38 | Specifications
Controlled Rate Freezer
Specifications
Temperature Uniformity
Temperature uniformity is specified to be less than a standard
deviation of 2°C (up to the ‘freeze’ of the first vial) across a
matrix of 10 vials (1.2/2.0ml size) containing 1.0ml (± 2%)
each of distilled H
2
0. The temperature is to be monitored by
type ‘T’ thermocouples placed in the center of the liquid in
each vial with the vials distributed in standard racks and
holders as shown below (separately for each cabinet size).
Note that there are 5 each vials in the second rack from the
top, as well as the second rack up from the bottom, with the
‘Sample’ vial placed in the center of the top rack. Also, note
that the large cabinet uses a combination of the small and
mid-size rack and holder sets. Finally, a specific program
sequence, listed below, must run in order to collect the
uniformity data.
Figure 94. Rack and Holder Vial Placement for
each size chamber
Temperature Uniformity Profile With Cryo Bags
Temperature uniformity with 250ml cryo bags set up is
specified to be less than a standard deviation of 2°C (up to
the ‘freeze’ of the first cryo bag).
The temperature is to be monitored by type ‘T’
thermocouples placed on the canister surface under 250ml
cryo bag that is filled with 50ml (± 10ml) cryo media (DMEM) in
each bag with the cryo bags distributed in standard racks and
canisters as shown in
(separately for each cabinet
size).
Each standard rack contains 10 shelfs where each shelf is
loaded with a cryo bag inside a canister. 3 shelfs are
instrumented with type ‘T’ Thermocouples i.e., the second,
fifth and eighth shelf from the top, with the ‘Sample’ bag
placed in the top shelf.
Note:
Use Type ‘T’ ribbon probe thermocouple for
Sample bag.
•
17L cabinet uses 1 rack and 3 thermocouples.
•
34L cabinet uses 2 racks and 6 thermocouples.
•
48L cabinet uses 3 racks and 9 thermocouples as per
cabinet size.
Sample bag location also depends on the cabinet size due to
no.of racks per cabinet:
•
For 17L, 1 rack with sample bag on top shelf
•
For 34L, 2 racks with sample bag on top shelf of rack
closer to fan blade
•
For 48L, 3 racks with sample bag on top shelf of middle
rack
Figure 95. Cryo Bags in Standard Racks and
Canisters
Uniformity Profile
1. Hold 10.0min @25°C
2. 2.0°C/min C to 0.0°C
3. 0.0°C/min S to 3.0°C
4. Hold 10.0min @1.0°C
5. 1.0°C/min C to -5.0°C
6. 99°C/min C to -50°C
17L
(0.6 cu.ft.)
34L
(1.2 cu.ft.)
48L
(1.7 cu.ft.)
17L
(0.6 cu.ft.)
34L
(1.2 cu.ft.)
48L
(1.7 cu.ft.)
Sample bag Shelf location
(Type T ribbon probe)
Instrumented bag shelf location
(Type T thermocouple)
Un-instrumented bag shelf location
