Isotech OCEANUS-6 Series Operating instructions

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Oceanus-6 Series Model 580 Iss.08 –04/15
OCEANUS-6 SERIES
MODEL 580
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.

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Oceanus-6 Series Model 580 Iss.08 –04/15
CONTENTS
GUARANTEE.................................................................................................................................................................................... 4
EMC INFORMATION.............................................................................................................................................................. 5
ELECTRICAL SAFETY ............................................................................................................................................................. 5
ENVIRONMENTAL RATINGS ..................................................................................................................................................... 5
HEALTH AND SAFETY INSTRUCTIONS ....................................................................................................................................... 6
CAUTIONARY NOTE...................................................................................................................................................................... 7
UNPACKING AND INITIAL INSPECTION .................................................................................................................................... 8
ELECTRICITY SUPPLY................................................................................................................................................................. 8
OCEANUS-6 MODEL 580 ‘DO’S AND DON’TS’ .......................................................................................................................... 9
INTRODUCTION .......................................................................................................................................................................... 10
COMPARISON CALIBRATION ................................................................................................................................................. 10
Using the Controller .............................................................................................................................................10
Using the Indicator (Not Basic (B) Model)............................................................................................................ 11
Using External Standards ...................................................................................................................................... 11
MODE OF OPERATION................................................................................................................................................................ 12
ITS-90 FIXED POINT CALIBRATION ....................................................................................................................................... 12
METAL BLOCK BATH ............................................................................................................................................................... 12
STIRRED LIQUID BATH ............................................................................................................................................................ 12
STIRRED ICE BATH ................................................................................................................................................................... 13
BLACK BODY SOURCE............................................................................................................................................................. 13
SURFACE SENSOR CALIBRATION........................................................................................................................................... 13
ADJUSTING THE TIMER ............................................................................................................................................................... 14
USING WATER & GALLIUM FIXED POINT CELLS ..................................................................................................................... 14
WATER TRIPLE POINT CELL.................................................................................................................................................... 15
LARGE GALLIUM CELL ............................................................................................................................................................. 15
SLIM GALLIUM CELL ................................................................................................................................................................. 16
THERMOMETRIC FIXED POINTS (a tutorial note)...................................................................................................................... 17
HINT ON HOW TO MEASURE THE TRUE TEMPERATURE INSIDE THE ACCESSORIES SUPPLIED WITH THE OCEANUS-6
SERIES ............................................................................................................................................................................................. 18
The Controller ...................................................................................................................................................... 18
The Reference Thermometer............................................................................................................................... 18
The Industrial Thermometer ................................................................................................................................18
SPECIFICATION ............................................................................................................................................................................ 19
OCEANUS-6 PERFORMANCE GRAPH ........................................................................................................................................ 20
OPERATING THE OCEANUS-6 ................................................................................................................................................... 21
FRONT PANEL LAYOUT .......................................................................................................................................................... 21
The Temperature Controller................................................................................................................................ 21
Altering the Setpoint ............................................................................................................................................. 21
ADVANCED CONTROLLER FEATURES.................................................................................................................................. 21
Setpoint Ramp Rate............................................................................................................................................... 21
Instrument Address............................................................................................................................................... 22
MONITORING THE CONTROLLER STATUS ......................................................................................................................... 22
UNITS ......................................................................................................................................................................................... 22
THE TEMPERATURE INDICATOR (NOT BASIC (B) MODELS) ............................................................................................. 22
SETTING THE INPUT TYPE ..................................................................................................................................................... 22
ENABLING / DISABLING CUSTOM CALIBRATION................................................................................................................ 23
INSTRUMENT ADDRESS........................................................................................................................................................... 23
MONITORING THE INDICATOR STATUS.............................................................................................................................. 24
UNITS ......................................................................................................................................................................................... 24
ADVANCED INDICATOR OPERATION .................................................................................................................................. 24
CALIBRATION DATA EXAMPLE .................................................................................................................................................. 25
CONNECTING A CURRENT TRANSMITTER (UP TO 20MA) ................................................................................................... 25
SELECTING CONFIGURATION LEVEL ................................................................................................................................... 26
TESTING THERMOSTATS ........................................................................................................................................................ 27
USING THE PC INTERFACE ......................................................................................................................................................... 28

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Oceanus-6 Series Model 580 Iss.08 –04/15
CONNECTIONS........................................................................................................................................................................ 28
CAL NOTEPAD.............................................................................................................................................................................. 29
DEVELOPMENT ........................................................................................................................................................................ 29
HOW TO INSTALL CAL NOTEPAD ........................................................................................................................................ 30
PROTOCOL ............................................................................................................................................................................... 30
DIAGNOSTIC ALARMS.................................................................................................................................................................. 31
CONTROLLER ERROR MESSAGES........................................................................................................................................... 31
INITIAL TESTING........................................................................................................................................................................... 32
IMPORTANT NOTICE .............................................................................................................................................................. 32
MAINTENANCE ............................................................................................................................................................................ 33
FIGURE 1 ........................................................................................................................................................................................ 34
APPENDIX 1: OCEANUS-6 SERIES TROUBLE SHOOTING....................................................................................................... 35
Unit fails to operate............................................................................................................................................... 35
Will not cool properly ........................................................................................................................................... 35
Indicator reads incorrectly ....................................................................................................................................35
Unit unstable .........................................................................................................................................................35
Cannot establish PC Communications.................................................................................................................. 35
APPENDIX 2: INDICATOR CONFIGURATION (Reference Only).............................................................................................. 36
Config.INST........................................................................................................................................................... 36
Config.IP................................................................................................................................................................ 36
Config.CAL............................................................................................................................................................ 36
Config.AL ..............................................................................................................................................................37
Config.HA.............................................................................................................................................................. 37
Config.1A ..............................................................................................................................................................37
Config.2A ..............................................................................................................................................................37
APPENDIX 3: ACCESSORIES PARTS LIST .................................................................................................................................... 38
OPTION 1 .................................................................................................................................................................................. 38
OPTION 2 & 3............................................................................................................................................................................ 38
OPTION 4 .................................................................................................................................................................................. 38
OPTION 5 .................................................................................................................................................................................. 38
OPTION 6 .................................................................................................................................................................................. 38
LIQUID IN GLASS THERMOMETER SUPPORT KIT - 580-06-00......................................................................39
LIQUID CONTAINER KIT - 580-06-07............................................................................................................... 39

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Oceanus-6 Series Model 580 Iss.08 –04/15
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.
We recommend that this instrument to be re-calibrated annually.
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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Oceanus-6 Series Model 580 Iss.08 –04/15
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.
The apparatus has two input connectors for temperature sensors, see Figure 1. These inputs are only suitable for
either a thermocouple or resistance thermometer. No other sensor or signal may be connected.
ENVIRONMENTAL RATINGS
Operating Temperature 0-50°C
Relative Humidity 5-95%, non condensing

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Oceanus-6 Series Model 580 Iss.08 –04/15
HEALTH AND SAFETY INSTRUCTIONS
1. Read this entire handbook 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 has 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.

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Oceanus-6 Series Model 580 Iss.08 –04/15
CAUTIONARY NOTE
ISOTECH PRODUCTS ARE INTENDED FOR USE BY TECHNICALLY TRAINED AND COMPETENT
PERSONNEL FAMILIAR WITH GOOD MEASUREMENT PRACTICES.
IT IS EXPECTED THAT PERSONNEL USING THIS EQUIPMENT WILL BE COMPETENT WITH THE
MANAGEMENT OF APPARATUS WHICH MAY BE POWERED OR UNDER EXTREMES OF TEMPERATURE, AND
ARE ABLE TO APPRECIATE THE HAZARDS WHICH MAY BE ASSOCIATED WITH, AND THE PRECAUTIONS
TO BE TAKEN WITH, SUCH EQUIPMENT.

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Oceanus-6 Series Model 580 Iss.08 –04/15
UNPACKING AND INITIAL INSPECTION
Our Packing Department uses custom designed packaging to send out your unit, but as accidents can still happen in
transit, you are advised, after unpacking the unit, to inspect it for any sign of shipping damage, and confirm that your
delivery is in accordance with the packing note. Should you find any damage or that part of the delivery is missing
notify us or our agent, and the carrier immediately. If the unit is damaged you should keep the packing for possible
insurance assessment.
ELECTRICITY SUPPLY
Before connecting to the electricity supply please familiarise yourself with the parts of the handbook relevant to your
model.
Your unit's supply voltage requirement is specified on a plate on the instrument along with the serial number. All
Oceanus-6 instruments will work on an electricity supply frequency of 50Hz or 60Hz.
The apparatus is provided with an approved power cord. If the plug is not suitable for your location then the plug
should be removed and replaced with an appropriate plug.
Take care to ensure the old plug is disposed safely.
The cable is colour coded as follows:
COLOUR FUNCTION
Green/yellow Earth (Ground)
Brown Live (line)
Blue Neutral
Please ensure that your unit is correctly connected to the electricity supply.
THE APPARATUS MUST BE CORRECTLY EARTHED (GROUNDED)
The units on/off switch is located on the power inlet. Take care NOT to switch the unit off when it is hot - allow to
cool first.

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Oceanus-6 Series Model 580 Iss.08 –04/15
OCEANUS-6 MODEL 580 ‘DO’S AND DON’TS’
DO NOT handle the accessories when they are very hot or very cold.
DO NOT place hot or cold accessories back in the carrying case
DO NOT use the pocket designed for the black body source sensor to measure the temperature of the insert, stirred
liquid bath or surface calibrator.
DO use that pocket for pre-warming, pre-cooling or storage.
DO NOT spill liquids inside the Oceanus-6
DO NOT use liquids outside their recommended temperature range
DO NOT use viscous liquids in the stirred liquid accessory, the stirring will be restricted and larger gradients will
occur.
DO NOT mix liquids. If you are using 1 container for different liquids make sure the container is completely clean
and dry before adding another liquid.
DO NOT worry if the black anodising gets discoloured or scratched. We can supply some special black touch up
paint.
DO NOT rely on the controller to tell you the temperature of the insert or stirred liquid bath. It’s job is only to
provide an isothermal volume. It is the calibrated working standard that is used to measure actual temperature.
DO NOT calibrate very large sensors in the Oceanus-6 unless you can accept large immersion errors. We have
larger products for larger sensors.
DO NOT try to straighten the working standard, it is deliberately bent so that it does not interfere with the sensors
you are calibrating.

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Oceanus-6 Series Model 580 Iss.08 –04/15
INTRODUCTION
The Oceanus-6 range of products allows unprecedented flexibility for the calibration of temperature sensors. The
Oceanus-6 range may be used with the following options:
1. An ITS-90 Fixed Point Apparatus
1. As a Metal Block Bath
2. As a Stirred Liquid Bath
3. As a Stirred Ice Bath
4. A Black Body Source
5. A Surface Sensor Calibrator
The Oceanus-6 is available in two variants. The Basic (B) model which incorporates a single temperature controller.
The Potts as Site (S) model also include a temperature indicator and a timer.
COMPARISON CALIBRATION
By definition, one compares industrial thermometers to a calibrated standard.
There are 3 methods commonly used.
Using the Controller
Using the controller as the “calibrated standard” this method means that the complete bath is calibrated by
comparing the controller reading to a calibrated standard placed in the bath.
This is a common method but is unsafe since the control sensor is
a) inaccessible
b) in the wrong place to give correct temperature of the insert
For these reasons it fails to satisfy ISO9000 and gives large uncertainties.

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Oceanus-6 Series Model 580 Iss.08 –04/15
Using the Indicator (Not Basic (B) Model)
In these an indicator and external calibrated sensor are used to measure the temperature of the insert. This
arrangement gives good accurate and reliable results. To recalibrate however it does mean sending the whole
calibrator back to the calibration laboratory. This, the calibrator is self-contained, self-sufficient and meets ISO9000
requirements.
Using External Standards
Here a separate indicator and calibrated sensor are used to measure the inserts temperature. This can give the most
accurate and reliable results, depending on the indicator.
It means that the calibrator does not need calibrating only the indicator and its calibrated sensor need re-calibration,
but this option is more bulky, expensive and less portable than above. It also meets ISO9000 requirements.

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Oceanus-6 Series Model 580 Iss.08 –04/15
MODE OF OPERATION
ITS-90 FIXED POINT CALIBRATION
The ITS-90 fixed point function of the Oceanus-6 is well suited for fast, convenient, mess free calibration of
thermometers to uncertainties as low at 0.001°C.
The special cell is placed into the Oceanus-6 calibration well. The stir speed control should be set to the OFF
position.
The equipment incorporates a timer which can change temperatures to allow MELTING or FREEZING of a Gallium
Cell. Once initiated the Cell can be arranged to be on the melt plateau during the day and automatically frozen and
bought back to the melt plateau overnight.
For use with a Gallium Cell the well temperature should be 30.5°C for the MELT or 15°C for the FREEZE.
On power up the timer is set to run at setpoint 1 for 20 hours at setpoint 2 for 4 hours.
METAL BLOCK BATH
The metal block bath function of the Oceanus-6 is well suited for fast, convenient, mess free calibration of
temperature sensors.
The Oceanus-6 metal insert is placed into the calibration well. The stir speed control should be set to the OFF
position (turn fully anti-clockwise).
The thermometers under test are placed into suitable holes in metal insert (part number 580-06-03), see accessory
section page 38. A calibrated reference probe should be placed into the insert and the actual temperature can be
read from the temperature indicator.
For traceable calibration the actual value of the insert temperature should be recorded along with the values from the
sensors under test.
STIRRED LIQUID BATH
The stirred liquid bath function of the Oceanus-6 is well suited for odd shaped sensors which will not easily be
accommodated in a metal insert.
The Oceanus-6 Liquid Container (part number 580-06-07) is placed into the calibration well and the container is filled
with a suitable liquid, see accessory section page 38 for the temperature range that the bath is to be used over. The
container should be filled to 25mm from the top of the tank. Care must be taken to adjust the level as the liquid
contracts or expands with temperature changes. The stirrer speed control is set ON and to the mid position. If
necessary the speed to can be adjusted to give the optimum value for a particular application, this position should be
found experimentally and then noted for future use.

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Oceanus-6 Series Model 580 Iss.08 –04/15
The thermometers under test are placed into the liquid. Two accessories are available to support the thermometers.
a) The Thermometer Support Kit (part number 580-06-00) allows thermometers with a diameter of 2 to
6.5mm to be suspended in the liquid.
b) The Sensor Guide which fits into the tank and can support a number of thermometers (part number 580-02-
16).
It is important that one of the accessories is used to prevent the probes from reaching the bottom of the tank which
would stop the stirring action. A calibrated reference probe should be placed into the liquid and the actual
temperature can be read from the temperature indicator.
For traceable calibration the actual value of the liquid temperature should be recorded along with the values from the
sensors under test.
STIRRED ICE BATH
The Stirred Ice Bath function is as the Stirred Liquid Bath. The liquid container - part number 580-06-07 is filled with
water, the stirrer speed control set to mid-position and the controller set to 0.0°C. Once the controller has stabilized
at 0.0°C allow 10-15 minutes before starting calibration.
BLACK BODY SOURCE
The black body function of the Oceanus-6 is well suited for fast, convenient, mess free calibration of infra-red
temperature sensors.
The Oceanus-6 black body target (part number 580-02-12); see accessory section page 38 is placed into the
calibration well. The stir speed control should be set to the OFF position.
The units under test should be aligned with the target.
A calibrated reference probe should be placed into the hole in the block and the actual temperature can be read from
the temperature indicator to which the infrared thermometer(s) are compared.
SURFACE SENSOR CALIBRATION
The surface sensor function of the Oceanus-6 is well suited for fast, convenient, mess free calibration of most surface
temperature sensors.
The Oceanus-6 surface sensor insert (part number 580-02-11), see accessory section page 38, is placed into the
calibration well. The stir speed control should be set to the OFF position.
A calibrated probe (part number 935-14-84) is placed in the pocket of the surface sensor insert and connected to the
temperature indicator. Surface sensors are placed on top of the insert and when stable compared to the calibrated
probe.

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Oceanus-6 Series Model 580 Iss.08 –04/15
ADJUSTING THE TIMER

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Oceanus-6 Series Model 580 Iss.08 –04/15
USING WATER & GALLIUM FIXED POINT CELLS
WATER TRIPLE POINT CELL
The adapter rings should be fitted above and below the cell so that the cell sits centrally in the block. The top of the
well should then be thermally insulated with foam expanded polystyrene, tissue paper etc.
Switch on the Oceanus and set the temperature to -7°C. The Oceanus-6 will cool much quicker than the cell because
there is an air gap between the cell and the block; therefore monitor the temperature of the cell using a
thermocouple or resistance thermometer inside the cells re-entrant tube.
When the cell has reached about -6°C gently remove the cell from the Oceanus-6 and supporting the base of the cell
in one hand, gently flick the top of the cell to one side, where upon ice forms and the temperature rises to the triple
point value. In order to stabilise the ice mush which tends to rise to the surface, the cell is returned to the bath at -
7°C. It is left there for ten minutes to stabilise. The cell is then briefly removed from the block. A small amount of
ambient temperature alcohol introduced into the reentrant tube of the cell (washing the reentrant tube walls as it is
introduced) will free the ice mantle from the reentrant tube. The outer surface of ice is then warmed by hand until
the sheath of ice is free to rotate. A gentle axial twist of the cell will confirm the mantle is free. The cell is returned
quickly to the Oceanus-6 block and the temperature increased to about -1°C. This gradually causes the ice to grow
back to the outer wall of the cell and compensates for coolth losses from the thermometers being calibrated.
The cell should be periodically inspected and if necessary, the ice sheath freed from the wall of the cell.
There is nothing sacrosanct about the above procedure and provided between ⅓and ⅔of the cell is ice then the
triple point calibration is valid.
The best temperature to maintain the cell can be found only after use.
It will depend on:
1. The number of sensors being calibrated.
2. The ambient temperature.
If, at any time, an ice bridge forms on the surface of the water in the cell, the cell may rupture. The likelihood of this
happening is small since the surface of the cell is above the block of the Oceanus-6, however the cell should be
checked regularly.
The accuracy with which the cell may be used to check a thermometers calibration may, in practice, be limited by the
extent of its immersion in the cell, or by the self-heating of the thermometer. The magnitude of these effects may be
checked (i) by reducing the immersion depth and (ii) by making measurements at two currents through the
thermometer.
LARGE GALLIUM CELL
The adapter rings should be fitted above and below the cell so that the cell sits centrally in the block. The top of the
well should then be thermally insulated with foam expanded polystyrene, tissue paper etc.
Set the Oceanus-6 to give a well temperature of approximately 32°C. Monitor the Cell until the Gallium starts to
melt, at this stage the well temperature can be lowered to 30.5°C which will give a long melt plateau.

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Oceanus-6 Series Model 580 Iss.08 –04/15
This two step procedure will lead to a rapid melt and long plateau. At the end of the plateau the set point should be
set to 15°C to freeze the Cell. It is essential the Cell freezes from the bottom upwards. Leaving the Cell in the
Oceanus-6 until it is frozen will ensure this happens and eliminates the possibility of the cell being damaged by the
expansion of the Gallium during the freeze.
NB. For the flattest melt plateau, remove the cell from the Oceanus-6 and freeze by standing the bottom third of the
cell in crushed ice or an ice/water mixture. Once frozen it can be melted as before but first make sure the cell is
thoroughly dry before re-introducing into the Oceanus-6.
The operation can be automated - see page 21.
The accuracy with which the cell may be used to check a thermometers calibration may, in practice, be limited by the
extent of its immersion in the cell, or by the self-heating of the thermometer. The magnitude of these effects may be
checked (i) by reducing the immersion depth and (ii) by making measurements at two currents through the
thermometer.
SLIM GALLIUM CELL
Please see separate handbook for this cell.

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Oceanus-6 Series Model 580 Iss.08 –04/15
THERMOMETRIC FIXED POINTS (a tutorial note)
Temperature scales used in science and industry are defined by a series of "fixed points", which are realised by
establishing thermal conditions under which pure materials exhibit equilibrium between two or three phases. A scale
assigns numerical values to the temperatures at which these phase equilibria exist. For example, the temperature at
which pure water exists simultaneously in its liquid, solid and gas phases (triple point) has been assigned the numerical
value of 0.01°C on the International Temperature Scale, and the value of 273.16K on the Kelvin Thermodynamic
Temperature Scale. Examples of other defining fixed points of the International Temperature Scale of 1990 are the
respective liquid-solid equilibria of tin, zinc and silver under 1 standard atmosphere pressure.
In some important disciplines it is desirable to realise a thermometric fixed point between 0 and 100°C, frequently in
the vicinity of body or environmental-temperature. The melting temperature of high purity gallium, 29.7646°C, is a
fixed point that can be useful in this context.
The solid-liquid equilibrium point of gallium is realised in cells such as those shown in figure 1 or reference 2. A
quantity of pure gallium is contained in a vessel which provides, also, a re-entrant well for insertion of a thermometer.
The cycle for realising the melt equilibrium is as follows:
The gallium starts in a single phase, assumed for present purposes to be liquid. The cell is placed in a cold
environment until the gallium has solidified. The phase-change of the metal can be determined by tracing the
temperature of the well. As the metal cools from the liquid phase, the temperature will begin to fall. An initial
smooth drop in temperature will be observed, and then at some temperature below the freezing temperature there
will be seen a reversal and a subsequent rise in temperature. This "undercool" phenomenon is characteristic of many
pure materials, most of which can remain liquid at temperatures below their normal freezing points (if the metal were
initially solid, the temperature would fall uninterruptedly to that of the cold environment).
The reversal takes place as the first crystalline solid forms in the liquid; the temperature rises to the liquid-solid
equilibrium plateau temperature as the metal gives up latent heat on freezing, remaining thereafter at this
temperature until the metal is completely solid. Beyond this stage there will be a smooth drop in temperature to that
of surrounding environment.
To establish the melting condition, the cell is then transferred to an environment maintained at a temperature slightly
above the melt temperature of gallium. This environment may be a stirred fluid bath of sufficient heat capacity and
control capability, or may be the Oceanus-6 POTTS or Gallium Temperature Standard Apparatus Model 17402B
which is designed automatically to raise the temperature of the cell to initiate melting of the metal and then to
maintain it at a correct level. The temperature to which the cell is exposed to melt the metal does not determine the
solid-liquid equilibrium temperature, but it can have a substantial effect on the duration of the (constant-temperature)
melt plateau.
The monitoring thermometer will indicate a rise in temperature in the well as the solid gallium approaches the melt
temperature. Then, beyond the instant at which liquid first begins to form, the temperature will remain constant until
all the metal has melted. The end of the melt plateau is signalled by a rise in well temperature to the temperature of
the surrounding environment. An ITL 17401 gallium cell used in the Model 17402B system can give a plateau duration
of at least 12 hours.
The melting cycle is now complete. The material in the cell is entirely in the liquid phase. Another cycle may be
started immediately, if desired.
17cc of water should be poured into the re-entrant tube to allow proper conduction between cell and thermometer.
For the highest accuracy measurements (to less than 0.1mK of the ITS-90 value) an hour should elapse between
switching to melt and commencing measurements. Alternatively, once the melt has begun the water in the well can
be replaced by warm water at say 40°C to initiate a melt round the re-entrant tube. See CCT96/8 for additional
guidance.

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Oceanus-6 Series Model 580 Iss.08 –04/15
HINT ON HOW TO MEASURE THE TRUE TEMPERATURE INSIDE THE
ACCESSORIES SUPPLIED WITH THE OCEANUS-6 SERIES
The controller of the Oceanus-6 controls and reads the temperature of the block surrounding the 50mm∅by 300mm
deep calibration well.
There are various accessories including the surface calibration insert, the oil container, black body etc. These adapt
the Oceanus-6 to perform varied calibration functions.
None of these accessories actually get to the block temperature and hence the controller’s temperature because each
accessory has a different immersion characteristic. For this reason the Oceanus-6 like all comparison baths requires a
reference thermometer to indicate the true temperature inside the accessory.
Remember the following:-
The Controller
The controller is used to set a constant temperature and create an isothermal environment for the comparison
calibration of temperature sensors.
The Reference Thermometer
The Reference Thermometer is placed in the accessory or insert and measures the true temperature inside the insert
or accessory.
The Industrial Thermometer
The Industrial thermometer is placed in the accessory or insert and is compared to the True Temperature as
indicated by the reference thermometer. An insert will typically have a 1% immersion error. For more details see -
Depths of Immersion. Tavener J. P. Volume 9.2. Isotech Journal of Thermometry pages 79-87.

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Oceanus-6 Series Model 580 Iss.08 –04/15
SPECIFICATION
Voltage
230VAC (or 115VAC) see ratings plate
Power
300W
Supply Frequency
50/60Hz
Maximum Operating Temperature
110°C
Minimum Operating Temperature
45°C (below ambient)
Stability (Absolute over 30 Minutes)
Metal Block Bath
±0.03°C
Stirred Liquid
±0.025°C
Black Body Source
±0.3°C
Surface Sensor Calibrator
±0.5°C
ITS-90 Fixed Point Apparatus
±0.0002°C
Ice/Water Bath
±0.001°C
Calibration Volume
50mm dia by 300mm deep
Standard Insert Hole Dimensions
6 x 8mm
Insert Options
Adjustable Height Equalising Block
Special drilling available to customer requirements.
Blank
Dimensions (not including handle)
Height 430mm
Width 310mm
Depth 300mm
Weight
17Kg

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Oceanus-6 Series Model 580 Iss.08 –04/15
OCEANUS-6 PERFORMANCE GRAPH