Scanner 2000 Steam Mass Flow Transmitter ... - Spirax Sarco

Section 1 Scanner ® 2000 microEFM
Flow Rate and Fluid Property Calculations
The Scanner 2000 calculates flow rates and fluid properties for natural gas, steam and liquid flow. The
following descriptions identify the industry standards upon which these calculations are based.
Natural Gas
The Scanner 2000’s natural gas calculations and data storage conform to AGA-3, AGA-7, AGA-8, API 21.1,
and ISO-5167 industry standards. The flow calculations compensate for the effects of pressure, temperature,
and gas composition to calculate the volume of gas measured at specified base conditions. These calculations
typically require configuration of inputs including differential pressure, static pressure, process temperature,
and for AGA-7, a turbine meter input.
The integral multi-variable transmitter (MVT) is used to measure static pressure and differential pressure. A
4-wire, 100-ohm platinum RTD is recommended for measuring process temperature. Where temperature is
relatively constant, a fixed temperature value may be configured.
Orifice Plate (DP Input). The Scanner 2000 calculates natural gas flow rate from orifice plates using
calculation methods found in the AGA-3 or ISO-5167 measurement standards. The natural gas fluid
properties, such as density and compressibility, are calculated in accordance with AGA-8 (Detail and Gross
methods). Heating values are calculated in accordance with AGA Report 3, Part 3, Appendix F using the gas
properties defined in GPA 2145. Molar mass (molecular weight) calculations are also based on GPA 2145.
NuFlo Cone Meter (DP Input). The Scanner 2000 calculates natural gas flow rate from cone meters using
industry-recognized algorithms identified in the NuFlo Cone Meter User Manual. The natural gas fluid
properties, such as density and compressibility, are calculated in accordance with AGA-8 (Detail and Gross
methods). Heating values are calculated in accordance with AGA Report 3, Part 3, Appendix F using the gas
properties defined in GPA 2145. Molar mass (molecular weight) calculations are also based on GPA 2145.
Gas Turbine Meter (Frequency Input). The Scanner 2000 calculates natural gas flow rate from a gas turbine
meter using calculations found in the AGA-7 measurement standard. The natural gas fluid properties, such as
density and compressibility, are calculated in accordance with AGA-8 (Detail and Gross methods). Heating
values are calculated in accordance with AGA Report 3, Part 3, Appendix F using the gas properties defined in
GPA 2145. Molar mass (molecular weight) calculations are also based on GPA 2145.
Averaging Pitot Tube Meter (Annubar ® ). The Scanner 2000 calculates natural gas flow rate from an
averaging pitot tube meter using calculations found in the ASME MFC-12M-2006 measurement standard.
The natural gas fluid properties, such as density and compressibility, are calculated in accordance with
AGA-8 (Detail and Gross methods). Heating values are calculated in accordance with AGA Report 3, Part 3,
Appendix F using the gas properties defined in GPA 2145. Molar mass (molecular weight) calculations are
also based on GPA 2145.
Steam
The Scanner 2000’s saturated steam calculations compensate for the effects of pressure, temperature, steam
properties, and steam quality.
Orifice Plate (DP Input). The Scanner 2000 supports steam measurement based on AGA-3 or ISO-5167
flow rate methods for orifice plates. Fluid properties are calculated in accordance with the IAPWS Industrial-
Formulation 1997 (IF-97) standard. Temperature is calculated according to IF-97 for saturated steam, based
on static pressure. Therefore, an RTD is not required. The optional Chisholm and James wet correction
methods are supported for the measurement of vapor and fluid.
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