Thermo Scientific Cryo 740 Series Operating instructions

Model 740 Series
Cryo Series
Liquid Nitrogen Storage System
Operating and Maintenance
Manual 7000740 Rev. 8

Thermo ScientificThermo Scientific
MANUAL NO. 7000740
8 24522/FR-1994 3/20/08 Updated electrical schematic to match AS400 ccs
-- -- 4/16/07 Added hook-up/connection artwork to Section 1 ccs
7 23299 3/7/06 Added cautionary note about the use of Teflon tape on valves. ccs
Thread sealant is recommended (page 4-1).
-- -- 6/30/05 Added accessory list ccs
-- -- 12/2/04 Clarified electrical specifications ccs
6 -- 10/29/04 Updated manual fill, LED information ccs
5 22025/SI-9266 7/29/04 Added caution to sensor height adjustments ccs
4 2043/FR-1620 6/17/02 Added lid strap info, Section 1.4 ccs
3 16746/SI-8022 10/16/00 Software change on cryo controller board FR740-05 aks
2 19496/FR-1440 9/7/00 Revise power cord attachment instructions ccs
1 18966/FR-1362 3/8/00 Chg probe removal procedure ccs
REV ECR/ECN DATE DESCRIPTION By
Preface
7000740r7 Cryo Series i
Model Voltage
740 120
741 230
742 120
743 230
744 120
745 230
746 120
747 230
Table 1. Models Covered by this Manual

Thermo Scientificii 7000740r7 Cryo Series Thermo Scientific
Preface
Important Read this instruction manual. Failure to read, understand and follow the instructions in this manual
may result in damage to the unit, injury to operating personnel, and poor equipment performance. ▲
Caution All internal adjustments and maintenance must be performed by qualified service personnel. ▲
Material in this manual is for information purposes only. The contents and the product it describes are subject to
change without notice. Thermo Scientific makes no representations or warranties with respect to this manual. In
no event shall Thermo be held liable for any damages, direct or incidental, arising out of or related to the use of
this manual.
Note This equipment is Installation (Overvoltage) Category II, Pollution Degree 2. ▲
©2003 Thermo Scientific. All rights reserved.

Thermo Scientific 7000740r7 Cryo Series iiiThermo Scientific
Preface
Important operating and/or maintenance instructions. Read the accompanying text carefully.
Potential electrical hazards. Only qualified persons should perform procedures associated with this
symbol.
Equipment being maintained or serviced must be turned off and locked off to prevent possible injury.
Extreme temperature hazards, hot or cold. Use special handling equipment or wear special, protective
clothing.
Potential biological hazards. Proper protective equipment and procedures must be used.
Marking of electrical and electronic equipment, which applies to electrical and electronic equipment
falling under the Directive 2002/96/EC (WEEE) and the equipment that has been put on the market
after 13 August 2005.
This product is required to comply with the European Union’s Waste Electrical & Electronic
Equipment (WEEE) Directive 2002/96/EC. It is marked with the WEEE symbol. Thermo Scientific
has contracted with one or more recycling/disposal companies in each EU Member State European
Country, and this product should be disposed of or recycled through them. Further information on
Thermo’s compliance with this directive, the recyclers in your country and information on Thermo
products will be available at www.thermo.com.
✔Always use the proper protective equipment (clothing, gloves, goggles, etc.)
✔Always dissipate extreme cold or heat and wear protective clothing.
✔Always follow good hygiene practices.
✔Each individual is responsible for his or her own safety.

Thermo Scientific
iv 7000740r7 Cryo Series
Thermo Scientific
Preface
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7000740r7 Cryo Series vThermo Scientific
Table of Contents
Quick Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Connect LN2Transfer Hose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Attach Power Cord . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Connect Lid Strap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Connect Electrical Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Install Platform Riser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Install Optional Temperature Sleeve . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Fill Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Remote Alarm Contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Tank Switcher Plug-In . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Installation Validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Liquid Level Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
High and Low Level Sensors Adjustments . . . . . . . . . . . . . . . . . . . . .2-3
Gas Bypass Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Power Switch and Power Indicator . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Solenoid Switch and Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
General Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
Defrosting the Storage Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3
Section 1
Section 2
Section 3

vi 7000740r7 Cryo Series Thermo Scientific
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Mechanical Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Manual Liquid Level Check (Dip Stick) . . . . . . . . . . . . . . . . . . . . . .4-2
Control Board Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1
Accessory List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-2
Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-3
Electrical Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1
Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-1
Handling Liquid Nitrogen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1
First Aid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-4
Table of Contents
Section 4
Section 5
Section 6
Section 8
Section 7
Appendix

7000740r7 Cryo Series 1-1Thermo Scientific
Section 1 Quick Start-Up
Locate the storage container in a well ventilated area of the laboratory, with
adequate work space available for loading and unloading specimens. Allow
for adequate lid opening clearance.
Note Rear stabilizer feet are included on Model 740/741. ▲
This unit is designed to operate in the following environmental conditions:
Temperature: 5°C (41°F) to 40°C (104°F)
Humidity: 80% at <31°C, decreasing linearly to 50% at 40°C.
Altitude: < 2,000 meters (6,650 feet)
Warning Whenever working with liquid nitrogen storage equipment in a
closed environment, the use of personal O2detection devices is strongly
recommended. Refer to "Handling Liquid Nitrogen" in the appendix of
this manual. ▲
Figure 1-1. Unit Components

Attach Power Cord
1-2 7000740r7 Cryo Series Thermo Scientific
Section 1
Quick Start-Up
Liquid nitrogen is the only consumable material that is required for
operation. Only tanks meeting the following specifications should be used
with the unit's storage system:
Low Pressure Supply: . . . . . . . .22 PSIG maximum
Liquid Outlet Fitting: .1/2", 45-degree flared tube
A four-foot Nitrogen transfer hose with swivel end and fittings is sup-
plied with the unit.
Note A 6' long hose, with swivel, is supplied with Model 742/743,
744/745, 746/747. The use of a transfer hose longer than six feet will
degrade system performance. Contact the Technical Services Department
if an extended length transfer hose is required. ▲
The Cryo storage system requires a user-supplied, low pressure regulated
(22 PSIG) liquid Nitrogen supply. Anything higher than 22 PSI will
degrade performance of the Cryo storage container.
Connect the transfer hose between the low pressure, liquid outlet of the
liquid Nitrogen supply tank (22 PSIG) and the input flare fitting
connected to the solenoid valve at the back of the unit. Use an adjustable
wrench to tighten the swivel nut on each hose end and a second wrench
to steady the tank outlet.
After the transfer hose has been connected, open the supply tank valve
and check the connections for leaks.
1. Loosen screw located on the
power cord retainer. Spread the
power cord retainer.
2. Insert the power cord into the
power outlet module. Tighten
screw on the power cord
retainer.
3. Position power cord/module
assembly into outlet on unit.
Secure with screws on module.
Connect LN2Transfer
Hose
Figure 1-2. Power Cord Assembly

High LN2 Level Low LN2 Level
Vent - Do not connect or open
Alarm indicator
Fill Indicator
Liquid Level Indicators
Press Silence to
mute audible alarm
Control
Panel
No more than 6 ft
in distance
No sealer
Supply 22 PSI
Liquid
side
Open valve after both ends of the
transfer hose are connected
No sealer
Storage
Platform (optional)
Vent - Do not block!
ALARMS
High Level
Low Level
Silence
Fill Valve
Open
Power
Manual
Fill
Press to fill manually
Power Indicator

1-4 7000740r7 Cryo Series Thermo Scientific
Section 1
Quick Start-Up
Included with each unit (Model 746/747) is a lid strap for user
convenience.
1. Remove the protective white nylon screws from the areas indicated.
Discard these screws.
2. Install the strap as shown below, using the screws included with the
strap.
Warning Use only a grounded electrical receptacle. Failure to ground the
unit can result in serious injury from electrical shock. ▲
With the power switch turned OFF, connect the unit to a grounded
electrical outlet. See the tag on the back of the unit or the electrical
schematics included in this manual for voltage and full load amps.
The power switch on the back of the unit is the mains disconnect and is
also a reset-type circuit breaker. If an overload condition occurs, the built-
in circuit breaker will trip and the power switch will turn off. Turning the
power switch on resets the circuit breaker. If the circuit breaker trips again
within a short time period, the unit should be checked by a qualified
electrician.
Connect Lid Strap
Figure 1-3. Lid Strap
Connect Electrical
Supply

7000740r7 Cryo Series 1-5Thermo Scientific
Section 1
Quick Start-Up
Depending on the inventory control system chosen, install the platform
riser (if required) as shown in Figure 1-4.
Note In the liquid phase, the standard platform remains in the bottom of
the tank. ▲
A Temperature Sleeve is optional on all Cryo units. The sleeve is designed
to assist the temperature gradient within the unit so that in a normal vapor
phase setting of 3-5 inches of liquid, the temperature under the lid will
remain below -130°C.
When properly installed, the ends of the sleeve must be aligned with the
temperature probe at the rear of the tank and the square holes in the
bottom of the sleeve aligned with the fill and pressure ports.
It is imperative that the positioning of the sleeve not block either the fill or
liquid level tube orifices located at the bottom rear of the tank. Should
blockage occur, it will cause filling and liquid level indicator problems.
Install Platform Riser
Figure 1-4. Phase Storage
Install Optional
Temperature Sleeve

Remote Alarm
Contacts
Warning The lid must remain open throughout the initial filling of the
storage container. ▲
When electric power and LN2have been connected, open the lid and turn
on the power switch to begin filling the unit. Because the unit must go
from ambient room temperature to -196°C, considerable boiling of the
liquid nitrogen takes place, turning into super cooled nitrogen gas which
flows over the side of the open chamber. As this occurs, some frost occurs
around the top of the unit. This is normal during the initial fill with the
lid open and disappears once the unit has stabilized.
The storage container fills until the liquid Nitrogen reaches the high level
setpoint of five inches. During the initial fill, the low level alarm sounds
after 10 minutes unless the low level setpoint is reached. Silence alarm and
continue filling. The alarm clears when the low level is met. If low level
setpoint is not reached in one hour, the low level shutdown alarm activates.
See Section 2.
After the initial fill is complete, close the lid and allow the unit to stabilize
for 8 to 10 hours or overnight before changing the high or low level
setpoints or adding inventory.
Caution Some popping or cracking noises may be heard after the unit is
initially filled, and the lid is opened and closed the first few times. This is
normal and will quickly disappear. ▲
The liquid level controller has provision for a remote alarm system. A set
of remote alarm connections (RJ-11 style connector) are located on the
back of the cabinet (Figure 1-1). The remote alarm contacts are "dry"
contacts requiring the remote alarm system to have its own power supply.
The remote alarm contacts are activated immediately when AC power is
lost, or when the unit goes into high level alarm. The contacts are activated
after a thirty minute delay when the unit goes into low level alarm.
The contacts are marked COM = Common, N.O. = Normally Open,
N.C. = Normally Closed
1-6 7000740r7 Cryo Series
Thermo Scientific
Section 1
Quick Start-Up
Fill Unit
Figure 1-5. Contacts

7000740r7 Cryo Series 1-7Thermo Scientific
Section 1
Quick Start-Up
Installation Validation
The power outlet on the back of the cabinet provides line voltage to a tank
switcher if such equipment is used. Refer to Figure 1-1.
The following procedures tests key elements of the Cryo Freezer system
and verify the unit installation. These tests can be performed at the
operator's discretion. If any tests fail, contact the Service Department or
your local sales representative.
Power Switch
Turn the unit on with the power switch located on the back of the unit.
The Power LED indicator will light, as will the Fill, High and Low
Alarm, if applicable. The power switch is the mains disconnect for the
system.
LN2Supply
The source tank should indicate that it is full and the pressure to the
Cryo unit regulated at 22 PSIG. Check all connections for leaks.
Remote Alarm Contacts
With the contacts wired to a remote alarm, turn the unit on, wait a few
seconds, then turn the unit off. The remote alarm will activate immedi-
ately upon loss of AC power.
Manual Fill
The Manual Fill button is pressed and released to manually fill the tank
to the high level set point. The Fill indicator lights when active. The unit
can be filled past the high level set point by holding down the Manual
Fill button.
Dip Level Test
Note Factory settings are High Level - 5 inches (±1/2”), Low Level - 3
inches (±1/2”). ▲
Press and release the Manual Fill button so the unit will fill to the high
level set point and automatically shut off. Compare the High Liquid
level with the actual liquid level by using the plastic ruler provided with
unit.
Lower the ruler along the edge of the tank until it is at the bottom.
(When taking subsequent measurements, lower the ruler at this same
location.) When the LN2stops boiling, pull out the ruler. The actual liq-
uid level will be approximately one inch lower than the frost line on the
ruler.
Caution Some shrinkage of the ruler may occur depending on the level of
liquid nitrogen in the tank. ▲
Tank Switcher Plug-
In

Dip Level Test (continued)
Dip Tests should be made and the LN2level monitored about every
seven to ten days. Many labs continuously monitor and keep perma-
nent LN2consumption records.
Tank Switcher Outlet
Press Manual Fill while checking the tank switcher outlet with a volt
meter. Line voltage will be present when the unit is filling.
Alarm and LED Validation (not required at installation)
To perform the following test, it is necessary to remove the temperature
probes from the sensor tube. To adjust the probes, follow the procedures
in Section 2 of this manual. An LN2sample in a small insulated cup, or
the LN2supply already in the freezer can be used.
Warning Protective gloves, eye wear, and apron should be worn when
performing this test. ▲
1. Referring to Figure 1-6, remove the access panel and remove clamp.
2. Pull the probe sets toward the top of the tube until resistance is felt.
3. Power up the unit with the sensors out of the LN2. The solenoid valve
LED will light.
Caution When the probes are near the top of the sensor tube and
resistance is felt, it may be necessary to wait a few minutes to allow the
probes to warm up before removing them completely. ▲
4. The Low Level alarm LED and the audible alarm activate in about 10
minutes. The remote alarm contacts activate in about 30 minutes.
Note If the low level probe is not submerged in LN2within approximately
one hour, the low level shutdown alarm activates. See Section 2. ▲
5. To shut off the audible alarm, press the Silence button.
6. Submerge the Low Level Sensor into the LN2. The Low Level alarm
LED will go out.
7. Press the Manual Fill button. The solenoid LED lights. When the unit
is full, release the button, the fill stops, and the LED goes out.
1-8 7000740r7 Cryo Series Thermo Scientific
Section 1
Quick Start-Up
Installation Validation
(continued)
Alarm and LED Test

7000740r7 Cryo Series 1-9Thermo Scientific
Section 1
Quick Start-Up
9. Submerge the High Level sensor into the LN2, keeping the Low Level
sensor submerged. The solenoid LED will go out.
10. The High Level alarm LED, remote alarm contacts, and audible alarm
will activate in about 2 minutes.
11. Replace the probes and adjust if necessary. Refer to the instructions in
Section 2 of this manual.
Alarm and LED Test
(continued)
Figure 1-6. Alarms and LED Test

7000740r7 Cryo Series 2-1Thermo Scientific
Section 2 Operation
The liquid level controller installed on the
Cryo Series controls the liquid nitrogen level
between the low and high level sensors.
When the liquid level drops below the low
level sensor, the solenoid opens and the
refilling process starts. The refilling continues
until the high level sensor is reached, or the
solenoid switch is turned off.
If the controller detects an alarm condition,
an audible alarm sounds and the
corresponding High or Low Level alarm
indicator on the controller panel lights.
The audible alarm may be disabled by
pressing the Silence button. However, the
warning light and Alarm indicators remain
lit and audible alarm sounds every 30
minutes until the alarm condition is
corrected.
Note Low level shut down and open level
probe alarms can not be silenced. After the
alarm condition is corrected, the power
switch must be turned off, then on to clear
the alarm.
When Manual Fill button is pressed, the solenoid opens and unit begins to
fill. The Fill indicator lights.
Power indicator lights when power is applied to the unit and the switch is
turned on.
Figure 2-1. Control Panel

2-2 7000740r7 Cryo Series Thermo Scientific
Section 2
Operation
Liquid Level
Controller
The Cryo Series liquid level controller is a three sensor liquid level
controller, with high and low level alarm capabilities. The liquid nitrogen
is controlled between the low level sensor, and the high level sensor.
When liquid nitrogen drops below the low level sensor, the solenoid valve
will be activated, and liquid nitrogen will enter the tank and fill to the
high level sensor. If the low level sensor is not immersed in liquid nitrogen
within ten minutes, the low alarm system will be activated. The low alarm
LED will illuminate, as will the Alarm indicators and an audible alarm
will sound. The Silence key pad will silence the alarm, but the LED and
Alarm indicators will remain on and audible alarm will sound every 30
minutes for as long as the alarm condition exists.
If the low level sensor is not immersed in liquid nitrogen within one hour,
the unit will go into low level shut down alarm. When in this alarm state,
the following occurs: high level LED (off), audible alarm (cycle on and
off), all valves close and remote alarm contacts activate. To clear this alarm
(after the alarm condition is corrected), the unit power switch must be
turned off, then on.
The high level alarm signals an overfill condition, and is activated when
liquid nitrogen touches the high level alarm sensor and remains there for at
least two minutes. The Silence key pad will silence the audible alarm, but
the High LED and Alarm indicators will remain on and audible alarm will
sound about every 30 minutes for as long as the alarm condition exists.
Both alarm systems activate relay contacts that can be interfaced with most
remote alarm systems.
The Cryo Series liquid level controller continuously monitors the integrity
of the three liquid level sensors and associated wiring harness. If any one of
the sensors or the wiring harness should fail (open circuit), the unit will go
into open sensor alarm. When in this alarm, the following will happen:
alarms LED (cycle on and off), high and low level LEDs (off), all valves
will close and remote alarm contacts will activate. To clear this alarm (after
the alarm condition is corrected), the unit power switch must be turned
off, and back on.

7000740r7 Cryo Series 2-3Thermo Scientific
Section 2
Operation
High and Low Level
Sensors Adjustments
Factory default sensor settings are:
3-inch (±1/2”) - Low Level (start fill)
5-inch (±1/2”) - High Level (stop fill)
High Alarm set point is always 1 inch above the High Level setpoint
The following procedures are used to change the high and low level sensor
settings. Refer to illustration above.
1. Open the lid and remove the access panel cover on the right rear of
the cabinet.
2. Slide clamp off of the sensor wires.
3. The double tie-wrap on the sensor wires are the 3-inch low level and
the 5-inch high level settings.
Caution Allow probe to warm up for 30 minutes before removing from
tube. Pulling probe completely out of the tube when cold could damage
probe. ▲
Figure 2-2. Sensor Adjustment