Eppendorf New Brunswick -86 °C Freezers G - Manual (Page 23)

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HEF® and G -86 °C Freezers — Operating manual
If the freezer is turned off during the initial pull-down period, the alarm will activate 30 minutes
after switching it back on.
The factory-set temperature is -80°C.
6.1.4 Testing the alarm monitoring socket
The freezer is fitted with a remote alarm socket for testing power-fail and low battery alarms, and
for connection to an external building monitoring system or optional auto-dialer, (see Alarm
monitoring socket on p. 26). To test the alarm monitoring socket.
 Turn off (O) the ON/OFF circuit breaker.
This will test the POWER FAIL and ALARM output at the same time.
The battery must be switched on to test the POWER FAIL. The remote alarm facility provides
voltage-free contacts rated at 1 amp, 24 volts maximum.
6.1.5 Vacuum effect
After closing the freezer door, a vacuum may be created. Before the door can be opened again, it
may be necessary to wait two or three minutes for the vacuum to be released by the vent port. Do
not try to force the door. During the release of the vacuum, a slight hissing may be heard. In
order to minimize vacuum formation, the vent heater assembly has a spring-loaded plunger to
clear ice from the inside of the vent.
6.2 Programming the freezer
Set the freezer to any temperature within the range from -50 °C to -86 °C.
6.2.1 Setting operating temperature
To set the operating temperature for the freezer:
1. Press the LOCK key.
The LOCK lamp will illuminate, indicating the system is unlocked and parameters can be
changed.
2. Press the SET TEMP key.
Its indicator will flash and the display will indicate 0.
3. Using the numerical keys, enter a new temperature (from -50 °C to -86 °C).
The temperature selected will appear in the TEMPERATURE display.
4. When the correct temperature is displayed, press the E key to enter the data. To set the high
alarm setpoint skip to (see Setting high alarm setpoint on p. 24), step 2.
The SET TEMP lamp will go off.
5. Press the LOCK key to exit programming.
The LOCK lamp will go off and the freezer will return to normal mode.
Hint!
Be careful not to place a rack directly against the vent, as this will inhibit the plunger’s ability to
operate correctly (see Heated vent port on p. 29).
Hint!
All temperature setpoints are automatically negative °C.
Hint!
The LOCK lamp will flash if a lock code (password protection) is required, (see Changing lock
codes on p. 25).
Hint!
Press the C key to clear the display during programming.
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