets and loads it into the
temperature controller’s “OFFS” temperature offset parameter. When needed, the calibration temperature offsets can be
adjusted in 0.01°C increments using following steps:
a. Press PGM button on temperature controller to enter program mode and press PGM button again to enter user program
mode. Lower line on temperature controller’s display will change from “StPt” to “USEr” to “dPnt”.
1.
3a.
3b.
3c.
3d.
2.

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b. Press PGM button to program the “dPnt” parameter –“dPnt” will flash on lower line.
c. Press Up Arrow button to increase parameter setting from 1 to 2 to change the display to 2 decimal places. After a few
seconds, “dPnt” will stop flashing indicating that setting was saved.
d. Press Down Arrow button as many times as needed to scroll down to the first calibration parameter “C20”, “C40”, “C60”,
“C80” or “C100” to be programmed.
e. Press PGM button to program the selected parameter - “C20”, “C40”, “C60”, “C80” or “C100” will flash on lower line.
f. Press Up or Down Arrow buttons to increase or decrease calibration offset to the desired value or press EXIT button to
leave value as is. After a few seconds, “C20”, “C40”, “C60”, “C80” or “C100” will stop flashing indicating that value was
saved.
g. Repeat steps 4, 5, and 6 to program the next calibration parameter in sequence or skip to next step when done
programming these parameters.
h. Press Up Arrow button as many times as needed to scroll back up to decimal point parameter “dPnt” and press PGM
button to reprogram this parameter –“dPnt will flash on lower line.
i. Press Down Arrow button to decrease parameter setting from 2 to 1 to return display to 1 decimal place. After a few
seconds, “dPnt” will stop flashing indicating that setting was saved.
j. Press EXIT button twice to exit from programming mode. The bath will now use the programmed calibration offsets to
correct the bath temperatures displayed by the bath readout LCD.
4.4. Recommended Accessories
Withdrawal Bulb (K22090)
Used to pull sample into viscometer tube.
Rubber Stopper (K23311)
Used to plug viscometer tube and hold up sample prior to testing.
Operation near or below ambient temperatures. A water supply or external chiller may be used to maintain the temperature of
the bath for cooler set point temperature. A chiller must be used when the set point temperature is less than 10°C above the
ambient temperature. Set the chiller to 10°C below the set point. Connections for water or refrigerated coolant are located at the
back of the bath. There are two connections: inlet and outlet. The hose connections can be secured with the appropriate fittings
as required to prevent the tubing from disengaging from the connection.
5. Operation
5.1. Bath
Fill the bath with the Koehler recommended heat transfer fluid. Fill the bath with the medium from the top through one of the seven
port openings using a wide neck funnel to the bottom of the 3 Philips head screws on the tank baffle.
NOTE: Do not attempt moving the bath when filled with fluid
medium. Drain all fluid before moving or relocating the instrument. See
section 7.2 of this document. Sudden starting and stopping could result in
hot bath fluid being forcefully ejected from the bath. It could also result in
overbalancing and tipping over the instrument.
NOTE: Do not drain the bath until the fluid is at ambient temperature.
Testing
Temperature
Recommended Fluid
20 - 105°C
Koehler Instrument supplies a clear
silicone heat transfer fluid, 10cSt at
25°C with high oxidation resistance
and low volatility. CAS # 63148-62-
9. Minimum Flash Point: 200°C
(392°F).
(Part # 355-001-007 (1 gal) and #
355-001-008 (5 gal))

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NOTE: Do not use bath fluids that will decompose or volatilize producing flammable vapors below the maximum instrument
operating temperature +25°C.
NOTE: Coloration of the Silicon Bath Oil is an indication that the Medium must be changed. See Draining instructions in section
7.3 of this document. When a decision is made to discard this material, dispose of this material and its container to a hazardous
of special waste collection point. Country, State, or local laws may impose additional regulatory requirements regarding disposal.
Dispose in accordance to all applicable regulations.
WARNING: Bath oils contaminated with light ends can pose a flammability hazard.
5.2. Power
Turn on the main power switch to the unit.
WARNING: Do NOT turn the power on unless the bath is filled with the proper medium; otherwise, damage may occur to
the unit and the warranty would be void. This bath is equipped with a low fluid protection feature to prevent damage, but caution
should always be exercised.
5.3. Starting a Test
Before running a test, make sure the unit is level. Otherwise, the results will be affected.
1. Set the desired operation temperature using the temperature control (See Section 4.3).
2. Install viscometer into its viscometer holder. Carefully slide the holder onto the top of the tube:
Figure 3. Viscometer and viscometer holder
3. Charge the viscometer with sample and carefully lower into the bath through the viscometer ports.
WARNING: Do not test or run materials that boil or exhibit high vapor pressure at the bath test temperature.
IMPORTANT: Allow the bath AND the sample enough time to reach the temperature before starting measurements. Allow 30
minutes for the bath to equilibrate. The LCD display will indicate when the bath temperature is stable. Do not add medium to the
bath while a test is being performed. Additional medium will disrupt the temperature equilibrium of the bath and cause
erroneous test results.

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6. Safety Features
The Koehler K23900 Kinematic Viscosity System is equipped with several safety and protection features, which are described in
the following sections.
WARNING: The bath is NOT Explosion Proof.
6.1. Over-Temperature Protection
The Koehler K23900 Kinematic Viscosity System is equipped with Over-temperature Protection (OTP) circuitry, which prevents
the unit from exceeding 115°C. If the unit cannot maintain the set point temperature and begins to decline, the OTP circuitry may
have been activated (“High Bath Temp” will display on the LCD). Please follow these steps.
1. Turn off the unit power switch and disconnect the line cord.
2. Determine the source of the problem and correct the situation.
3. Restart the unit. Monitor the operations to ensure that the unit is operating properly. If you are still experiencing trouble, please
contact Koehler technical service for assistance.
6.2. Low Fluid Level Protection
The Koehler K23900 Kinematic Viscosity System is equipped with Low Fluid Level Protection circuitry, which prevents the unit
from operating with an insufficient volume of fluid. If this protection is activated (“Low Bath Level” will display on the LCD), turn off
the main power, fill the bath with a sufficient amount of fluid and turn it back on again.
7. Maintenance
WARNING: Disconnect power to the unit before servicing and accessing any internal portion of the instrument to avoid
exposure to high voltages and/or temperatures which may result in personal injury or death. If you have any questions about
maintaining your equipment, then please do not hesitate to contact the Koehler technical service department.
7.1. Routine Maintenance
The K23900 Kinematic Viscosity System requires little routine maintenance to provide many years of continuous service. However,
over the course of time, some instrument parts may need to be replaced. When ordering replacement part(s), please provide the
model number, serial number, and product shipment date of your equipment so that we can ensure you will receive the proper
replacement part(s).Replacement Parts
7.2. Bath Cleaning
•To clean the instrument’s exterior, which includes all painted surfaces and glass, either a solution of soap and water or
laboratory grade detergent may be used.
•Apply cleaner to clean wipe or cloth, not to the instrument directly. Wipe surface clean.
•Do Not clean bath exterior with organic chemicals such as Acetone, Toluene, Hexane, etc.
•For more difficult cleaning of finished surfaces, a dilute solution or isopropanol in water may be used.
•It is not recommended that more aggressive solvents be used on painted surfaces since paint color will tarnish or be
stripped from the instrument.
•Stainless Steel surfaces may be cleaned using a more aggressive solvent such as a stainless steel cleaner.
•Glass surfaces may be cleaned using a more aggressive solvent such as acetone, if necessary.

K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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SHOCK AND BURN HAZARD: Only clean inside the bath when equipment is de-energized and unplugged from the
mains power supply. Allow adequate time for heating coils to completely cool before cleaning.
7.3. Draining / Changing Bath Medium
WARNING: Do not begin draining the bath medium until it has reached ambient temperature.
NOTE: When a decision is made to discard this material, dispose of this material and its container to a hazardous of special waste
collection point. Country, State, or local laws may impose additional regulatory requirements regarding disposal. Dispose in
accordance with all applicable regulations.
1. Drain the bath by opening the Bath Drain Valve.
2. Once fully drained, be sure to close the Bath Drain Valve to avoid spillage on next use of the bath.
7.4. Replacement Parts
8. Troubleshooting
WARNING: Troubleshooting procedures involve working with high voltages and/or temperatures which may result in
personal injury or death, and should only be performed by trained personnel. Please do not hesitate to contact Koehler for
assistance.
8.1. Unit does not power up
•Establish that the socket outlet is providing proper and adequate voltage.
•Check if line switch is in the ON position.
•The Line Switch functions as acircuit breaker and a power switch. If the breaker is tripped, thepower switch
will be in the OFF position
•If problem persists, please call the Koehler technical service department for assistance.
8.2. Unit is on but bath dose not heat up
•Make sure that the actual temperature reading is not higher than the set-point temperature.
•Determine if the bath fluid level is too low as the Low Fluid Level Protection (LFL) may be activated
Determine if the Overtemperature Protection (OTP) circuitry has been activated.
8.3. Bath heats up but temperature does not stabilize
•Make sure that the actual temperature reading is not higher than the set-point temperature.
•Determine if the temperature controller is properly calibrated by comparison to an ASTM standard thermometer.
Part Number
Replacement Part
K23900-03237
Outer Shell Glass Window
282-016-025
115VAC Line Cord
282-018-027
230VAC Line Cord
275-103-046
Temperature Controller, 110-
240V

K23900 Kinematic Viscosity Bath
Operation and Instruction Manual
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9. Service
Under normal operating conditions and with routine maintenance, the K23900 Kinematic Viscosity System should not require
service. Any service problem can be quickly resolved by contacting Koehler’s technical service department either by letter, phone,
fax, or email. In order to assure the fastest possible service, please provide us with the following information.
Model Number: ________________________
Serial Number: ________________________
Date of Shipment: ______________________
10.Storage
This laboratory test instrument is equipped with electrical components. Storage facilities should be consistent with an indoor
laboratory environment. This testing equipment should not be subjected to extremes of temperature and/or moisture.
This equipment was shipped from the factory in a corrugated cardboard container. If long term storage is anticipated, re-packing
the instrument in a water-resistant container is recommended to ensure equipment safety and longevity.
11.Disposal
12.1 General Recycling Information
•No refrigerants or pressurized materials.
•No charged capacitors or components that could electrically discharge.
•No components such as springs or spring powered gears that could store mechanical energy.
•No chemical hazards from any components.
•No radiation is emitted from any components.
12.2. Disposal Information
The K23900 Kinematic Viscosity Bath is subject to the WEEE directive. Once the instrument has reached the end of its useful life,
the instrument and or its components must be recycled or disposed of in accordance to Country, State, or local laws that may
impose regulatory requirements regarding disposal. Dispose instrument and/or components in accordance to all applicable
regulations.
The K23900 is composed of the following major components and materials:
NOTE: There are No Refrigerants or Hazardous Materials contained in any component.
Major Component
Material
Instrument Housing
Powder Coated, Cold-Rolled
Carbon Steel 18
Tank / Bath Cover
Stainless Steel, #316
Bath Window
Soda Lime Glass
Motor
Copper Windings
Heater Coils
Inconel