Fluke Micro-Bath 7102 User manual

7102
Micro-Bath
User’s Guide
2013 Rev. 1, 2/22
©2013-2022 Fluke Corporation. All rights reserved. Specifications are subject to change without notice.

LIMITED WARRANTY AND LIMITATION OF LIABILITY
Each Fluke product is warranted to be free from defects in material and workmanship under normal use and
service. The warranty period is one year and begins on the date of shipment. Parts, product repairs, and services
are warranted for 90 days. This warranty extends only to the original buyer or end-user customer of a Fluke
authorized reseller, and does not apply to fuses, disposable batteries, or to any product which, in Fluke's opinion,
has been misused, altered, neglected, contaminated, or damaged by accident or abnormal conditions of operation
or handling. Fluke warrants that software will operate substantially in accordance with its functional specifications
for 90 days and that it has been properly recorded on non-defective media. Fluke does not warrant that software
will be error free or operate without interruption.
Fluke authorized resellers shall extend this warranty on new and unused products to end-user customers only but
have no authority to extend a greater or different warranty on behalf of Fluke. Warranty support is available only if
product is purchased through a Fluke authorized sales outlet or Buyer has paid the applicable international price.
Fluke reserves the right to invoice Buyer for importation costs of repair/replacement parts when product purchased
in one country is submitted for repair in another country.
Fluke's warranty obligation is limited, at Fluke's option, to refund of the purchase price, free of charge repair, or
replacement of a defective product which is returned to a Fluke authorized service center within the warranty
period.
To obtain warranty service, contact your nearest Fluke authorized service center to obtain return authorization
information, then send the product to that service center, with a description of the difficulty, postage and insurance
prepaid (FOB Destination). Fluke assumes no risk for damage in transit. Following warranty repair, the product will
be returned to Buyer, transportation prepaid (FOB Destination). If Fluke determines that failure was caused by
neglect, misuse, contamination, alteration, accident, or abnormal condition of operation or handling, including
overvoltage failures caused by use outside the product's specified rating, or normal wear and tear of mechanical
components, Fluke will provide an estimate of repair costs and obtain authorization before commencing the work.
Following repair, the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the
repair and return transportation charges (FOB Shipping Point).
THIS WARRANTY IS BUYER'S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE SHALL NOT BE LIABLE FOR ANY
SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF
DATA, ARISING FROM ANY CAUSE OR THEORY.
Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or limitation
of incidental or consequential damages, the limitations and exclusions of this warranty may not apply to every
buyer. If any provision of this Warranty is held invalid or unenforceable by a court or other decision-maker of
competent jurisdiction, such holding will not affect the validity or enforceability of any other provision.
11/99
Fluke Corporation
P.O. Box 9090
Everett, WA 98206-9090
U.S.A.
Fluke Europe B. V.
P.O. Box 1186
5602 BD Eindhoven
The Netherlands

i
Table of Contents
Title Page
Introduction................................................................................................ 1
Safety Information ..................................................................................... 2
Contact Fluke Calibration .......................................................................... 3
Service Information.................................................................................... 3
Specifications ............................................................................................ 4
Environmental Conditions.......................................................................... 5
Quick Start................................................................................................. 5
Unpacking.................................................................................................. 5
Bath Environment ................................................................................. 5
Bath Fluids (Summary) ......................................................................... 6
Installation ................................................................................................. 6
Power ........................................................................................................ 7
Thermal Electric Devices........................................................................... 7
Set the Temperature.................................................................................. 8
Bath Use.................................................................................................... 8
Parts and Controls..................................................................................... 9
Front Panel ........................................................................................... 9
Back Panel............................................................................................ 10
Accessories ............................................................................................... 11
Transport/Pour Access Lid ................................................................... 11
Access Cover (Optional)....................................................................... 12
Probe Basket ........................................................................................ 12
Stir Bar.................................................................................................. 13
Well Extender (Optional)....................................................................... 13
Comparison Calibration ............................................................................. 13
Calibration of Multiple Probes.................................................................... 14
General Operation ..................................................................................... 14
Change Display Units ........................................................................... 14
Bath Fluid.............................................................................................. 14
Temperature Range.............................................................................. 14
Viscosity................................................................................................ 15
Specific Heat......................................................................................... 15
Thermal Conductivity ............................................................................ 15
Thermal Expansion............................................................................... 15
Electrical Resistivity .............................................................................. 15

7102
User’s Guide
ii
Fluid Lifetime ........................................................................................ 15
Safety ................................................................................................... 16
Cost ...................................................................................................... 16
Commonly Used Fluids......................................................................... 16
Mineral Oil.......................................................................................... 16
Silicone Oil (Dow Corning 200.05, 200.10, 200.20)........................... 16
Fluid Characteristics Charts.................................................................. 17
Limitations and Disclaimer ................................................................. 18
About the Graph................................................................................. 19
Stirring ....................................................................................................... 19
Fluid Drain ................................................................................................. 20
Temperature Controller ............................................................................. 20
Controller Operation .................................................................................. 20
Well Temperature...................................................................................... 21
Temperature Set-point .............................................................................. 21
Programmable Set-points..................................................................... 21
Set-point Value ..................................................................................... 21
Temperature Scale Units...................................................................... 23
Scan .......................................................................................................... 23
Scan Control......................................................................................... 23
Scan Rate............................................................................................. 24
Temperature Display Hold......................................................................... 24
Mode Setting ........................................................................................ 25
Switch Wiring........................................................................................ 25
Switch Test Example ............................................................................ 25
Secondary Menu ....................................................................................... 26
Thermal Electric Device (TED).................................................................. 26
Proportional Band...................................................................................... 26
Controller Configuration ............................................................................ 27
Operating Parameters .......................................................................... 27
High Limit ........................................................................................... 27
Stir Speed .......................................................................................... 28
Serial Interface Parameters.................................................................. 28
BAUD Rate ........................................................................................ 28
Sample Period ................................................................................... 28
Duplex Mode...................................................................................... 29
Linefeed ............................................................................................. 29
Calibration Parameters......................................................................... 29
R0 ...................................................................................................... 30
ALPHA ............................................................................................... 30
DELTA ............................................................................................... 30
C0 and CG ......................................................................................... 30
rCAL................................................................................................... 30
Digital Communication Interface ............................................................... 30
Serial Communications ............................................................................. 31
Wiring ................................................................................................... 31
Setup .................................................................................................... 31
Serial Operation.................................................................................... 31
Interface Commands ................................................................................. 31
Calibrate a Single Probe ........................................................................... 33

Micro-Bath
iii
Stabilization and Accuracy ........................................................................ 34
Calibration ................................................................................................. 34
Calibration Points ...................................................................................... 34
Calibration Procedure................................................................................ 35
Compute DELTA................................................................................... 35
Compute R0 & ALPHA ......................................................................... 36
Accuracy and Repeatability .................................................................. 36
Maintenance .............................................................................................. 36
Troubleshooting Problems, Possible Causes, and Solutions.................... 37

7102
User’s Guide
iv

1
Introduction
The Fluke Calibration 7102 Micro-Bath (the Product, calibrator, or instrument) is a portable instrument/
bench-top temperature calibrator. Use the Product to calibrate thermocouple and RTD temperature
probes. The Product is small enough to use in the field, and accurate enough to use in the lab. With an
ambient temperature of 23 °C (74 °F), calibrate over a range of −5 °C to 125 °C (23 °F to 257 °F). The
resolution of the display is 0.01 degrees.
The Product features:
• Convenient handle
• RS-232 interface
• Universal ac input (115 VAC or 230 VAC)
• Optional well extender to extend well depth
Built in programmable features include:
• Temperature scan rate control
• Temperature switch hold
• Eight Set-point memory
• Adjustable readout in °C or °F
The temperature is accurately controlled by a hybrid analog/digital controller. The controller uses a
precision platinum RTD as a sensor and controls the well temperature with a solid-state relay (triac)
driven heater.
The LED front panel (display) continuously shows the current well temperature. Set the temperature
with the control keys to any desired temperature within the specified range. Multiple fault protection
devices ensure user and Product safety and protection.
Through proper use, the Product continuously provides accurate calibration of temperature sensors
and devices.

7102
User’s Guide
2
Safety Information
General Safety Information is in the printed Safety Information document that shipped with the Product.
It can also be found online at www.Flukecal.com.More specific safety information is listed in this
manual where applicable.
A Warning identifies conditions and procedures that are dangerous to the user. A Caution identifies
conditions and procedures that can cause damage to the Product or the device under test (DUT).
WCautions
To avoid possible damage to the Product, follow these guidelines:
• Never introduce any foreign material into the well.
• Do not change the values of the calibration constants from the factory set values. The
correct setting of these parameters is important to the safety and proper operation of
the unit.
• Do not slam the probe stems into the well. This type of action can cause a shock to
the sensor and affect the calibration.
• Always use a ground fault interrupt device.
• The unit is a precision instrument. Although it has optimum durability and trouble-
free operation, it must be handled with care.
• Most probes have handle temperature limits. Be sure that the probe handle
temperature limit is not exceeded in the air above the instrument.
• The instrument and any thermometer probes used with it are sensitive instruments
that can be easily damaged. Always handle these devices with care. Do not allow
them to be dropped, struck, stressed, or overheated.
• When you calibrate PRTs always follow correct calibration procedure and calibrate
from high temperatures to low temperatures with the appropriate triple point of water
checks.
• Components and heater lifetimes can be shortened by continuous high temperature
operation.

Micro-Bath
Contact Fluke Calibration
3
• If a mains supply power fluctuation occurs, immediately turn off the bath. Power
bumps from brown-outs and black-outs can damage the instrument. Wait until the
power has stabilized before re-energizing the bath.
• Fluke Calibration does not recommend the use of water as a fluid in the Product. If the
tank coating is compromised, galvanic corrosion will occur due to dissimilar metals
and the presence of water (electrolyte).
Note
Disregard any references to the use of water as a bath fluid in this manual.
Contact Fluke Calibration
Fluke Corporation operates worldwide. For local contact information, go to our website:
www.flukecal.com
To register your product, view, print, or download the latest manual or manual supplement, go to our
website.
Fluke Corporation
P.O. Box 9090
Everett, WA 98206-9090
[phone]
[email protected]
Service Information
Contact an authorized Fluke Calibration Service Center if the Product needs calibration or repair during
the warranty period. Please have Product information such as the purchase date and serial number
ready when you schedule a repair.

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User’s Guide
4
Specifications
Table 1. Specifications
Range −5 °C to 125 °C (23 °F to 257 °F)
Accuracy ±0.25 °C
Stability ±0.015 °C at −5 °C (oil, 5010)
±0.03 °C at 121 °C (oil, 5010)
Uniformity ±0.02 °C
Resolution 0.01 °C/F
Operating Temperature 5 °C to 45 °C (41 °F to 113 °F)
Heating Time 25 °C to 100 °C (77 °F to 212 °F): 30 minutes
Cooling Time 25 °C to 0 °C (77 °F to 32 °F): 30 minutes
Well Size 64 x 139 mm deep (2.5 in dia. x 5.5 in)
(access opening is 48 mm [1.9 in] in diameter)
Exterior Dimension 31 cm x 18 cm x 24 cm (12 in H x 7.2 in W x 9.5 in D)
Weight 6.8 kg (15 lb) with fluid
Power 115/230 VAC (±10 %), 50/60 Hz, 300 VA
Fuse Rating T, 4 A, 250 V
Readout Switchable °C or °F
Controller Digital controller with data retention
Thermal Electric Devices (TED) 150 W
Cooling Fan and Thermal Electric Devices (TED)
Environmental Conditions
Ambient Temperature Range 5 °C to 45 °C (41 °F to 113 °F)
Ambient Relative Humidity maximum 80 % for temperature <31 °C, decreasing linearly to 35 % at 45 °C
Altitude <2000 m
Fault Protection Sensor burnout and short protection
Safety
General
Heating
IEC 61010-1: Overvoltage Category II, Pollution Degree 2
IEC 61010-2-010
Electromagnetic Compatibility (EMC)
International.......................IEC 61326-1: Basic Electromagnetic Environment
CISPR 11: Group 1, Class A
Group 1: Equipment has intentionally generated and/or uses conductively-coupled radio
frequency energy that is necessary for the internal function of the equipment itself. Class
A: Equipment is suitable for use in all establishments other than domestic and those
directly connected to a low-voltage power supply network that supplies buildings used for
domestic purposes. There may be potential difficulties in ensuring electromagnetic
compatibility in other environments due to conducted and radiated disturbances. Caution:
This equipment is not intended for use in residential environments and may not provide
adequate protection to radio reception in such environments.
Korea (KCC)....................Class A Equipment (Industrial, Broadcasting,
& Communication Equipment)
Class A: Equipment meets requirements for industrial electromagnetic wave equipment
and the seller or user should take notice of it. This equipment is intended for use in
business environments and not to be used in homes.
USA (FCC) .....................47 CFR 15 subpart B. This product is considered an exempt
device per clause 15.10

Micro-Bath
Environmental Conditions
5
Environmental Conditions
See Safety Information for cautions that deal with environmental conditions. Maintenance and cleaning
recommendations can be found in Maintenance. Vibrations in the calibration environment should be
minimized, see Bath Environment.
Quick Start
WCaution
Read Bath Use before placing the bath in service. Incorrect handling can damage the
Product and void the warranty.
Unpacking
Unpack the Product carefully and inspect it for any damage that may have occurred during shipment. If
there is shipping damage, notify the carrier immediately.
Verify that these components are present:
• 7102 Micro-Bath
• 7102/7103 Safety Information
• Transport/Pour Access Lid
• Probe Basket
•StirBar
• Power Cord
• Report of Calibration
• Calibration Label
• Access Cover, optional
• Well Extender, optional
Bath Environment
Locate the Product in an appropriate environment. Make sure that the location is free of drafts, extreme
temperatures, temperature changes, and contaminates. Place the bath on a heat-proof surface such
as concrete with at least 15 cm (6 in) of clearance around the bath. Beware of the danger of accidental
fluid spills.

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User’s Guide
6
WWarning
To prevent personal injury:
• Be aware that the Product operates at high temperatures.
• Keep all flammable and meltable materials away from the Product.
• Although the Product is well insulated, top surfaces become hot.
• If the bath is operated at high temperatures, use a fume hood to remove any vapors
given off by hot bath fluid.
Bath Fluids (Summary)
The Product does not come with fluid. Various fluids are available from Fluke Calibration and other
sources. To safely operate the Product, only select bath fluids with adequate thermal properties that
meet the application requirements.
Depending on the desired temperature range, any of these fluids, as well as others, can be used:
• Ethylene glycol
• Mineral oil
• Silicone oil
See Bath Fluid and its subsections for information on fluid selection. See the specific MSDS sheet for
each fluid selected.
Installation
WCaution
• Read Bath Use before you place the bath into service. incorrect handling can damage
the Product and void the warranty.
• Do not operate this Product without fluid.
• Make sure that the tank is 3/4 full before you set the temperature.
To install the Product:
1. Remove the access lid from the bath and check the tank for foreign matter (for example, dirt or
remnant packing material). Before you fill the well, thoroughly dry the inside of the well with paper
towels.
2. Plug the power cord into a grounded mains outlet. Observe that the nominal voltage corresponds to
that indicated on the back of the Product.
3. Carefully insert the probe basket into the well, then insert the probe(s) into the basket.
4. With the probe(s) in the well, fill the tank 3/4 full with the appropriate, clean fluid.

Micro-Bath
Power
7
5. Power on the Product. Toggle the switch on the power entry module (PEM), see Figure 2. The fan
blows air through the Product and the display illuminates after 3 seconds. After a brief self test, the
Product begins normal operation. If the Product fails to operate, check the power connection.
6. Heat to the maximum temperature of the fluid. See Set the Temperature.
7. Slowly fill the well to 2.5 cm (1 in) below the top of the basket at the maximum temperature of the
fluid.
WCaution
Be aware that some fluids expand and could overflow the bath if not watched, see Bath
Fluid and its subsections for more information.
The set-point temperature and the number of and size of the probes determine the fluid level. Under-
filling can reduce bath performance. Always keep the fluid level at least 2 cm (0.75 in) below the top
of the well to prevent overflow of the fluid when you insert the probes. For example, if you place
silicone oil 200.05 at room temperature, 25 °C (77 °F), into the bath and heat to 125 °C, this causes
a 2.5 cm (1 in) expansion of the fluid inside the well.
The display shows the well temperature. The well Thermal Electric Devices (TEDs) bring the
temperature of the well to the setpoint temperature. Make sure that the fluid is being stirred.
Power
The ac mains supply provides power to the bath and passes through a filter to prevent the transmission
of switching spikes to other equipment. Refer to Specifications for power details.
When powered on,the display briefly shows a four-digit number. This number indicates the number of
times power was applied to the bath. Also,briefly displayed,is data which indicates the controller
hardware configuration. Use this data in some circumstances for diagnostic purposes.
Thermal Electric Devices
The temperature controller precisely controls the bath power to maintain a constant bath temperature.
Power is controlled by periodically switching the TEDs on for a certain amount of time with power
transistors.

7102
User’s Guide
8
Set the Temperature
Temperature Set-point explains how to set the calibrator temperature set-point with the front panel
keys. Briefly, the procedure is:
1. Push SET twice to access the set-point value.
2. Push UP or DOWN to change the set-point value.
3. Push SET to store the new set-point.
4. Push EXIT to return to the temperature display.
When the set-point temperature changes, the heater switches on or off to raise or lower the
temperature. The well temperature gradually changes until it reaches the set-point temperature. The
well can require 25 minutes to reach the set-point,depending on the span. Another 10 minutes to 15
minutes is required to stabilize within ±0.03 °C of the set-point. Ultimate stability can take 20 minutes to
30 minutes more of stabilization time.
Bath Use
Read this section before you place the bath in service.
The information in this section is for general information only. Do not use this section as the basis for
calibration laboratory procedures. Each laboratory must write their own specific procedures.
Generally, baths are set to one temperature and used to calibrate probes only at that single
temperature. This means that the type of bath fluid does not have to change. Additionally, leave the
bath energized to reduce the stress on the system.
Select the correct fluid for the temperature range of the calibration. You must select bath fluids to
operate safely with adequate thermal properties to meet the application requirements. Be aware that
some fluids expand and could overflow the bath if not watched, see Bath Fluid and its subsections for
information specific to fluid selection and see the MSDS sheet specific to the fluid selected.
WWarning
To prevent possible fire, or personal injury:
• Use care to prevent personal injury or damage to objects. The bath generates extreme
temperatures.
• Carefully place probes on a heat/cold resistant surface or rack until they are at room
temperature. Probes can be extremely hot or cold when removed from the bath.
• Wipe the probe with a clean, soft cloth or paper towel before you insert it into another
bath. This prevents the contamination of fluids from one bath to another.
• Be aware that cleaning the probe can be dangerous if the probe has not cooled to
room temperature. Additionally, high temperature fluids can ignite the paper towels if
the probe has not been cooled.
• Be aware some of the high temperature fluids react violently to water or other liquid
mediums.

Micro-Bath
Parts and Controls
9
If the probe was calibrated in liquid salt, carefully wash the probe in warm water and dry completely
before you transfer it to another fluid. Always be sure that the probe is completely dry before you insert
it into a hot fluid.
For optimum accuracy and stability, allow the bath adequate stabilization time after it reaches the set-
point temperature.
Parts and Controls
This section describes the bath and its parts.
Front Panel
This section describes and shows the front panel. See Figure 1.
Figure 1. 7102 Front Panel
Controller Display (A) – The digital display not only shows set and actual temperatures but also
shows various calibrator functions, settings, and constants. The display shows temperatures in units
according to the selected scale °C or °F.
Controller Keypad (B) – Use the keys (SET, DOWN,UP, and EXIT) to set the calibrator temperature
set-point, access and set other operating parameters, and access and set calibration parameters.
Set the control temperature directly in degrees of the current scale. You can set the temperature to
one-hundredth of a degree Celsius or Fahrenheit.
The functions of the keys are:
SET – Shows the next parameter in the menu and stores parameters to the value.
DOWN – Decrements the shown value of parameters.
UP – Increments the shown value.
EXIT – Exits a function. Any changes made to the value shown are ignored. Hold EXIT for
approximately 0.5 seconds to exit back to the main display.
SET UP
DOWN EXIT
7102
MICRO-BATH –5°C to 125°C
A
B

7102
User’s Guide
10
Back Panel
This section describes and shows the back panel. See Figure 2.
Figure 2. 7102 Back Panel
Power Cord – Underneath the calibrator is the removable power cord inlet that plugs into an IEC
grounded socket (A).
Power Switch (B) – The power switch is on the power entry module (PEM). The PEM also houses the
fuses and the dual voltage selector (most models). The PEM allows most units to be field switchable for
115 VAC ( ±10 %) or 230 VAC ( ±10 %) operation.
Serial Port (C) – Use the DB-9 male connector to interface the calibrator to a computer or terminal
with serial RS-232 communications.
Fan – The fan inside the calibrator runs continuously to cool the Product. Slots at the top and around
the two corners of the calibrator provide airflow. Keep the area around the calibrator clear to allow
adequate ventilation out of the back.
115V
RS-232
DISPLAY
HOLD
23
1

Micro-Bath
Accessories
11
Accessories
Transport/Pour Access Lid
Use the provided transport/pour access lid (see Table 2) to keep the fluid in the bath when transporting.
Table 2. Bath Lids and Lid Parts
Item Description Item Description
APour Spout DTransport/Pour Access Lid
BPour Spout Cover EOptional Access Cover
CTransport Plug FGuide Ring

7102
User’s Guide
12
Access Cover (Optional)
An aluminum access cover (see Table 2) is available for optimum stability. Drill holes into the access
cover to insert the probes into the well. The holes must be within the guide ring for the probes to fit into
the probe basket.
WWarning
Do not install an access cover without holes (like the optional cover) onto a bath that is
energized. Dangerous pressures may result from fluids vaporizing.
Probe Basket
A probe basket (Figure 3) provides a guide for the probes and prevents bumping of the stir bar.
Figure 3. Probe Basket

Micro-Bath
Comparison Calibration
13
Stir Bar
The stir bar (Figure 4) sits in the bottom of the well for mixing the fluid providing better accuracy,
uniformity, and stability.
Figure 4. Stir Bar
Well Extender (Optional)
An optional well extender is available to increase the depth of the well. The extender screws onto the
well and features an O-ring. Thread the extender down until the O-ring makes a good seal. Some fluids
may expand up to 6.35 cm (2.5 in). Therefore, when you use the well extender,keep in mind how much
the fluid in use expands. Do not overfill the well.
Comparison Calibration
Comparison calibration involves testing a probe (Device Under Test, DUT) against a reference probe.
After you insert the DUT into the bath, allow sufficient time for the probes to settle and the temperature
of the bath to stabilize.
One significant benefit of bath use rather than a dry-well to calibrate multiple probes is that the probes
do not need to be identically constructed. The fluid in the bath allows you to calibrate different types of
probes at the same time. However, stem effect from different types of probes is not completely
eliminated. Even though all baths have horizontal and vertical gradients, these gradients are minimized
inside the bath work area. Nevertheless, make sure to insert probes to the same depth in the bath
liquid. Be sure that all probes are inserted deep enough to prevent stem effect. Fluke Calibration
recommends a general rule for immersion depth to reduce the stem effect to a minimum: 20 x the
diameter of the DUT + the sensor length. Do not submerge the probe handles. If the probe handles get
too warm during calibration at high temperatures, use a heat shield just below the probe handle. This
heat shield could be as simple as aluminum foil placed between the probe handle and above the bath
before you insert it in the bath or as complicated as a specially designed reflective metal apparatus.

7102
User’s Guide
14
For best results when you calibrate over a wide temperature range, start at the lowest temperature and
progress to the highest temperature.
Use probe clamps or drill holes in the access cover to hold probes in place. Other fixtures to hold the
probes can be designed. Keep the reference probe and the probe(s) to be calibrated as closely
grouped as possible (while allowing adequate spacing for fluid to pass between the probes) in the
working area. For maximum bath stability, keep the working area covered.
To prepare for calibration:
• Place the reference probe in the bath working area.
• Place the DUT in the bath working area as close as possible to the reference probe.
Calibration of Multiple Probes
Fully loading the bath with probes increases the required probe temperature stabilization. Use the
reference probe as the guide to make sure that the temperature has stabilized before you start the
calibration.
General Operation
Change Display Units
The temperature units are factory defaulted to Celsius. To change to Fahrenheit or back to Celsius:
1. Push SET and UP simultaneously. The temperature display changes units.
2. Push SET three times to store the changes. The display shows:
Un=C
or
1. Push UP or DOWN to change units.
2. Push SET to store the changes.
Bath Fluid
Many fluids work with the Product. When you choose a fluid consider the many important
characteristics of the fluid. Among these are temperature range, viscosity, specific heat, thermal
conductivity, thermal expansion, electrical resistivity, fluid lifetime, safety, and cost. The next sections
explain each of these characteristics in detail.
Temperature Range
An important characteristic to consider is the temperature range of the fluid. Few fluids work well
throughout the complete temperature range of the bath. The bath operating temperature must always
be within the safe and useful temperature range of the fluid. The freeze point of the fluid or the
temperature at which the viscosity becomes too great determines the lower temperature range of the
fluid. The upper temperature is usually limited by vaporization, flammability, or chemical breakdown of
the fluid. Vaporization of the fluid at higher temperatures can affect temperature stability because of
cool condensed fluid that drips into the bath from the lid.