Omega Products FMG600 Installation Manual

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Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 1 of 44

Content

1. APPLICATION ............................................................................................................................................. 2

2. MEASUREMENT PRINCIPLE ..................................................................................................................... 2

3. TECHNICAL DESCRIPTION ....................................................................................................................... 3

3.1. GENERAL .................................................................................................................................................................. 3

3.2. METER DESIGN ........................................................................................................................................................... 3

3.2.1. Remote version ............................................................................................................................................... 3 

3.2.2. Compact version .............................................................................................................................................. 4

4. TECHNICAL PARAMETERS ....................................................................................................................... 5

4.1. FLOW SENSOR ............................................................................................................................................................ 5

4.1.1. Selection of correct sensor size ....................................................................................................................... 5

4.1.2. Operational pressure of measured liquid .......................................................................................................... 6

4.1.3. Selection of electrode material ......................................................................................................................... 6

4.1.4. Sensor tube lining............................................................................................................................................. 6

4.1.5. Compact or remote meter version? .................................................................................................................. 6

4.1.6. Dimensions of flanged sensor .......................................................................................................................... 7

4.1.7. Dimensions Tri Clover sensor .......................................................................................................................... 8

4.1.8. Flow sensor specifications ............................................................................................................................... 9

4.2. ELECTRONIC UNIT BOX ................................................................................................................................................ 9

4.2.1. Electronic unit specifications .......................................................................................................................... 10

5. METER APPLICATION RULES..............................................................................................................................................11

5.1. SENSOR PLACEMENT IN PIPING ................................................................................................................................... 11

5.2. SENSOR GROUNDING ................................................................................................................................................ 14

5.2.1. Flanged version .............................................................................................................................................. 14

5.2.2 Tri Clover ......................................................................................................................................................... 15

6. FLOW METER INSTALLATION AND OPERATIONAL START ............................................................... 16

6.1. SENSOR INSTALLATION .............................................................................................................................................. 16

6.2. ELECTRIC CONNECTIONS OF INDUCTION FLOW METER ................................................................................................... 17

6.2.1. Connection to power source .......................................................................................................................... 17

6.2.2. Output signal connections ............................................................................................................................. 18

6.3. CONNECTION BETWEEN SENSOR AND ELECTRONIC UNIT (REMOTE VERSION) ...................... 18

6.4. CONNECTION BETWEEN SENSOR AND ELECTRONIC UNIT (REMOTE METER VERSION, PROTECTION CLASS IP 68) .................. 19

6.5. OPERATIONAL START ................................................................................................................................................ 19

6.5.1 Operational start .............................................................................................................................................. 19

6.5.2. Operational data ............................................................................................................................................. 20

6.5.3.1. Display formats of aggregate values .......................................................................................................... 22

6.5.3.2. Data reset ................................................................................................................................................... 22

7. PROGRAMMING........................................................................................................................................ 23

7.1. PROGRAMMING OF THE BASIC MENU ITEMS .................................................................................................................. 24

7.1.1. Displayed data ............................................................................................................................................... 24

7.1.2. Samples ........................................................................................................................................................ 25

7.1.3. Analog output ................................................................................................................................................ 26

7.1.4. Output function .............................................................................................................................................. 29

7.1.5. Electrode cleaning .......................................................................................................................................... 34

7.1.6. Serial line ...................................................................................................................................................... 35

7.1.7. Production data ............................................................................................................................................. 37

7.1.8. Dose setting .................................................................................................................................................. 39

7.1.9. Zero setting ................................................................................................................................................... 40

7.1.10. 100 percent ................................................................................................................................................. 40

7.1.11. Exit .............................................................................................................................................................. 40

7.2. THE PARAMETER SETTING MENU ................................................................................................................................ 42

7.3. THE PRODUCTION DATA MENU ................................................................................................................................... 43

8. STANDARD TESTS ................................................................................................................................... 44

9. CALIBRATION AND VERIFICATION TESTS ........................................................................................... 44

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 2 of 44

1. APPLICATION

Flow meters FMG600 SERIES are primarily used for measuring instantaneous flow rate and volume of water
or similar liquids passed through the meter. Flow meters shall only be used in standard non-explosive
environments.

Any installation of flow meter must be in conformity with technical conditions mentioned in this manual.

Measurements can be done in both flow directions, with high measurement accuracy over a wide range of
flow rates 0.33 to 32.8 ft/s (0.1 to 10 m/s). The minimum required conductivity of the measured medium is 20
µS/cm.

The measurement evaluation electronic unit includes a two-line alphanumeric display to show the measured
values where various operational parameters of the meter can be selected by means of an associated
keyboard. Available are two passive binary outputs (frequency, pulse and limit values), one active current
output and an output to connect a digital communication line. All meter functions and output parameters can
be reset during the meter operation.

Should the need arise; the user may combine any sensor of the FMG600 series with any electronic units
without re-calibration of the meter on a test stand. The only thing that needs be done is to enter into the
electronic unit memory the calibration constants and excitation frequency of the selected sensor; these data
are given on the rating plate of the sensor. The value of threshold flow rate shall be set between 0.5 and 1%
of the specified maximum flow rate.

2. MEASUREMENT PRINCIPLE

The function of an induction flow meter is based on Faraday’s induction law. The meter sensor consists
of a non-magnetic and non-conductive tube with two embedded measuring electrodes to pick up the induced
voltage. To create an alternating magnetic field, two coils are fitted onto the tube in parallel with the plane
defined by the active parts of the measuring electrodes. Now if a conductive liquid flows across magnetic

field B, voltage U will appear on the measuring electrodes proportional to the flow velocity v and the
conductor length l.

U = B x l x v

U induced voltage
B magnetic flux density

l distance between the measuring electrodes
v liquid flow velocity

As the magnetic flux density and distance between the electrodes are constant, the induced voltage is
proportional to the liquid flow velocity in the tube. The value of the volume flow rate can then be readily

determined as a product of the flow velocity and square section of the tube, Q = v x S.

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 3 of 44

3. TECHNICAL DESCRIPTION

3.1. General

The induction flow meter consists of a sensor through which the measured liquid flows and an electronic unit
where the low-level signal from the sensor is modified to a standardized form suitable for further processing
in various industrial electronic devices. The output signal is proportional to the volume flow rate of the
measured liquid. The only factor limiting the application of induction flow meters is the requirement that the
measured liquid shall be conductive and non-magnetic. The induction flow meter can be designed either as
a compact device or with the sensor separated from the associated electronic unit. In the former case, the
electronic unit is fitted directly onto the meter sensor, in the latter case it is connected to the sensor by
special cable.

The sensor design shall take into consideration the type of the measured liquid and its operational
parameters. To facilitate fitting into the liquid piping, the sensor can be provided with end flanges, threaded,
or it maybe of a flangeless design. The supply voltage, types of output signal and communication interface
can be selected according to the customer requirements.

The basic configuration of induction flow meter includes two insulated passive binary outputs (each with
an opt coupler including a transistor output), insulated RS485 communications, dry relay, 4-20 mA output
and the USB communication interface. This USB interface is not insulated as it is used for factory calibration
purposes only. Optional accessories to this basic configuration are INPUT1 and OUTPUT3 for batching (all
with galvanic separation) –B, empty pipe detection -EPT.

Upon fastening the connecting wires into the respective terminals, make sure to tighten the bolts holding the
lid of the electronic unit and seal the cable glands. Fit blinds into the unused gland openings.

3.2. Meter design

3.2.1. Remote version

Flanged sensor connected by a cable with the associated separate electronic unit.

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Dimensions of the box to accommodate separate electronic unit and the mounting bracket

7,9" (200)6" (152)

9,6" (245)

O

0

,

2

5

"

(

6

,

4

)

2" (50)

3,5" (90)

6,8" (173)

5,3" (135)

0,8" (20)

1,4" (35)

2,4" (60)

9,45" (243)

Page 4 of 44

3.2.2. Compact version

Compact design solution for a flanged sensor with associated electronic unit

Dimensions of the box to accommodate a compact version of the flow meter

COMFORT

3,5" (90)

5,3" (135)

7,9" (200)6" (152)

3

r

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 5 of 44

4. TECHNICAL PARAMETERS

4.1. Flow sensor

4.1.1. Selection of correct sensor size

The following table shows minimum and maximum flow rates for various sensor sizes and flow velocities
ranging from 0.33 to 32.81 ft/s (0.1 to 10 m/s). The operational flow-velocity range is best to choose 1.64 to

16.40 ft/s (0.5 to 5 m/s), see the diagram below. For lower flow velocities, the measurement accuracy is
worse while at higher flow velocities the turbulences at contact edges may cause undesirable interference.
Minimum and maximum flow rates for various sensor sizes

DIN

Operational flow rates and flow velocities for various sensor sizes

ANSI GPM l / s GPH m

inches

DN

15
20
25 1 0.79 79 0.05 5 47.6 4755 0.18 18

32 1 ¼­40

50 2 3.17 317 0.2 20 190 19020 0.72 72
65 2 ½

80 3 7.93 793 0.5 50 475.5 47552 1.8 180
100 4
125 5
150 6 28.62 2862 1.8055 180.55 1717 171711
200 8
250 10 79.25 7925 5 500 4755 475523 18 1800
300 12 111 11100 7 700 6657 665732 25.2 2520

Qmin Qmax Qmin Qmax Qmin Qmax Qmin Qmax

0.29 29 0.018 1.8 17.2 1712 0.065 6.5

0.528 52.8 0.0333

1.32 132 0.0833

1.98 198 0.125 12.5 118.9 11888 0.45 45

5.28 528 0.3333

12.33 1233 0.7777 77.77 739.6 73962

18.93 1893 1.1944 119.44 1136 113594

50.63 5063 3.194

3.33 31.7

8.33 79.3

33.33 317

319.4 3038

1

½

¾

½

3167 0.12 12

7925 0.30 30

31700 1.2 120

303764

/ hou

2.8 280

4.3 430

6.5 650

11.5 1150

g

–

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 6 of 44

4.1.2. Operational pressure of measured liquid

The standard versions of flow sensors have the following pressure rating:

Sensor size Pressure ratin

DN 15

DN 300 1/2” and 12” PN 10 (1.0 MPa) 145 PSI

4.1.3. Selection of electrode material

Standard electrodes made of Hastelloy C4. However, in special applications it may be necessary to select a
different material. On request, Omega can supply electrodes made of tantalum -TGE.

4.1.4. Sensor tube lining

Teflon

Teflon (PTFE) lining is a universal solution for highly corrosive liquids and temperatures ranging from -4 °F

to 302 °F (–20 to +150°C). Typical applications are in the chemical and food processing industries.

4.1.5. Compact or remote meter version?

Temperature of the liquid is lower than 122 °F (50°C): It is possible to use both, compact or remote
version. Using of the version is only question of the layout or customer wish.
Temperature of the liquid is higher than 122 °F (50°C): Must be used remote version!

To prevent electromagnetic interference via the connecting cable, the sensor and separate electronic unit
of the meter in the remote version should be located as close as possible to each other. The maximum cable
length depends on the conductivity of the measured liquid (see the following diagram). Standard cable length
is 19,7" (6 m). .

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 7 of 44

4.1.6. Dimensions of flanged sensor

Sensor dimensions for various rated diameters Line size (DN)

Flanges according standard ANSI B 16.5 150 lb/sq.in.

Nom. size DN

½" (15) 3.5 (89) 2.4 (62) 6.5 (164) 7.9 (200) 2.6 (66)
¾" (20) 3.9 (99) 2.4 (62) 6.7 (170) 7.9 (200) 2.6 (66)
1" (25) 4.3 (108) 2.8 (72) 7.1 (180) 7.9 (200) 3.8 (96)
1 ¼" (32) 4.6 (117) 3.2 (82) 7.8 (199) 7.9 (200) 3.8 (96)
1 ½" (40) 5.0 (127) 3.6 (92) 8.2 (209) 7.9 (200) 3.8 (96)
2" (50) 6.0 (152) 4.2 (107) 8.8 (223) 7.9 (200) 3.8 (96)

PN10 2 ½" (65) 7.0 (178) 5.0 (127) 9.6 (244) 7.9 (200) 3.8 (96)

3" (80) 7.5 (191) 5.6 (142) 10.2 (260) 7.9 (200) 3.8 (96)
4" (100) 9.0 (229) 6.4 (162) 11.0 (280) 9.8 (250) 3.8 (96)
5" (125) 10.0 (254) 7.6 (192) 12.2 (310) 9.8 (250) 5.0 (126)
6" (150) 11.0 (279) 8.6 (218) 13.4 (340) 11.8 (300) 5.0 (126)
8" (200) 13.5 (343) 10.8 (274) 15.7 (398) 13.8 (350) 8.3 (211)
10" (250) 16.0 (406) 14.6 (370) 18.9 (480) 17.7 (450) 8.3 (211)
12" (300) 19.0 (483) 16.5 (420) 21.1 (535) 19.7 (500) 12.6 (320)

* Dimension A (sensor height) is net of the electronic unit box (or terminal box in the remote meter
version).
Weights of the sensors are only approximate.

D

Inches (mm) d Inches (mm)

A*

Inches (mm)L Inches (mm) l Inches (mm)

Weight

lb (kg)

7 (3)
7 (3)
7 (3)
9 (4)

9 (4)
13 (6)
20 (9)

31 (14)
35 (16)
42 (17)
55 (26)

91 (41)
120 (54)
170 (77)

3

r

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 8 of 44

4.1.7. Dimensions Tri Clover sensor

Tri-Clover

Size DN/OD

Inch (mm)

ID GPM l / s GPH m

mm

Qmin Qmax Qmin Qmax Qmin Qmax Qmin Qmax

½ (12.70) 9.40 0.1094 11.0001 0.0069 0.6940 6.564 660.006 0.0248 2.4984
¾ (19.05) 15.75

0.3091 30.8812 0.0195

1.9483 18.546

1852.872 0.0702 7.0139

1 (25.40) 22.1 0.6087 60.8018 0.0384 3.8360 36.522 3648.108 0.1382 13.8096

1 ½ (38.10) 34.8 1.5074 150.7603 0.0951 9.5115 90.444 9045.618 0.3424 34.2414

2 (50.80) 47.5 2.8087 280.8756 0.1772 17.7205 168.522 16852.536 0.6379 63.7938

2 ½ (63.50) 60.2

4.5110 451.1493 0.2846

28.4631 270.660

27068.958 1.0246 102.4672

OD Outer Diameter
ID Inner Diameter

A

DN/OD

ID

L

Sensor dimensions for various rated diameters Line size (DN)

Flanges according Tri Clover
OD Outer Diameter
ID Inner Diameter

Size DN/OD

Inches (mm)

inches (mm)D Inches (mm)

½" (12.70) 0,37 (9.40)

ID

A*

Inches (mm)

L

Inches (mm)

2.9 (74) 5.6 (143) 5.4 (137)

¾" (19.05) 0,62 (15.75) 2.9 (74) 5.6 (143) 5.4 (137)

PN10

1" (25.40) 0,87 (22.1)

1 ½" (38.10) 1,37 (34.8)

2" (50.80) 1,87 (47.5)

2.9 (74) 5.6 (143) 5.4 (137)

3.7 (94) 6.4 (163) 5.4 (137)

4.1 (104) 6.8 (173) 5.4 (137)

2 ½" (63.50) 2,37 (60.2) 5.1 (129) 7.8 (199) 7.6 (192)

* Dimension A (sensor height) is net of the electronic unit box (or terminal box in the distributed meter
version).
Weights of the sensors are only approximate.

/ hou

D

Weight

lb (kg)

3.5 (1.6)

3.5 (1.6)

3.7 (1.7)

4.8 (4.8)

()
()

g

)

(

)

–

y

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 9 of 44

4.1.8. Flow sensor specifications

Sensor size Flanged sensors, ½ “ to 12 “ (DN 15 to DN 300)

Tri Clover, ½ " to 2 ½ "

Operational pressure PN 10 (1.0 MPa) for DN 15 to 300, Tri Clover

Mechanical connection Flanges acc. to 150# ANSI B

Tri Clover

grounding On flanges

Grounding rings

roundingelectrode

Limit flow velocities of measured liquid From 0.33 to 32.81 ft/s (0.1 m/s to 10 m/s)

Maximum temperature of measured liquid up to 302 ºF (150 ºC

Minimum conductivity of measured liquid 20 S/cm

Empty pipe alarm Optional from 2 “ (DN 50)-EPT

Lining Teflon

PTFE

Measuring electrodes Hastelloy C4 standard

Platinum/gold -GGE
Tantalum

TGE

Protection class IP 67

Storage temperature 14 to 158 ºF (-10 ºC to +70 ºC) at max. relative air

humidit

70%

4.2. Electronic unit box

The signal-processing electronic unit is accommodated in a cast aluminum box coated on the surface with
paint of hue RAL 1017. The box is held by four M5 bolts with hexagonal socket heads. Upon loosening the
bolts slightly the box can be rotated around horizontal axis through ±180°. At the rear of the box is a terminal
board under a lid held in position by six bolts with hexagonal socket heads. At the rear bottom part of the box
there are cable glands and a special valve preventing condensation of the air humidity inside the box. The
unused gland openings shall be blinded. The front panel of the box is fitted with a two-line background­illuminated display unit and a four-button membrane keyboard.

Prior to putting the meter in service, check the correct sealing of all active glands, blinding of the unused
ones and tightening of the bolts holding the terminal board lid.

(

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 10 of 44

4.2.1. Electronic unit specifications

Power source 230 V~ (+10 % / -15 %) / 50 ÷ 60 Hz optional

115 V~ (+10 % / -15 %) / 50 ÷ 60 Hz optional
24 V~ (+10 % / -15 %) / 50 ÷ 60 Hz optional
24 V =

Power consumption 15 VA

Line fuse T250 mA, T2,0 A (with power supply 24 V)

Electric shock protection according to

Automated disconnection from power source in TN-S network

standard CSN 332000-4-41

Box material Aluminum casting

Weight 6.6 lb (3.0 kg)

Ambient temperature 23 to 131 ºF (-5 °C to 55 °C) (protected from direct sun light)

Storage temperature 14 to 158 ºF (-10 °C to 70 °C) at relative air humidity not

exceeding 70 %

Flow velocity range 0.33 to 32.8 ft/s ( 0.1 to 10 m/s)

Maximum flow error 0.2 % for 10 to 100 % Qmax

0.5 % for 5 to 100 % Qmax

Zero adjustment Standard

Output 1 - passive output, insulated
Output 2 - passive output, insulated
Relay output
Active current output, insulated

Binary multi-function optocoupler 30 V/50 mA
Binary multi-function optocoupler 30 V/50 mA
Binary multi-function relay 30V DC /0,3 A,
Analog 0 (4) to 20 mA, max. Load 1000 Ohm

Serial communication ports USB (not insulated) for factory calibration only

RS 485 (insulated)

Protection class IP 67

±10 %)Standard

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 11 of 44

5. METER APPLICATION RULES

5.1. Sensor placement in piping

No chemical injection or batching unit (such as chlorine compound injector) should be located at the input
side of the sensor. The insufficient homogeneity of the flowing liquid may affect the flow-rate values indicated
by the meter.

The meter performance will be the best if the liquid flow in the piping is well stabilized; therefore it is
necessary to observe specific rules for the sensor placement in piping. In the contact planes between the
sensor and the adjoining piping sections should be no edges as these would cause flow turbulence. Make
sure that straight piping sections are provided before and after the sensor; their required length is
proportional to the inner diameter of the piping concerned.

If more than one flow-disturbing element such as pipe bend or fitting is located near the sensor, the required
length of straight piping section on the sensor side concerned should be multiplied by the quantity
of such elements.

In the cases of bi-directional flow-rate measurement, the same conditions concerning flow stability shall be
met at the input and output sides of the sensor.

Required straight piping sections Pipe narrowing

.

In the case where the pipeline nominal size is bigger
than nominal size of flow meter, it is necessary to use
conical reduction with the maximum slope 15°. In the
case of bi-directional flow, conical reduction must be
installed on both sides, both with minimum straight
piping 5 DN. In the case of horizontal installation,
eccentric reduction must be use to prevent bubbling.

Pipe narrowing sections with angles not exceeding 8° can be taken for straight sections (see picture above)

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 12 of 44

In the cases where the liquid is pumped, the flow sensor shall always be placed at the output side of the
pump to prevent underpressure in the piping which might damage the sensor. The required length of the
straight piping section between the pump and sensor is then at least 25 DN.

Pump in the piping Closing valve in the piping

For the same reason, the sensor shall be always placed before the closing valve in the piping.

The sensor can be fitted in the piping in either horizontal or vertical position. However, make sure that the
electrode axis is always horizontal and, if the sensor is mounted in a horizontal position, the flange section
for attachment of the electronic unit box faces upwards.

Design, Assembly and Service Manual

Induction flow meter FMG600 series

Page 13 of 44

Elektrode
axis

Electrode axis Sensor mounted in a vertical position

In the cases where the sensor is mounted in a vertical position, the flow direction shall always be upwards.

Risk of liquid aeration Permanent flooding of sensor

To ensure correct meter function at all times, the measured liquid shall completely fill up the sensor and no
air bubbles shall be permitted to accumulate or develop in the sensor tube. Therefore the sensor shall never
be placed in the upper pocket of the piping or in a vertical piping section where the flow direction is
downwards.
In piping systems where complete flooding of the piping cannot always be guaranteed, consider placing the
sensor in a bottom pocket where full flooding is sure.

If the sensor is located near a free discharge point, such point shall be by at least 2 DN higher than the top
part of the sensor.

Sensor placement near free discharge point