NuAire NU-5710, Руководство по эксплуатации и обслуживанию

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OM0249 Page 38 of 64
Rev 4 June/2020
9.1 Chamber Temperature Calibration
The DH’s TEMPERATURE CALIBRATION MUST BE PERFORMED WITHIN 1
°
C OF THE PLANNED OPERATING TEMPERATURE.
Normally, 37.0 ° C is the most common set point. To initiate the procedure, turn on the incubator via the power switch on
the back panel. The default set point is 37.0 ° C; enter “Environmental Set Points” and adjust if desired Let the unit stabilize
for 8 to 12 hours. Use an independent calibrated instrument to check and calibrate the temperature.
Below is a description of calibration with a glass thermometer as one example for temperature calibration.
At the beginning of this procedure, set a calibrated glass thermometer in a glass beaker filled with water resting on a shelf
in the middle of the chamber. Do not place the glass beaker on the bottom of the chamber because it will result in a slightly
higher temperature reading due to the heater located on the chamber bottom. Placing the thermometer in glass beaker on
the middle shelf will give the most accurate results for calibration. The chamber should be humidified to avoid false low
readings due to evaporation of water from the flask. An accurate digital thermometer with a type K thermal couple could
also be used. No matter what instrument is used the measurement for this calibration should be taken in the middle of the
incubator chamber and in a stabilized condition.
When the unit has stabilized at the operating temperature, perform the following calibration procedure.
• Allow Incubator to stabilize at its given temperature set point in run mode.
• Enter “Service Settings” by means of your provided password.
• Press the Temperature Calibration button.
• Determine actual temperature within chamber by reading temperature measurement instrument.
• Select the number digits below the “Current Calibrated Sensor Reading” blue text button
• Input the current value displayed on your temperature measurement instrument and exit calibration.
Note: THE DISPLAY DOES NOT UPDATE IMMEDIATELY; IT TAKES 2-3 SECONDS
The chamber temperature calibration is complete. Let unit stabilize for 8 to 12 hours. If the chamber temperature (actual
thermometer) still does not match the display, perform the above procedure again. In some cases it might be necessary to
calibrate several times to achieve a stable condition due to ambient conditions of temperature and humidity within the
laboratory.
9.2 Door and Perimeter Duty Cycle adjustments for Temperature Calibration
The Door and Perimeter heaters are run on “Base Duty Cycle” calculations that are automatically increased or decreased to
run in accordance with the chamber temperature at a chosen set point. These duty cycles work in the controlled lab
environment but due to the many variables involved in temperature control there is also a manual adjustment. The heater
duty cycles can be adjusted to control condensation or to improve the temperature uniformity in the chamber.
The inner glass door and outer shell perimeter temperature calibration is best accomplished by running the Incubator for
a minimum of 24 hours with the water pan in place and perform the following calibration sequence, if required. Open the
outer Incubator door and look for general condensation. Some condensation on the glass door can be desirable as an
indication of adequate humidity in the chamber. Typically, one to two inches of condensation in the corners of the glass
door and/or gasket indicates a properly calibrated door and perimeter heater. The perimeter heater is located on the outer
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