Fluid Components International ST75, ST75V User Manual

ST75/ST75V MASS FLOW METER

Installation and Operation Guide

Pre-Installation

Serial number Alignment

The ST75 and ST75V (Vortab) can be specified with integral or remote electronics. The flow element has a serial number etched into
the side of the HEX as shown on figure A. In addition, the tag on the enclosure will also denote serial number and model number. The
associated transmitter circuit card has a serial number noted on the board as shown in figure B. The flow sensor and transmitter
circuit have been calibrated as a matched set and should be paired together in service unless otherwise approved by a factory techni­cian.

Flow Direction Alignment

All sensor elements have a flow arrow indicator marked on the element assembly at the reference HEX flat. These flow elements have
been calibrated in a particular direction and are designed to be used in service with the flow arrow going in the same direction as flow
in the pipe stream. The flow element has been calibrated directly in the pipe tee or tube tee with careful consideration for orientation
and insertion depth. Removal from the tee section while physically possible is not recommended unless authorized by a factory
technician.

Flow Direction

FLOW

Serial Number

Figure A

Recommended Straight Run

To optimize flow meter system performance, FCI recommends installation with a minimum of 20 diameters upstream straight run and
10 pipe diameters of downstream straight run. Where straight run limitations significantly reduce the available pipe diameters, FCI
utilizes flow conditioners to produce a transferable flow profile from the calibration installation to actual field installations. FCI’s
proprietary AVAL software is available to make flow meter installation evaluations where straight run limitations are considered. See
Figure C for recommended installation.

FLUID COMPONENTS
INTERNATIONAL LLC

0.000 SFPS

32.2 DEGREES F

Figure B

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Figure C - Recommended Straight Run Condition

FLUID COMPONENTS INTERNATIONAL LLC ST75/ST75V MASS FLOW

Specifications

Media Compatibility:

Air, compressed air, nitrogen, oxygen, argon, CO2, ozone,
other inert gases, natural gas, and other hydrocarbon
gases, hydrogen.

Process Connection:

ST75: T-fitting [NPT female]: 1/4”, 1/2”, 3/4”, 1”, 1 1/2” or 2”

Tubing: 1/4”, 1/2” or 1”

ST75V: Female NPT, Male NPT, Flange

1/4”, 1/2”, 3/4”, 1”, 1 1/2” or 2”

Pipe/Line Size Compatibility:

1/4" to 2" [6 mm to 51 mm]

Instrument

ST75/ST75V Range:*

NPT Line Size ¼” ½” ¾” 1” 1 ½” 2”

Min. SCFM 0.04 0.13 0.22 0.35 0.85 1.40
Min [NCMH] [0.07] [0.22] [0.38] [0.59] [1.44] [2.38]
Max. SCFM 17.34 50.64 88.88 139.95 539.31 559.27
Max. [NCMH] [29.47] [86.04] [151.00] [237.78] [576.48] [950.20]

Tubing Line Size ¼” ½” 1”

Min. SCFM 0.01 0.05 0.25
Min [NCMH] [0.01] [0.09] [0.42]
Max. SCFM 3.02 21.15 99.08
Max. [NCMH] [5.14] [35.94] [168.33]

* actual range subject to gas type and specific conditions.

Accuracy:

ST75: ± 2% of reading, ± 0.5% of full scale

Optional: ± 1% of reading, ± 0.5% of full scale

ST75V: ± 1% of reading, ± 0.5% of full scale

Repeatability:

Temperature Compensation:

Standard: 40 to 100°F [4 to 38°C]
Optional: 0 to 250°F [-18 to 121°C]

± 0.5% of reading

Transmitter

Enclosure:

with either 1/2" Female NPT or M20x1.5 entries. Epoxy coated.

Output Signals:

(2) 4-20 mA user assignable to flow rate and/or temperature
(1) 0-1 kHz pulse for total flow

Communication Port:

to PDA with digital display models

Input Power:

DC: 18 Vdc to 36 Vdc (6 watts max.)
AC:

Operating Temperature Range:

Digital Display:

Two-line x 16 characters LCD. Displays measured value and
engineering units. Top line assigned to flow rate. Second line is
user assignable to temperature reading, flow totalizer or
alternating. Display can be rotated in 90° increments for
optimum viewing orientation.

NEMA 4X [IP67], aluminum, dual conduit ports

RS232C standard. Optional wireless IR

85 Vac to 265 Vac (12 watts max.; CE Mark Approval for 100

Vac to 240 Vac)

0 to 140°F [-18 to 60°C]

(Optional)

Turndown Ratio: 10:1 to 100:1

Agency Approvals:

ATEX/IEC Ex: II 2 G Ex d IIC T6...T3

II 2 D Ex tD A21 IP67 T90°C...T121°C

FM, CSA: Class I, II, III, Div. 1, Groups B-G

Class I, Div. 2, Groups A-D

CRN No.: 0F0303

Warranty:

One year

Flow Element

Installation:

ST75: In-line “T”, NPT or tube

Material of Construction:

probe element with Hastelloy-C thermowells; 316 stainless
steel NPT and tube fittings

Maximum Operating Pressure:

ST75: T-fitting [NPT female]: 240 psi [16.5 bar(g)]

Tube: 600 psi [41 barg]

ST75V: 240 psi [16.5 bar(g)]

Temperature:

Operating: 0 to 250°F [-18 to 121°C]

All-welded 316 stainless steel

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FCI Flow Meters may be installed with less than the recommended straight run, but may have performance limitations. FCI offers
VORTAB flow conditioners for use in applications that have significant straight run limitations. FCI uses the AVAL application
modeling software to predict meter performance in each installation. AVAL outputs are available to review prior to order placement
and will indicate performance expectations both with and without flow conditioning.

Flow Element Installation

Warning: The element is shipped specifically installed in the TEE oriented for inline installation. DO not remove the

sensing element from the TEE section during installation as calibrated performance can be effected.

Process Connections

The ST75 is available in pipe Tee configurations with NPT threads and tubing tees with a compression fitting suitable to clamp down on
concentric smooth surface tubing. The pipe Tee versions are standard 150# class rated tees suitable for service up to 150 PSIG at the
process temperature maximum of 250°F (121°C). The compression fitting material offered in the tube type configuration is rated for
250 PSIG service.

Pipe Tee Installation: With pipe extensions properly cut to length and the appropriate sealing materials used on the threads, install flow
element section by slowly rotating the configuration until firmly secure on the pipe section. Complete by installing opposing end pipe
section using care to firmly secure the element assembly either in a top mount or side mount position.

Tube Tee Installation: Clean all mating surfaces of the tee fitting, ferrules and the flow tube. Insert the flow tubing into the tee fitting.
Make sure the tubing rests firmly in the fitting counter bore seat. Tighten the nut on both ends of the tee by hand. Hold the fitting body
steady with a backup wrench, tighten the fitting nuts 1-1/4 turns, from hand tight baseline.

The ST75V is available in with flow tube configurations offering male and female NPT threads, ANSI flanges and DIN flanges. The
flow tube assemblies are rated for service up to 240 PSIG at the process temperature maximum of 250°F (121°C).

NPT Flow Tube Installation: With pipe extensions properly cut to length and the appropriate sealing materials used on the threads,
install flow element section by slowly rotating the configuration until firmly secure on the pipe section. Complete by installing opposing
end pipe section using care to firmly secure the element assembly either in a top mount or side mount position.

Flanged Installation: Clean all mating surfaces. Install appropriate sealing gasket between mating flanges. Tighten flange mating hard­ware to meet system sealing requiments.

See Appendix C for instrument outline dimentional details.

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Instrument Wiring

Before the instrument is opened to connect power and signal, FCI recommends that the following ESD precautions be observed:

Use a wrist band or heel strap with a 1 megaohm resistor connected to ground. If the instrument is in the shop setting, there should be
a static conductive mat on the work table or floor with a 1 megaohm resistor connected to ground. Connect the instrument to ground.
Apply antistatic agents such as Static free made by Chemtronics (or equivalent) to hand tools to be used on the instrument. Keep
high static producing items away from the instrument.

The above precautions are minimum requirements. The complete use of ESD precautions can be found in the U.S. Dept of defense
handbook 263.

Warning: Only Qualified personnel are to wire or test this instrument. The operator assumes all responsibility for safe
practices while wiring and trouble shooting.

FCI recommends installing and input power disconnect switch and fuse near the instrument to interrupt power during
installation and maintenance. Operator must have power disconnected before wiring.

See Safety instructions in Appendix A for the use of the ST75/ST75V series (AC and DC versions) in Hazardous Areas
Category II (Zone 1). Approval, KEMA 08ATEX0045/IECEx KEMA08.0012 for Category 2 GD protection Ex d IIC

T6..T1, Ex tD A21 IP67 T 90°C...Τ 121°C.

Input Power

The ST75/ST75V is available with both VDC and VAC input power configurations. Customers selecting VDC input power will
have a VDC input board only. Similarly, the VAC power board is supplied only with VAC powered units. In addition, both boards are
marked for either AC or DC power. Only connect the power specified on the wiring module as shown on Figures E and F respec­tively. Both VAC and VDC inputs require a Gnd wire to be connected. Input power terminal blocks are rated for 14-26 AWG.

To wire the instrument, ensure that the power is off. Pull the power and signal output wires through the port, using care not to
damage wires. FCI recommends using crimp lugs on the output wires to ensure proper connection with the terminal strip. Connect
the output wires as shown on figures E and F. Note that when the 4-20mA outputs are used simultaneously, a single return lead is
used.

Analog Output

4-20mA: The instrument is provided with a standard set up, of two 4-20mA outputs. Output 1 configured for flow and Output 2
configured for temperature. Terminal blocks rated for 14-28 AWG., 500 ohm max load per output.

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Pulse Output Activation

The ST75/ST75V provides a pulse output feature. Instruments ordered with volumetric or mass flow units will be factory set with
totalizer and pulse output activated. The mode can be changed in the field. Wiring either sink or source mode is shown in Figures E
and F below. Though only one configuration is shown with the VAC and VDC power supplies, the source or sink can be utilized with
either power input.

Sink Mode: 40 VDC Max, 150 mA max. Customer supplied power source
Source Mode: 15 VDC output, 50 mA max

VDC Power Connection

RS 232 Connection

VAC Power Connection

RS 232 Connection

Figure E

VDC Power

As Shown:

18-36VDC power connected with gnd
4-20mA connected for flow and temperature
Pulse Out in source mode

Note: In source mode, 15VDC Output max, 50mA max.

Power Disspation

AC Version

Power dissipation values under nominal conditions:
Instrument (Electronics + Sensor): 11.6 Watts
Sensor only: 0.25 Watts

Figure F

VAC Power

As Shown:

85-265 VAC power connected with gnd
4-20mA connected for flow and temperature
Pulse Out in sink mode

Note: In sink mode, 40VDC max, 150mA max customer
supplied power source.

DC Version

Power dissipation values under nominal conditions:
Instrument (Electronics + Sensor): 4.5 Watts
Sensor only: 0.25 Watts

Power dissipation values under maximum load conditions:
Instrument (Electronics + Sensor): 12 Watts

Sensor only: 0.30 Watts

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Power dissipation values under maximum load conditions:
Instrument (Electronics + Sensor): 6 Watts

Sensor only: 0.30 Watts

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Setup Interface

All parameters on this meter are set through the RS232 interface connection (P3 plug) or PDA IR interface. A jumper selection
determines which communication mode is active. The factory default communication mode is set for the RS232 interface. This
setting allows the instrument to be setup with either a FC88 hand held communicator or a computer. The FC88 is powered through the
meter and comes with the serial interface cable. If a computer interface is used, an adapter (RJ to 9 pin Computer Serial Port) is
required and may be obtained from FCI: Part No. 014108-02.

Using Windows Terminal (usually located in Accessories) execute the program by double-clicking on the Terminal Icon.

1. Go to Settings.

2. Click on Communication.

3. Set for COM1 or COM2, 9600 Baud, 8 Bit, and No Parity. Press OK

4. Press the ENTER key to see the Input Mode? prompt.

5. Enter any of the meters single letter commands to execute a function (reference complete function menu in Appendix B).

If the PDA IR interface is used for communication, then jumper JP5 needs to be moved to the alternate position, see Figure G and H.
See PDA IR Communication Interface section for more details.

An additional command line interface (CLI) is available through the RS232 port. This interface is accessed with the “Y” command
using a computer or FC88. The command line password is “357”. See Appendix B - Table 6 for command line details.

JP5

Figure G

JP5 factory set for RS232 interface

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Figure H

JP5 set for PDA IR interface

Infra Red Communications Window

Flow Rate, Total and Temperature Indicator

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Start up and Commissioning

1. Verify all Input power and output signal wiring is correct and ready for initial power start up.

2. Apply power to instrument. The instrument will initialize in the Normal Operation Mode. All outputs will be active and instru­ments with the display option will indicate flow with the factory set flow unit. Allow 10 minutes for the instrument to warm up
and come to the thermal equilibrium.

The following FC88 commands are typical commands that are used during start up and commissioning:

Command Name Description

T Normal Operation Mode All outputs are active

Z Flow Unit Set-Up Select Flow Units(4 English, 4

Metric)Pipe Dimensions

W Totalizer Enable/Disable

V Output Configuration Select one of 4 Configurations:

Pulse and/or AlarmPulse factor and/or
setpoint

F K-Factor (default=1) Flow factor

N Warm Re-set Re-initialize C/B

S Totalizer Menu Enables W menu (Option)

If the instrument is installed, and the process flow is zero, the instrument should indicate 0.000.

Flow Unit Modification

Example: SCFM Flow Units and 3 inch Sch 40 round pipe size set up:

Enter Display Description

Enter menu: > From Normal Operation Mode
Z E for English M for Metric > Flow Unit Set-Up menu

E

0=SFPS, 1=SCFM, 2=SCFH, 3=LB/H,
4=GPM #

1 R round duct or S rectangular> Select Standard Ft

R Select Round Duct

Dia.: 4.0260000
Change? (Y/N)>

YEnter value: #

3.068 3 inch Sch. 40 pipe I.D.

N

Y

area: 7.3926572 CMinflow: 0.0000000
Change? (Y/N)>
Maximum flow: 462.04
Enter to continue
Cmaxflow: 462.04
Change? (Y/N)>

Y#

462.04

N

N

N

CMintemp (F): -40.00000
Change? (Y/N)>
CMaxtemp (F): 250.00000
Change? (Y/N)>
Percent of Range is: OFF
Change to ON?>
LCD Mult Factor x1
Change? (Y/N)>

N 100.0 SCFM

English units

/Min (SCFM)

3

Instrument will end up in Normal
Operation Mode

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RS232 / FC88

Menu Control and Organization

Most entries require at least two key strokes; a Capital letter and the [ENTER] key, or one or more numbers and the [ENTER] key. All
user entries begin at the input mode prompt “>”,except when the instrument is in the Main Function Mode (just press the desired
function letter and [ENTER] to make an entry).
Backspaces are made using the backspace [BKSP] key. Some entries are case sensitive between numbers and letters. Be sure the
SHIFT key is pressed to indicate the correct case. A square after the prompt caret indicates the FC88 is in lower case. A slightly
raised rectangle in the same spot indicates the FC88 is in the upper case.
It is recommended that the FC88 be plugged into the instrument before power is applied. If the FC88 is plugged in while the
instrument power is on and the FC88 does not respond, press [ENTER], if there is still no response Press [N] or cycle the power.

Note: The Zero and Span may be changed from the original calibration, provided the new values are within the original calibrated

range. i.e. If the original calibration was 1 to 100 SCFM (4-20mA), the new zero (4mA) must be equal to or greater than 1
SCFM, the new span (20mA) must be equal to or less than 100 SCFM.

Some entries require a Factory pass code. If this occurs contact FCI Field Service to continue programming the instrument. The
instrument will prompt the user when this is necessary. Do not change any parameters that require this code unless there is an absolute
understanding of the instrument's operation. The user can not exit some routines unless all entries are completed or the power is
recycled.

The top level of the menu is shown in Appendix B - Table 5. Enter the large letter in the tables below to activate a command. The user
may exit a command at any time entering “Q” [ENTER] in the menus: D, K, V, W, or Z.

C Calibration Information

Display only: A/D, Delta-R, Ref-R data values

D Diagnostics

Display only: List of unit prameters.

K Factory Calibration Settings

Display only: Cal. parameters, i.e. linearization
and temperature compensation coefficients.

R Factory Reset

Replaces user data with factory calibration data

Table 1. Diagnostics and Factory Settings

Analog out

Select 1 2 3 4

4-20mA out 1 Flow Flow Temp Temp
4-20mA out 2 Temp Flow Flow Temp

Pulse out

Select 1 2 3 4

Source out Pulse Pulse Alarm0 Alarm0

Set Factor Factor Set pt.0 Set pt.0
Set Period Period State0 State0
Set State0 State0

Units

Select E=English M=Metric
Select 0= SFPS 5 = SMPS
or 1 = SCFM 6 = NCMH
or 2 = SCFH 7 = NCMM
or 3 = LBS/H 8 = KG/H

or 4 = GPM 9 = LPM

For Volumetric or Mass Flow

Select R = Round pipe or duct
or S = Square duct
Set Diameter or Wide X High (in inches or mm)

Set CMaxflow = Maximum flow rate (span)
Set CMinflow = Minimum flow rate (zero)

Note: Changing units requires rescaling the unit (set new zero and span).

Table 2. “Z” Flow Units Set-Up and Scaling

Sink Pulse Alarm1 Pulse Alarm1

Table 3. “V” Output Configuration Set-Up

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Set Set pt.1 Factor Set pt.1
Set State1 State1 Period State1

State1

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“V” Menu Output Configuration Set Up

NOTE: The display comes up to the last setting saved and stays for 2 seconds. If N or [ENTER] is entered, the menu
proceeds to the Pulse out. If Y is entered, the display moves to the selection options and/or asks for confirmation. If you
miss the option, select [Enter] repeatedly to loop around.

Analog out

Output Mode
Selected

4-20mA #1: Flow
4-20mA #2: Temp

Change? (Y/N)>

4-20mA #1: Flow
4-20mA #2: Temp

Enter 1 to make

the selection__
4-20mA #1:
4-20mA #2: Flow

Enter 2 to make

the selection__
4-20mA #1: Temp
4-20mA #2: Flow

Enter 3 to make

the selection__
4-20mA #1: Temp
4-20mA #2: Temp

Enter 4 to make

the selection__

Pulse out

Pulse Out
Selected

Source: Pulse
Sink: Pulse

Change? (Y/N)>

Source: Pulse
Sink: Pulse

Source: Pulse
Sink: Alarm1

Source: Alarm0
Sink: Pulse

Source: Alarm0
Sink: Alarm1

Enter 1 to make
the selection #__

Enter 2 to make
the selection #__

Enter 3 to make
the selection #__

Enter 4 to make
the selection #__

PFactor: 1.000
Change? (Y/N)>

if yes

Enter new factor: ____

Sample Period: 1 second

Change? (Y/N)>

if yes

Enter new Sample Period: ____

If alarm is a selected output

Set point1: 000 Set points are in the

Change? (Y/N)>

if yes

Enter new set point: ____

Resume normal operation

Source state:
High to Low

Change to Low to High?>

Example: COMMAND V (Reference Table 3)

Case: 4-20mA #1 = flow, 4-20mA #2 = Temperature, Source Out = Pulse, Sink = Alarm

Pressing [V] [ENTER] will display “Output Mode Selected” followed by:

“4-20mA #1 = Flow” “ 4-20mA #2 = Temp” followed by
“Change? (Y/N)”
Press [ENTER] (no change).

The last saved mode will display at this point. i.e.,

“Source: Pulse” “Sink: Pulse” followed by,
“Change? (Y/N)” Select Y [Enter]. The display reads,
“Source: Pulse” “Sink: Pulse” followed by,
“Enter 1 to make the selction #.” Select [ENTER]. The next display reads,
“Source: Pulse” “Sink: Alarm” followed by,
“Enter 2 to make the selction #.” Select 2 and [ENTER]. The next prompt reads,
“PFactor: 1.000” “Change? (Y/N)>” (this factor can be anywhere from 0.001 to 1000 - A

pulse factor of 1.000 will output 1 pulse per unit of
flow.)

If no change, select N and/or [ENTER] to continue.

The next prompt is, “Sample Period”
“Change? (Y/N)>” (this value may be set from 0.5 to 5 seconds)

If no change, select N and/or [ENTER] to continue.

The next prompt is, “Source state: ” “High to Low” Change to “Low to High?>” (this selection toggles the pulse

signal normally high or normally
low).

[ENTER] to read display.
“Switchpt1” “0.0000000” the current set point.
“Change? (Y/N)>” enter Y [ENTER] and enter #______ . Set Point Value , i.e. 50 (value is in same units as the flow and

must be within the calibrated range). [ENTER]. The next prompt is,
“Sink state: ” “High to Low” Change to “Low to High?>”. Set the output signal to be normally “High” or

normally “Low.” Pressing [Y] [ENTER] toggles the current setting. Pressing [ENTER] resumes normal operation.

same units as the flow
or temp.

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PDA IR Communication Interface

The IR interface software is an optional accessory kit and can ordered using FCI part number 019819-01. The software is compatible
with PALM OS 4.1 or greater. If the software was ordered with the instrument, a CD should be located with the instrument documen­tation.

The factory has verified the following 3 PDA models. All commands meet their intended purpose and function properly.

1. Palm, Tungsten E, E2:Palm OS 5.2.1, 5.4.7

2. Palm, Zire 71, Palm OS 5.2.1

3. ecom instruments, m 515-EX, Intrinsically-safe. Palm OS 4.1

Procedure:

1. Down load the software into the target PDA. When complete, a yellow and blue FCI icon will be available.

2. Verify JP5 jumper is set in the PDA IR interface position, see Figure H.

3. Select FCI icon on PDA device.

4. The opening menu is displayed, select start.

5. Five menu groups are displayed.

Process: displays current process variables (Flow and Temperature)
ID-Unit: displays model, firmware version, serial no. …
Set-up: allows access to the following areas

Units K Factor
Line size Temp/Flow min/max
Totalizer Output Cal
LCD Output Config

Diagnostics: A/D values
Utilities: allows access to the following areas

Reset
Parameter memory
Calibration coefficients
Factory restore
Process and System Faults

6. After entering into specific menu areas, point the PDA IR port towards the Instrument display. Begin with the PDA device within
5 feet of the instrument display. Select the “Get All” or “Get” button to retrieve information from the instrument. If a value needs
to be changed, the value must first be retrieved.

Example: reading standard process variable information

1. Verify instrument and PDA are functioning.

2. Select FCI icon on the PDA.

3. Select the start button on the opening screen.

4. Select the “Process” button.

5. Point the PDA at the instrument display, start with the PDA no futher that 5 feet from the instrument.

6. Select the “Get Data” button.

7. Flow and temperature Data will begin streaming to the PDA.

8. If the IR link is interrupted, a “Command response timed out” message will be displayed.

9. Repeat the process if the link is interrupted.

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Maintenance

The FCI instrument requires little maintenance. There are no moving parts or mechanical parts subject to wear in the instrument. The
sensor assembly which is exposed to the process media is composed of 316 SS and Hastelloy C.

Without detailed knowledge of the environmental parameters of the application surroundings and process media, FCI cannot make
specific recommendations for periodic inspection, cleaning, or testing procedures. However, some suggested general guidelines for
maintenance steps are offered below. Use operating experience to establish the frequency of each type of maintenance.

Calibration

Periodically verify the calibration of the output and recalibrate if necessary. FCI recommends every 18 months at a minimum.

Electrical Connections

Periodically inspect cable connections on terminal strips and terminal blocks. Verify that terminal connections are tight and physically
sound with no sign of corrosion.

Remote Enclosure

Verify that the moisture barriers and seals protecting the electronics in the local enclosure is adequate and that no moisture is entering
the enclosure.

Electrical Wiring

FCI recommends occasional inspection of the system’s interconnecting cable, power wiring and flow element wiring on a “common
sense” basis related to the application environment. Periodically the conductors should be inspected for corrosion and the cable
insulation checked for signs of deterioration.

Flow Element Connections

Verify that all seals are performing properly and that there is no leakage of the process media. Check for deterioration of the gaskets
and environmental seals used.

Insertion Type Flow Element Assembly

Periodically remove the flow element for inspection based on historical evidence of debris, foreign matter, or scale build-up and
appropriate plant shutdown schedules and procedures. Check for corrosion, stress cracking, and/or build-up of oxides, salts, or foreign
substances. The thermowells must be free of excessive contaminants and be physically intact. Any debris or residue build-up could
cause inaccurate flow indication. Clean the flow element, as necessary, with a soft brush and available solvents (compatible with
Stainless Steel).

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Troubleshooting

Application Verification

After verifying that the flow meter is functioning, review the application parameters as shown below to verify the calibration matches
the process media.

Equipment Needed

Flow Instrument Calibration Data
Process Parameters and Limits

Check Serial Numbers

Verify that the serial number of the flow element and the flow transmitter electronics are the same. The flow element and the flow
transmitter are a matched set and cannot be operated independently of each other.

Check the Instrument Installation

Verify correct mechanical and electrical installation. Verify the flow element is mounted at least 20 diameters downstream and 10
diameters upstream from any bends or interference in the process pipe or duct.

Check for Moisture

Check for moisture on the flow transmitter. Moisture may cause intermittent operation. Check for moisture on the flow element. If a
component of the process media is near its saturation temperature it may condense on the flow element. Place the flow element where
the process media is well above the saturation temperature of any of the process gases.

Check Application Design Requirements

Application design problems may occur with first time application instruments, although the design should also be checked on
instruments that have been in operation for some time. If the application design does not match field conditions, errors occur.

1. Review the application design with plant operation personnel and plant engineers.

2. Ensure that plant equipment such as pressure and temperature instruments conform to the actual conditions.

3. Verify operating temperature, operating pressure, line size, and gas medium.

Verify Standard Versus Actual Process Conditions

The flowmeter measures the mass flow rate. The mass flow rate is the mass of the gas flowing through a pipe per time. Other flow
meters, such as an orifice plate or a pitot tube, measure the volumetric flow rate. The volumetric flow rate is the volume of gas per
time. If the readings displayed do not agree with another instrument, some calculations may be necessary before comparing them. To
calculate the mass flow rate, the volumetric flow rate, and the pressure and temperature, the point of measurement must be known. Use
the following equation to calculate the mass flow rate (Standard Volumetric Flow rate) for the other instrument:

Equation:

QQ

=× ×

SA

Where: used for pressure and temperature.)
QA= Volumetric Flow QS= Standard Volumetric Flow
PA= Actual Pressure TA= Actual Temperature
PS= Standard Pressure TS=
PSIA and °R are used for pressure and temperature units.

P

T

A

A

T

S

P

S

Standard Temperature

(Metric: Where bar(a) and °K are

Example: (Metric: PS = 1.01325 bar(a)

QA= 1212.7 ACFM QS= 1485 SCFM TS = 21.1°C (294.1K))
PA= 19.7 PSIA TA= 120°F (580°R)
PS= 14.7 PSIA TS= 70°F (530°R)

1212.7 ACFM

(

This page is subject to proprietary rights statement on last page

1

)

(

19.7 PSIA
580° R

12 Doc. No. 06EN003368 Rev. C

)

(

530° R_

14.7 PSIA

)

=1485 SCFM