Oxford Instruments NanoScience Optistat CF User manual

© Oxford Instruments Nanotechnology Tools Limited, 2016. All rights reserved.
Oxford Instruments
NanoScience
Optistat CF
Operation Manual
System Manual /Issue 2.0 /September 2020

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Contents
1 Introduction ....................................................................................................................................5
1.1 Copyright................................................................................................................................. 5
1.2 Statement of intended use ..................................................................................................... 6
1.3 Restrictions on use..................................................................................................................6
1.4 Maintenance and adjustment................................................................................................. 6
1.5 Warranty ................................................................................................................................. 6
1.6 Acknowledgements.................................................................................................................6
1.7 Technical support.................................................................................................................... 7
2 Health and safety ............................................................................................................................ 8
2.1 Disclaimer................................................................................................................................ 8
2.2 Disposal and recycling instructions.........................................................................................8
2.2.1 WEEE ............................................................................................................................... 8
2.2.2 RoHS compliance ............................................................................................................ 9
2.3 Maintenance ...........................................................................................................................9
2.4 General hazards ...................................................................................................................... 9
2.4.1 Warning notices ..............................................................................................................9
2.4.2 Caution notices ............................................................................................................... 9
2.5 Specific hazards....................................................................................................................... 9
2.5.1 Hazardous voltages ......................................................................................................... 9
2.5.2 Low temperatures.........................................................................................................10
2.5.3 Pressure relief ...............................................................................................................10
2.5.4 Weight and lifting..........................................................................................................11
2.5.5 Asphyxiation..................................................................................................................11
2.5.6 Fire ................................................................................................................................11
2.5.7 Trip hazards...................................................................................................................12
2.5.8 Slip hazards ...................................................................................................................12
2.5.9 Temperature and voltage limits....................................................................................12
2.6 Safety equipment..................................................................................................................12
2.7 Risk assessments...................................................................................................................13
3 System description........................................................................................................................ 14
3.1 The Optistat CF cryostat........................................................................................................14
3.2 The sample probe .................................................................................................................15
3.2.1 Standard sample probe.................................................................................................16
3.2.2 Height and rotate sample probe...................................................................................17

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3.2.3 Precision height and rotate sample probe....................................................................18
3.2.4 Sample holders..............................................................................................................18
3.3 The cryogen transfer siphon .................................................................................................19
3.4 MercuryiTC temperature controller .....................................................................................19
3.5 System wiring........................................................................................................................ 19
3.6 Sensor calibrations................................................................................................................20
3.7 Gas flow pump and flow controller ......................................................................................20
3.8 System dewar........................................................................................................................ 20
3.9 Weights and dimensions.......................................................................................................20
4 System installation........................................................................................................................ 21
4.1 Unpacking the system...........................................................................................................21
4.2 System configurations...........................................................................................................21
4.3 Evacuating the outer vacuum chamber................................................................................23
4.4 Preparing the transfer siphon...............................................................................................23
4.5 Preparing sample probe wiring............................................................................................. 23
4.6 Exhaust gas connections .......................................................................................................23
4.7 Connecting to the MercuryiTC temperature controller .......................................................24
5 System operation.......................................................................................................................... 26
5.1 Preparations..........................................................................................................................26
5.2 Loading the sample probe and exchange gas.......................................................................26
5.3 Cooling the system................................................................................................................27
5.4 Operation below 4.2 K .......................................................................................................... 28
5.4.1 Transitioning from 4.2 K operation............................................................................... 29
5.5 Operation above 4.2 K .......................................................................................................... 30
5.5.1 Controlling at a ‘set temperature’ ................................................................................31
5.5.2 Operation above 300 K ................................................................................................. 32
5.6 Changing samples ................................................................................................................. 32
5.7 Warming up the system........................................................................................................33
5.8 Removing and replacing the OVC and radiation shield ........................................................34
5.9 Changing system windows.................................................................................................... 35
5.9.1 OVC windows ................................................................................................................ 35
5.9.2 Radiation shield windows .............................................................................................36
5.9.3 Sample space windows .................................................................................................37
5.10 Operating with liquid nitrogen..............................................................................................38
6 Service and maintenance..............................................................................................................39

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6.1 Rubber O-rings ......................................................................................................................39
6.2 Troubleshooting....................................................................................................................39
7 Optistat CF specifications..............................................................................................................41
7.1 Performance .........................................................................................................................41
7.2 Electrical power .................................................................................................................... 41
7.3 Physical..................................................................................................................................41
7.4 Technical exclusions and assumptions .................................................................................41
8 Appendices....................................................................................................................................42
8.1 Checking the wiring...............................................................................................................42
8.2 Cleaning and general care.....................................................................................................42

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1Introduction
This manual is designed to introduce you to the Optistat CF, manufactured by Oxford Instruments.
This manual contains important information for the safe operation of your system. We recommend
that you read this manual carefully before operating the system for the first time.
In addition to this manual for the Optistat CF, further manuals and documentation will have been
supplied with the system. These additional manuals and documents detail the components of the
system, as well as important safety information and are summarised in Table 1-1. Please ensure you
have reviewed the information supplied in all the manuals before you attempt to operate your system.
Documentation
Format
MercuryiTC manual
Electronic copy on USB
Practical cryogenics
Electronic copy on USB
LLT Siphon manual
Electronic copy on USB
Transfer siphon quickstart guide
Electronic copy on USB
VCU flowmeter manual
Electronic copy on USB
Safety matters
Electronic copy on USB
Optistat CF test results
Electronic copy on USB
MercuryiTC safety sheet
Hard copy
Table 1-1: Documentation supplied with the Optistat CF.
Please keep all the manuals supplied with your system and make sure that you periodically check for
updated information and incorporate any amendments. If you sell or give away the product to
someone else, please provide them with the manuals too.
1.1 Copyright
Copyright © Oxford Instruments Nanotechnology Tools Ltd, Tubney Woods, Abingdon, OX13 5QX, UK.
All Rights Reserved.
Copyright in this document is owned by Oxford Instruments Nanotechnology Tools Ltd. Any person is
hereby authorised to view, copy, print and distribute this document subject to the following
conditions: the document may be used for informational purposes only; the document may be used
for non-commercial purposes only; any copy of this document or portion thereof must include this
copyright notice.
This document is provided “as is” without any warranty of any kind, either express or implied,
statutory or otherwise; without limiting the foregoing, the warranties of satisfactory quality, fitness
for a particular purpose or non-infringement are expressly excluded and under no circumstances will
Oxford Instruments be liable for direct or indirect loss or damage of any kind, including loss of profit,
revenue, goodwill or anticipated savings. All such warranties are hereby excluded to the fullest extent
permitted by law.
Oxford Instruments will not be responsible for the accuracy of the information contained in this
document, which is used at your own risk and should not be relied upon. The information could include
technical inaccuracies or typographical errors. Changes are periodically made to the information
contained herein; these changes will be incorporated in new editions of the document.

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1.2 Statement of intended use
The equipment has been designed to operate within the process parameter limits that are outlined in
the user manual. The equipment is intended to be installed, used and operated only for the purpose
for which the equipment was designed, and only in accordance with the instructions given in the
manual and other accompanying documents. Nothing stated in the manual reduces the responsibility
of users to exercise sound judgement and best practice. It is the user’s responsibility to ensure the
system is operated in a safe manner. Consideration must be made for all aspects of the system’s life-
cycle including, handling, installation, normal operation, maintenance, dismantling, decontamination
and disposal. It is the user’s responsibility to complete suitable risk assessments to determine the
magnitude of hazards.
The installation, usage and operation of the equipment are subject to laws in the jurisdictions in which
the equipment is installed and in use. Users must install, use and operate the equipment only in such
ways that do not conflict with said applicable laws and regulations. If the equipment is not installed,
used, maintained, refurbished, modified and upgraded as specified by the manufacturer, then the
protection it provides could be impaired. Any resultant non-compliance damage, or personal injury
would be the fault of the owner or user.
Use of the equipment for purposes other than those intended and expressly stated by Oxford
Instruments, as well as incorrect use or operation of the equipment, may relieve Oxford Instruments
or its agent of the responsibility for any resultant non-compliance damage or injury. The system must
only be used with all external covers fitted.
1.3 Restrictions on use
The equipment is not suitable for use in explosive, flammable or hazardous environments. The
equipment does not provide protection against the ingress of water. The equipment must be
positioned so that it will not be exposed to water contact.
1.4 Maintenance and adjustment
Only qualified and authorised persons should service or repair this equipment. Under no
circumstances should the user attempt to repair this equipment while the electrical power supply is
connected.
1.5 Warranty
The Oxford Instruments customer support warranty is available to all our customers during the first
12 months of ownership from date of delivery. This warranty provides repair to faults that are a result
of manufacturing defects at Oxford Instruments NanoScience.
1.6 Acknowledgements
All trade names and trademarks that appear in this manual are hereby acknowledged.

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1.7 Technical support
If you have any questions, please direct all queries through your nearest support facility (see below)
with the following details available. Please contact Oxford Instruments first before attempting to
service, repair or return components.
System type:Optistat CF
Serial number: The Sales Order (SO) number and/or other identifiers of your system.
Contact information: How we can contact you, email/telephone details.
Details of your query: The nature of your problem, part numbers of spares required, etc.
Europe, Middle East, Africa and India (EMEAI)
OINS, Tubney Woods, Abingdon, Oxon, OX13 5QX, UK
Tel: [phone] (sales)
Tel: [phone] (support)
Fax: [phone] (sales and support)
Email: nano[email protected] (sales)
Email: [e-mail] (service and support)
Web: www.oxford-instruments.com
Americas
OINS, 300 Baker Avenue, Suite 150, Concord, MA 01742, USA
Tel: [phone] (sales and support)
Fax: [phone] (sales and support)
Email: nano[email protected] (sales)
Email: ServiceNSA[email protected] (service and support)
Web: www.oxford-instruments.com
Asia
OINS, Floor 1, Building 60, No.461, Hongcao Road, Shanghai, 200233, China
Tel: [phone] (sales)
Tel: [phone] (support)
Email: nano[email protected] (sales)
Email: [email protected] (service and support)
Web: www.oxford-instruments.cn
Japan
OINS, IS Building, 3-32-42, Higashi-Shinagawa, Shinagawa-ku, Tokyo, 140-0002, Japan
Tel: [phone] (sales)
Tel: [phone] (support)
Fax: [phone] (sales and support)
Email: [e-mail] (sales, service and support)
Web: www.oxford-instruments.jp

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2Health and safety
Before you attempt to install or operate your system, please make sure that you are aware of all safety
precautions listed in this manual together with the warnings and cautions set out in other documents
supplied with the system.
All cryogenic systems are potentially hazardous, and you must take precautions to ensure your own
safety. The general safety precautions required when working with cryogenic systems are given in
Oxford Instruments' Safety Matters document. We recommend that all users should read this
document, become thoroughly familiar with the safety information provided and be aware of the
potential hazards.
It is the responsibility of customers to ensure that the system is installed and operated in a safe
manner. It is the responsibility of customers to conduct suitable risk assessments to determine the
nature and magnitude of hazards.
2.1 Disclaimer
Oxford Instruments assumes no liability for use of any document supplied with the system if any
unauthorised changes to the content or format have been made.
Oxford Instruments' policy is one of continued improvement. The company reserves the right to alter
without notice the specification, design or conditions of supply of any of its products or services.
Although every effort has been made to ensure that the information in this document and all
accompanying documents is accurate and up to date, errors may occur. Oxford Instruments shall have
no liability arising from the use of or reliance by any party on the contents of this these documents
(including this document) and, to the fullest extent permitted by law, excludes all liability for loss or
damages howsoever caused.
Oxford Instruments cannot accept responsibility for damage to the system caused by failure to
observe the correct procedures laid down in this manual and the other manuals supplied with the
system. The warranty may be affected if the system is misused, or the recommendations in the
manuals are not followed.
2.2 Disposal and recycling instructions
You must contact Oxford Instruments (giving full product details) before any disposal begins. It is also
important to check with the appropriate local organisations to obtain advice on local rules and
regulations about disposal and recycling.
2.2.1 WEEE
Oxford Instruments Nanotechnology Tools Ltd is a scheme member for end of product life disposal.
The scheme is operated by:
B2B Compliance, Emerald House, Cabin Lane, Oswestry, Shropshire, SY11 2DZ
Tel: [phone]
Fax: [phone]
E-Mail: [email protected]
Web: www.b2bcompliance.org.uk

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2.2.2 RoHS compliance
All the materials and components used in the manufacture of the Optistat CF are in compliance
without exemption with the EU Directive 2011/65/EU for Restrictions of Hazardous Substances
(RoHS). This is based on information provided by Oxford Instruments suppliers and is accurate to the
best of our knowledge.
2.3 Maintenance
Observe the necessary maintenance schedule for the system. Consult Oxford Instruments if you are
unsure about the required procedures. Only qualified and authorised persons must service or repair
this equipment.
2.4 General hazards
The following general hazards must be considered when planning the site for installation and
operating the equipment. Please take notice of the following relevant warnings.
2.4.1 Warning notices
Warning notices draw attention to hazards to health. Failures to obey a warning notice may result in
exposure to the hazard and may cause serious injury or death. A typical warning notice is shown
below.
WARNING
A warning triangle highlights danger
which may cause injury or, in extreme
circumstances, death.
2.4.2 Caution notices
Caution notices draw attention to events or procedures that could cause damage to the equipment,
may severely affect the quality of your measurements, or may result in damage to your sample or
measurement apparatus. Failure to obey a caution notice may result in damage to the equipment. A
typical caution notice is shown below.
CAUTION
Caution notices highlight
actions that you must take to prevent damage to the
equipment. The action is explained in the text.
2.5 Specific hazards
Safety information that applies specifically to the Optistat CF is provided in this manual. Where
additional components are supplied as part of a system, please read and follow all safety information
in the respective manuals and take additional precautions as necessary.
2.5.1 Hazardous voltages
HAZARDOUS VOLTAGE
Contact with hazardous voltage can cause death, severe injury or burns. Ensure that
a local electrical earth (ground) connection is available at the installation site.

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PROTECTIVE EARTH
The cryostat and any other parts of the system fitted with earthing points must always
be connected to protective earth during operation.
Parts of the system carry high voltages that can cause death or serious injury. Ensure that a local
electrical earth (ground) connection is available.
The electrical supply to the system must include an isolation box to ensure that mains electrical power
to the system can be isolated. The isolation box must allow the supply to be locked OFF but must NOT
allow the supply to be locked ON.
2.5.2 Low temperatures
COLD OBJECTS
Contact with cold objects and cryogens can cause serious injury to the skin. Skin may
adhere to cold objects. Ensure that any cryogenic or coolant delivery systems are
designed to prevent contact with the cold components.
Consider the hazards of low temperatures when planning the installation of the system. Proper safety
equipment, including hand and eye protection, must be made available to all personnel expected to
handle cryogenic liquids.
2.5.3 Pressure relief
CLOSED VESSELS
Closed vessels in the system are protected by pressure relief valves that exhaust
directly to atmosphere unless otherwise stated.
Do not tamper with any of the pressure relief devices fitted to the system or attempt to modify or
remove them. Also ensure that the outlets of the relief devices are not obstructed. The correct
operation of these relief valves is critical to the safety of the system. All closed vessels in the system
are protected by pressure relief valves, as described in Table 2-1.
Location
Description
Setting
Outer Vacuum Chamber
Relief valve to atmosphere
0.25 bar differential
Transfer Siphon
Relief valve to atmosphere
0.25 bar differential
Sample Space
Relief valve to atmosphere
0.25 bar differential
Table 2-1: Pressure relief valve information.
The system’s pumping valves for the outer vacuum chamber, sample space and transfer siphon have
in-built pressure relief plates, as shown in Figure 2-1. This allows the system’s vacuum chambers and
sample space to vent to atmosphere if it becomes over-pressurised. A restoring spring provides the
force required to re-seal the cap (red) automatically when the pressure drops.

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Figure 2-1: Example of the pressure relief valve on the Optistat CF.
Do not modify or tamper with these safety features in any way. Additionally, ensure that nothing can
restrict the movement of any of the pressure relief valves. The relief valves should not vent during
normal operation of the system.
2.5.4 Weight and lifting
HEAVY OBJECT
Incorrectly lifting heavy objects can cause severe injury. Use the appropriate lifting
equipment, operated by fully trained personnel, when handling heavy system
components.
Appropriate lifting equipment and Personal Protective Equipment (PPE) must be provided for the
duration of the system installation and should always be used whilst operating or moving the system.
2.5.5 Asphyxiation
ASPHYXIATION
Helium and nitrogen can
displace the oxygen from air and cause death by
asphyxiation. Ensure that adequate ventilation is provided.
Areas where these cryogens are stored or used must be well ventilated to avoid the danger of
suffocation. Oxygen level detection equipment should be installed in suitable locations to warn
personnel if the oxygen concentration falls below a threshold value. Take precautions to prevent
spillage of liquid cryogens.
2.5.6 Fire
FLAMMABLE GAS
Atmospheric oxygen can condense on cryogenically cooled objects. Oxygen can cause
flammable substances to ignite in the presence of heat or arcing, risking severe injury.
Rooms where cryogenic liquids are being handled must be designated as no smoking areas. While
liquid helium and nitrogen do not support combustion, their low temperature can cause oxygen from
the air to condense on surfaces and may increase the oxygen concentration in these areas. Oxygen
enrichment may cause spontaneous combustion.

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2.5.7 Trip hazards
TRIP HAZARDS
Poorly routed cables and pumping lines can be trip hazards and have the potential to
cause accidents. Such accidents can result in both damage to the system and injury
to personnel.
Where cables and lines are required, their routings should be considered when planning the
installation of the system. The cables and pumping lines of the system should be routed away from
walkways and away from areas of common use to prevent the hazards.
2.5.8 Slip hazards
SLIP HAZARDS
During normal operation, ice may form on parts of the system. Upon warm up, this
ice may melt and pool by the system. Water on the floor has the potential to cause
accidents. Such accidents can result in both damage to the system and injury to
personnel.
Drip trays should be placed appropriately around the system to catch any water runoff. Additionally,
warning signs should be placed around the system.
2.5.9 Temperature and voltage limits
The Optistat CF system is supplied with a MercuryiTC temperature controller. Safety features for the
temperature controller are described in the MercuryiTC manual supplied with the system. You should
ensure that you understand and comply with all safety warnings and cautions.
The MercuryiTC will have been set up in the factory in order to prevent you from accidentally
exceeding the maximum safe operating temperature of the cryostat and to limit the heater voltage to
a safe level. If you are planning to use an existing temperature controller, or a controller made by
another manufacturer, you should take the same precautions. The recommended values for the
temperature controller limits are shown in Table 2-2.
Control Limit
Control Value
Heater voltage
40 V
System temperature
510 K
Table 2-2: MercuryiTC system control limit values
TEMPERATURE & VOLTAGE LIMITS
If you do not safeguard the system with control limits, it is possible to cause serious
damage to the system.
2.6 Safety equipment
The following items are recommended for safe operation of any system:
•Personal protective equipment, including thermally insulated gloves, face protection, body
protection and protective footwear. Cryogens can act like water, soaking into clothing and
causing severe burns.

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•Hazard warning signs, barriers or controlled entry systems to ensure that personnel
approaching the system are aware of the potential hazards. This precaution is especially
important if your system includes a superconducting magnet.
•Oxygen monitors should be fitted in the laboratory to warn personnel if the concentration of
oxygen in the air falls below safe levels.
2.7 Risk assessments
It is the responsibility of customers to perform their own risk assessments before installing, operating
or maintaining the system. Risk assessments must obey regulations stipulated by the local regulatory
authority.

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3System description
The Optistat CF is a continuous flow, top-loading static cryostat and can be held at temperatures
between 3.4 K and 500 K using a MercuryiTC temperature controller. The sample is mounted on a
removeable probe which is cooled via exchange gas during operation. Up to five windows can be fitted
to provide optical access to the sample space. The sample space and radiation shields are thermally
isolated from the room temperature surroundings by the outer vacuum chamber (OVC).
Continuous flow cryostats like the Optistat CF do not have an internal reservoir of cryogens. The liquid
is supplied from a separate storage vessel through an insulated transfer siphon. It flows through a heat
exchanger around the sample space and out of the cryostat to the pump. A thermometer and heater
are mounted on the heat exchanger and these can be used with a temperature controller to control
the temperature of the heat exchanger. The sample is mounted in a separate space, which is filled
with exchange gas. This gas provides good thermal contact between the heat exchanger and the
sample. The flow of liquid which cools the cryostat does not come into direct contact with the sample.
In a static exchange gas system, you can adjust the atmosphere around the sample to suit the
experimental requirements. It is difficult to accidentally block the cryostat with frost while changing
the sample. If the pressure in the sample space is kept low enough, it is impossible for liquid to
condense around the sample, where it may interfere with optical measurements. In addition, if you
are doing high voltage experiments, you may be able to reduce the risk of an electrical discharge by
choosing a suitable sample space pressure.
A range of window materials are available, covering most of the electromagnetic spectrum. The inner
windows are sealed with copper gasket seals. The heat exchanger fitted to the Optistat CF has a
maximum operating temperature of 500 K. However, the maximum temperature the cryostat can
operate at is limited by the type of window fitted.
3.1 The Optistat CF cryostat
A schematic of the Optistat CF is shown in Figure 3-1. The main features of the cryostat are:
•The outer vacuum chamber (OVC) with 4 radial windows and one axial window.
•The transfer siphon arm.
•Sample space which can optionally be filled with exchange gas.
•Sample space entry port for probe loading.
•System heat exchanger with heater and sensor.
•Two pressure relief devices, one for the OVC and another for the sample space.
•A diagnostic 10-pin sealed connector for temperature control.

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Figure 3-1 Optistat CF cryostat schematic.
3.2 The sample probe
There are three variants of Optistat CF sample probe; standard, height and rotate, and precision height
and rotate. All these Optistat CF sample probes are fitted with a 10-pin seal as standard. The connector
is wired to a Harwin pin ring mounted just above the sample holder. The pin configurations for the 10-
pin seal and Harwin pin ring are shown in Figure 3-2 and Figure 3-3, respectively. The wiring
configuration for the sample rod is set out in Table 3-1.

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Figure 3-2: Pin configuration for the 10-pin connector.
Figure 3-3: Harwin pin ring configuration, as viewed from above.
Connector Pin
Harwin Ring Pin
Wire
Function
A
A
34 SWG Cu
Not Used
B
B
34 SWG Cu
Not Used
C
C
40 SWG Cu
Not Used
D
D
40 SWG Cu
Not Used
E
E
40 SWG Cu
Not Used
F
F
40 SWG Cu
Not Used
H
H
40 SWG Cu
Not Used
J
J
40 SWG Cu
Not Used
K
K
40 SWG Cu
Not Used
L
L
40 SWG Cu
Not Used
Table 3-1: Pin configuration for the sample probe 10-pin seal to harwin pin ring.
3.2.1 Standard sample probe
The standard Optistat CF sample probe is shown in Figure 3-4. The sample rod has fittings to attach a
sample holder to its base. When the sample rod is inserted into the Optistat CF, the sample holder
then sits between the system’s radial windows

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Figure 3-4: Standard Optistat CF sample probe.
3.2.2 Height and rotate sample probe
The Optistat CF height and rotate sample probe is shown in Figure 3-5. The sample rod has fittings to
attach a sample holder to its base. When the sample rod is inserted into the Optistat CF, the sample
holder then sits between the system’s radial windows. Additionally, the height and rotate sample
probe is fitted with a combined height and rotation adjustor, this allows for sample position
adjustments after the probe has been inserted and cooled within the Optistat CF.
Figure 3-5: Optistat CF height and rotate sample probe.

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3.2.3 Precision height and rotate sample probe
The Optistat CF precision height and rotate sample probe is shown in Figure 3-6. The sample rod has
fittings to attach a sample holder to its base. When the sample rod is inserted into the Optistat CF, the
sample holder then sits between the system’s radial windows. Additionally, the precision height and
rotate sample probe is fitted with a high precision rotation adjustor and micrometer. These
components allow for the precise positioning of samples after the probe has been inserted and cooled
within the Optistat CF.
Figure 3-6: Optistat CF precision height and rotate sample probe.
3.2.4 Sample holders
There are two sample holder options for the standard sample probe supplied with the Optistat CF.
The first is a plain reflectance sample holder, as shown in Figure 3-7 (Left). Several small samples may
be mounted on this sample holder at once. The second is a transmission sample holder which has a
15mm diameter aperture and includes a sample retaining clamp, as shown in Figure 3-7 (Right).
Figure 3-7: Reflectance sample holder (Left) and transmission sample holder (Right).

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3.3 The cryogen transfer siphon
The LLT transfer siphon is designed for ultra-low loss performance. The cold exhaust gas from the
cryostat flows along the tube, and the enthalpy of the gas is used to shield the flow of liquid from the
room temperature surroundings.
The LLT 600 is the standard transfer siphon option and is manually controlled. The LLT 650 is the
automated version of the LLT 600 which allows the gas flow rate to be optimised automatically using
the MercuryiTC temperature controller. For more information, please refer to the LLT Siphon manual.
3.4 MercuryiTC temperature controller
A MercuryiTC is used as the temperature controller for the system. The MercuryiTC monitors and
controls the thermometry of the system and adjusts the system heater voltage to hold the sample
holder at a defined temperature.
The MercuryiTC is configured with measurement cards in specific locations. This configuration is
detailed, along with the interconnecting cables, in Table 3-2.
Slot
Card Type
Function
Connection
Main Board
Sensor & Heater
Temperature Control
Diagnostic 10-Pin
1-3
Not used
n/a
n/a
Table 3-2: MercuryiTC configuration for the Optistat CF.
If the Optistat CF Dynamic has been supplied with an automatic LLT Siphon it will be fitted with an
additional ‘auxiliary’ card in MercuryiTC’s fourth slot. This auxiliary card controls the needle valve of
the LLT Siphon and connects to the siphons 7-Pin connector. For more information, please refer to the
LLT Siphon and MercuryiTC manuals.
3.5 System wiring
The Optistat CF cryostat is fitted with a 10-pin connector on the OVC top plate. This is used for the
connection to the sample space heater and sensor. The pin configuration for the 10-pin connector is
shown in Figure 3-8. The seal is held in place by a black nut, this nut should not be removed, unless
access to the wiring is required.
Figure 3-8: Pin configuration for the 10-pin connector.
The wiring configuration for the temperature control connector is set out in Table 3-3, as per the pin
configuration shown in Figure 3-8.