VWR 5700 Series, Operating And Maintenance Manual

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ULT Freezer 2-1 VWR International
Section 2
Calibrate
Once the freezer has stabilized, the control probe may need to be
calibrated. Calibration frequency is dependent on use, ambient conditions
and accuracy required. A good laboratory practice would require at least an
annual calibration check. On new installations, all parameters should be
checked after the stabilization period.
Before making any calibration or adjustments to the unit, it is imperative
that all reference instruments be properly calibrated.
Plug a type T thermocouple reader into the receptacle located inside the
lower door (see Figures 1-4 and 1-6). Compare the control temperature
set point to the temperature of the measuring device.
1. Press the Mode key until the Calibrate indicator lights.
2. Press up/down arrow to match the display to calibrated instrument.
3. Press Enter to store calibration.
4. Press the Mode key to return to Run mode.
Startup - Allow 12 hours for the temperature in the cabinet to stabilize
before proceeding.
Already Operating - Allow at least 2 hours after the display reaches set
point for temperature to stabilize before proceeding.
Note During calibration, the temperature display will not be available.
s
If no keys are pressed for approximately 5 minutes while in calibration
mode, the system will reset to Run mode.
Calibrating the
Control Probe
Temperature Stabilization
Periods