Fisher Scientific Isotemp 178L 120V, Руководство пользователя

Страница: 71 / 92

Maintenance
Preparing Temperature Calibration
Fisher Scientific Peltier Low Temp. Incubators 10-3
Preparing Temperature Calibration
To determine the exact measured value of the low temperature incubator’s integral
temperature sensor, a temperature comparison measurement must be performed every three
months. If a major temperature deviation is found during this check, temperature calibration
is required. During this process, the temperature controller of the low temperature incubator
is set to the value measured during the temperature comparison measurement.
Use a calibrated measuring instrument with an accuracy of < ± 0.1 °C (0.18 °F) for this test.
To minimize temperature variations during the measurement, put the measuring sensor in an
isothermal container (such as a bowl filled with glycerol) before placing it in the work space.
Use the center of the work space as the reference location for the comparison measurement.

Isothermal container

Do not use a container filled with water as an isothermal container
because the evaporation of water will result in a lower temperature
reading.

Excessive work space temperatures

Excessive work space temperatures after the calibration may be
reduced by leaving the doors open for approx. 30 seconds.
Comparison Measurement Procedure
1. Turn the low temperature incubator on using the power switch.
2. Set the temperature set value and allow the low temperature incubator to stabilize. This
may take several hours.
3. Place the measuring device in the center area of the work space. Alternatively, a
temperature sensor may be positioned in this location. Route the connecting cable
between the glass panel and the interior tank.
4. Close the doors.
5. Wait until the temperature value displayed on the measuring instrument has stabilized.
6. Use the temperature reading from the measuring device to calibrate temperature control
manually, as explained “Entering the Calibration Reference Temperature Manually” on
page 7-23 .