Thermo Scientific Heracell 150i, Руководство по эксплуатации

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Operating Instructions | HERAcell® 150i / 240i
10 Maintenance 10 Maintenance 10 Maintenance
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50115191 A / 08.2009
10.3 Preparing the temperature calibration
To determine the exact measured value of the device-
integral temperature sensor, a temperature
comparison measurement has to be performed every
three months.
If a major temperature deviation is found during this
check, a temperature calibration is required.
During this process, the temperature control of the
device is set to the value measured during the
temperature comparison measurement.
Use a calibrated measuring instrument with an
accuracy of > ± 0.1°C for this test. To minimize
temporary temperature fluctuations during the
measurement, the measuring instrument is placed
into the work space in an isothermal container (e.g. a
bowl filled with glycerol). The center of the work space
is the reference location for the comparison
measurement.
Isothermal container:
Do not use a container filled with water as
isothermal container as the evaporation of
water will result in a lower temperature
reading.
Excessive work space temperature:
Excessive work space temperature after
the calibration can be reduced by leaving
the doors open for approx. 30 seconds.
Comparison measurement procedure:
1. Turn the device on using the power switch.
2. Set the temperature set value and allow the
device to be heated. This may take up to several
hours.
3. Place the measuring instrument [3] onto the
center area of the work space.
Alternatively, a temperature sensor may be
positioned in this location. Route the connecting
cable either through the measurement opening
[2] in the glass door or through the access port [1]
in the rear panel of the device.
Fig. 69: Preparing the temperature calibration