Leica Biosystems CM3050 S - Manual (Page 45)

45 Leica CM3050S – Cryostat
  H O M E  
5.7 Defrosting
The Leica CM3050 S has 3 (instruments without
specimen cooling: 2) different defrosting options.
- Automatic chamber defrost cycle
- Manual chamber defrost cycle
- Specimen head defrosting (manual) - instru-
ments with specimen cooling only.
Read the safety instructions in chapter
2.3.7 ‘Defrosting / frozen specimens’ !
Make sure to remove sensitive speci-
mens from the cryochamber before the
defrost cycle starts!
5.7.1 Automatic chamber defrost cycle
The automatic defrost cycle is carried out once
every 24 hours at the preselected time.
(For details see chapter 5.3.4 ‘Menu functions’ -
items 6 and 7).
During the defrost cycle, the corresponding as-
terisk is displayed inversely:
Once the defrost cycle is finished, the instru-
ment automatically switches back to refrigera-
tion.
Instruments with specimen cooling:
When defrosting starts, to avoid icing the speci-
men head is automatically adjusted to a tem-
perature between -10 °C and -5 °C, i.e. the set
temperature value is deactivated temporarily.
5. Operation
The specimen head refrigeration is automati-
cally switched back on when:
• at least 4 hours have passed since the de-
frost cycle was completed;
• and the actual chamber temperature devi-
ates less than 5 K from set value.
After the specimen head refrigeration has been
switched back on, the specimen head tempera-
ture rises briefly to +10 °C and then decreases
until it reaches the set value.
Switching specimen cooling back on immedi-
ately after defrosting:
As soon as the chamber defrost cycle is com-
pleted, specimen cooling can be switched back
on immediately:
• Press
until menu item ‘Set specimen
temperature’ is displayed:
• Press .
Specimen cooling is switched back on.
Despite the possibility of switching the
specimen cooling system back on im-
mediately after the automatic chamber
defrost cycle, we recommend the auto-
matic defrost cycle be set at a point in
time when the entire procedure can be
controlled automatically.
(See also information on menu items
6 and 7 in chapter 5.3.4 ‘Menu func-
tions’).
C T - 3 0 ° C O T - 3 5 ° C
S E T T E M P O T - 3 5 ° C
 
S E T T E M P O T - 3 5 ° C
 -