Thermo Scientific 7452 Operating And Maintenance Manual page 22

Program User Specific
Profiles (cont.)
Thermo Scientific
Listed below are the available step types.
0.0 C/m C to 0.0C - Ramp chamber temperature at the specified rate
until the chamber reaches the specified temperature
0.0 C/m S to 0.0C - Ramp chamber temperature at the specified rate
until the sample reaches the specified temperature
For this particular function, when the cursor is in
the 'tens' position, pressing the up or down arrow
keys changes the available function. The cursor
must be in the 'units' position to change the rate
value. See Figure 2-3 for position location.
The monitored 'trip' temperature (either S for
Sample or C for chamber) can be changed by plac-
ing the cursor on the S or C and using the up or
down arrow keys.
Caution Steep ramp rates may cause chamber to be much colder/warmer
than the sample itself.
Thermal controllers are limited to +55°C and -185°C during steep
Sample ramps.
Note For chamber ramp steps, the
interior set temperature will ramp
1°C beyond the programmed
temperature to assure that the ramp
end point condition will be reached
under all operating conditions. For
example, if the chamber set point is
30°C, the controller will ramp to
31°C until the setpoint is reached.
Graph print-outs show this ramp
setting. ▲
▲
Figure 2-4. Ramp Settings
Section 2
Set-Up and Operation
Ramp Function
Number Position
0 0 . 0
Figure 2-3. Cursor
Positions
7007452 CryoMed Freezer 2-9