TESTO 6681 Profibus, Инструкция по эксплуатации

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testo 6681
- 1.2 Product description
1.2.7 Parameters
The following parameters are displayed:
•
Relative humidity in %RH (technical)
•
Relative humidity in % WMO* (calculation according to the WMO
standard)
•
Temperature °C and °F
•
Dewpoint in °Ctd and °Ftd
•
Absolute humidity in g/m³ and gr/ft³
•
Degree of humidity in g/kg and gr/lb
•
Enthalpy in kJ/kg and BTU/lb
•
Psychrometer temperature in °Ctw and °Ftw
•
Water vapour partial pressure in hPa and "H
2
O (inch H
2
O)
•
Water content in ppm
vol
and % vol
•
Dewpoint of H
2
O
2
mixture in °Ctm and °Ftm
•
Mixture humidity H
2
O
2
in %RH
m
* It is possible that condensation appears as of a displayed humidity
starting from 70 % and is shown on the display. This unit is used in
meteorology, for example. According to the WMO, the Magnus
coefficient is used for sub-cooled water in the calculation of relative
humidity.
Calculated humidity variables correspond to the medium of
air. With other gases/gas compositions, deviations may
occur, e.g. with the enthalpy
1.2.8 Scaling
There are three types of min./max. values:
1 The measuring range
The maximum sensor performance is in this range. Values outside of
the measuring range are displayed via messages, for example.
Measuring range, see table (below).
2 Standard scaling
The output signals are assigned to this measuring range as standard:
- during delivery if no entries are made in the order code