Isotech 915 Operating Manual

NEPTUNE MODEL 915

PARALLEL TUBE

LIQUID BATH

PARALLEL TUBE LIQUID BATH

MODEL 915 HANDBOOK

ISSUE 04 01/05

Isotech North America
154 Brentwood Drive, Unit 3

Colchester, VT 05446

Phone: [phone]
Fax: [phone]

www.isotechna.com

[e-mail]

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

CONTENTS

PAGE NO:

Guarantee 3

CE Information 4 - 5

Health & Safety Information 6

On Arrival 7

Electricity Supply 8

Important Note 9

Figure 1 10

MODEL 915 HANDBOOK

ISSUE 04 01/05

Using the Controller 11 -15

Choice of Liquids 16

Changing Liquids 17

Chillers 18

Trouble Shooting 19

Using the PC Interface 20

Using Cal Notepad 21 - 22

Exploded view of Calibration Tube Cover (915/05) 23

Accessories 24

APPENDIX 1

Using the Isotech High Stability Temperature Controller 25 -26

Stirred Liquid Bath Tutorial A - H

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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.

Serial No:.....................................

Date:.............................................

Isotech North America
154 Brentwood Drive, Unit 3

Colchester, VT 05446

Phone: [phone]
Fax: [phone]

www.isotechna.com

[e-mail]

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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 Handbook)

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 can not 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).

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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, eg. Carbon dust, must be excluded from the apparatus. EN61010
pollution degree 2.

ENVIRONMENTAL RATINGS

Operating Temperature 5-50/C

Relative Humidity 5-95%, non condensing

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HEALTH AND SAFETY

INSTRUCTIONS

1. Wear appropriate protective clothing.

2. Operators of this equipment should be adequately trained in the handling of hot and
cold items and liquids.

3. Do not use the apparatus for jobs other than those for which it was designed, ie. the
calibration of thermometers.

4. Do not handle the apparatus when it is hot (or cold), unless wearing the appropriate
protective clothing and having the necessary training.

5. Do not drill, modify or otherwise change the shape of the apparatus.

6. Do not dismantle the apparatus without disconnecting it from the supply and leaving
time for it to reach ambient temperatures.

7. Do not use the apparatus outside its recommended temperature range.

8. The apparatus is protected by an over temperature circuit, ensure correct settings at all
times.

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ON ARRIVAL

Check List.

You should have the following parts,

1. Main Bath Assembly

2. One overflow and one drain pipe

3. This handbook

4. Mains Lead

Optional accessories are available and will only 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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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.

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 that the old plug is disposed of 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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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, 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 a 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.

FRONT PANEL CONTROLS (See figure 1.)

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FIGURE 1

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ISSUE 04 01/05

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A. USING THE CONTROLLER

FRONT PANEL LAYOUT

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ISSUE 04 01/05

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.

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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

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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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

EE.Er Electrically Erasable Memory Error:

S.br Sensor Break:

HW.Er Hardware error :

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

What it means What to do about it

Contact Isotech
The value of an operator or configuration
parameter has been corrupted

Contact Isotech
Input sensor is unreliable or the input
signal is out of range.

Contact Isotech
Indication that a module is of the wrong
type, missing or faulty

Switch the power off and then on
Stuck button, or a button was pressed
during power up.

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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B. 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.

C. 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.

D. 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.

E. 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.

F. ON / OFF SWITCH

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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 (50.0°C).

3. Adjust the flow if necessary.

4. Only if a chiller has been supplied.

For temperatures above ambient ensure any chiller (cooler) probe is not in the liquid and
that the chiller is turned off.

5. 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.

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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 meet, 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.

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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.

3. Drain the liquid into a clean containers 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 an 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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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.

Remove the chiller probe from the bath when operating above ambient temperature.

The chiller probe should not be allowed to reach temperatures higher than 30/C.

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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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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

Using the Interface

The models are supplied with Cal NotePad as standard. This easy to use package is compatible
with MS Windows 9x. A handbook for Cal NotePad can be found on the first installation disk
in Adobe PDF format. If required a free Adobe PDF reader can be downloaded from,
www.adobe.com.

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CAL NOTEPAD

Cal Notepad can be used to log and display values from the bath and an optional temperature
indicator.

Minimum System Requirements

CNP requires Windows 95 / 98, a minimum of 5Mb of free hard drive space and free serial ports
for the instruments to be connected.

Development

CNP was developed by Isothermal Technology using LabVIEW from National Instruments.

License

Use of the Cal NotePad software program "CNP" is as granted in this license agreement. In using the
CNP
software the user "licensee" is agreeing to the terms of the license. You must read and understand the
terms of this license before using CNP.
1, This license permits licensee to use CNP software on a single computer. The user may make copies
for back up and archival purposes freely as long as the software is only ever in use on a single computer
at any one time. Please enquire about multi-user licenses.
2, CNP is protected by international copyright laws and treaties. CNP must not be distributed to third
parties.
3, CNP must not be reversed engineered, disassembled or de-compiled. Licensee may transfer the
software to a third party provided that no copies or upgrades of CNP are retained.
4, It is the responsibility of the user to ensure the validity of all stored results and printed certificates.
Isothermal Technology Ltd accept no responsibility for any errors caused by inappropriate use, incorrect
set up or any other cause; including defects in the software.
5, Limited Warranty. Isothermal Technology warrants that CNP will perform substantially as described in
this manual for a period of 90 days from receipt. Any distribution media will under normal used be
guaranteed for a period of 90 days.

NO OTHER WARRANTIES, EXCEPT AS STATED ABOVE. The software and documentation is provided
"as is" without warranty of any kind and no other warranties (either expressed or implied) are made with
regard to CNP. Isothermal Technology does not warrant, guarantee or make any representations
regarding the use or results of the use of the software or documentation and does not warrant that the
operation of CNP will be error free.

In no event will Isothermal Technology, its employees, agents or other associated people be liable for
direct, indirect, incidental or consequential damages, expenses, lost profits, business interruption, lost
business information or other damages arising out the use or inability to use CNP. The license fee reflects
this allocation of risk.

CNP is not designed for situations where the results can threaten or cause injury to humans.

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Installing Cal NotePad

1. Insert CNP DISK 1 into the disk drive

2. Click on the START button on the task bar, select RUN, type A:\SETUP (Where A: is
your drive letter) then click OK

3. Follow the prompts which will install the application and necessary LabVIEW run time
support files.

4 Should you ever need to uninstall the software then use the Add/Remove Programs

option from the Control Panel.

Starting Cal NotePad

From a Standard Installation:

Click the START button

Highlight PROGRAMS

Select Isotech - Select Calpad

Protocol

The instruments use the "Eurotherm EI BiSynch Protocol"

If required, e.g. for writing custom software the technical details are available from our website
at, www.isotech.co.uk/refer.html

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EXPLODED VIEW OF CALIBRATION TUBE COVER (915/05)

ISSUE 04 01/05

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ACCESSORIES

The following options are available:-

915/01a Aluminium Equalising Block.

Containing four drilled pockets 8mmdiameter by 120mm deep in which
temperature sensors can be placed and is suitable for use with silicon oils. The
equalising block is suspended centrally within the calibration tube and is easily
removed.

915/01b Copper Equalising Block.

Dimensionally the same as 915/01a. This block is more suitable for use in
water and other liquids.

915/02 Liquid in Glass Thermometer Support Kit.

This assembly will hold up to 12 liquid in glass thermometers (maximum
diameter 12.7mm) radially and a centre mounted standard sensor. The
assembly may be rotated allowing systematic calibration. The assembly is
designed for partial or full immersion of thermometers.

915/03 Monocular and Support.

Useful for viewing and magnifying the liquid column within the thermometer
being calibrated. This ancillary piece of equipment is used in conjunction with

915/05 Calibration Tube Cover.

The cover consists of a square enclosure containing baffles and fits over the
calibration tube area insulating the circulating liquid from ambient air. Access for
temperature probes remains at the top of the enclosure. An equalising block
may also be supported from this assembly. Maximum operating temperature
180ºC.

915/07 Medium Temperature Silicon Oil.

Temperature Range 40ºC to 180ºC.
Supplied in 9 litre containers. Flash Point 300ºC.

915/08 High Temperature Silicon Oil.

Temperature Range 150ºC to 250ºC.
Supplied in 9 litre containers. Flash Point 315ºC.

915/09 Very High Temperature Silicon Oil.

Temperature Range 40ºC to 288ºC.
Supplied in 2 x 5 litre containers. Flash Point 288ºC.

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APPENDIX 1

USING THE ISOTECH HIGH STABILITY TEMPERATURE CONTROLLER

i, Isotech High Stability Controller

OPERATING INSTRUCTIONS

The ISOTECH HIGH STABILITY CONTROLLER has been designed to provide superior
stability with ease of use.

CHANGING SET POINT

The set point is modified utilising the three front panel keys.

To modify the set point first press "ALTER" once, the top left digit will flash which indicates that
the digit may be modified by pressing the "SET" key. The digit will step with each press of the
"SET" key. The first digit may be -, 0, 1 or 2 whilst the following digits may be in the range 0 ­9 which allows an
entry range of -99.99 to 299.99°C.

When the required value has been set or to move to the next digit then press the "ENTER" key.

After the fifth digit has been set then pressing "ENTER" will now cause all five digits to flash
showing the new set point or target temperature. To accept this new value press "ENTER"
again the display will now stop flashing. It is only when the display has stopped flashing that the
new set point is activated.

Or if you are unhappy with the new set point value instead of pressing "ENTER" as the display
flashes press "ALTER" which allows the set point to be changed again.

In use there may be a small offset (less than 1°C) between the set point and the measured
value this is quite normal. The measured value is to a large extent a measurement system
independent of the control loop. If you are aiming for a particular temperature, for example 50°C
and with a set point of 50.00 the actual temperature is found to be 50.06 then the set point may
be offset by 0.06, 49.94 in this case. Remember this is a comparison calibration bath.

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RS 232 OPERATION WITH THE ISOTECH HIGH STABILITY CONTROLLER

The controller has an RS232 serial communication interface which allows the set point to be
read and modified and also the measured value may be examined. The controller operates at
9600 baud, 8 data bits, No parity and 1 stop bit (9600,8,N,1).

To read the set point send the controller the command (as an ascii character) S.

To read the Measured value send the controller the command R.

To modify the set point send Cabc.de, where a is either 0, -, 1 or 2 and b to e are in the range
0 to 9. All zero digits must be sent. The complete string should be sent in one go, if the
controller receives the entire string in more than 80mS then it is ignored as are out of range
values.

Examples, the following strings are allowed,

1, C123.45 Set point will become 123.45
2, C-00.15 Set point will become 0.15

The following strings are not allowed and would be ignored,

1, C300.45 Out of range
2, C-0.15 A zero is "missing"
3, C100.0 A zero is "missing"

RS 232 Connections.

The standard 9 pin D connector is wired as follows,

Pin 2 Rxd Receive Data
Pin 3 Txd Transmit Data
Pin 5 Common

Other pins no connection.

RS232 operation with a Eurotherm Controller, see separate Eurotherm Manual.

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