Thermo Scientific Sarasota FD910, User Manual

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Thermo Fisher Scientific Sarasota FD910, FD950, & FD960 User Guide 4-1
Chapter 4
Calibration
A certificate of transducer calibration is supplied with each density meter.
Accurate density calibration requires special equipment. Thus, it is
recommended that you return it to the manufacturer for accurate
calibration. Consult Thermo Fisher.
If you return a density meter, you must complete the
Health and Safety
Clearance Form (provided in Appendix D). Failure to return this form may
result in the meter being returned.
If you do not return the instrument to the factory, you may perform
validation checks using one of the methods discussed below.
For measurement at atmospheric pressure of stable, nonvolatile process
fluid, a single tapping in the line near the density meter may be all that is
required. However, if the sample is at elevated pressure, possibly with
entrained gas or volatile components, high pressure pycnometry will be
required. This is a specialized technique beyond the scope of this manual.
The sample must be taken from the line carefully, at a rate that will not
significantly change line conditions of temperature and density.
Simultaneously record the density meter reading.
The density of the sample should be measured in a temperature controlled
environment using a hydrometer, pycnometer bottle, or a reference meter.
Compare the measured density to the recorded density meter reading.
Note that if the density meter is reading line density, either the sample
density must be measured at the same conditions or the density measured
at standard conditions (in the laboratory) and then corrected to line
conditions. Alternatively, the line density reading (from the density meter)
can be corrected to the laboratory reference conditions, but this will add an
uncertainty to the measurement. If the density meter is to be corrected
based on the laboratory results, a number of samples should be taken and
averaged before a correction is made.
Method 1: Online
Sampling