TW-357 REV E
System Alarms
The Low LN2 Supply Alarm can be set through the menu system (MENU, 3, 3, 1). This alarm is activated if the solenoid valve is not closed within a designated time period after a fill starts. The solenoid valve can be closed either automatically (the LN2 level reaches the STOP FILL sensor) or manually (the stop fill button is pressed) to stop the timer which activates this alarm. The possible choices for this alarm are None, 15, 30, 45, 60 minutes, 2 or 3 hours. This alarm does not correct itself until the fill is stopped (the solenoid closes).
The Sensor Error Alarm can be set through the menu system (MENU, 3, 3, 2). This alarm is activated if the control detects a sensor error such as an open sensor. The possible choices are ENABLE or DISABLE. An open sensor can be confirmed through the TEST LEVEL SENSORS option in the menu system (MENU, 2,1).
The Remote Alarm Timer can be set through the menu system (MENU, 3, 3, 3). This is the amount of time allowed to pass before the remote alarm relay is triggered if an error condition is not corrected. The possible choices are None, Immediate, 30 minutes, 60 minutes or 2 hours.
The Lid Open Too Long Alarm can be set through the menu system (MENU, 3, 3, 4). This is the amount of time the lid can be open before it triggers an alarm condition. The possible choices are None, 1, 2, 5 or 10 minutes.
The Thermocouple Alarm can be set through the menu system (MENU, 3, 3, 5). This alarm is activated if either thermocouple experiences an open circuit. The possible choices are ENABLE or DISABLE.
Test Alarms
The audible, visual and remote alarms can be tested at any time by the user through the menu system (MENU, 3, 4). Follow the instructions on the display to hear the audible “chirping” indicator of an alarm or to see the red LED flash or to trigger an immediate relay closure of the remote alarm.
Logging
The on board memory logging function is one of the most powerful and useful features of the KRYOS control. It provides a historical record for not only your freezer but also a complete record of the environment in which specimens were stored. Four separate logs are kept in the control:
1.System log – System logs are events that occur in the system such as lid opening/closing, LN2 filling
2.Error log - Error logs are
3.Temperature #1 log and Temperature #2 log - The two temperature logs are simply records of the temperatures recorded by the two thermocouples in the system.
The system and the error log each hold 4096 events while the combined temperature logs hold an additional 32,765 temperature events. All the logs are kept in
When an event (system, error or temperature) occurs, the control does two things with the data:
1.It enters the beginning or the conclusion of an event in the internal memory of the controller.
2.It sends the event data out the serial port of the freezer.
25
