Ultrasonic gas flow rate meter Energoflow GFA-202

Ultrasonic Gas Flow Meters Energoflow GFA-202

Overview

The main technical features of GFA-202 are:

The flow meter is powered by an built-in lithium battery having service life not less than 4 years.
The flow meter carries out direct measurement of temperature and pressure and on basis of the measured values of these parameters calculates the kinematic gas viscosity, which is then used for calculating correction coefficients of Reynolds number.

Flow meters are designed for :

measurement of the volumetric flow rate and volume of natural gas
measurement of temperature of gas
measurement of absolute pressure gas

Energoflow GFA-202 Flow Meters can be used as part of metering units of gas distribution points, industrial enterprises and communal service installation. Flow meters are designed for use in continuous operating mode and require minimal maintenance. Flow meters can be included to the measurement networks and control systems.

Flow meters has the protection marking "0ExiаIIBT4 Х " and can be installed indoors in explosions hazard zones. Flow meter consists of the electronic unit (EU) and flanged in-line section, having two pairs of inserted ultrasonic transducers as well as temperature sensor and pressure sensor.

TECHNICAL CHARACTERISTICS:

Parameters	Volume
Nominal diameter (DN)	from 50 to 300 mm (400 mm under special order)
Measurement range of gas flow velocity	from 0,15 to 40 m/s
Number of channels	2
Operating gauge pressure	1,6 MPa; 6,3 MPa, 10 MPa and 16 MPa
Limits of permissible relative error,of the Flowmeter, for range,of flow rate
from Qt to Qmax	± 1%
from Qmin to Qt (included)	± 2%
Pulse outputs: - two low-frequency (LF), to 20 Hz; - one high (HF), to 2 кHz;	Type “Dry Contact” Voltage from 5 V to 28 V, current - up to 20 mA
Temperature gas measurement	Resistive,Temperature ensor, Pt100, corresponding to standard DIN EN 60751, class A
Pressure measurement of gas	Tensoresistive absolutepressure sensor with temperatue correction
Absolute basic error of temperature measurement	± 0,15°С
Derived basic error of pressure measurement	Not more than,±,0,1 %
Communication channels	Interface RS-232/RS-485; Data transfer protocol, ModBus RTU; Data rate, upto 115200 bits/s;
Power supply	Buil-in lithium battery of capacity 2x19 A*h, (provides operation for 4 years)
Optional power supply from an external source	16 - 24 VDC; current consumption – up to 100 мА
Ingress,Protection of casing as per GOST 14254	IP67
Ambient Temperature	from -30°С to 55°С

Dependence of critical values of volume flow to meter size

DN, mm	Dimension type	Value of flow rate, m3/h
		Qthreshold	Qmin	Qt	Qmax
50	G160	0,2	1,0	8,0	250
80	G400	0,5	2,6	20,0	650
100	G650	0,8	4,0	33,0	1000
150	G1600	2,0	10,0	80,0	2500
200	G2500	3,4	17,0	133,0	4000
250	G4000	5,0	26,0	200,0	6500
300	G6500	8,0	40,0	325,0	10000
400	G10000	13	63,0	500,0	16000

Archive data:

hourly- for every preceding hour - size of archive 1488 records (62 days);
daily- for every preceding day - size of archive 730 records;
power on/off instances - size of archive 600 messages;
emergency situations - size of archive 1000 messages;
intervention - changing the adjustment parameters (size of archive 1000 messages).

Control software program is used for recording, viewing and changing the settings of the flow meter , recording and viewing of measurement data, as well as for reading data archive.

This program allows you to view the archive data and modify the flow meter settings via a PC monitor and then upload the archive data to a file on the flow meter. The flow meter provides protection of settings and archive data from unauthorized changing by restricting access through a system of passwords and hardware based protection of configuration from being overwritten.