YOKOGAWA DT450G Series, User Manual, Page: 33 / 41

<4. Operation>
4-6
IM 11K01C01-01E
4.3 Steady-state Operation
Proceed to steady-state operation after making sure there is no problem with the DT450G during
start-up.
Before going into steady-state operation, make sure the cover is securely attached to the
DT450G main unit. Moisture or corrosive gas entering into the DT450G may result in malfunction.
This section discusses the following topics concerning the handling of the DT450G during
steady-state operation.
• Examination of operating condition (carried out only at the beginning of operation)
• Shutdown
• Restart
4.3.1 Examining the Operating Condition
At the beginning of operation, examine the following points to ensure that the DT450G continues
to operate in its optimum condition.

Effects of External Noise, Etc.
If the DT450G is being affected by noise to such a degree that normal operation becomes
problematic, first make sure the DT450G is installed and wired correctly as instructed by this
manual. Then, take appropriate noise countermeasures.

State of Dust Accumulation
Accumulation of a large amount of dust on the sensor probe of the DT450G may adversely
affect its normal operation. If the measured value is found to be abnormal, remove the DT450G
and examine the state of dust contamination of the sensor probe. If the cause of the abnormal
measured value is dust accumulation, clean the sensor probe periodically. If you are using the
DT450G in a high-temperature or moist gas atmosphere, also examine the effectiveness of
air purge. If the amount of dust accumulating on the outlet of purge air is found to be gradually
increasing, increase the supply pressure of purge air. If condensation is observed around the
probe inlet, it is advisable that heat insulation measures be taken.
4.3.2 Shutdown
To shut down the DT450G, turn off the power switch installed in the power line. If the DT450G will
not be used for a prolonged period, only turn off the power switch without turning off the air-purge
line.
The air-purge line need not be left turned on if there is no flow of gas to be measured (provided
that the ambient humidity is not too high).
4.3.3 Restart
There is nothing in particular that needs to be done before restarting the DT450G. If the DT450G
has not been in use for a prolonged period however, make sure there are no abnormalities with
the sensor probe before you restart the DT450G. When there are no abnormalities with the
DT450G, it will come into steady-state operation in approximately 30 minutes after power-on.