Controlled-Rate Freezer
PC Interface Software | 53
•
“
Chamber temp limit
” message appears when
chamber temperature is in between 55°C to 75°C or less
than -185°C.
•
“
Sample temp limit
” message appears when sample
temperature is in between 55°C to 75°C or less than -
185°C.
•
“
Warm Complete
” message occurs five minutes after
the chamber reaches 25°C during a warm cycle.
•
“
End of run: Click OK to Clear
” message appears five
minutes after the end profile step is reached.
•
“
Check LN
2
Supply!
” message appears when LN
2
is
ON for 30 minutes.
•
“
Heater Error
” message appears if the heater is
energized continuously (no active temperature control) for
60minutes.
•
“
Printer Buffer Full!
” message appears when the printer
storage buffer is full of run data (approximately 2 hours)
and no longer able to store the data for later printing.
•
Power failure at CRF!
-
“Power Failure” message appears when there is a
power failure in freezer.
-
The computer reports a Power Fail alarm and the
failure duration, if the failure duration is longer than 10
seconds.
-
The graph on the Run screen stops plotting when
there is a power failure and user will be prompted if
failure duration is more than 10 seconds.
-
If CRF experiences multiple Power Failures, the
graph on the run screen will show multiple Power
Failure alarms once the occurred alarm has been
cleared.
Figure 136. Power Failure
Power Failure Recovery
If the Controlled-Rate Freezer experiences a power
failure and the PC continues to operate:
The freezer continues to run the profile from the point of failure
when the power is restored. However, the freezer runs in
‘Stand-alone’ mode. All commands from the PC are ignored
except for profile status requests. The temperature data is
continually captured and plotted. The PC cannot clear alarms
or stop the Run. The UI of the freezer remains disabled.
The Run can be aborted at the freezer by pressing the Abort
button in the remote dialog box. The freezer resumes the
controller on the unit.
The Stop button on the Run screen ends data capture only.
The PC will report a Power Fail alarm including the failure
duration, if the failure duration is longer than 10 seconds. A
communication error message will display on the Run screen
during the freezer power failure.
If the PC experiences a power failure and the
Controlled-Rate Freezer continues to operate:
When power is restored to the PC and Windows reboots,
restart the freezer application.
Select Run from Main Menu. Select any profile, fill mandatory
fields (Data Tag and Run file name) and press Start Run.
Choose the COM port for the freezer that is running. A pop-
up message appears as shown in
and PC will
recover the Run data captured prior to its power failure,
continue Run in ‘Stand-alone’ mode. The graph on the Run
screen will show the gap when the PC was not
communicating. Graph plots the data before power failure
and continue to show the plotting of the continuous stream of
data from CRF there after.
Note:
If PC power failure occurs during wait step and CRF
goes to standalone mode, CRF doesn't get past the wait
step.
Figure 137. PC Power failure Recovery
Two Run screens can be restored for freezers that were
running during the PC power failure. Graph shows PCPF and
PCPR icon during power failure and power resume.