Omega FHG Series User manual

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FHG FLOW METERS
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User’s Guide

Servicing North America:
U.S.A.: Omega Engineering, Inc., One Omega Drive, P.O. Box 4047
ISO 9001 Certified Stamford, CT 06907-0047 USA
Toll Free: 1-800-826-6342 TEL: [phone]
FAX: [phone] e-mail: [email protected]
Canada: 976 Bergar
Laval (Quebec), Canada H7L 5A1
Toll-Free: 1-800-826-6342 TEL: [phone]
FAX: [phone] e-mail: [email protected]
For immediate technical or application assistance:
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Customer Service: 1-800-622-2378/1-800-622-BEST®
Engineering Service: 1-800-872-9436/1-800-USA-WHEN®
Mexico: En Español: 001 [phone] FAX: [phone]
[email protected] e-mail: [email protected]
Servicing Europe:
Benelux: Managed by the United Kingdom Office
Toll-Free: 0800 099 3344 TEL: [phone]
FAX: [phone] e-mail: [email protected]
Czech Republic: Frystatska 184
733 01 Karviná, Czech Republic
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Toll-Free: 0800 466 342 TEL: [phone]
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FAX: [phone] e-mail: [email protected]
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Toll-Free: 0800-488-488 TEL: [phone]
FAX: [phone] e-mail: [email protected]
OMEGAnet®Online Service Internet e-mail
omega.com [email protected]
It is the policy of OMEGA Engineering, Inc. to comply with all worldwide safety and EMC/EMI
regulations that apply. OMEGA is constantly pursuing certification of its products to the European New
Approach Directives. OMEGA will add the CE mark to every appropriate device upon certification.
The information contained in this document is believed to be correct, but OMEGA accepts no liability for any
errors it contains, and reserves the right to alter specifications without notice.
WARNING: These products are not designed for use in, and should not be used for, human applications.

OPERATING INSTRUCTIONS
For FHG Series Flow Meters

2
Table of Contents
Page
Important Basic Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1. Function Description of the FHG Flow Meters ....................................3
2. General Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. FHG Flow Meter Selection ...................................................4
4. Declaration of Conformity....................................................4
5. General Operating Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
6. Maximum Operating Pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
7. Information about the EU Pressure Equipment Directive 97/23/EC ...................5
8. Flow Rate Measuring Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
9. Mounting the Flow Meter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
10. Cleaning and Flushing of Pipeline before Initial Start-Up ..........................6
11. Fluid Filtering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
12. Sensor Electronics Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
13. Pulse Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
14. Programming the Preamplier Electronics .....................................11
15. Signaling LEDs ...........................................................12
16. Operating Mode Messages ................................................12
17. Alarm and Warning Messages ..............................................13
18. Preamplier Technical Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
19. Preamplier Pin Assignment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
20. Maintenance ............................................................14
21. Returning for Repairs and Sample Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
22. FHG Flow Meter Technical Data ............................................15
23. FHG Flow Meter Flow Characteristics ........................................16
24. FHG Flow Meter Dimensions ...............................................17
25. Pin Assignment ...........................................................18
26. Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
The current publication of this operating instruction supersedes all information from previous
publications. Omega reserves the right to make changes and substitutions. Omega is not liable
for any printing errors. Reproduction, including excerpts, is permitted only after written appro-
val by Omega. Omega reserves the right to modify technical data at any time. Last revised:
12/2012

3
FHG ow meters measure the ow rate based on the screw pump principle.
A pair of rotors tted precisely into the housing constitutes the measuring
element. An integrated gear and non-contact signal pick-up system detects
the rotations of the measuring element and converts them to digital pulses.
Together with the housing walls, the rotor edges form closed measuring
chambers in which the uid is transported from the inlet to the outlet side.
The uid volume put through within one main rotor rotation is the rotation
volume, which is divided by the sensing gear and digitised, processed and
output in the sensor module.
Advantages
• High degree of precision that is mostly independent of viscosity
• Pulsation-free measurement
• Lowest pressure losses
• Short response time due to innovative rotor prole and
• Highest functionality due to intelligent sensor technology
• Gentle uid measurements
Sensor System Explanation
The non-contact pick-up system consists of two GMR bridges (sin /cos), which
are located in a sensor unit in cartridge design. It detects the movement of
the sensing gear and routes the sin/cos signals to the preamplier electronics.
The preamplier electronics digitise and amplify the sensor signals and mul-
tiply them by a high-resolution interpolator using adjustable settings. The
square wave signals are bidirectional and can be utilised by any evaluating
instrument as well as computers and PLC controls.
The resolution is selectable in steps from factor 1 to 128.
In case of a 1-channel evaluation, a separate directional signal is available.
An adjustable pulse lter can offset and suppress negative ows (e.g. gene-
rated by vibrations) while still in the device.
The frequency of the output signals is proportional to the ow (volume ow)
and depends on the respective ow meter size. The frequency range is from
0 to 100 kHz. The preamplier is protected against reverse polarity and
incorrect connection. It is designed for media temperatures of -30°C to
+120°C and is mounted directly on the FHG ow meter.
1. Function Description of the FHG Flow Meters
Important basic information
These installation and operating instructions should provide you with the information you need to properly install and commission
the ow meter. Installation, commissioning and testing are to be performed by trained and qualied personnel only. These operating
instructions must be read and applied carefully to ensure proper, trouble-free and safe operation of the ow meter. Omega is not
liable for any damage incurred resulting from not complying with the instructions in this operating instruction. It is not permitted in
any case to open the device.

4
2. General Description
Please follow all instructions in this manual to ensure the trouble-free ope-
ration of the FHG ow meters. Omega does not assume responsibility or
liability for damages resulting from noncompliance with these instructions.
The device may only be opened within the warranty period after consulta-
tion and approval by Omega.
3. FHG Flow Meter Selection
4. Declaration of Conformity
5. General Operating Requirements
For the trouble-free, safe, and reliable operation of the ow meters, se-
lecting the correct type and size is critical. Because of the wide variety of
applications and ow meter designs, the technical data in the Omega cata-
log are general in nature. Certain properties of the devices are dependent
on type, size and measuring range, as well as the liquid to be measured.
Please contact Omega or one of our sales and service representatives for
detailed information about the appropriate ow meter for your particular
application.
Flow meters of the ”FHG“ series have been tested for their electromagnetic
compatibility and interference emissions as outlined by the EMC Directive
and are in compliance with the applicable statutory EMC Directives.
They cannot be operated independently, are connected by cable to a po-
wer source, and provide digital electrical signals for electronic evaluation.
All ow meters have a declaration of conformity, which can be requested
if necessary.
Since the electromagnetic compatibility of the entire measuring sys-
tem is also dependent on the installation of the cables, the correct
connection of the shield, and each individual connected device, all
components must comply with the EMC Directive, and the electroma-
gnetic compatibility of the entire system, machine, or system must be
ensured as well.
All ow meters have been tested in accordance with the applicable statuto-
ry EMC Directives of EN 61000-6 and are CE certied. The EC conformity
marking is the CE mark afxed to all ow meters.
Before assembly, commissioning or operation, check and verify the following
properties & aspects of the respective circumstances of your system to ensure
operation is trouble-free, safe, and reliable.
1. The Fluid to be Processed
Are the flow meter seals and materials compatible with for the fluid and any cleaning agents that will be used?
 Is the uid viscous or abrasive? Have you properly sized the meter and selected appropriate bearing materials?
 Is the uid dirty or does it contain contaminants/pollutants and solid particles that may require ltration?
 Does the uid have llers or other additives? What grain sizes do these solids have, and could they block the measuring element?
 Is it necessary to install an upstream hydraulic lter (see ltering requirements in section 22 of this document)?
 Are tubes and pipes clean and free of assembly residues such as chips, weld spatter?
 Is the tank clean and is it impossible for impurities or foreign substances to reach the pipeline or tubing system from the tank?
 Is a different uid used frequently and is the system sufciently ushed and rinsed in between?
 Are pipelines/tubes and the entire system completely deaerated (the system should be slowly lled with uid before operation at full ow
to avoid hydraulic shock on the mechanical components)?
2. Hydraulic Properties of the System
 Is the max. operating pressure of the system less than the max. permissible operating pressure of the ow meter?
 Is the max. pressure drop ∆p (at ow meter) below the max. permissible pressure drop?
 Is the pressure drop ∆p not excessive with max. ow (e.g. high viscosity)?
 Does the ow range of the ow meter (dependent on the viscosity) correspond with the present ow?
 Please note that the ow range is less with higher viscosity!
 Does the temperature range of the ow meter correspond with the present max. temperature of the uid?
 Is the cross-section of the pipelines/tubes large enough and are there no overly large pressure drops in the system?
 Is the hydraulic connection (inlet/outlet) connected corrected and sealed properly?
 Note: A blocked ow meter can stop the entire ow. Does the system feature an overpressure / bypass valve? This valve must be checked and
maintained at regular intervals.

5
3. Electronic Evaluation and Electrical Safety
Does the supply voltage of the ow meter match the available power supply?
 Is the supply voltage to the power supply adapter or the evaluating device sufciently ltered?
 Does the output of the supply voltage correspond with the required output?
 Is the electrical connection established based on the enclosed wiring plan (see page 19)?
 Is the cable shield correctly grounded on both sides to a clean common ground (PE)?
 Is there a potential difference between the ground on the ow meter and at the evaluating device?
 Is the ow meter permanently grounded (PE) (e.g. via the pipelines)?
 If the measuring element of the flow meter is insulated from ground (PE), the meter must be grounded with a cable!!
 Is the 4-pin to 5-pin round pin plug of the connection cable rmly attached to the plug of the ow meter?
 Are the wires at the evaluating device connected correctly?
 Does the entire system meet the legal rules and regulations concerning electromagnetic compatibility (EMC)?
 Is compliance with all local rule and regulations, applicable rules, guidelines and basic conditions of the EMC ensured?
 Systems where a malfunction or failure may lead to personal injuries must be equipped with suitablesafetymechanisms. The function of these
safety mechanisms must be checked at regular intervals.
6. Maximum Operating Pressure
Before installing the ow meter, you must check whether the max. operating
pressure of the system does not exceed the max. permissible operating
pressure of 450 bar of the ow meter. Make sure to keep in mind that peak
pressures may occur when operating the system.
Important:
Please contact Omega with all operating pressures > 450 bar and in case of special models.
7. Information about the EU Pressure Equipment Directive 97/23/EC
Omega ow meters of the ”FHG“ series qualify as “pressure equipment“ as
dened by Section 1, Paragraph 2.1.4. of the directive listed above and as
such are affected by the regulations of this directive.
Omega ow meters must therefore meet the technical requirements speci-
ed in Section 3, Paragraph 1.4 of the directive. The uids to be measured
are for the most part Group 2 uids acc. to Section 9, Paragraph 2.2.
Omega ow meters do not reach the limit values specied by Section 3,
Paragraph 1.1. The technical requirements for Omega ow meters are
therefore conned to the criteria specied in Section 3, Paragraph 3. This
means that the devices must be designed and manufactured in accordance
with the provisions of good engineering practice applicable in a member
state. This is hereby conrmed. The section also stipulates that such pres-
sure equipment and components or accessories are not allowed to bear
the CE marking in accordance with the Pressure Equipment Directive. This
means that a declaration of conformity is not issued for Omega ow meters
and the devices are not provided with the CE mark as pertaining to Direc-
tive 97/23/EC.
Important:
Verify that the specied maximum permissible operating pressure of the ow meter
can never be exceeded in any operating mode of the system. Also pay attention to the
ow measuring range, which is dependent on the viscosity of the uid to be measured.
8. Flow Rate Measuring Range
The ow rate measuring range specied in the data sheet (Qmin – Qmax)
of the ow meter refers to the test uid ‚hydraulic oil‘ with a viscosity of
21 mm2/s at a temperature of 20°C. For this measuring range, Omega
species accuracy up to 0.3% of the measured value and a repeatability
of 0.05%.
In uids with low viscosity (< 21 mm²/s), the measurement accuracy de-
grades while it may improve with uid with a high viscosity (> 21 mm²/s).
Note also that the ow measuring range is limited at higher viscosity (see
data sheet of the ow meter). The characteristic pressure loss curves are
listed in Section 23.

6
9. Mounting the Flow Meter
The ow meter should be mounted in an easily accessible location so that
disassembly to clean the measuring elements is easy. Since ow meters
operate in any installation position and ow direction, you can mount it
anywhere in your system. When installing the ow meter, make sure that
liquid remains in the ow meter even at standstill of the system and that the
ow meter can never run dry. The outlet of the ow meter should always
have a certain backpressure since this xes the measuring element of the
ow meter in the liquid column (the measuring element uses to support itself
on the liquid column) and the pipeline cannot empty itself. In critical cases,
or if the pipeline can run empty in standstill or standby mode, it is always
advisable to install an additional non-return check valve in the outlet line.
Flow meters of the ”FHG“ series can be installed in the pipeline. Always
select large cross-sections (if possible) for the hydraulic inlet and outlet or
the entire pipeline system. This reduces the pressure drop and the ow rate
throughout the system.
Installation Notes
Installation Position
Any, note arrow indicating preferred direction if necessary (calibration ar-
row).Mount the device in such a way that the preamplier is turned away
from any potential heat source.
Straight pipe sections are not required in inlet/outlet.
Connecting Units
If the connecting units (mounting anges) are to be installed on-site, compli-
ance with the specied torque is required.
Important:
Make sure that the ow meter measuring elements are always completely lled both
in inow and outow and that the outow has a little backpressure. This prevents the
measuring elements from being damaged by a sudden and steep increase of ow and
at the same time improves measurement accuracy.
Fig. 1: Flow meter with backpressure
Pipe Thread
Please comply with the screw-in depths and sealing systems. PTFE tape or
liquid sealants such as adhesives are not permitted!
Fastening
The devices must be installed stress-free into the pipeline. This is accomplis-
hed with fastening screws located at the face sides in the connecting units.
For stress-free assembly, the compressive strength may be limited!
FHG Flow Meter Size Torque
FHG 1x x2 70 Nm
FHG 1x x4 120 Nm
FHG 1x x5 240 Nm
FHG 1x x7 160 Nm
Table 1: Starting torque of the connection units
10. Cleaning and Flushing of Pipeline before Initial Start-Up
Before initial start-up of the ow meter, you must ush and clean the whole
system to prevent contaminants from reaching the measuring elements duri-
ng the assembly and installation. Foreign matter or contaminants may block
the ow meter or severely damage it so that the ow meter readings are no
longer valid and the device must be returned for repairs. After completion
of the installation or piping, you must rst ush the entire pipeline system
and carefully clean and ush the tank. This requires that the ow sensor is
removed from the uid circuit to ush out all foreign matter or contaminants
(e.g. chips, metal parts) without problems. Use a rinsing uid that is compa-
tible with the subsequent used uid and will not cause adverse reactions.
Such information can be obtained from the supplier or manufacturer of the
uid or from Omega.
Flow meters are sensors manufactured with a high degree of precision.
They have mechanical measuring elements consisting of two rotors tted
into the housing with narrow gaps. Even the smallest damage to the rotors
causes a measuring error. Always make sure that foreign matter or conta-
minants cannot reach the measuring elements and that the uid owing
through the ow meter is always free of pollutants and particles. Once the
system is thoroughly ushed and no extraneous material is in the piping sys-
tem, you can mount the ow meter into the uid circuit and start the actual
initial startup process.
Non return valve
Flow meter
Tank

7
11. Fluid Filtering
Heavily contaminated uids or foreign matter in the uid can block, da-
mage, and even destroy the ow meter. In these cases, always install a
sufciently large lter in front of the ow meter so that foreign particles and
solids are prevented from entering the measuring elements, thus preventing
damage to the ow meter. The required ltering depends on the size, bea-
ring, and design of the ow meter.
Flow meter size Filter size for
ball bearing
FHG 1x x2 250 µm
FHG 1x x4 250 µm
FHG 1x x5 500 µm
FHG 1x x7 500 µm
Table 2: Upstream lters
The lter size for ow meters with slide bearings, in special designs, or with
specially adapted measuring element tolerances can be obtained from
Omega upon request.
Important:
A blocked ow meter is capable of stopping the entire ow.
An overpressure / bypass valve must be installed in the system side.
12. Sensor Electronics Function
The liquid to be measured ows through the rotor chambers in axial direc-
tion, resulting in an even rotation of the screw spindles.
This is done especially gentle and with very low resistance for the uid to
be measured as well as pulsation-free and almost free of leaks due to the
specially designed uidic prole geometry.
A magnet wheel permanently afxed to the rotors is scanned without
contact with a sensor module. The non-contact pick-up system consists of
two GMR bridges (sin/cos), which are located in a sensor unit in cartridge
design. It detects every movement of the sensing gear and routes the sin/
cos signals to the preamplier electronics. The preamplier electronics di-
gitise and amplify the sensor signals and multiply them by a high-resolution
interpolator using adjustable settings. The square wave signals phase-shif-
ted by 90° are bidirectional and can be utilised by any evaluating device
as well as computers and PLC controls.
The ow is proportional to the edges/pulse count and the ow rate is pro-
portional to the frequency. The adjustable interpolator can be used to ad-
just the resolution explicitly to the downstream connected evaluating unit
for obtaining highly precise measuring results of the entire system. This ap-
plies to the following application cases, for example:
• Measuring, controlling, and regulating high viscosity uids
• Measuring, controlling, and regulating in lower ow ranges
• Measuring, controlling, and regulating when passing through zero
• Measuring, controlling, and regulating in both ow directions
• Measuring, controlling, metering, and lling of small volumes
The resolution is selectable in steps from factor 1 to 128. The frequency
range is from 0 to 100 kHz.
In case of a 1-channel evaluation, a separate directional signal is availa-
ble.
The preamplier is protected against reverse polarity and incorrect con-
nection. It is designed for uid temperatures of -30°C up to +120°C and is
mounted directly on the FHG ow meter.
The uid volume passed through by one gear division of the sensing
wheel within the measuring element is divided by the set interpolation fac-
tor.
This forms the measurement volume per pulse (Vm) with the dened unit
[cm³/puls e].
The frequency of the output signals can be calculated as follows:
Formula 1: Calculation of the output frequency with Q in l/min
Table 2, Formula 2, and the subsequent diagrams can be used to determine
the corresponding resolution or the corresponding IPF for the respective
application.
Adjustable interpolation factors IPF: 1, 2, 5, 10, 25, 32, 50, 64, 100, 128
f= Q x1000
Vm60

8
FHG 100
Interpolation
factor (IPF)
Switch
position
S3
Measurement
volume Vm
[cm3/Imp]
K-Factor
[Imp/l]
K-Factor
[Imp/
gal.]
1 0 0,5815 1720 6510
2 1 0,29075 3439 13020
5 2 0,11630 8598 32549
10 30,05815 17197 65098
25 40,02326 42992 16274 5
32 50,01817 55036 208335
50 60 , 0116 3 85985 325489
64 70,00909 110 011 416440
100 80,00582 171821 650419
128 90,00454 220264 833797
FHG 400
Interpolation
factor (IPF)
Switch
position
S3
Measurement
volume Vm
[cm3/Imp]
K-Factor
[Imp/l]
K-Factor
[Imp/
gal.]
1 0 3,138 319 1206
2 1 1,569 637 2413
5 2 0,6276 1593 6032
10 30,3138 3187 12063
25 40,12552 7967 30158
32 50,09806 10198 38603
50 60,06276 15934 60316
64 70,04903 20396 77207
100 80,03138 31867 120632
128 90,02452 40783 154382
FHG 800
Interpolation
factor (IPF)
Switch
position
S3
Measurement
volume Vm
[cm3/Imp]
K-Factor
[Imp/l]
K-Factor
[Imp/
gal.]
1 0 10,00000 100 379
2 1 5,00000 200 757
5 2 2,00000 500 1893
10 31,00000 1000 3785
25 40,40000 2500 9464
32 50,31200 3200 12113
50 60,20000 5000 18927
64 70,15625 6400 24227
100 80,10000 10000 37854
128 90,07813 12799 48451
FHG 2500
Interpolation
factor (IPF)
Switch
position
S3
Measurement
volume Vm
[cm3/Imp]
K-Factor
[Imp/l]
K-Factor
[Imp/
gal.]
1 0 37,00000 27 102
2 1 18,50000 54 204
5 2 7,40000 135 511
10 33,70000 270 1022
25 41,48000 675 2555
32 51,15625 864 3270
50 60,74000 1350 5110
64 70,57813 1728 6540
100 80,37000 2700 10220
128 90,28906 3456 13081
Table 3: Measurement volumes and K-factors
Formula 2: Calculating the max. IPF
The set IPF may not be larger than the calculated IPF!
IPF Interpolation factor
fmax Max. processable input frequency
VmIPF1 Measurement volume with IPF = 1 (volume of a gear structure of the sensing wheel)
Qmax Max. operating ow in l/min
IPF ≈ fmax x VmIPF1 x 60
Qmax x 1000

9
FHG 1xx2
FLOW vs FREQUENCY
FHG 1xx4
FLOW vs FREQUENCY
Flow diagrams vs frequency

10
FHG 1xx5
FLOW vs FREQUENCY
FLOW vs FREQUENCY
FHG 1xx7
Example
Flow meter: FHG 1xx4
Max processable input frequency of the downstream evaluating unit: 20 kHz
Max. operating ow: 140 l/min
Path 1: The diagram yields an IPf of 25
Path 2:
IPF ≈fmax x VmIPF1 x 60
Qmax x 1000 =20.000 x 3,138 ml x60 s =26,9 ≈25 140 1000 ml
1
s

11
13. Pulse Filtering
Oscillations in uid systems manifest themselves through constant forward
and backward movements of the liquid column, which is also detected by the
rotor sensors and converted into proportional electronic pulses or edge se-
quences. Depending on the application, oscillations or vibrations can occur
during the ow rest phases or discontinuous ows. The pulses generated du-
ring the osciallation phase can be incorrectly interpreted by the downstream
evaluating unit or controller, which can be very distracting for the respective
operating process.
The signal ltering function of the internal electronics continuously offsets
these generated edges during the rapid forward and backward movements
of the rotor measuring unit. The signals at the channel outputs are also sup-
pressed at the same time until the internal offset is equalized or the initial
position of the rotor measuring unit has been reached again (see Fig. 3).
The user is able to set the degree of ltering in the form of partial volumes
using rotary coding switches.
Adjustable pulse ltering: 0Z, 0.25Z, 0.5Z, 0.75Z, 1.0Z, 1.25Z, 1.5Z, 1.75Z,
2.0Z, 2.25Z, 2.5Z, 2.75, 3.0Z, 3.25Z, 3.5Z, 3.75Z (Z: gear unit)
Fig. 3: Pulse ltering principle
Filter
position
FHG 1xx2 FHG 1xx4 FHG 1xx5 FHG 1xx7
0 0 0 0 0
10.145375 0.7845 2.5 9.25
20.29075 1.569 5.0 18.50
30. 436120 2.3535 7. 5 27. 75
40.5815 3.138 10.0 37. 0 0
50.726875 3.9225 12.5 46.25
60.87225 4.707 15.0 55.5
71.017625 5.4915 17. 5 64.75
81.163 6.276 20.0 74.0 0
91.308375 7.0605 22.5 83.25
10 (A) 1.45375 7. 8 4 5 25.0 92.50
11 (B ) 1.599120 8.6295 27. 5 101.75
12 (C) 1.74 4 5 9.414 30.0 111. 0 0
13 (D) 1.889875 10.1985 32.5 120.25
14 (E) 2.03525 10.983 35.0 129.50
15 (F) 2.180625 11. 7675 37. 5 138.75
148
Table 4: Suppressed volume with pulse ltering activation
[ml]
14. Programming the Preamplier Electronics
The electronics elements are quickly and easily set. There are two rotary
coding switches on the electronics (S3, S4), a jumper (B2), a switch (S2)
and a key (S2). With the rotary coding switches, the IPF and the degree of
ltering are programmed.
Fig. 4: Preamplier electronics
B2
S1
S2
S4
S3

12
During initial startup, the switch S2 must rst be set to the corresponding
preferred direction of the ow. The positive ow direction of the FHG ow
meter system is specied in the top view of the 5-pin M12 connector. In this
case, the switch S1 must be set to ON. For the opposite negative direction,
the switch position is to be down and thus set to OFF. This setting ensures
that the pulse ltering is activated in the right direction from the very begin-
ning after switching on the supply voltage.
Pin 5 of the M12 connector is either used for the separate direction signal
or an error signal. This is set accordingly with the bridge B2. The gure
above depicts the bridge attached to the middle and right pin of the 3-pin
row of pins, which routes the separate zero signal to the third output. If the
bridge is on the left and middle pin, the error signal in case of a fault is
output. A description of the error states is found in the ”Alarm and Warning
Messages“ chapter.
Ten different interpolation factors can be set with the coding switch S3. The
corresponding interpolation factors for the respective switch positions are
listed in Table 3. This setting can be changed at any time while the system
is running. Simply use a small screwdriver to adjust the rotary coding switch
and then briey press the S2 key for the acknowledgment. The new pulse
rate is enabled a once.
The rotary coding switch for the pulse ltering has 16 switch settings. The
degree of ltering is determined with quarter gear division increments. The
corresponding suppressed partial volumes of the respective size are listed
in Table 4. Changes can also be performed during operation and become
active after pressing the S2 key.
The electronics is sensitive to electrostatic discharges. People making
adjustments to the electronics must rst discharge their electrostatic charges
using a grounded object.
Important:
People making adjustments to the electronics must rst discharge their electrostatic
charges using a grounded object.
15. Signaling LEDs
The signaling LEDs provide information about the corresponding status of the
electronics. These include certain operating and fault states (see Figure 5).
The three LEDs have a different combination of states for each signal. The
LEDs signal either operating modes or alarms and warnings. Operating
mode messages signal the respective mode that has been set.
Alarm and warning signals provide explicit information about overload,
conditions that can negatively affect the measurement, or component er-
rors of the measuring system.
Fig. 5: Signaling LEDs of the preamplier electronics
16. Operating Mode Messages
Mode Yellow
LED
Green
LED
Red
LED
Error output
Normal operation off on off off
Offset mode off Flashes off off
Table 5: Operating mode messages
GreenYellow Red

13
Warning Yellow
LED
Green
LED
Red
LED
Error output
Offset adjustment
necessary 1
Flashes on off off
Alarm Yellow
LED
Green
LED
Red
LED
Error output
Interpolator electronics
errors 2
Flashes off Flashes Pulse
Error at pick-up 3off on / off on on
Flow overload on off on on
max. frequency range
exceeded
(>100 kHz) 4
on on Flashes Pulse
Fluid temperature
> 120°C 5
Flashes on Flashes Pulse
Table 6: Alarm and warning messages
17. Alarm and Warning Messages
The electronics of the FHG ow meters can detect ve events that could
lead to measurement errors. In case of serious errors, the third output has
a ”high“ signal or a ”pulse“ signal if activated with the bridge B1. The
different error causes can be determined with the states of the three LEDs.
The red LED is linked with the error output. Each active state of this LED or
the error output signals an event that has negative effects on the measure-
ments.
Description of the Error Messages
1. Offset adjustment necessary: The sensor and/or the preamplier elec-
tronics were replaced. A different size was set.
2. Electronics errors: Defective component in interpolator circuit, unable to
determine internal conguration values
3. Pick-up errors: The sensor is defective or quit working. The distance bet-
ween the sensor and the magnet wheel has changed = mechanical
damage
4. Overload: The maximum permissible ow range was exceeded
5. Frequency errors: The max. output frequency of 100,000 Hz was excee-
ded. The IPF is dimensioned too high for the respective ow
6. Temperature errors: The temperature of the uid is too high (> 120°C)
and may result in awed or incorrect measurements
18. Preamplier Technical Data
Scanning sensor 2 x GMR sensors in a bridge circuit (sin/cos)
Adjustment automatic offset adjustment
Resolution programmable 1, 2, 5, 10, 25, 32, 50, 64, 100, 128
Adjustable pulse ltering 0Z, 0.25Z, 0.5Z, 0.75Z, 1.0Z, 1.25Z, 1.5Z, 1.75Z, 2.0Z, 2.25Z, 2.5Z, 2.75, 3.0Z, 3.25Z, 3.5Z, 3.75Z (Z: gear unit)
Frequency up to 100 kHz
Output signals Channel A, channel B, directional signal DIREC (high: positive, low: negative) or error signal ERROR
(high or pulse: error)
Channel A and B two signal outputs for outputting the digital ow sensor signals, a channel offset of 90° between channel A and
channel B;
Flow direction Detection of ow direction from the channel offset of the signals from channel A to channel B or via the separate direc-
tional signal.
Outputs Three current-limited and short-circuit-proof power ampliers (channel A, channel B, DIREC /ERROR); integrated
adjustment to a characteristic impedance of 75 Ω; driver current approx. 300 mA at supply of 24 V; small saturation
voltage of up to 30 mA load current, short switching times, integrated freewheeling diodes against Vband GND, ther-
mal shutdown with hysteresis; in case of error, the outputs are high impedance;
The 24 V line drivers are designed for control applications with cable adjustment
Error messages Electronics fault (e.g. faulty interpolator), sensor errors (e.g. sensor failure), offset adjustment necessary, overload (ow
peaks), frequency error (> 100 kHz), temperature error (> 120°C)
Operating voltage Vb= 10 … 28 VDC
Current consumption lnoload = approx. 40 mA, total current consumption depends on output load

14
Figure 6: Flange plug of the preamplier housing
19. Preamplier Technical Data
Fig. 6 depicts the pin assignment of the preamplier. This plug has ve pins.
Two pins are for the power supply (pin 1 and 3), two for the signal output
of channel 1, 2 (pins 2 and 4) and a separate output for error or direction
detection (pin 5).
However, please note that the cable shield at the plug side is on the metal
housing of the plug. The connection cable shield must be applied on both
sides. The shield is used to connect the PE from the evaluation electronics to
the preamplier housing and the measuring element of the ow meter. The
cable shield should always be continuous to the ow meter and not sepa-
rated by distribution boxes or junction boxes. Route the connection cable
as directly as possible from the evaluating device to the ow meter since
interruptions are always potential sources of error. The measuring elements
of the ow meter must be connected electrically with the protective earth
conductor (PE). This is generally ensured with the grounded pipelines.
If potential differences exist between the preamplier housing and
the protective conductor (PE) of the evaluating device, you must pro-
vide equalization.
Important:
Use only well shielded connection cables with a wire cross-section of ≥ 4 to 5 x 0.25 mm². Please note
that the housing of the round pin plug is metallic, has a connection for the
shield and that the potential of the PE is connected to the cable shield and the housing
of the preamplier.
Important:
Please make sure that no additional inductors such as contactors, relays, valves, etc. are
connected to the power supply of the ow meter. These components are potential sources
of interference (especially if the inductors are not provided with adequate protective circuits), produce
high interference pulses during the switching, and may disrupt the function
of the ow meter even though it complies with the EMC directives.
Pin 2
Digital signal
Channel 1
Pin 1
Power supply
Vb= 10-28 VDC
Pin 4
Digital signal
Channel 2
Metal housing connected with
shield and protective earthing
conductor PE
Pin 5
Digital signal
ERROR/DIREC
Pin 3
Power supply
GND (-Vb= 0 V)
Plug top view
Depending on the operating conditions, the service life and thus the specic characteristics
of the equipment are limited due to wear, corrosion, deposits, or aging. The operator is responsible for
carrying out periodic inspections, maintenance, and re-calibrations. Each observation of a malfunction
or damage makes it necessary to stop operation. We can loan a device for the duration of the overhaul
if requested. We recommend an annual inspection and recalibration.
20. Maintenance

15
21. Returning for Repairs and Sample Devices
22. FHG Flow Meter Technical Data
Repairs on the ow meter and other components can be carried out quickly
and efciently only if you include detailed information about the claim or
defect when returning the device. In addition, a safety sheet must be enc-
losed, clearly indicating what uid has been used with the ow meter and
how hazardous this uid is.
Compliance with the laws on occupational safety, such as Workplace Re-
gulations (ArbStättV), Accident Prevention Regulations and Regulations on
Environmental Protection, Waste Law (AbfG) and Water Act (WHG), re-
quire that businesses protect their employees and other people as well as
the environment from harmful effects when handling hazardous substances.
If additional precautions are required despite careful draining and clea-
ning of the ow meter, the associated required information must be inclu-
ded when returning the device. Please note that inspection and repair is
only performed on ow meters returned to Omega if the safety sheet of the
used uid is enclosed and if the ow meter has been completely cleaned
and ushed. This is to protect our employees and makes our work easier.
In case of noncompliance with this rule, the devices are returned to
the sender without attaching postage to the package.
Overall size Measuring range
(Qmax.) l/min.
RV
ccm/rev.
VE
ccm/Imp.
K – Factor
Imp./l min.
K – Factor
Imp./l max.
P max.
bar
Filtering
µm
FHG 1x x2 0.50 – 100 (120) 15.7 0.5815 1,720 220,000 450 250
FHG 1x x4 1.00 – 400 (525) 56.5 3.138 318 40,800 450 250
FHG 1x x5 4.00 – 800 (1,000) 180.0 10 100 12,800 450 500
FHG 1x x7 10.00 – 2,500 (3,000) 666.0 37 27 3,459 40 500
Frequency range 0 … 100 kHz, adjustable
Measuring accuracy ± 0.3% [0.5%]*, [1%]** of measured value at viscosity of 21 cSt
*FHG 1xx5, **FHG 1xx7
Repeatability ± 0.05% with same operating conditions
Materials
Gray cast iron version EN-GJS – 400 – 15 (EN 1563) / 100 Cr 6
Stainless steel version Stainless steel 1.4305/1.4112, additional available upon request
Bearing Fluid-dependent as anti-friction bearing or SSIC/wolfram carbide friction bearing
Seals FPM (standard) PTFE, NBR, EPDM upon request
Fluid temperature -30°C ... +120°C
Viscosity range 1 … 1,000,000 cSt
Installation position Any using selectable connection units, also customer specic
Supply voltage 9 … 28 VDC
Current consumption 65 mA at 24 VDC unloaded
Delay time ≤ 8 mµs
Protection type IP 65

Baugröße 100
Durchussbereich 0 bis 120 l/min
Baugröße 400
Durchussbereich 0 bis 500 l/min
Baugröße 800
Durchussbereich 0 bis 1.000 l/min
Baugröße 100
Durchussbereich 0 bis 10 l/min
Durchuss Q Durchuss Q
Durchusswiderstand ∆p
Durchuss Q
Durchusswiderstand ∆p
Durchuss Q
Durchusswiderstand ∆p
Durchuss Q
Durchusswiderstand ∆p
Durchusswiderstand ∆p
Durchussbereich 0 bis 50 l/min
Flow range 0 up to 120 l/min
Flow range Q Flow range Q
Flow range QFlow range Q
Flow range Q
Flow range pressure drop ∆p
Flow range pressure drop ∆p
Flow range pressure drop ∆p
Flow range 0 up to 500 l/min
Flow range 0 up to 1,000 l/min
Flow range 0 up to 50 l/min
Size 1xx2
Size 1xx4
Size 1xx5
Flow range 0 up to 10 l/min
Flow range pressure drop ∆pFlow range pressure drop ∆p
Flow range Q
Size 1xx7
Flow range pressure drop ∆p
Flow range 0 up to 3,000 l/min

Vorverstärker
Sensormodul
Messanschluss
Erdung
Ringschraube
Anschlusseinheit Anschlusseinheit mit Sensormodul
Anschlusseinheit Anschlusseinheit mit Sensormodul
Messanschluss
Anschluss
SAE 2
Vorverstärker Sensormodul Messanschluss G1/4 Erdung Ringschraube
Anschlusseinheit
AR. 2500-R.. Flanschanschlussmaße
DIN EN 1092
Gewicht 120 kg
FHG1xx5
FHG1xx7
Preamplier
Preamplier
Earthing
Earthing
Weight 81 kg
Weight 81 kg
Weight 120 kg
Sensor module
Sensor module
Connection unit with sensor
module AR. 800-H..
Connection unit with sensor
module AR. 800-X..
Connection unit
AR. 2500-R..
Connection unit
AR. 800-H..
Connection unit
AR. 800-X..
deep
Connection
Test Port
Ring bolt
Ring bolt
Flange connection dimension
Test Port
Test Port G 1/4
18

FHG1xx2
FHG1xx4
4 x M10-18 tief
Vorverstärker
Sensormodul
Messanschluss
Erdung
Anschlusseinheit
AR. 400-F..
Anschlusseinheit mit Sensormodul
AR. 400-F..
Anschlusseinheit
AR. 400-V..
Anschlusseinheit mit Sensormodul
AR. 400-V..
Gewicht 22 kg
Messanschluss
Anschluss
SAE 1 1/4 Gewicht 24,8 kg
M8-15 tief
beidseitig
4 x M14-25 tief
M8-15 tief
beidseitig
Preamplier
Preamplier
Earthing
Earthing
on both sides
on both sides
M8-15 deep
M8-15 deep
Weight 12 kg
Weight 12.7 kg
Weight 24.8 kg
Weight 22 kg
Sensor module
Test Port
Test Port
Sensor module
Connection unit with sensor
module AR. 100-E..
Connection unit with sensor
module AR. 100-T..
Connection unit with sensor
module AR. 400-F..
Connection unit with sensor
module AR. 400-V..
Connection unit
AR. 400-F..
Connection unit
AR. 400-V..
Connection unit
AR. 100-E..
Connection unit
AR. 100-T..
Connection
deep
Connection deep
Test Port
Test Port
24. FHG Flow Meter Dimensions
17