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CS200
Control Systems
Controller
Operation
has occurred. This occurs because the control cannot differentiate between a very high resistance (when a
thermistor is in LN
2
) and an infinite resistance (when an open circuit appears in the level sensing circuitry).
Alarms and Error Conditions
The CS200 SERIES Control System control monitors many different conditions in the freezer and has a full
complement of alarms associated with these different conditions. As alarms occur, they trigger an audible tone
as well as a flashing red light on the status wheel. A remote alarm relay is also triggered following a user-
designated period of time, after the error condition occurs, if it is not corrected. In addition, the error condition
is displayed on the top line of display until the error condition is corrected. When an error occurs, the audible
alarm may be muted by pressing the designated button. The audible alarm will then be silent until activated
by a new error condition or the alarm is not corrected by the time the retrigger timer expires. A red light will
continue to flash until all errors are corrected. The remote alarm will be activated if the power is interrupted.
The High Temperature Alarm for Thermocouple #1
can be set through the menu system. This alarm is activated if
the temperature rises above the designated temperature. The alarm temperature can range from 0°C (32°F) to
-196°C (-320°F). It can also be disabled.
High Temperature Alarm for Thermocouple #2
can be set through the menu system. This alarm is activated if
the temperature rises above the designated temperature. The alarm temperature can range from 0°C (32°F) to
-196°C (-320°F). It can also be disabled.
System Alarms
A Low LN
2
Supply Alarm
can be set through the menu system. 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 LN
2
level reaches the
STOP FILL
sensor) or manually (the Stop Fill button is pressed). To change the timer
which activates this alarm, the menu options 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. This alarm is activated if the control detects a
sensor error. The possible choices are ENABLE or DISABLE. An open sensor can be confirmed through the
TEST
LEVEL SENSORS
option in the menu system.
A Remote Alarm Timer
can be set through the menu system. This is the amount of time 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.
Lid Open Too Long Alarm
can be set through the menu system. 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.
Thermocouple Alarm
can be set through the menu system. This alarm is activated if either thermocouple
experiences an open circuit. Your choices are ENABLE or DISABLE.
Test Alarms
Audible, visual and remote alarms
can be tested at any time through the menu system. Follow the instructions
on the display to hear the audible indicator of an alarm, to see the red status wheel flash or to trigger an
immediate remote alarm.
Logging
On-board memory logging is one of the most powerful and useful features of the CS200 SERIES Control
System. It provides a historical record for the freezer and a complete record of the environment in which
specimens are stored.
Summary of Contents for CS200
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