Isotech 915 Operating instructions

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
PARALLEL TUBE
LIQUID BATH
MODEL 915
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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Parallel Tube Liquid Bath model 915 Iss.07–09/13
CONTENTS
CONTENTS ....................................................................................................................................................................................... 2
GUARANTEE...................................................................................................................................................................................... 3
CAUTIONARY NOTE........................................................................................................................................................................ 4
EMC INFORMATION ........................................................................................................................................................................ 5
ELECTRICAL SAFETY ........................................................................................................................................................................ 5
HEALTH AND SAFETY INSTRUCTIONS ......................................................................................................................................... 6
ON ARRIVAL ...................................................................................................................................................................................... 7
ELECTRICITY SUPPLY....................................................................................................................................................................... 8
IMPORTANT - READ THIS NOW!.................................................................................................................................................... 9
CHILLERS ....................................................................................................................................................................................... 9
SETTING UP................................................................................................................................................................................... 9
FIGURE 1: FRONT PANEL CONTROLS......................................................................................................................................... 10
USING THE CONTROLLER............................................................................................................................................................ 11
FRONT PANEL LAYOUT ............................................................................................................................................................ 11
The Temperature Controller..................................................................................................................................................... 11
Altering the Setpoint .................................................................................................................................................................. 11
ADVANCED CONTROLLER FEATURES.................................................................................................................................... 11
Setpoint Ramp Rate....................................................................................................................................................................11
Instrument Address....................................................................................................................................................................12
Monitoring the Controller Status ...............................................................................................................................................12
Units........................................................................................................................................................................................... 12
DIAGNOSTIC ALARMS.................................................................................................................................................................... 13
CONTROLLER ERROR MESSAGES............................................................................................................................................. 13
OVER TEMPERATURE CONTROLLER........................................................................................................................................... 14
SET / RESET BUTTON................................................................................................................................................................. 14
HEATER ENABLED / DISABLED LIGHT ..................................................................................................................................... 14
FLOW CONTROL ........................................................................................................................................................................... 14
OPERATION AND INITIAL TESTING ............................................................................................................................................ 15
LIQUIDS ........................................................................................................................................................................................... 16
CHOICE OF LIQUIDS.................................................................................................................................................................. 16
LIQUID LEVEL.............................................................................................................................................................................. 16
CHANGING LIQUIDS.................................................................................................................................................................. 16
USING EXTERNAL CHILLERS ........................................................................................................................................................ 18
TROUBLE SHOOTING.................................................................................................................................................................... 19
USING THE PC INTERFACE ........................................................................................................................................................... 20
CONNECTIONS.......................................................................................................................................................................... 20
CAL NOTEPAD................................................................................................................................................................................ 21
DEVELOPMENT .......................................................................................................................................................................... 21
HOW TO INSTALL CAL NOTEPAD .......................................................................................................................................... 22
PROTOCOL ................................................................................................................................................................................. 22
EXPLODED VIEW OF CALIBRATION TUBE COVER (915/05) .................................................................................................... 23
ACCESSORIES .................................................................................................................................................................................. 24

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
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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Parallel Tube Liquid Bath model 915 Iss.07–09/13
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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Parallel Tube Liquid Bath model 915 Iss.07–09/13
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 degrees 2.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
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.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
ON ARRIVAL
Check List:
You should have the following parts;
1. Main Bath Assembly.
2. One overflow and one drain pipe.
3. This User Maintenance Manual/Handbook.
4. Mains Lead.
5. PC Comms Lead.
Optional accessories are available and will on be present if specified on your order, see page 24.
In the unlikely event of any items arriving damaged please retain the packing materials (which may need to be
inspected later) and then contact your supplier.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
ELECTRICITY SUPPLY
Before connecting to the electricity supply please familiarise yourself with the parts of the manual relevant to your
model.
Your unit's supply voltage requirement is specified on a plate on the instrument along with the serial number. All Fast-
Cal units 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)

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
IMPORTANT - READ THIS NOW!
CHILLERS
If supplied these devices should be left to settle for 24 hours before use with the flexible hose in an upright position.
This will allow the internal oil to return to its correct position if it has been disturbed during transit.
SETTING UP
The whole manual should be carefully read before using the bath, and then set the bath up as follows.
Connect the drain pipe to the drain tap and the overflow pipe to the side overflow pipe. Place a suitable container
under the overflow pipe. Ensure the tap is shut, i.e. lever at 90° to the tap body. If the equalising block is to be used it
should be placed in position now.
Fill the bath with suitable liquid, water is probably best for initial testing. Fill the bath until the level is 10mm below the
top of the round central calibration tube
ALWAYS ISOLATE THE BATH FROM THE SUPPLY WHEN CHANGING LIQUIDS
Turn the flow control to the mid position.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
FIGURE 1: FRONT PANEL CONTROLS

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
USING THE CONTROLLER
FRONT PANEL LAYOUT
The Temperature Controller
The controller has a dual display, the upper display indicates the nominal block temperature, and the lower display
indicates the desired temperature or setpoint.
Altering the Setpoint
To change the setpoint of the controller simply use the UP and DOWN keys to raise and lower the setpoint to the
required value. The lower display changes to indicate the new setpoint.
ADVANCED CONTROLLER FEATURES
Setpoint Ramp Rate
By default the bath is configured to heat (and cool) as quickly as possible. There may be some calibration applications
where it is advantageous to limit the heating (or cooling rate).
An example might be when testing bimetallic thermostats, by forcing the bath to heat at a controlled rate it is easier
to determine the temperature at which the thermostat changes state.
The bath can have its heating rate limited with the Setpoint Ramp Rate feature. This feature is accessed from the
Scroll key. Depress the key until the display shows,
SPrr

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
On the Upper Display, the lower display will show the current value from OFF (default) to 999.9. The desired rate is
set here with the UP and DOWN keys, the units are °C/min.
When the SPrr is active the controller display will show "RUN", the lower setpoint display will now automatically
update with the current value, known as the working setpoint. The setpoint can be seen by pressing either the UP
and DOWN key.
The Setpoint ramp rate operates when the bath is heating and cooling.
Instrument Address
The controller has a configurable "address" which is used for PC communications. Each instrument has an address,
this allows several instruments to be connected in parallel on the same communications bus. The default value is 1.
This address would only need to be changed if more than one bath is connected to the same PC port.
To check the Address value press the scroll key until the top display indicates,
Addr
The lower display will show the current value that can be modified with the UP and DOWN keys.
Monitoring the Controller Status
A row of beacons indicate the controllers status as follows,
OP1 Heat Output
REM This beacon indicates activity on the PC interface
Units
Momentary pressing the Scroll key will show the controller units °C or °F.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
DIAGNOSTIC ALARMS
These indicate that a fault exists in either the controller or the sensor.
CONTROLLER ERROR MESSAGES
The instruments include powerful diagnostics and in the unlikely event of an internal failure, or a sensor error, one of
the following error messages may be displayed.
Display
shows
What it means
What to do about it
EE.Er
Electrically Erasable Memory Error:
The value of an operator or configuration parameter has
been corrupted
Contact Isotech
S.br
Sensor Break:
Input sensor is unreliable or the input signal is out of range.
Contact Isotech
HW.Er
Hardware error :
Indication that a module is of the wrong
type, missing or faulty
Contact Isotech
LLLL
Out of Display range, low reading
Contact Isotech
HHHH
Out of Display range, high reading
Contact Isotech
Err1
Error 1: ROM self-test fail
Consult Isotech
Err2
Error 2: RAM self-test fail
Consult Isotech
Err3
Error 3: Watchdog fail
Consult Isotech
Err4
Error 4: Keyboard failure
Stuck button, or a button was pressed during power up.
Switch the power off and then on
without touching any of the controller
buttons.
Err5
Error 5: Input circuit failure
Consult Isotech
Pwr.F
Power failure . The line voltage is too low
Check that the supply to the controller
is within the rated limits

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
OVER TEMPERATURE CONTROLLER
This device is an important safety feature. It has its own temperature sensor and will isolate the heater if the
temperature exceeds the set temperature. It should be set slightly higher, perhaps 10 –20°C higher than the working
temperature or to the maximum safe temperature of the fluid in use. Which ever is the lowest value. IT MUST BE
SET IN THIS WAY TO ENSURE SAFE USE OF THE BATH. Suitably set it will allow for protection against
component failure and also operator error when setting the controller, either from the front panel or remotely from
a computer.
The over temperature controller is used in conjunction with the Set / Reset Button.
SET / RESET BUTTON
When the bath is first switched on the heater is disabled. When this button is pressed the heater will become enabled
and the light next to the button will become illuminated. If the bath temperature exceeds the value set in the over
temperature controller the heater will no longer be enabled and the light will turn off.
HEATER ENABLED / DISABLED LIGHT
As mentioned above the light will be lit when the heater is enabled and will be off when the heater is disabled.
FLOW CONTROL
This controls the flow rate of the liquid. It allows for a wide range of liquid viscosities and provides easy adjustment. It
should initially be set to the mid position and then adjusted whilst the flow is observed.
The optimum position for a particular liquid at a specific temperature may need to be determined experimentally. As
a general guide the flow should be increased until it becomes turbulent and then backed off slightly. Generally the
stability will be optimum when the flow is high but stable.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
OPERATION AND INITIAL TESTING
Set the bath up as described in the earlier "Setting Up Section". For convenience it is suggested that a newly received
bath should be tested at 50°C with water as the operating liquid.
Connect the bath to the supply and switch on.
DO NOT PRESS THE SET BUTTON YET!
1. Set the over temperature controller to a suitable value, see earlier.
2. Set the set point of the temperature controller to the desired value.
3. Adjust the flow if necessary.
4. Press the Set / Reset Button. The bath should now reach and control at the target set point.
The bath may now be used for calibration, see tutorial.
For temperatures above 40°C ensure any chiller probe is not in the liquid and that the chiller is turned off.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
LIQUIDS
CHOICE OF LIQUIDS
The choice of liquid is important. If it is too viscous at the operating temperature then the bath may not perform
correctly. Other criteria also need to be met, such as safety, operating range and fume emission for example. Isotech
is able to supply a number of fluids for various temperature ranges, see catalogue.
Unfortunately, there is not one fluid which can be used over the whole operating range of the bath. Beware of oils
that are claimed to work from below ambient to over 100°C. Whilst we do not supply or recommend such liquids.
others do. It is our experience that such oils absorb moisture from the air when used below the dew point. Then at
temperatures around 100°C this moisture boils and can lead to the oil spilling from the top of the bath. Even without
the boiling risk the oil is soon spoilt by the ingressions of moisture and the oil has to be replaced regularly, which can
be an expensive task. It will be seen that when changing fluids from say water to oil that it is important that ALL the
water has been removed before adding the oil.
As oils approach their upper operating limit fumes become significant and fume extraction becomes essential. It is for
this reason that the upper limit of the bath is 300°C. Isothermal Technology manufactures a fluidised alumina bath, the
Ayries Bath which overcomes the limitations of oils and may be used to 700°C without fuming problems.
Below ambient we use a mixture of methanol and water. Methanol is poisonous and has a low flash point. It needs to
be used very carefully by those suitably trained and aware of the dangers if handled inappropriately. As local safety
requirements vary not only from country to country but also from organisation to organisation the safety aspects of
these fluids should be determined with the users safety officer.
LIQUID LEVEL
All liquids expand as they are heated and contract when they cool.
The bath has been designed to allow for varying liquid volumes and also features an overflow system which prevents
the liquid from spilling from the top of the bath.
The optimum liquid level with the motor off at the operating temperature is for the liquid to be level with the top of
the calibration tube.
When working below ambient it can be useful to pre chill and store in a thermos flask a quantity of the operating fluid.
This prevents large thermal shocks when the bath is "topped" up and helps reduce cooling time.
CHANGING LIQUIDS
If possible it is best to plan so that liquids do not need to be frequently changed. This may be achieved by liquid
choice, determining convenient calibration points or having more than one bath - each with a different liquid to cover
the routine calibration range.
To change the liquid,
1. Disconnect from the supply.
2. Ensure the liquid is at a safe handling temperature. Neither too hot nor too cool then open the drain tap.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
3. Drain the liquid into a clean container of adequate capacity, properly labelled for future use.
4. Clean the bath. Detergent and absorbent paper will assist. If the bath has been used with oil it can be helpful
to re fill with water and detergent and to allow the mixture to circulate before draining again.
5. Close the tap.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
USING EXTERNAL CHILLERS
Refer to the Chiller operating instructions before using the chiller.
The cooling probe should be fully immersed into the chiller probe tube. Push the hose firmly into position until the
end of the chiller probe locates at the bottom of the tube.
This chiller has a maximum operating temperature of 40°C.
Remove the chiller probe from the bath when operating above 40°C temperature.
The chiller probe should not be allowed to reach temperatures higher than 40°C.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
TROUBLE SHOOTING
Problem
Solution
No Power
Check Fuse
Motor does not turn
Check Fuse and flow control setting
Drive belt slipping or broken
To replace the drive belt with the spare belt supplied, remove the four
screws securing the motor cover. Loosen the motor bolts and remove the
worn belt. Replace with the new one and readjust the motor via the four
bolts. Replace the motor cover.
Temperature does not rise
Check over temperature controller setting and press Set button
Liquids flows unevenly
Check Flow Setting. If no improvement the liquid may not be suitable for
us at this temperature
Bath Overflows
Check Overflow is not blocked and liquid level. Remember oil expands as
it heats!
N.B. If the oil suddenly expands and overflows at 100°C it may have been contaminated with water and the oil
should be replaced after this has been cleaned.

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Parallel Tube Liquid Bath model 915 Iss.07–09/13
USING THE PC INTERFACE
The bath includes an RS422 PC interface and a special converter cable that allows use with the a standard RS232 port.
When using the bath with an RS232 port it is essential that this converter cable is used. Replacement cables are
available from Isotech, part number ISO-232-432. A further lead is available as an option, Part Number ISO-422-422
lead which permits up to 5 instruments to be daisy chained together.
The benefit of this approach is that a number of calibration baths may be connected together in a "daisy chain"
configuration - and then linked to a single RS232, see diagram.
Note: The RS 422 standard specifies a maximum lead length of 1200M (4000ft). A true RS422 port will be required to
realise such lead lengths. The Isotech conversion leads are suitable for maximum combined lead lengths of 10M that is
adequate for most applications.
CONNECTIONS
For RS232 use simply connect the Isotech cable, a 9 to 25 pin converter is included to suit PCs with a 25 pin serial
converter.
RS422 Connections
Pin Connection
4 Tx+ A
5 Tx-B
8 Rx+ A
9 Rx-B
1 Common