NEW BRUNSWICK SCIENTIFIC CO-150, Manual To Operations

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New Brunswick Scientific User’s Guide
3.7.1 Temperature Sensor System Alarms
There are four temperature sensors: two in the door and two in the chamber.
If any of these sensors should fail, the following message will appear:
°
C FAIL .
Because the incubator can no longer control temperature properly without the
failed sensor, the heating will switch off and the incubator will cool down to
room temperature.
If, however, a sensor fails but subsequently corrects itself, the temperature
control will restart and an alarm message will remain on the temperature side
of the display:
SAL ... (meaning Sensor Alarm).
This message can be cancelled by pressing any key.
3.7.2 Over-Temperature Cut-out & Alarm
This alarm only occurs if the chamber temperature exceeds the Temperature
Setpoint by 1°C or if one of the heating elements exceeds a specific activation
threshold. The activation threshold is set at the factory and cannot be
adjusted.
Following activation, the over-temperature cut-out and alarm system operates
in two sequential modes:
Mode 1: The over-temperature cut-out and alarm activates and cuts power to
the heating elements and the CO
2
control valve. The condition is shown on
the display by the message ºCt riP . When the chamber temperature has
fallen to the programmed setpoint, the system changes to Mode 2.
Mode 2: The control system then tries to maintain the chamber temperature
at the programmed level by switching the heating elements on and off, using
an emergency control method that is, however, less precise. The message
tAL . will flash on-screen to signal that an over-temperature fault occurred and
the incubator is being controlled by the emergency control system. This
message cannot be cancelled via the keypad.
Normal temperature control can be regained and the over-temperature cut-out
and alarm can be cancelled by reprogramming the temperature, opening and
closing the glass door, or switching the incubator off and back on.
If the problem persists, the alarm will recur; if this happens, please contact
your service representative or your distributor immediately.