Isotech 17702W Operating instructions

Page 1 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (12–01/18)
HEATPIPE FURNACE
FOR MODELS
17702W 17702P 17702S
User Maintenance Manual/Handbook
Isothermal Technology Limited, Pine Grove, Southport, PR9 9AG, England
Tel: [phone] Fax: [phone] Internet: www.isotech.co.uk E-mail: [email protected]
The company is always willing to give technical advice and assistance where appropriate. Equally, because of the programme of
continual development and improvement we reserve the right to amend or alter characteristics and design without prior notice.
This publication is for information only.

Page 2 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
GUARANTEE
ⓒIsothermal Technology Limited
This instrument has been manufactured to exacting standards and is guaranteed for twelve months against
electrical break-down or mechanical failure caused through defective material or workmanship, provided
the failure is not the result of misuse.
In the event of failure covered by this guarantee, the instrument must be returned, carriage paid, to the
supplier for examination and will be replaced or repaired at our option.
FRAGILE CERAMIC AND/OR GLASS PARTS ARE NOT COVERED BY THIS GUARANTEE
INTERFERENCE WITH OR FAILURE TO PROPERLY MAINTAIN THIS INSTRUMENT MAY INVALIDATE
THIS GUARANTEE
The company is always willing to give technical advice and assistance where appropriate. Equally,
because of the programme of continual development and improvement we reserve the right to amend or
alter characteristics and design without prior notice. This publication is for information only.
This handbook contains information that has been reproduced with the kind permission of Eurotherm. Such
data is subject to the following notice.
Isothermal Technology Limited
Pine Grove, Southport, Merseyside, PR9 9AG, England
Telephone: [phone]/544611 / Fax: [phone]
Email: [e-mail] / Website: www.isotech.co.uk

Page 3 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
CONTENTS
EMC INFORMATION........................................................................................................................................... 5
ELECTRICAL SAFETY........................................................................................................................................ 5
HEALTH AND SAFETY INSTRUCTIONS ................................................................................................................... 6
UNPACKING................................................................................................................................................................ 7
INSTALLATION OF THE THERMOMETER SUPPORT (REMOVED FOR TRANSIT)........................................... 8
SAFETY ....................................................................................................................................................................... 9
CAUTIONARY NOTE............................................................................................................................................... 9
THIS EQUIPMENT MUST BE EARTHED................................................................................................................ 9
FUSE AND NEUTRAL LINK REPLACEMENT ........................................................................................................ 9
GENERAL LAYOUT................................................................................................................................................... 10
INTRODUCTION........................................................................................................................................................ 12
THE HEATPIPE FURNACES .................................................................................................................................... 13
MODEL 17702W .................................................................................................................................................... 13
MODEL 17702P ..................................................................................................................................................... 13
MODEL 17702S ..................................................................................................................................................... 13
USING THE OVERTEMPERATURE CONTROLLER ............................................................................................... 14
QUICK START........................................................................................................................................................... 15
USING THE CONTROLLER...................................................................................................................................... 16
How to log in as the SUPERVISOR:................................................................................................................... 17
How to log in as the Engineer:............................................................................................................................ 17
The Isotech splashscreen and controls: ............................................................................................................. 18
Principle of operation.......................................................................................................................................... 19
Changing the Set Point....................................................................................................................................... 19
To change the Setpoint of the equipment:.......................................................................................................... 19
How to globally change from °C to °F or Kelvin:................................................................................................. 19
PROCESS TO APPLY A USER LINEARIZATION TO THE HEATPIPE FURNACE............................................. 20
Enabling the AUTOTUNE feature:...................................................................................................................... 21
How to change the Date and Time or the Language of the equipment:............................................................. 21
To change the DATE and TIME or LANGUAGE: ............................................................................................... 22
The NETWORK INTERFACE:............................................................................................................................ 22
To access the NETWORK INTERFACE:............................................................................................................ 22
Data Logging:...................................................................................................................................................... 22
FTP Server Archiving:......................................................................................................................................... 23
PROGRAMMER Function:.................................................................................................................................. 23
To create, install and run a PROGRAM via the controller interface please follow the instructions below: ........ 24
PROGRAM Details: ............................................................................................................................................ 24
How to create a simple PROGRAM using the controller interface:.................................................................... 25
To enable/RUN this PROGRAM:........................................................................................................................ 26
To edit an existing PROGRAM:.......................................................................................................................... 26
Using the HOLDBACK feature:........................................................................................................................... 27
CONNECTING THE FURNACE TO A LIQUID COOLANT SUPPLY (NOT REQUIRED FOR MODEL 17702W).... 28
CALIBRATION APPARATUS FOR ZINC, ALUMINIUM AND SILVER FIXED POINTS ........................................... 29
GENERAL ASSEMBLY OF FIXED POINT CELL INSIDE THE HEATPIPE.......................................................... 29
INTRODUCTION.................................................................................................................................................... 29
DESCRIPTION....................................................................................................................................................... 29
METHOD OF OPERATION.................................................................................................................................... 30
CALIBRATION APPARATUS FOR ALUMINIUM, SILVER AND COPPER FIXED POINTS .................................... 31
INTRODUCTION.................................................................................................................................................... 31
DESCRIPTION....................................................................................................................................................... 31
METHOD OF OPERATION.................................................................................................................................... 31
CALIBRATION APPARATUS FOR INDIUM AND TIN FIXED POINTS.................................................................... 32
INTRODUCTION.................................................................................................................................................... 32
DESCRIPTION....................................................................................................................................................... 32
METHOD OF OPERATION.................................................................................................................................... 32
ELIMINATING CONTAMINATION DURING THE CALIBRATION OF HIGH TEMPERATURE THERMOMETERS 33
CELL HANDLING....................................................................................................................................................... 34
CELL KIT................................................................................................................................................................ 34
THERMOMETRIC FIXED POINTS; A TUTORIAL .................................................................................................... 38

Page 4 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
DEFINING FIXED POINTS AND RELATED DATA................................................................................................... 40
GENERAL NOTE ON ISOTECH METAL FREEZE POINT CELLS........................................................................... 41
PRECAUTIONS TO PREVENT DEVITRIFICATION OF QUARTZ ENVELOPES.................................................... 42
GENERAL COMMENT .............................................................................................................................................. 43
SEALED METAL FREEZING POINT CELL............................................................................................................... 44
SEALED METAL FREEZING POINT CELL BODY DIMENSIONS ........................................................................... 45
ACKNOWLEDGEMENT............................................................................................................................................. 46
ISOTECH I-CAL EASY .............................................................................................................................................. 47
PROGRAM EDITOR .............................................................................................................................................. 47
REVIEW.................................................................................................................................................................. 48

Page 5 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
EMC INFORMATION
This product meets the requirements of the European Directive on Electromagnetic Compatibility (EMC)
89/336/EEC as amended by EC Directive 92/31/EEC and the European Low Voltage Directive 73/25/EEC,
amended by 93/68/EEC. To ensure emission compliance please ensure that any serial communications
connecting leads are fully screened.
The product meets the susceptibility requirements of EN 50082-1, criterion B.
Symbol Identification
Publication
Description
ISO3864
Caution (refer to manual)
IEC 417
Caution, Hot Surface
ELECTRICAL SAFETY
This equipment must be correctly earthed.
This equipment is a Class 1 Appliance. A protective earth is used to ensure the conductive parts cannot
become live in the event of a failure of the insulation.
The protective conductor of the flexible mains cable which is coloured green/yellow MUST be connected to
a suitable earth.
The Blue conductor should be connected to Neutral and the Brown conductor to Live (Line).
Warning: Internal mains voltage hazard. Do not remove the panels.
There are no user serviceable parts inside. Contact your nearest Isotech agent for repair.
Voltage transients on the supply must not exceed 2.5kV.
Conductive pollution, e.g. Carbon dust, must be excluded from the apparatus. EN61010 pollution degree 2.

Page 6 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
HEALTH AND SAFETY INSTRUCTIONS
1. Read this entire manual before use.
2. Wear appropriate protective clothing.
3. Operators of this equipment should be adequately trained in the handling of hot and cold items and
liquids.
4. Do not use the apparatus for jobs other than those for which it was designed, i.e. the calibration of
thermometers.
5. Do not handle the apparatus when it is hot (or cold), unless wearing the appropriate protective
clothing and having the necessary training.
6. Do not drill, modify or otherwise change the shape of the apparatus.
7. Do not dismantle the apparatus.
8. Do not use the apparatus outside its recommended temperature range.
9. If cased, do not return the apparatus to the carrying case until the unit has cooled.
10. There are no user serviceable parts inside. Contact your nearest Isotech agent for repair.
11. Ensure materials, especially flammable materials are kept away from hot parts of the apparatus, to
prevent fire risk.
12. Ensure adequate ventilation when using oils at high temperatures.

Page 7 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
UNPACKING
EVERY EFFORT HAS BEEN MADE TO PACKAGE THIS UNIT FOR TRANSPORT AND TO ENSURE ITS
GOOD CONDITION ON ARRIVAL AT ITS DESTINATION.
BEFORE COMMISSIONING IT IS NECESSARY TO REMOVE THE FURNACE CORE TRANSIT CLAMP.
TO AVOID DAMAGE PLEASE FOLLOW INSTRUCTIONS:
1. Slacken the central nut using the required tube spanner; the insertion of a screwdriver through the
tube spanner will prevent the central stud turning.
2. Remove the 3 screws securing the transit clamp to the top of the unit. Slacken each screw by
degrees equally.
3. Gently lift the transit clamp vertically; the attached tube and rubber securing block will thereby be
extracted from the furnace core.
4. Normal commissioning procedure may now be followed.
5. Keep the transit clamp and use it if the furnace is ever transported.

Page 8 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
INSTALLATION OF THE THERMOMETER SUPPORT (REMOVED FOR
TRANSIT)
This furnace is supplied with the thermometer support for the safe storage of up to four thermometers, but
removed for transit purposes. Please see the below image for a guide to the installation of the support to
the furnace.
1. Thermometer support
2. Screw locations
Please screw the thermometer support to the furnace in the way shown above using the screws supplied.
Tighten sufficiently.
Please take care when inserting or removing thermometers from the pocket below the support.

Page 9 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
SAFETY
CAUTIONARY NOTE
Products of Isothermal Technology Ltd are intended for technically trained and competent personnel
familiar with good laboratory practice. It is expected that personnel using this equipment will be
knowledgeable and skilful in the management of apparatus which may be under power or under extremes
of temperature (molten metals, cryogenic liquids, etc.) and will appreciate the hazards which may be
associated with, and the precautions to be taken with, such equipment.
THIS EQUIPMENT MUST BE EARTHED
The furnace is supplied with a fuse carrier fitted with a neutral link. This is clearly labelled and is for use
with a mains system with a neutral line, such as the UK supply. If the furnace is to be used on a system
where both supply lines are live with respect to earth then the neutral fuse link should be replaced with a
fuse. A spare fuse is supplied with the furnace.
FUSE AND NEUTRAL LINK REPLACEMENT
Hazardous voltages are exposed when the rear furnace panel is removed. Before removing the panel, you
must isolate the furnace from the electrical supply. To replace the main electrical fuse or to replace the
neutral link bar it is necessary to remove the rear panel; see warning above. The panel will become free
after the four corner screws are removed.
The fuse holders will be seen at the lower right-hand side of the cabinet. The left-hand fuse holder will
always contain a fuse. The right-hand fuse holder will leave Isotech with a neutral shorting bar, they are
clearly labelled. As explained elsewhere, if your local supply does not have a neutral line but has both lines
live with respect to earth this link should be replaced with a fuse and the holder labelled to this effect.
The top half of the fuse carrier lifts from the lower body.

Page 10 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
GENERAL LAYOUT
Front View
1. USB socket
2. Ethernet socket
3. Main controller
4. Overtemperature controller
5. Mains power on switch
Top View
1. Heatpipe furnace
2. Pre-warming pocket

Page 11 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
Rear View
1. Cooling coil connection (not on W
version)
2. Cooling coil connection (not on W
version)
3. Mains Power cable

Page 12 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
INTRODUCTION
•Essentially Gradient Free
•Heat pipe Operation from Indium to Copper
•Simple Use - no zone offsets to adjust
Isotech metrology furnaces have more than 35 years of proven use and are widely used by the worlds’
leading NMIs. For the optimal use of fixed point cells, the temperature uniformity should be less than 10mK
over the length of the fixed point sample CCT/2000-13, “Optimal Realization of the Defining Points of the
ITS-90...”
Isotech heat pipe furnaces offer essentially gradient free operation; heat pipes provide the ideal conditions
for the creation and maintenance of ITS-90 fixed point cells. Unlike some other companies Isotech can
provide heat pipe furnaces to suit Indium, Tin, Zinc, Aluminium, Silver and Copper fixed points.
Plateau length is determined by the difference in temperature between the heat pipe and cell - this can be
adjusted to give a plateau of any length of up to tens of hours. Our controllers offer extra resolution and
allow adjustment to 0.1°C right up to 1100°C. The Potassium and Sodium models have a cooling coil in the
lid with connections to circulate tap water to keep the furnace lid cool protecting the SPRT and reducing
heat load into the lab. A pre-warming tube with a temperature approximately equal to that of the heat pipe
made of a unique, gas-tight material is provided to heat the SPRT prior to it being placed in a cell. The
furnaces feature an adjustable, independent over temperature device to protect expensive cells and SPRTs
as well as a second internal over temperature safety device.

Page 13 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
THE HEATPIPE FURNACES
MODEL 17702W
Contains a water heat pipe with a range from 125°C to 250°C, this encompassing the fixed points of indium
and tin.
MODEL 17702P
Contains a potassium heat pipe with a temperature range from 400°C to 1000°C, thus encompassing zinc,
aluminium and silver freeze points.
MODEL 17702S
Contains a sodium heat pipe with a temperature range from 450°C to 1100°C, thus constituting a facility for
aluminium, silver, gold and copper freeze point measurements.

Page 14 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
USING THE OVERTEMPERATURE CONTROLLER
The furnace uses an alarm value on the controller to disable the heaters if the furnace goes into the alarm
condition. If the furnace goes into the alarm condition, it will power down the Main controller and circuitry.
Adjusting the Overtemperature value on the controller:
1. Press the Scroll button to display A1 HI
2. Use the up/down buttons to scroll to the desired alarm setting. This would normally be 10-20°C
above the target temperature
3. To enter the value you will need to press the PAGE and SCROLL buttons simultaneously
4. To re-set the controller from an alarm condition you will need to press the buttons again
simultaneously
5. If the controller is in the alarm condition and the complete furnace is powered down, the controller
will “remember” the condition and will still need to be manually reset when powered up again

Page 15 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
QUICK START
Locate the furnace in a suitable, level location. Leave a minimum of 150mm of space around and 500mm
above the furnace for air circulation. Ensure there is a suitable water supply or circulation system for the
cooling of the furnace (see page 28) and power supply nearby.
Assemble the furnace as on page 29, ensure the coolant is connected as in on page 28 and the equipment
has a suitable electrical connection as on page 9. Connect the furnace to the electrical supply and power it
up.
The Overtemperature controllers will power up and display the current temperature.
To power up the Heatpipe furnace you will need to enable the controller. To do this, press the SCROLL
button on the Overtemperature controller until Hi Alarm is displayed, using the up/down buttons enter a new
temperature for the overtemperature protection. Initially this can be quite a low value, say 500°C*, for test
purposes. Now press the SCROLL and PAGE buttons together, once to enter the new value and a second
time to reset the controller. On the second press the furnace will make a noise as the control circuit powers
up.
The furnace is now active and ready for use. On the controller, press the SCROLL button to highlight the
Setpoint box. Press again to adjust the value and select a suitable value, a value 20°C below the
overtemperature is suitable, using the up/down buttons. Enter the value by pressing the Scroll button. The
furnace will now rise in temperature to the selected value.
If the furnace has been in transit or not been used for several days then there may be an ingress of
moisture into the insulation and other ceramics, the furnace may need to be “dried out” by running at a low
value such as 400/450°C** for a period of several hours.
*100°C for W version
** 150°C for W version

Page 16 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
USING THE CONTROLLER
The controller installed on this equipment uses an advanced three loop controller with a multi-channel
sensor input.
Other features of the controller are:
•Built in data logging
•Ethernet connection
•USB host for controller updates and data export
•Bright colour display
•Dynamic optimisation of the control PID parameters
•Eight point zone linearization for Main and Annealing furnace
•Built in Programmer, supports 100 programs, each of 25 segments
Before using the controller, please read this manual thoroughly to get the best performance from the
equipment.
Certain features used in this controller require different levels of access. The Operator access requires no
passcode to use. These functions include:
•Changing the setpoint
•Changing any values using the USER ACCESS PAGE
Other features will require the user to log in as “Supervisor” to carry out these functions. These include:
•Adjusting the PID settings
•Using the Programmer function
•Changing the linearity settings
•Extracting data from the recorder function
Configuration changes to the controller require you log in as “Engineer” to perform these functions. These
include:
•Change language selection
•Change °C to °F or K
•Change equipment clock and time zone

Page 17 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
How to log in as the SUPERVISOR:
1. Press the Page button to display the Home menu
2. Scroll to LOG IN
3. Press the SCROLL button
4. Press up to scroll to SUPERVISOR in dialogue box
5. Press the SCROLL button to prompt for a passcode
6. Select code 15 from the soft keyboard
7. Press PAGE button to prompt to accept the changes
8. Select Yes and enter with SCROLL button to display the SUPERVISOR screen (as above)
9. When logged in as the SUPERVISOR the equipment will control in the normal way
How to log in as the Engineer:
1. Press the Page button to display the Home menu
2. Scroll to LOG IN
3. Press the SCROLL button
4. Press up to scroll to ENGINEER in dialogue box
5. Press the SCROLL button to prompt for a passcode
6. Select code 17 from the soft keyboard
7. Press PAGE button to prompt to accept the changes
8. Select Yes and enter with SCROLL button to display the ENGINEER screen
9. When logged in as the ENGINEER, the equipment will not control the temperature of the heat
source

Page 18 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
The Isotech splashscreen and controls:
The USER INTERFACE start up screen and controls:
1. ISOTECH splashscreen
2. PAGE button
3. SCROLL button
4. DOWN button
5. UP button
The HOME page:
1. Heatpipe temperature
2. Heatpipe setpoint
3. Setpoint adjust box
4. Data Record icon
5. PAGE button
6. SCROLL button
7. DOWN button
8. UP button
The USER ACCESS page:
1. Heatpipe autotune feature
2. IP type (toggle between fixed and DHCP)
3. PB adjust
4. TI adjust
5. TD adjust
6. Controller filter time adjust
7. Global UNITS adjustment

Page 19 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
Principle of operation
The principle of the operation of heat pipes is as follows. The inside walls of the inner and outer tubes are
covered with a fine wire mesh screen. When heated, the small amount of sodium with which the heat pipe
is charged vaporises throughout the interior cavity and condenses on the walls of the cavity. Assuming that
the interior is isobaric, the vapour-liquid transition at the walls is a thermal equilibrium condition which can
only occur at constant temperature. The condensed liquid is returned to the bottom of the structure (for re-
vaporisation) by capillary action at the mesh screen.
In order to prolong the life of the heat-pipe it is necessary to control the rate of temperature increase while
the sodium is in its solid phase. The controller has been programmed automatically to ramp the heat-pipe
temperature at a controlled rate until it approaches 450°C for Sodium, 400°C for Potassium, at which
temperature the medium can be considered molten and the temperature is then allowed to rise at the full
rate.
The controller uses internal alarm features to determine the point which the controlled ramp terminates and
is used to control the ramp rate. These parameters are set at 445(°C) for Sodium and 395(°C) for
Potassium and 7.5(°C/min) and should not be changed.
Changing the Set Point
The main controller will control the Heatpipe furnace. The setpoint is accessible from the Home page of the
controller. The controller circuit will be enabled/disabled by the overtemperature controller on the right of
the main controller.
The Heatpipe furnace set point will adjust the main heatpipe temperature.
To compensate for any errors in the linearity of the display temperature, the user can adjust the linearity
using the 8 point adjustment curve for each furnace. See section below for details on how to do this.
To change the Setpoint of the equipment:
1. From the ISOTECH homepage, press the SCROLL button once, this will highlight the SETPOINT
ADJUST box.
2. Press the SCROLL button once more and this will allow adjustment of the setpoint via the
UP/DOWN buttons.
3. Scroll to the desired set point as described above.
4. When the temperature is set, press the SCROLL button again to enter and save the setting.
5. The equipment will now raise or lower the furnace temperature as required.
How to globally change from °C to °F or Kelvin:
1. Log in as the Engineer
2. Scroll to INSTRUMENT
3. Scroll to DISPLAY
4. Scroll to UNITS
5. Select by pressing the Scroll button
6. Use up/down to select from °C, °F or Kelvin
7. Press the Page button to exit and save the selection

Page 20 of 48
Heatpipe Furnace Models 17702W, 17702P, 17702S (13–07/20)
PROCESS TO APPLY A USER LINEARIZATION TO THE HEATPIPE FURNACE
From time to time the control sensors inside the furnace will need to be adjusted as the sensor drifts with
time and use at high temperature. The controller has the capability to compensate for these errors using
an eight point correction curve. This will need to be regularly checked for errors and can easily be
corrected within the controller using the following procedure.
The image below illustrates a simplified graphical view of the process.
Isotech standard offset values are set at the following temperatures:
This is listed as Channel 1 on the controller
17702S
17702P
17702W
450°C
420°C
125°C
660°C
660°C
156°C
960°C
960°C
230°C
1080°C
---
---
Non populated points are unused as standard.
Please follow the procedure below to linearise the controller display value:
1. For the heatpipe furnace, set the furnace up as it will be used with a fixed point cell using either a
cell or a simulation of the cell using a thermally efficient metal block suitable for use over the
temperature range (Inconel 600 would be ideal)
2. Place a reference thermometer inside the cell
3. Set the furnace to the lowest useable temperature (recommendation would be to use the
temperatures listed above)
4. Allow the system the thermally stabilise
5. Press the PAGE button to enter the SUPERVISOR menu
6. Scroll to the CHANNELS tab and enter with the SCROLL button
7. Select CHANNEL 1
8. Scroll to the ISOTECH tab and enter with the SCROLL button
9. Scroll to CAL STATUS and enter with the SCROLL button
10. Scroll to POINT 1 and enter the value from the reference thermometer
The controller is now ready to accept a value. Ensure the equipment is thermally stable, you will now need
to use the temperature value displayed by the reference thermometer.