Fluid Components International GF90_GF92 - Manual (Page 6)

FLUID COMPONENTS INTERNATIONAL LLC http://www.fluidcomponents.com
GF Series Flow Meter Models GF90/GF92 2 No. 06EN003229 Rev. H
Technical
Specifications
The flow element consists of two pairs of thermowells of the same size, shape and mass. One pair contains
a platinum RTD and a heater element. The other pair contains one RTD. The RTD located next to the heater
element is called the active RTD. The other RTD is referred to as the reference RTD. Since the active RTD
is adjacent to the heater, the temperature at the walls of the thermowell are always above the temperature
of the process media. The temperature at the reference RTD is the temperature of the process media. When
the process media is flowing past the active RTD a quantity of heat is carried off into the flow stream. The
amount of heat taken from the active RTD is a function of the process media mass flow rate. A
∆ T exists
between the two pairs of thermowells and a proportional ∆ R exists between the active and the reference
RTDs. The ∆ R is measured by the flow transmitter. The relationship of ∆ T to the mass flow rate is
calculated by the flow transmitter and is converted into a signal or is sent to the flow transmitter's display.
Gas Mass Flow Measurement:
GF90: In ducts or pipes sizes with a minimum 2.0 inch (5.1 cm) nominal inside diameter.
GF92: In pipe lines or tubing sizes from 0.125 to 3 inches (0.3175 to 7.62 centimeters).
Flow Elements
Process Connection:
GF90: 1 inch male NPT standard. Flange connections and field retractable packing gland assemblies
available.
GF92: 3/4 inch female NPT standard. 1.0, 1.5, 2.0 and 3.0 inch male or female NPT, flange
connections available.
Insertion Length — GF90: Variable length. Specify insertion “U” length (dimension from the
process connection to the tip of the flow element) to extend the tip of the flow element 1 inch (2.5cm)
past the centerline of the process pipe.
Body Length — GF92: 7.25 inches (18.4cm) for 1 inch flow tubes; 12.0 inches (30.5 cm) for 1.5 to
3 inch (3.81 to7.62 cm) pipe spool pieces. Variable A-lengths available.
Flow Element Material: All wetted surfaces are 316 stainless steel with nickel braze. Corrosion-
resistant alloys are available with factory specified all welded construction or compatible brazes.
Flow Element Range:
GF90: 0.25 to 1600 SFPS for most gases (ft/sec at a standard temperature of 70° F and pressure of
14.7 psia) or 0.08 to 487.7 NMPS [m/sec at a normal temperature of 21.1°C and
pressure of 1.013 bar (absolute)].
GF92: 0.006 to 2000 SCFM for most gases (ft3/min at a standard temperature of 70°F and pressure
of 14.7 psia) or 0.01 to 3398 Nm3/h [m3/ hr at a normal temperature of 21.1°C and
pressure of 1.013 bar (absolute)].
Actual velocity for both the GF90 and GF92 must be limited to a maximum of 200 feet per second
(60.96 meters per second).
Temperature Range: -50° F to +350°F (-45° C to +176.7°C) with the standard temperature flow
element. The GF90 is available in a High Temperature Flow Element configuration for service
in process temperatures from -100° F to +850° F (-73.3° C to +454.4°C).
Operation Pressure: Up to 1000 psig [68.9 bar (gauge)].
Transmitter
Signal Output:
Analog: Two independent signal outputs available that may be field set from the following listed
selection:
4-20 mA, 600 ohms maximum load
0-10 Vdc, 5000 ohms minimum load
0-5 Vdc, 2500 ohms minimum load
1-5 Vdc, 2500 ohms minimum load
Digital: RS-232C (EIA-232) serial port.
Switch Points (Dual Alarms): The switch points may be field set by programming the GF90 or
GF92 to alarm at high, low or windowed flow or at high, low or windowed process temperature.