Teledyne 4700, Руководство по обслуживанию

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4700 Refrigerated Sampler Service Guide
Section 3 Refrigeration System
3-7
Figure 3-8 Validating temperature sensor operation (view from front)
3.3.2 CPU Temperature
Sensor
The electronics compartment is protected from moisture conden-
sation by an internal heater on the main CPU board. If the 4700
has been connected to AC power for at least half an hour, the
temperature within the electronics compartment should be
greater than the ambient temperature.
This temperature is measured by the sensor U16 mounted on the
board. See Sections 4.3.3 and 5.1.9 for instructions on how to
view the compartment temperature readings.
3.3.3 Sample Compartment
Thermometer
(optional)
Should there be a need to verify the temperature readings dis-
played by the control panel, it is important to read the temper-
ature as close as possible to the sensor inside the refrigerator.
To verify the temperature without a 24-bottle rack or locating
base, place a thermometer in a container of water in the right
rear corner of the refrigerator. The thermometer should sit in
front of the return air opening to the refrigeration system, but
not obstruct the air flow.
To verify the temperature with the 24-bottle rack, place the
refrigerator thermometer on the rack near bottles 20 and 21
(Figure 3-9). For samplers with the bottle locating base, place the
refrigerator thermometer between bottles three and four
(Figure 3-10).
The refrigerated compartment thermometer can be read after 30
minutes and compared with the displayed refrigerated com-
partment temperature (Section 5.1.8).