Thermo Scientific Sarasota FD900, Руководство пользователя

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Thermo Fisher Scientific User Guide for Sarasota ID900, FD900, & PD900 Gas Density Meters
4-1
Chapter 4
Calibration
Warning
Refer to the warnings at the beginning of this manual.
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Warning
Refer to the local safety rules before commencing work.
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Density calibration is very specialized and is best performed at the factory
where accuracy and traceability to national standards are guaranteed. Also,
data is processed with factory approved algorithms to produce the best
accuracy calibration. However, if units cannot be returned for regular
calibration, complete the checks outlined below.
If you return a density meter, you must complete the Health and Safety
Clearance Form (provided at the end of Chapter 6). Failure to return this
form may result in the meter being returned.
Note
The tests below do not replace works calibration where fiscal
accuracy is required but are useful in checking that the transducer is
working correctly.
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Airr Checks
With the instrument clean and dry, check the reading of the sensor time
period on air (Tair). Connect the instrument to a power supply and a timer
counter to the signal terminal. Read the periodic time. The display will
read time period in microseconds.
Make necessary corrections according to the section below, and Tair should
correspond closely to the Tair value documented on the calibration
certificate for that unit.
Corrections
For Ni-Span C spools (maximum 75°C/167°F), the temperature coefficient
is negligible. No correction is needed for the air temperatures different
from the calibration temperature at which Tair was measured.
For high temperature instruments (above 75°C/167°F), measure the
temperature and correct for the difference from the Tair temperature on
the calibration sheet using the temperature coefficient of the spool. Refer to
“Temperature Correction at Check Points” later in this chapter.