Phcbi MDF-U55V User manual

MDF-U55V

Please read the operating instructions carefully before using this product, and keep the operating
instructions for future use.
See page 42 for model number.
Operating Instructions
Ultra-Low Temperature Freezer

2
CONTENTS
INTRODUCTION ···································································· 3
PRECAUTIONS FOR SAFE OPERATION···································· 4
LABELS ON UNIT ··································································· 9
SYMBOLS ON UNIT································································ 9
ENVIRONMENTAL CONDITIONS ·············································· 10
INTENDED USE AND PRECAUTIONS········································ 10
FREEZER COMPONENTS
Main body ········································································· 11
Control panel ····································································· 13
INSTALLATION SITE······························································· 15
INSTALLATION ······································································ 16
START-UP PROCEDURE························································· 18
DURING/AFTER POWER FAILURE ··········································· 19
SETTING THE CHAMBER TEMPERATURE································· 20
LOCKING THE CHAMBER TEMPETAURE SETTING ···················· 21
SETTING THE ALARM TEMPERATURE
Setting the high-temperature alarm········································· 22
Setting the low-temperature alarm ·········································· 23
SETTING THE BUZZER SUSPENDED PERIOD ··························· 24
SETTING THE COMPRESSOR DELAY······································· 25
SETTING THE DOOR ALARM DELAY ········································ 26
REMOTE ALARM TERMINAL···················································· 27
MONITORING THE FREEZER STATUS······································ 28
ALARM FUNCTIONS······························································· 29
SAFETY FUNCTIONS······························································ 29
SELF-DIAGNOSTIC FUNCTIONS ·············································· 30
ROUTINE MAINTENANCE
Cleaning the exterior, interior, and accessories ························· 31
Cleaning the filter································································ 31
Defrosting the chamber ························································ 32
Checking the alarm operation ················································ 32
CALIBRATION ······································································· 32
REPLACEMENT OF WORN-OUT PARTS
Replacement of the battery for the power-failure alarm················ 33
Replacement of the fan motor················································ 33
TROUBLESHOOTING ····························································· 34
DISPOSAL OF UNIT
Recycle of battery································································35
Decontamination of unit ························································35
OPTIONAL COMPONENTS
Temperature recorder ·························································· 40
Back-up cooling kit······························································ 40
Small inner doors································································ 40
Inventory rack ···································································· 40
Drawers············································································ 40
SPECIFICATIONS ·································································· 41
PERFORMANCE ···································································· 42
SAFETY CHECK SHEET·························································· 43

3
INTRODUCTION
■Read the operating instructions carefully before using the product and follow the instructions for safe
operation.
■PHC Corporation takes no responsibility for safety if the product is not used as intended or is used with
any procedures other than those given in the operating instructions.
■Keep the operating instructions in a suitable place so that they can be referred to as necessary.
■The operating instructions are subject to change without notice for improvement of performance or
function.
■Contact our sales representative or agent if any page of the operating instructions is lost or the page
order is incorrect, or if the instructions are unclear or inaccurate.
■No part of the operating instructions may be reproduced in any form without the express written
permission of PHC Corporation.
IMPORTANT NOTICE
PHC Corporation guarantees this product under certain warranty conditions. However, please note that
PHC Corporation shall not be responsible for any loss or damage to the contents of the product.

4
PRECAUTIONS FOR SAFE OPERATION
It is imperative that the user complies with the operating instructions
as they contain important safety advice.
Items and procedures are described so that you can use this unit correctly and safely.
Following these precautions will prevent possible injury to the user and any other
person.
Precautions are illustrated in the following way:
WARNING
Warning indicates a potentially hazardous situation which, if not avoided,
could result in serious injury or death.
CAUTION
Failure to observe CAUTION signs could result in injury to personnel and
damage to the unit and associated property.
Symbols have the following meanings:
This symbol means caution.
This symbol means an action is prohibited.
This symbol means an instruction must be followed.
Be sure to keep the operating instructions in a place that is accessible to users of this
unit.

5
PRECAUTIONS FOR SAFE OPERATION
Do not use the unit outdoors. Exposure to rain may cause leakage and/or electric shock.
Only qualified engineers or service personnel should install the unit. Installation by unqualified
personnel may cause electric shock or fire.
Install the unit in a location capable of bearing the total combined weight (product + optional
accessories + stored items). After installing the unit, be absolutely sure to take precautions
to prevent the unit from falling over. If the unit is installed in a location which is not strong enough
or if the proper precautions are not taken, the unit may fall over and cause injuries.
Do not install the unit where there are high levels of moisture or where it may be splashed with
water. Installing the unit where there are high levels of moisture or where it may be splashed with
water may cause the insulation to deteriorate and give rise to leakage and/or electric shock.
Do not install the unit in a location where flammable or volatile substances are present.
Installing the unit in a location where flammable or volatile substances are present may cause
explosions and/or a fire.
Do not install the unit in a location where corrosive gases such as acids are present. Installing
the unit in a location where corrosive substances are present may cause electrical components to
corrode, leading to leakage and/or electric shock due to the deterioration of insulation resulting from
corroded electrical components.
Do not place this unit in a location where it is difficult to disconnect the power supply plug.
Failure to disconnect the power supply plug may cause fire in the event of a problem or malfunction.
Be absolutely sure to earth (ground) the unit to prevent electric shock. Failure to earth the
product may give rise to electric shock. If necessary, ask a qualified contractor to do this work.
Do not connect the earth wire to a gas pipe, water pipe or lightning rod when earthing the
unit. Earthing the unit improperly may give rise to electric shock.
Connect the unit to a power source as indicated on the rating label attached to the unit. Use
of any other voltage or frequency other than that on the rating label may cause fire or electric shock.
Never store volatile or flammable substances in this unit except in a sealed container. Such
substances may cause explosion or fire if they leak.
Never insert metal objects such as pins and wires into any vent, gap, or outlet on the unit.
This may cause electric shock or injury by accidental contact with moving parts.
WARNING

6
PRECAUTIONS FOR SAFE OPERATION
When handling harmful samples (for example, those which consist of toxic, pathogenic or
radioactive substances), install the unit inside a designated isolation facility. If the unit is
installed in a location which is not an isolation facility, there may be detrimental effects on both people
and the natural environment.
Before proceeding with maintenance or checking the unit, set the power switch to OFF, and
disconnect the power supply plug. Performing the work while power is still flowing to the product
or while the power supply plug is still connected may give rise to electric shock and/or injury.
Do not touch any electrical parts (such as power supply plug) or operate switches with a wet
hand. This may cause electric shock.
Wear protective gloves and mask during maintenance. Touching or inhaling chemicals or
aerosols from around the unit may be detrimental to health.
Never splash water directly onto the unit as this may cause electric shock or short circuit.
Never put containers with liquid on top of the unit as this may cause electric shock or short circuit
if the liquid is spilled.
Never damage the power supply cord or power supply plug (by breaking, adapting, placing
near a source of heat, bending with force, twisting, pulling, adding weight, or binding). A
damaged power supply cord or power supply plug may cause electric shock, short circuit, or fire
Never disassemble, repair, or modify the unit yourself. A high-voltage area is located inside the
unit. Any work carried out by unauthorized personnel may result in electric shock. Contact our
sales representative or agent for maintenance or repair.
Make sure the power supply plug is pushed fully in. Faulty insertion of the power supply plug
may cause electric shock or fire due to generation of heat. Never use a damaged power supply plug
or loose power outlet
Disconnect the power supply plug if there is anything wrong with the unit. Continued abnormal
operation may cause electric shock or fire.
Grip the power supply plug when disconnecting the power supply cord from the outlet.
Pulling the power supply cord may cause electric shock or short circuit.
Remove dust from the power supply plug periodically. Dust on the power supply plug may
cause insulation failure due to moisture and thus cause a fire. Disconnect the power supply plug and
wipe it with a dry cloth
WARNING

7
PRECAUTIONS FOR SAFE OPERATION
Disconnect the power supply plug before moving the unit. Take care not to damage the power
supply cord. A damaged power supply cord may cause electric shock or fire.
Disconnect the power supply cord when the unit is not in use for long periods. Keeping the
unit connected may cause electric shock, leakage, or fire due to the deterioration of insulation.
If the unit is to be stored unused in an unsupervised area for a long period, ensure that children do
not have access and that doors cannot be closed completely.
Ask a qualified contractor to carry out disassembly and disposal of the unit. Leaving the unit in
a location that can be accessed by third parties may result in unexpected accidents (e.g. the unit may
be used for unintended purposes).
Do not leave the plastic bags used for packing in a place where they can be reached by small
children as this may result in unexpected accidents such as suffocation.
Never replace the battery for the power-failure alarm yourself. Only qualified engineers or
service personnel should replace the battery.
When moving the unit, be sure to take precautions to prevent it from falling over. Moving the
unit with too much force may cause it to fall over, possibly resulting in injury. A qualified individual
must be assigned to supervise the safe movement and relocation of the unit.
As with any equipment that uses CO2gas, there is a likelihood of oxygen depletion in the vicinity of the
equipment. It is important that you assess the work site to ensure there is suitable and sufficient
ventilation. If lack of ventilation is suspected, then other methods of ensuring a safe environment
must be considered. These may include atmosphere monitoring systems and warning devices with
alarms.
Do not touch the condenser directly when the filter is removed for cleaning. Touching the
condenser may cause injury due to its hot surface.
WARNING

8
PRECAUTIONS FOR SAFE OPERATION
Never install the unit in a location where corrosive materials such as sulphur compounds are
likely to be generated (e.g. near a drainage facility). Corrosion of the copper pipes may result in
the deterioration and consequently the failure of the cooling unit.
This unit must be plugged into a dedicated circuit protected by a branch circuit-breaker.
Use a dedicated power source as indicated on the rating label attached to the unit. A
multiple-tap source may cause fire due to excessive heating.
Do not climb on top of the unit or put any objects on the unit. Falling from the unit may cause
injury; falling objects may cause damage to the unit
Never store corrosive substances such as acids or alkalis in this unit except in a sealed
container. These may be harmful to your health and may cause corrosion of internal components or
electrical parts.
Check the settings when restarting operation after a power failure or after turning the power off.
The settings may have changed as a result of stopping the unit. Stored items inside the unit may be
adversely affected when operation is resumed if the settings have changed.
To ensure the safety of the service engineer, submit a safety check sheet with the required
items filled out. This is provided as the photocopiable “Safety Check Sheet” at the end of these
operating instructions
CAUTION

9
LABELS ON UNIT
<Labels applied to the unit>
To avoid accidents, users are advised to read carefully the hazard labels found at key locations on the
interior and exterior of the unit.
Possible
Danger
Warning/Caution Type
Location of Danger
Warning/Caution Label Description of Danger
Personal
injury
Outer door latch
Exterior
Take care not to trap your hand in
the outer door latch.
Personal
injury
Sample
damage
Frostbite
Rise in chamber
temperature
Interior
To prevent frostbite, wear
protective gloves when handling
frozen items in the chamber.
Too much frost may cause
chamber temperature rise
resulting from incomplete door
close.
Sample
damage
Chamber temperature
Interior
A
lways use the outer door latch
when closing the outer door.
Improper closure may cause
the temperature to rise in the
chamber.
Sample
damage
Chamber temperature
Interior
Clean the filter once a month.
A dusty filter may cause poor
cooling performance.
SYMBOLS ON UNIT
The following symbols are attached to the unit. The table describes the meaning of the symbols.
This symbol is attached to covers that access high-voltage electrical components to
prevent electric shock. Only a qualified engineer or service personnel should be
allowed to open these covers.
This symbol indicates that caution is required. Refer to product documentation for
details.
This symbol indicates an earth.
This symbol means “ON” for a power switch.
This symbol means “OFF” for a power switch.

10
ENVIRONMENTAL CONDITIONS
This equipment is designed to be safe at least under the following conditions (based on the IEC 61010-1):
■Indoor use;
■Altitude up to 2000 m;
■Ambient temperature 5 oC to 40 oC;
■Maximum relative humidity 80 % for temperature up to 31 oC decreasing linearly to 50 % relative
humidity at 40 oC;
■Mains supply voltage fluctuations up to ±10 % of the nominal voltage;
■Transient overvoltages up to the levels of OVERVOLTAGE CATEGORY II;
■Temporary OVERVOLTAGES occurring on the mains supply;
■Applicable pollution degree of the intended environment (POLLUTION DEGREE 2 in most cases)
INTENDED USE AND PRECAUTIONS
This equipment is designed for low temperature storage of human cells, organs, plasma and DNA.
■The effective storage period depends on the sample condition and storage temperature. It is
necessary to determine the storage temperature and period suitable for the purpose.
■For live cells, a lower storage temperature should be required for long-term storage. It is
recommended to store the live cells at -130 oC or lower.

11
FREEZER COMPONENTS
Main body
13
Power supply cord
8 (inside)
5
1
Outer door
2
Magnetic door
gasket
6
9
3
Key hole
4
7
5
11
12
10

12
FREEZER COMPONENTS
1. Control panel: The chamber temperature and other alarms/functions can be set using the keys on the
control panel. The operational status can be checked on the temperature display and indicators [pages
13 and 14].
2. Inner door: This prevents cold air from escaping when the outer door is opened. Always be sure to
close the inner door securely before closing the outer door. The inner door can be removed for cleaning
or defrosting [page 32].
3. Outer door latch: Always lock the outer door latch when the outer door is closed. Provision has been
made for use of an additional padlock (not included).
4. Inner door latch: Always lock the inner door latch when the inner door is closed.
5. Access port <rear and bottom>: These ports are used to pass the sensor or cable of measuring
equipment, the sensor of a temperature recorder (optional), or the nozzle of a back-up cooling kit
(optional) to the chamber.
Replace the insulation and the rubber caps when the access port is not in use. Improper replacement
may cause an increase in chamber temperature or condensation around the access port.
6. Air intake vent: This is an air intake vent for circulating the air in the chamber. Do not block this vent.
Blocking this vent may cause unstable chamber temperature.
Do not insert fingers or other objects into this vent.
7. Levelling foot <bottom>: These are screw bolts used to install and fix the unit. Adjust the height of
the levelling feet by turning the screw bolts until the two front casters are away from the floor [page 16].
8. Filter <behind the grille>: This filter prevents dust from accumulating on the condenser. A dusty
filter may cause failure of the refrigerating device. Clean the filter once a month [page 31].
9. Space for temperature recorder: A temperature recorder (optional) can be mounted here so that the
chamber temperature can be recorded automatically [page 40].
Contact our sales representative or agent for the installation.
10. Power switch: This is the power switch of the unit. ON – “I” OFF – “○”
11. Remote alarm terminal: A remote alarm device (separately available) can be connected to this
terminal. The remote alarm relays the alarm to an operator in a remote location if the unit is un attended.
Refer to page 27 for details.
Contact our sales representative or agent to arrange the installation.
12. Battery switch: This is an ON-OFF switch for the battery for the power-failure alarm. Always turn
this switch on when the unit is operating to ensure that the power-failure alarm is working. Turn this
switch off when the unit is not used for a long period in order to protect the battery.
13. Fixture: Use the fixtures and secure the unit to a wall with a strong rope or chain [page 16].

13
FREEZER COMPONENTS
Control panel
1. Temperature display: In normal operation, this displays the current chamber temperature. During
temperature alarms, the display blinks [page 29]. When a self-diagnostic warning is triggered, a code is
displayed here [page 30].
2. Status monitor indicator (STATUS): The orange LED lamp lights up when the environmental
condition or status deteriorates or when the unit is not operating normally. Refer to page 28 for details.
3. Battery indicator (BATTERY): The orange LED lamp lights up to indicate that the battery needs to be
replaced (every 3 years). The orange LED lamp blinks to indicate that the fan motor needs to be
replaced (every 6 years). Refer to page 33 for details.
To arrange replacement, contact our sales representative or agent.
4. Door check indicator (DOOR): The red LED lamp lights up when the outer door is opened.
The buzzer sounds 2 minutes (initial setting) after the door check indicator lights up to indicate that the
door is open [page 29].
5. Alarm indicator (ALARM): The red LED lamp blinks in the event of an alarm [page 29].
6. Filter check indicator (FILTER): The orange LED lamp lights up and the buzzer sounds when
excessive dust has accumulated on the filter. When this indicator lights up and the buzzer sounds, clean
the filter following the procedure described on page 31.
“temperature display mode”: the status when the current chamber temperature is displayed on the
temperature display.
“setting mode”: the status when the input on the temperature display can be changed by pressing the
up arrow key for more than 5 seconds.
1 32 654

14
12 11 10 9 8 7
FREEZER COMPONENTS
7. Up arrow key ( ): During “temperature display mode”: pressing this key for more than 5 seconds
activates the setting mode. During “setting mode”: pressing this key allows the (blinking) figure on the
temperature display to be changed [pages 20 - 26]. The lock for the chamber temperature setting can
also be set to ON or OFF by pressing this key [page 21].
8. Scroll key ( ): During “temperature display mode”: pressing this key for more than 5 seconds
enables “locking of the chamber temperature setting” [page 21]. During “setting mode”: pressing this key
moves the user between the different (blinking) digits to be entered on the temperature display [pages 20
- 26].
9. Set key (SET): Pressing this key activates the chamber temperature setting mode [page 20]. Press
this key to enter the required value during the setting procedure [pages 20 - 26].
10. Status key (STATUS): By pressing this key when the status monitor indicator lights up, the status
code is displayed on the temperature display. This key is effective only when the status monitor
indicator is on. See page 28 for details.
11. Alarm test key (ALARM TEST): This key is used to check the operation of buzzer, alarm indicator
and remote alarm terminal [page 32].
12. Buzzer stop key (BUZZER): The buzzer is silenced by pressing this key when the alarm indicator
blinks and the buzzer sounds. (The remote alarm cannot be cancelled.)
“temperature display mode”: the status when the current chamber temperature is displayed on the
temperature display.
“setting mode”; the status when the input on the temperature display can be changed by pressing the
up arrow key for more than 5 seconds.

15
INSTALLATION SITE
This unit must be installed in a location which meets all the conditions described below.
If the unit is installed in a location which does not meet the conditions, its specified performance may
not be achieved or malfunctions and accidents may occur.
■A location not exposed to direct sunlight
Avoid any location which is exposed to direct sunlight. Installing the unit in a location exposed to direct
sunlight may reduce its cooling performance.
■A well-ventilated (airy) location
In order to ensure ventilation, leave clearances of at least 10 cm around the unit (at the left, right, back,
and top). Blocking the ventilation may reduce the unit’s cooling performance or cause malfunctions.
■A location away from sources of heat
Avoid any location which is close to a major source of heat (such as a heater or boiler). Installing the
unit near a major source of heat may reduce the unit’s cooling performance.
■A location with minimal changes in temperature
Avoid any location where the ambient temperature is subject to sudden changes. If the unit is installed
in a location where the ambient temperature is subject to sudden changes, it will not be possible to
achieve a stable cooling performance.
■A flat surface where the floor is also capable of bearing the total combined weight (product +
optional accessories + stored items)
Install the unit on a flat surface which is even and which is capable of bearing the total combined weight
(product + optional accessories + stored items). If the unit is installed where the surface is uneven or
where the unit will be inclined at an angle, the unit will be unstable, and accidents or injuries may occur
and/or unnecessary vibration or noise may be generated.
■A location with minimal humidity
Install the unit in a location where the relative humidity is less than 80 % R.H. Installing the unit in a very
humid location may cause earth faults and/or electric shock.
■A location free of flammable or corrosive gases
Avoid any location exposed to flammable or corrosive gases. Flammable or corrosive gases can cause
explosions and/or a fire. Furthermore, corrosion of the electrical parts may cause the insulation to be
reduced and result in earth faults and/or electric shock.
■A location where nothing can fall onto the unit
Avoid locations where objects may fall onto the unit. Objects falling and hitting the unit may cause it to
break down or fail.

16
INSTALLATION
When installing the unit, follow the steps below to secure the unit properly, and also be absolutely sure to
earth the unit.
In addition, install an earth leakage circuit breaker (on the unit’s power supply side), which is mandatory
under the applicable laws and regulations.
1. Preparations after unpacking
Remove all the tape used to secure the doors and interior parts, and leave the doors open for a short
while for ventilation.
If any surfaces of the outer cabinet are dirty, wipe the surface using a cloth moistened with a diluted
neutral dish-washing detergent.
Using an undiluted solution of detergent may cause the unit’s plastic areas to crack. Follow the
directions on the detergent for details of dilution.
After wiping the unit using the diluted detergent, be absolutely sure to wipe the surfaces with a cloth
dipped in clean water to remove traces of the detergent. After this, be absolutely sure to wipe the
surfaces with a dry cloth, allowing the surfaces of the outer cabinet to dry out completely, and then
proceed with the installation.
Note:
Remove the cable tie that bands the power supply cord. Prolonged contact with the tie may cause
corrosion of the cord coating.
2. Securing and levelling the unit using the levelling
feet
Rotate the front levelling feet clockwise until the casters
are raised 5 mm to 10 mm above the floor surface [Fig. 1].
In addition, rotate the levelling feet slightly clockwise or
anticlockwise, and adjust them so that the unit is
completely level.
When the casters are raised from the floor surface, the
unit will be secured. If they are left touching the floor, the
unit may accidently move when its door is opened or
closed.
3. Securing the unit by using the fixtures
Use the fixtures on the rear panel of the unit, and secure
the unit to a wall with a strong rope or chain [Fig. 2].
Fixture
Fig. 2
Fig.1
Levelling foot

17
INSTALLATION
4. Preventing electric shock by earthing the unit
When installing the unit, be absolutely sure to earth (ground) it. Earthing is necessary to prevent
electric shocks resulting from deterioration of electrical insulations
This unit comes with a 3-pin plug having one earth pin. Earthing work is not required in the case of a
3-pin power outlet equipped with an earth contact.
If the power outlet is not a 3-pin outlet equipped with an earth contact, ask a qualified contractor to do
the earthing work.
5. Installing an earth leakage circuit breaker
Install an earth leakage circuit breaker (on the unit’s power supply side), which is mandatory under the
applicable laws and regulations.
Contact our sales representative or agent to arrange the installation of an earth leakage circuit breaker.

18
START-UP PROCEDURE
Follow this procedure for the initial operation of the unit and for consequent operations (after temporary
stoppage for cleaning, maintenance or moving) .
After a power failure, the unit will restart operation automatically with the same settings as before the
power failure [page 19]
1. Check that the following switches are turned off: [power switch, battery switch, switch of the optional
back-up cooling kit (if installed)] .
2. Connect the power supply cord to the dedicated power source with the appropriate rating with the
chamber empty.
3. Turn on the power switch .
When the power is switched on, the high-temperature alarm is activated. The alarm indicator and the
temperature display blink. (This is not a malfunction.)
The high-temperature alarm will be cancelled when the chamber temperature reaches the approximate
set temperature [(factory setting): -80 oC].
When operation of the unit is started in high ambient temperature, the filter check indicator may lights
up. The indicator will turn off automatically when the ambient temperature decreases.
4. Turn on the battery switch.
<Important>
Always turn the battery switch on when the unit is operating to ensure that the power-failure alarm is
working.
5. Set the desired chamber temperature [page 20].
The factory setting of chamber temperature is -80 oC.
6. Using the temperature display, check that the chamber temperature has cooled to the set temperature.
Check that the chamber temperature falls to the set temperature when the start-up after cleaning,
maintenance or moving.
7. Turn on the switch of the optional back-up cooling kit (if installed).
8. Press the alarm test key (ALARM TEST) to check the alarm operation.
The alarm indicator blinks and the buzzer sounds. The remote alarm is also operated.
The alarm indicator (ALARM) blinks and “E09” appears on the temperature display if the battery switch
is off.
9. Press the test switch of the optional back-up cooling kit (if installed) to check it is working.
10. Gradually place the material inside the chamber.
Putting a large amount of material into the chamber at one time causes the temperature to rise.
11. Set the alarm temperature [pages 22 - 23] and the buzzer suspended period [page 24], lock the
chamber temperature setting [page 21], and set the compressor delay [page 25], and door alarm delay
[page 26] as required.

19
DURING/AFTER POWER FAILURE
Display of chamber temperature during power failure
By pressing the buzzer stop key (BUZZER) during a “power-failure alarm”, the buzzer stops and the
chamber temperature is displayed on the temperature display for 5 seconds.
Check the chamber temperature as appropriate by pressing the buzzer stop key (BUZZER) during
power failure.
<Important>
The battery for the power-failure alarm has a limited lifespan. Replace the battery every 3 years. The
alarm may not be activated if the power fails and the battery has not been replaced regularly. Contact
our sales representative or agent to arrange replacement of the battery.
Operation check after recovery from power failure
After recovery from a power failure, the operation will resume automatically with the same settings as
before the power failure. There is no need to re-set. However, always check the operational
status after recovery.
The settings are memorized during power failure by nonvolatile memory.
<Important>
Upon recovery from a power failure, check that the unit restarts operation properly. Also check that
there are no changes to the settings.

20
SETTING THE CHAMBER TEMPERATURE
Set the chamber temperature as required to keep the stored material at an appropriate temperature
for a long period of time.
Setting range of chamber temperature: between -90 oC and -50 oC
Initial setting (factory setting): -80 oC
The guaranteed minimum chamber temperature is -86 oC at an ambient temperature of 30 oC with no
load, although the set value for the chamber temperature can range from -90 oC to -50 oC.
For example, to change the setting of chamber temperature to -75 oC
(The following is only an example. Choose the actual setting according to the desired chamber
temperature.)
Operation Key operated Display after operation
1
Plug-in the power supply plug and
turn on the power switch.
(only when start-up of unit)
---- The current chamber temperature
blinks.
2 Press the “Set” key once. SET
The current setting (-80) is displayed
and the first figure (8) blinks.
3
Press the up arrow key (as many
times as needed to reach the
desired figure).
The display changes from -80 to -70.
4 Press the scroll key once. The second figure (0) starts to blink.
5
Press the up arrow key (as many
times as needed to reach the
desired figure).
The display changes from -70 to -75.
6 Press the “Set” key once. SET The new setting is memorized and
the current chamber temperature blinks.
The unit will return from setting mode to temperature display mode automatically after 90 seconds if no
key is operated (auto-return function). In this case, the setting is not changed.