Isotech 465 Operating instructions

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3 Zone Metrological Furnace 465 Iss.13 –11/16
3 ZONE METROLOGICAL
FURNACE MODEL 465
User Maintenance Manual/Handbook
This manual refers to the following cells:
Zinc Freeze-Point Cell
Antimony Freeze-Point Cell
Aluminium Freeze-Point Cell
Silver Freeze-Point Cell
Gold Freeze-Point Cell
Copper Freeze-Point Cell
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.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
CONTENTS
GUARANTEE..................................................................................................................................................3
EMC INFORMATION..............................................................................................................................4
ELECTRICAL SAFETY..............................................................................................................................5
HEALTH AND SAFETY INSTRUCTIONS .........................................................................................................6
CAUTIONARY NOTE .....................................................................................................................................7
THIS EQUIPMENT MUST BE EARTHED..........................................................................................................7
FUSE AND NEUTRAL LINK REPLACEMENT ...................................................................................................7
INTRODUCTION ...........................................................................................................................................8
NEW FEATURES.............................................................................................................................................9
GENERAL LAYOUT ......................................................................................................................................10
CONNECTING THE FURNACE TO A LIQUID COOLANT SUPPLY ..............................................................12
QUICK START ..............................................................................................................................................13
USING THE OVERTEMPERATURE CONTROLLER ........................................................................................14
USING THE CONTROLLER ..........................................................................................................................15
How to log in as the SUPERVISOR: ....................................................................................................................15
How to log in as the Engineer:............................................................................................................................16
The Isotech splashscreen and controls: ..............................................................................................................16
The USER ACCESS page:....................................................................................................................................17
Changing the Set Point ........................................................................................................................................17
To change the Setpoint of the equipment:..........................................................................................................17
How to globally change from °C to °F or Kelvin:................................................................................................18
Process to apply a User linearization to Top, Main and Bottom zone control sensors ......................................18
Enabling the AUTOTUNE feature:.....................................................................................................................20
How to change the Date and Time or the Language of the equipment: ............................................................20
To change the DATE and TIME or LANGUAGE:...............................................................................................20
The NETWORK INTERFACE: ...........................................................................................................................21
To access the NETWORK INTERFACE:............................................................................................................21
Data Logging: ......................................................................................................................................................21
FTP Server Archiving: .........................................................................................................................................22
Programmer Function:........................................................................................................................................22
Program Details: .................................................................................................................................................22
How to create a simple PROGRAM using the controller interface: .................................................................24
To enable/RUN this PROGRAM: ........................................................................................................................24
To edit an existing PROGRAM:...........................................................................................................................25
Using the HOLDBACK feature:..........................................................................................................................25
REALISING THE FOLLOWING FIXED POINTS: TIN, LEAD, ZINC, ANTIMONY, ALUMINIUM, SILVER, GOLD AND COPPER
....................................................................................................................................................................31
FREEZING THE TIN CELL ............................................................................................................................32
A USEFUL HINT ...........................................................................................................................................33
MAINTENANCE ...........................................................................................................................................35
CELL HANDLING .....................................................................................................................................35
CELL KIT ..................................................................................................................................................35
SPARE PARTS ...............................................................................................................................................36
SERVICING THE 3 ZONE METROLOGICAL FURNACE.................................................................................37
THERMOMETRIC FIXED POINTS - A TUTORIAL..........................................................................................38
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
ADDITIONAL SERVICES AND INFORMATION .............................................................................................44
ISOTECH I-CAL EASY ...................................................................................................................................45
PROGRAM EDITOR ......................................................................................................................................45

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3 Zone Metrological Furnace 465 Iss.13 –11/16
GUARANTEE
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
RECOMMENDATION
The life of your ISOTECH Instrument will be prolonged if regular maintenance and cleaning to remove general dust
and debris is carried out.
ISOTHERMAL TECHNOLOGY LTD.
PINE GROVE, SOUTHPORT
PR9 9AG, ENGLAND
TEL: [phone]/544611
FAX: [phone]
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.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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 its 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.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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 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 IT IS NECESSARY TO
REMOVE THE REAR PANEL, SEE WARNING ABOVE. THE PANEL WILL BECOME FREE AFTER THE FOUR
CORNER SCREWS ARE REMOVED.
TWO SPARE FUSES ARE SUPPLIED WITH THE FURNACE.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
INTRODUCTION
Whilst heat pipe furnaces offer the ideal environment to melt and freeze ITS-90 Fixed Points the temperature range is
limited by fluid that flows inside the pipe. Three zone furnaces can offer wider operating ranges and still meet the
requirements for “Optimal Realization of the Defining Points of the ITS-90...” CCT/2000-13. In place of a heat pipe
the Model 465 3 Zone High Temperature Furnace uses top and bottom zone heaters to minimize temperature
gradients.
Widest Operating Range
Three Zone Control
Long Plateau Length
This more recent addition to our long-established range of metrology furnaces offers an alternative for those who
prefer 3-Zone furnaces to heat pipe technology and need high temperature operation. The three zones create a
controlled volume of constant temperature within the furnace in which High-Temperature Fixed Points such as
Aluminium, Silver and Copper can be frozen and melted. Because High-Temperature thermometers can be easily
contaminated by metallic vapours, great care has been taken to eliminate the use of metals throughout the calibration
volume. The cell holder is made of alumina.
A ceramic equalizing block is available comprising a closed ended tube, alumina tubes to house the sensors being
compared, and alumina powder to act as an equalizing media.
This 3-Zone Furnace can be used for the realizations of Zinc, Aluminium, Silver, Gold and Copper points, or with an
optional equalizing block used for annealing or comparison calibration.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
NEW FEATURES
The furnace has been upgraded to benefit from the latest technology. Fitted with a crystal clear colour display the
furnace is now fully programmable. Programs can be created for the furnace to switch between set temperatures, for
example to bring the furnace to the melt or freeze temperature at a desired time, or to lower the furnace
temperature after a predetermined time. The PID control parameters are now dynamically optimized at different
temperatures optimizing furnace stability. An Ethernet interface allows the furnace temperature to be monitored
across a network whilst a USB Interface allows programs to be copied or for the furnace heat up and cool down
history to be exported.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
GENERAL LAYOUT
Figure 1: Front View:
Figure 2: Top View:

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3 Zone Metrological Furnace 465 Iss.13 –11/16
Figure 3: Rear View:

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3 Zone Metrological Furnace 465 Iss.13 –11/16
CONNECTING THE FURNACE TO A LIQUID COOLANT SUPPLY
This furnace has a cooling coil installed on the top panel, this is to allow a cooler top panel working surface that will
prevent a hazard to the user when the furnace is at high temperatures and will also minimise any distortion to the top
panel that may lead to damage caused as a consequence of this. Temperatures in excess of 700°C require the cooling
coil to be used, for temperatures below this value it is optional.
The cooling coil is accessed from the rear panel (Figure 3) and this will need to be removed to make any connections
or service of the connections.
The cooling medium can be any number of substances, but in most cases water will suffice. Isotech would
recommend a cooled re-circulation system for environmental reasons, however, a simple connection to a water tap
will produce the same results. Please seek advice from your local environmental agency before cooling from a tap
supply.
The requirement will be up to 2 litres of liquid/minute. Connections require a tube or pipe with 3/8” internal
diameter for both the input and output. The exiting liquid will never rise above 50°C so a simple PVC piping can be
used.
There is no directional flow and the liquid can be flowed in either direction.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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
(Figure 3) and power supply nearby.
Assemble the furnace as in Figure 12, ensure the coolant is connected as in Page 14 and the equipment has a suitable
electrical connection. Connect the furnace to the electrical supply and power it up.
The Overtemperature controller will power up and display the current temperature of the furnace. To enable the
controller, 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 (Page 12). Initially this can be quite a
low value 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 main control circuit
powers up. The main controller will now boot up, starting with the ISOTECH splashscreen.
The furnace is now active and ready for use. On the main controller, press the SCROLL button to highlight the
Setpoint box (Figure 8). 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 100°C for a
period of several hours.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
USING THE OVERTEMPERATURE CONTROLLER
Figure 4
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.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
USING THE CONTROLLER
The controller installed in 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, Top and Bottom zones
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 (see Figure 9)
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 zone 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
How to log in as the SUPERVISOR:
Figure 5 Figure 6
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 (Figure 6)
9. When logged in as the SUPERVISOR the equipment will control in the normal way

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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
The Isotech splashscreen and controls:
The USER INTERFACE start up screen and controls:
Figure 7
1. ISOTECH splashscreen
2. PAGE button
3. SCROLL button
4. DOWN button
5. UP button
The HOME page:
Figure 8
1. Furnace temperature
2. Furnace setpoint
3. Bottom Zone temperature
4. Setpoint adjust box
5. Top Zone temperature
6. Data Record indication
7. PAGE button
8. SCROLL button
9. DOWN button
10. UP button

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3 Zone Metrological Furnace 465 Iss.13 –11/16
The USER ACCESS page:
Figure 9
1. IP TYPE –Toggles between Fixed IP type and
Dynamic
2. Display units
3. Main Zone Autotune
4. Top Zone Autotune
5. Bottom Zone Autotune
6. Set Point Ramp rate
7. Main Zone Fixed offset
8. Top Zone Offset
9. Bottom Zone Offset
Figure 10
1. Current program NAME/STATUS
2. MODE display
3. Program Edit beacon
4. Block temperature (Process Variable)
5. Program Setpoint
6. Program STATUS
Changing the Set Point
This furnace set point will adjust the main zone temperature. The top and bottom zone will automatically adjust
when the main zone is adjusted. They do not require to be independently adjusted.
To compensate for any errors in the Top and Bottom zone values, the user can adjust the linearity using the 8 point
adjustment curve for each zone. 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.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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
Process to apply a User linearization to Top, Main and Bottom zone control sensors
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.
Figure 11: illustrates a simplified graphical view of the process.
Isotech standard offset values are set at the following temperatures:
1. 230°C
2. 440°C
3. 660°C
4. 880°C
5. 1080°C
Points 6, 7 and 8 are unused.
1. Set the furnace up as it will be used with a fixed point cell using either a cell or a simulation of the cell
2. Set the furnace to the lowest useable temperature (recommendation would be to use the temperatures of
the fixed points from Zinc to Copper)
3. Place a reference thermometer inside the cell at the recommended measurements
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 desired zone from the list as below from and enter with the SCROLL button
a. Channel 1 = Main zone
b. Channel 2 = Top zone
c. Channel 3 = Bottom zone
d. Channel 4 = Unused

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3 Zone Metrological Furnace 465 Iss.13 –11/16
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.
11. Record the value on the reference thermometer and scroll to DISPLAY VALUE tab and press enter
12. This will bring up a soft keyboard, use this keyboard to enter the exact temperature displayed by the
calibrated standard
13. Press the PAGE button to enter the value, the controller will ask you to confirm the settings. Select YES and
enter the value
14. The controller will now accept the value and move to POINT 2 on the display
15. Exit back to the homepage and check the value on the CHANNEL 1 display window
16. When confirmed, move to the next temperature and repeat the process for point 2 and so on
This process is the same for all three channels.
Figure 12
Important note: Ensure that Point 1 is always used as the lowest temperature and offsets are entered in ascending
order. If the values are place out of order then the controller will disregard them.
There is also the capability to apply a fixed offset that will change the temperature at all temperatures. This is
accessible via the USER ACCESS PAGE. For example, if the temperature requires to be raised by +4° at the top
zone. Scroll to the “top zone fixed offset” and apply the value. The temperature will now be adjusted by increasing
the value by 4°C at ALL temperatures across the range, but in the top zone only. This would particularly useful if the
temperature needs a quick adjustment and the user does not want to calibrate the entire furnace.

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3 Zone Metrological Furnace 465 Iss.13 –11/16
Enabling the AUTOTUNE feature:
The equipment has the ability to AUTOTUNE the control parameters to hone the temperature stability at a specific
block temperature. When enabled it will allow the controller to cycle the temperature of the block and calculate the
best values for this temperature. After two cycles it will install the calculated values and use these for the control
loop. You are not required to log in to access this feature.
To enable the AUTOTUNE feature:
1. Scroll to the USER ACCESS page
2. Press the Scroll button and then select the desired zone AUTOTUNE feature using the down button
3. Press the Scroll button again to highlight the feature
4. Use the up/down button to select ON
5. Press the Scroll button again to enter the value.
6. The controller will now begin the tuning process
During the tuning process, AT can now be seen to the left of the clock on the ISOTECH homepage.
To disable the tuning feature during a tune, repeat the process above and select OFF. This will now disable the tune
and install the previous values.
How to change the Date and Time or the Language of the equipment:
The Date and time of the equipment can be changed to suit local time. This can also incorporate the any daylight
saving time in the time zone of your country or region. The display language of some of the display screens can also
be change to suit the local language.
The options for this are:
English
French
German
Italian
Spanish
Note: Only the Supervisor and Engineer menus will read in the alternative language. The Isotech Home screen will
still read in English when this feature is used.
To change the DATE and TIME or LANGUAGE:
To access these features you will need to log in as the Engineer.
When logged in, scroll to the INSTRUMENT tab on the Engineer homepage
Press the SCROLL button to enter
Scroll to CLOCK and enter by pressing SCROLL button
Alternatively scroll to LOCALE and enter by pressing SCROLL button
Adjust as necessary and exit engineer mode