Endress+Hauser Proline 200 - Page 187

Proline Prowirl F 200 PROFIBUS PA Technical data
Endress+Hauser 187
Steam is calculated based on the following factors:
• The measuring device calculates the density with full compensation using the pressure
and temperature measured variables.
• Assuming superheated steam conditions the measuring device calculates until the
saturation point is reached. The diagnostic behavior of the diagnostic message
S871 Near steam saturation limit is set to Off by default (ex works) →  145. This
diagnostic behavior can optionally be redefined as an alarm or a warning →  142.
Then the diagnostic message S871 Near steam saturation limit is triggered at 2 K
above saturation.
• The smaller of the following two pressure values is always used to calculate the density:
– The measured pressure which is either entered as the Fixed process pressure
(→  77) ≠ 0 bar abs. or read in via PROFIBUS PA
– The saturated steam pressure which is determined from the saturated steam line
(IAPWS-IF97/ASME)
• If the fixed process pressure = 0 bar abs. the measuring device only calculates on the
saturated steam curve using temperature compensation.
For detailed information on performing external compensation: →  101
Calculated value
The unit calculates the mass flow, heat flow, energy flow, density and specific enthalpy
from the measured volume flow and the measured temperature and/or the pressure based
on international standard IAPWS-IF97/ASME.
Formulae for calculation:
• Mass flow: m = q ⋅ ρ (T, p)
• Heat quantity: E = q ⋅ ρ (T, p) ⋅ h
D
(T, p)
m = Mass flow
E = Heat quantity
q = Volume flow (measured)
h
D
= Specific enthalpy
T = Process temperature (measured)
p = Process pressure
ρ = Density
2)
Pre-programmed gases
The following gases are pre-programmed in the flow computer:
Hydrogen
1)
Helium 4 Neon Argon
Krypton Xenon Nitrogen Oxygen
Chlorine Ammonia Carbon monoxide
1)
Carbon dioxide
Sulfur dioxide Hydrogen sulfide
1)
Hydrogen chloride Methane
1)
Ethane
1)
Propane
1)
Butane
1)
Ethylene (ethene)
1)
Vinyl chloride Mixtures of up to 8 components of these gases
1)
1) The energy flow is calculated as per ISO 6976 (contains GPA 2172) or AGA5 - in relation to the net
calorific value or gross calorific value .
2) From steam data as per IAPWS-IF97 (ASME), for the measured temperature and the specified pressure