Natural Gas Flow Computer Libraries

The natural gas flow computer libraries provide gas flow computer features for Wago PFC200 controllers.

The libraries perform orifice meter calculations according to the latest AGA-3 standard and gas properties are calculated in accordance with the latest AGA-8 standard. Events, alarms, and hourly history are maintained in a manner consistent with API 21.1. Data is extracted from the PLC using industry-standard .cfx files.

Feature Summary

The library uses the traditional concept of stations and meters. Stations describe gas properties and base conditions. Meters are assigned to Stations. Release 1 of the library supports orifice flow meters.

Meter Calculations	Orifice flow calculations	per AGA-3 (2013)
	Meter calculation frequency	Full calc once per second
	Calculated parameters	Volume, Mass, Energy
	Aggregated values available	Flow Rate, Current Hour Total, Last Hour Total, Today Total, Yesterday Total, Current Month Total, Prior Hour Total, Lifetime Total
Gas Property Calculations	Supercompressibility and density	per AGA-8 GERG (2017)
	Gas property calculation frequency	Full calc once per second
	Gas Property Calculation Frequency	Full calc during each PLC task cycle
Data Retention	per API 21.1	Periodic (hourly) history, events, alarms
	Periodic history retention	Configurable by meter. Minimum of 35 days – ranging to file system capacity
	Event retention	256 events per meter per “day”
	Alarm retention	64 alarms per meter per “day”
Data Transfer Method (Collection)	Via CFX files	Quorum/FLOWCAL Common File Exchange Format 8.5.0
		Minimum of 1 CFX per day
		CFX file stored on PLC file system (password protected)
	Manual/Local collection	Users with limited permissions and network access can copy CFX files from the PLC to another computer for transfer to hydrocarbon accounting system
	Remote/SCADA collection	Via secure FTP or SSH
Supported Meter Configurations	Orifice Meter	Flange taps
		Upstream static pressure tap
Contract Hour	Configurable	Per station
Units of Measure	Customary U.S. units only	Inches, psi, inches of water (68 degrees), degrees F, flow rates per day, volumes in MSCF, energy in MMBTU, mass in Mlbs
Diagnostics	Station calculations	Zs, Densitys, Zb, Densityb, Gas Gravity from Composition – corrected for standard conditions
	Meter configuration	Zf, Densityf, , Re, Cd, Ev, Y1, Fpv , Temperature-corrected Orifice size, Tube size, Beta
	Configuration validation features	Library validates configuration and provides error/warning messages
SCADA Interface	Implemented in PLC program
Configuration Loading/Transfer	Via text file	Library provides features to save configuration to file
		Library provides features to load all or part of the configuration from file
Power Loss Behavior	Configuration is retained	PLC persistent memory
	Flow History is retained	PLC persistent memory and file system
	Flow that occurs while PLC is not powered	Not measured
	When power is restored	Broken day is saved as CFX file and calculations resume
Licensing	Free for developer	Library file is free and can be added to any Wago e!COCKPIT instance
	Runtime Licensed	Library generates a site code on the PLC
		Beyond HMI, Inc. generates a license file from site code
		License file is installed on the PLC. License is perpetual but only usable on that PLC.
		Library features will execute for about 4 days after restart in trial mode. License must be installed before this period expires or data will be lost (unrecoverable).

Library Options

Library Name	Maximum Number of Meters	Maximum Number of Stations	Meter Types Supported	PLC Type	Programming Compatability
BhiLibGasFc_A	2	2	Orifice	Wago PFC200	e!COCKPIT
BhiLibGasFc_B	10	1	Orifice	Wago PFC200	e!COCKPIT
BhiLibGasFc_C	4	1	Orifice	Wago PFC200	e!COCKPIT

Licensing

The BhiLibGasFc library is available at no cost to e!COCKPIT users. The library uses runtime licensing. A license is required for each PLC which executes the library code. The program will run for approximately 4 days in trial mode before a license is required. Licenses must be purchased from Beyond HMI, Inc.