Omega Products FMG-421 Installation Manual

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FMG-400’s

Electromagnetic Flowmeters

(Flange type)

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It is the policy of OMEGA 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 Engineering, Inc. 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, patient connected
applications.

1

SAFETY PRECAUTIONS

Safety signs and labels affixed to the product and/or described in this manual give important

information for using the product safely. They help prevent damage to property and obviate

hazards for persons using the product.

Make yourself familiar with signal words and symbols used for safety signs and labels. Then read

the safety precautions that follow to prevent an accident involving personal injury, death or

damage to property.

Explanation of signal words

The signal word or words are used to designate a degree or level of hazard seriousness.

The signal words used for the product described in this manual are WARNING and CAUTION.

Indicates a potentially hazardous situation which,

WARNING

CAUTION

if not avoided, could result in death or serious
injury.

Indicates a potentially hazardous situation which,
if not avoided, may result in minor to moderate
injuries or in property damage.

Safety symbols

The following symbols are used in safety signs and labels affixed to a product and/or in the

manual for giving safety instructions.

Indicates an action that is prohibited. Simply DON’T do this action.
The

prohibited action is indicated by a picture or text inside or next to the

circle

Indicates an action that is mandatory. DO this action.
The

mandatory action is indicated by a picture or text inside or next to the

circle.

Indicates a potential hazard. The potentially hazardous situation is
indicated by a picture or text inside or next to the triangle.

2

SAFETY PRECAUTIONS (continued)

Safety Precautions for Installation and Wiring

WARNING

 Do not use the FMG400 Series in an explosive atmosphere.

Using this product in an explosive atmosphere can cause
explosion.

DON’T

CAUTION

 Turn off main power before working on

pipes.

Working on pipes while
power is applied can cause
electric shock.

DO

 Install a switch and fuse to isolate the

FMG400 Series from main power.

Power supply from main
power can cause electric

DO

 Turn off main power before conducting

wiring work.

shock or circuit
breakdown.

Wiring while power is
applied can cause electric
shock.

DO

 Do not conduct wiring work with bare

hands.

Remaining electric
charge even if power is

DON’T

 Do not work on piping and wiring with

wet hands.

turned off can still cause

electric shock.

Wet hands may result in
electric shock.

DON’T

 Use an appropriate device to carry and

install the FMG400 Series.

If this product falls to the
ground, injury, or malfunction of

DO

 Do not modify or disassemble the

FMG400 Series unnecessarily.

DON’T

 Ground the FMG400 Series independently

from power equipment.

DO

 Use crimped terminal lugs for the terminal

board and GND terminal.

DO

or damage to the product, can be
caused.

Modifying or disassembling this
product can cause electric shock,

malfunction of or damage to
this product.

Operating this product without
grounding can cause electric
shock or malfunction.

Loose connections can cause

electric shock, fire from
excessive current or system
malfunction.

The label shown left is placed
near the terminal board for power
input.
(A

black border and symbol on
yellow triangle)
Be alert to electric shock

3

SAFETY PRECAUTIONS (continued)

Safety Precautions for Maintenance and Inspection

CAUTION

 Do not touch the FMG400 Series

main body when high temperature
fluid is being measured.

The fluid raises the main
body temperature and can

DON’T

 Do not conduct wiring work with wet

hands.

cause burns when touched.

Wet hands may result in
electric shock.

DON’T

 Do not use a fuse other than the one

specified.

Using a fuse other than the
one specified can cause

DON’T

system failure, damage or
malfunction.

 Do not conduct wiring work when

power is applied.

Wiring while power is
applied can cause

DON’T

Use a rated fuse as follows depending
on the power specifications.

• Fuse rating:
1A/250V for 100 to 240 V

• Dimensions:
Diameter 5.2 mm × 20 mm

electric shock.

The label shown left is
placed near the terminal
board for power input.
(A

black border and
symbol on yellow
triangle)
Be alert to electric
shock.

ac

Disclaimer

OMEGA does not accept liability for any damage or loss, material or personal, caused as a
direct or indirect result of the operation of this product in connection with, or due to, the
occurrence of any event of force majeure (including fire or earthquake) or the misuse of this
product, whether intentional or accidental.

4

Handling Precautions

 To obtain the optimum performance from the FMG400 Series flowmeter for years of

continuous operation, observe the following precautions.

(1) Do not store or install the flowmeter in:

places where there is direct sunlight. If this is unavoidable, use an appropriate

•

sunshade.
places where excessive vibration or mechanical shock occurs.

•

places where high temperature or high humidity conditions obtain.

•

places where corrosive atmospheres obtain.

•

places submerged under water.

•

To put the flowmeter temporarily on the floor, place it carefully with something to
support it so that the flowmeter will not topple over.

(2) Execute wiring securely and correctly.

(3) Seal the cable thoroughly at the cable gland so that the cable is kept airtight.

(4) Ground the flowmeter with 100 ohm or less ground resistance. Avoid a common

ground used with other equipment where earth current may flow. An independent
ground is preferable.

(5) The converter housing covers and the cable glands are tightened securely at the time

of shipment. Do not remove these covers or glands unless it is necessary to wire new
cables or replace old ones.

Otherwise, gradual deterioration of circuit isolation or
damage to this product can be caused. Tighten the covers or cable glands securely
again if they have been removed.

(6) Make sure the fluid to be measured will not freeze in the detector pipe. This can

cause damage to the detector pipe.

(7) Select appropriate wetted materials suited for the process fluid to be measured.

Otherwise, fluid leakage due to corrosion can be caused.

(8) Observe the following precautions when you open the converter housing cover:

Do not open the cover in the open air unprotected against rain or wind. This can

•

cause electric

Do not open the cover under high ambient temperature or high humidity

•

shock or cause damage to the flowmeter electronics.

conditions or in corrosive atmospheres. This can cause deterioration of system
accuracy or cause damage to the flowmeter electronics.

(9) This product may cause interference to radio and television sets if they are used near

the installation site. Use metal conduits etc. for cables to prevent this interference.

5

Handling Precautions (continued)

(10) Radio transmitters such as transceivers or cellular phones may cause interference to

the flowmeter if they are used near the installation site. Observe the following
precautions when using them:

Do not use a transceiver whose output power is more than 5 W.

•

Move the antenna of a transceiver or a cellular phone at least 50 cm away from

•

the flowmeter and signal cables when using it. Do not use a radio transmitter or
a cellular phone near the flowmeter while it is operating online. The transmitter
or cellular phone’s output impulse noise may interfere with the flowmeter.

Do not install a radio transmitter antenna near the flowmeter and signal cables.

•

(11) For reasons of flowmeter failure, inappropriate parameters, unsuitable cable

connections or poor installation conditions, the flowmeter may not operate properly.
To prevent any of these problems causing a system failure, it is recommended that
you have preventive measures designed and installed on the flowmeter signal
receiving side.

6

Table of Contents

SAFETY PRECAUTIONS 2

Handling Precautions 5

1. Product Inspection and Storage 9

1.1 Product Inspection 9

1.2 Storage 9

2. Overview 10

3. Names of Parts 11

4. Installation 14

4.1 Location 14

4.2 Mounting 15

4.3 Piping Connections 19

5. Wiring 23

5.1 Cables 24

5.2 External Device Connections and Grounding 24

5.3 Digital I/O Connections 26

5.4 Wiring Procedure 27

6. Operation 30

6.1 Preparatory Check 30

6.2 Zero Adjustment 31

7. LCD Display and Controls 32

7.1 Outline 32

7.2 Display Format 34

7.3 Basic Operations 36

7.4 Configuration Items Selection Table 38

8. Configuration Parameter Setting 39

8.1 Configuration Items 39

8.2 Checking or Changing Parameters 40

9. Calibration 70

9.1 Calibration Items 70

9.2 Calibration Using Converter Signal Source 71

10. Digital I/O Functions 75

10.1 Digital I/O Specifications 76

10.2 Totalizer and Pulse Output 77

10.3 Multi-range Functions 79

10.4 High and Low Limit Alarms 84

7

10.5 Empty Pipe Alarm 86

10.6 Preset Point Output 87

10.7 Remote Zero Adjustment 89

10.8 Remote Selection of Fixed Value Output 90

10.9 Converter Failure Alarms 91

11. Self-Diagnostics and Alarms 92

11.1 Self-Diagnostics 92

11.2 Output Status for Errors and Alarms 95

12. Maintenance and Troubleshooting 96

12.1 Maintenance 96

12.2 Troubleshooting 98

13. Principle of Operation 101

14. Specifications 102

14.1 Flowmeter Specifications 102

14.2 Specification Code table 106

15. Outline Dimensions . 108

Appendix 1 . Electromagnetic Compatibility and Low Voltage Safety 110

Electromagnetic Compatibility 110

Low Voltage Safety 111

Appendix 2 . Default set value in each configuration item 112

8

1. Product Inspection and Storage

Upon arrival of the product package, open the package and check the items contained inside. If

you do not intend to install the product soon after opening the package, store the product and

other related items in a place such as described in 1.2 below.

1.1 Product Inspection

The FMG400 Series flange type electromagnetic flowmeter is shipped in a cardboard container

filled with shock-absorbing materials. Open the package carefully and check as follows:



Make sure the following items are included in the package.

(1) Model FMG400 Series falnge type Electromagnetic Flowmeter......

(2) Instruction Manual ...............................................................

(3) Operation Guide ....................................................................



Inspect the flowmeter for indications of damage that may have occurred during shipment.



Make sure the type and specifications of the flowmeter are in accordance with the

ordered specifications.

If you cannot find the items listed above or any problem exists, contact OMEGA.

1

1

1

1.2 Storage

To store the FMG400 Series flowmeter after opening the package, select a storing place as

follows and keep it under the conditions described below:

(1) Avoid places where there is direct sunlight, rain or wind.

(2) Store the product in a well-ventilated place. Avoid places of extremely high

humidity or extremely high or low temperature. The following environment is
recommended:

•

Humidity range: 10 to 90% RH (no condensation)

•

Storage temperature: –15 to +65° C

(3) Avoid places where vibrations or mechanical shock occurs.

(4) Do not leave the converter housing cover open . Open the cover only when you

actually start wiring cables. Leaving the cover open can cause gradual deterioration
of circuit isolation.

(5) To put the flowmeter temporarily on the floor, place it carefully with something to

support it so that the flowmeter will not topple over.

9

2. Overview

The FMG400 Series electromagnetic flowmeter measures the volumetric flow rates of

electrically conductive materials on the basis of Faraday's Law of Electromagnetic induction.

The device consists of two units: the detector, through which the fluid to be measured flows,

and the converter, which receives the electromotive force signals from the detector, then

converts the signals into the 4–20 mA

integrally mounted.

dc signal. These two units for the FMG400 Series are

Features

Every type of electromagnetic flowmeter has the following features:



Fluid flow is not obstructed and pressure loss is negligible.



The process fluid's temperature, pressure, density or flow conditions have no effect on
the accuracy of the flowmeter.



The flowmeter output is directly proportional to the process flow rate, thus it is easy to
read its output.

The FMG400 Series electromagnetic flowmeter has the following additional features:

(1) High accuracy, ±0.5% of rate is possible for 0.3–10 m/s velocity range.

(2) The flowmeter can be used to measure f

luids with solids (such as sludge or slurries)

for the reasons stated below:

The original noise-suppression circuit with signal processing capabilities

•

ensures a stable output.

(3) The flowmeter has various flow measurement output and control functions as standard

specifications and the LCD display for convenient parameter settings.

•

These functions can be selected with control keys on the panel.

(4) An easy-to-read LCD display (2-line × 16-character display)

The backlit LCD display can be read even under poor lighting conditions.

10

3. Names of Parts

N

play

The outline drawing of the FMG400 Series flange type flowmeter is shown in Figure 3.1 and

the internal views of the converter are shown in Figures 3.2 and 3.3.



Outline Drawing

Housing cover
for terminal board

Grounding terminal

ameplate

Port for power cable

Port for I/O

cable

Housing cover for

LCD dis

Detector

Converter

LCD display

Control keys

Flow derection arrow

Figure 3.1 Outline drawing of FMG400 Series flange type Flowmeter

11



Terminal Board of Converter

Power supply teminals

Internal ground terminal

Fuse

External grounding
terminal

Digital output terminals

Digital input terminal

宜しくお願い致します。

Figure 3.2 Terminal Board of Converter

Current output terminals

Signal COMMON for DI, DO1, DO2

CAUTION

The seal shown in the left figure is attached to near the

power supply wiring terminals. Be careful not to get

electric shock.

12



Control switch or keys of Converter

LCD display

Figure 3.3 Control switch or keys of Converter

Control keys

13

4. Installation

Safety Precautions for Installation

WARNING



Do not use the FMG400 Series in an

Using this product in an explosive atmosphere can
cause explosion.

explosive atmosphere

DON’T

CAUTION

 Install a switch and fuse to isolate the

FMG400 Series from main power.

Power supply from main
power can cause electric
shock or circuit breakdown.

DO

 Do not modify or disassemble the

FMG400 Series unnecessarily.

Modifying or disassembling
this product can cause

DON’T

 Do not work on piping and wiring with

wet hands.

electric shock,
or damage to this product.

Wet hands may result in

electric shock

malfunction

DON’T

.

 Use an appropriate device to carry and

install the FMG400 Series.

If his product falls to the
ground, injury, or malfunction

DO

 Ground the FMG400 Series

independently from power equipment.

of or damage to the product,
can be caused.

Operating this product without
grounding can cause electric
shock or malfunction.

DO

The label shown left is placed
near the terminal board for
power input.
(A

black border and symbol on
yellow triangle)
Be alert to electric shock.

4.1 Location

To select the installation site, follow the precautions described below:

 Avoid places where fluid runs in a pulsating form.

 Avoid places within the immediate proximity of equipment producing electrical

interference (such as motors, transformers, radio transmitters, electrolytic cells, or other
equipment causing electromagnetic or electrostatic interference).

14

 Avoid places where excessive pipe vibration occurs.

 Avoid places where there is direct sunlight. If this is unavoidable, use an appropriate shade

 Avoid places where corrosive atmospheres or high humidity conditions obtain.
 Avoid places of too great an elevation or constricted areas where clearance for installation

or maintenance work is not provided.

 Design piping so that the detector pipe is always filled with fluid, whether the fluid is

flowing or not.

 The detector has no adjustable piping mechanism. Install an adjustable short pipe where

needed.

 Chemical injections should be conducted on the downstream side of the flowmeter.

* For cautions on piping work such as the installation positions of piping and lengths of

straight pipes, see Section 4.3.

4.2 Mounting

CAUTION

 Use an appropriate device to carry

and install the FMG400 Series.

If his product falls to the
ground, injury, of

DO

malfunction of or damage
to the product, can be
caused.

 Turn off main power before

working on pipes.

Working on pipes while
power is applied can

DON’T

cause electric shock.

IMPORTANT

When high-temperature fluid is being measured, radiant heat from the detector pipe surface

and adjoining pipes may cause the ambient temperature of the converter to go above 60 °C.

If the ambient temperature goes above 60° C, try to lower the temperature by measures such

as wrapping heat-insulating materials over the detector pipe and adjoining pipes.

4.2.1 Piping Inspection

Before installing the pipes, make sure that there is no inclination of pipes or tube axial

displacement (eccentricity) as shown in Figure 4.1. Forced installation of the flowmeter in

inclined pipes may cause destruction of the detector or leakage of the fluid. Installing the

flowmeter in pipes with the presence of eccentricity may cause local friction of the lining or

earth ring and measurement errors depending on the properties of the fluid.

Before installing the pipes, flush the pipe interior to remove foreign matters in the pipes.

15

Eccentricit

y

Inclination

(a) Inclination of pipe (b) Tube axial displacement

(eccentricity)

Figure 4.1 Bad Examples with Inclination of Pipe and Tube Axial Displacement

(Eccentricity)

4.2.2 Cautions on Carrying Equipment

In order to prevent damages to the equipment, carry it packed as was at the time of delivery to

the installation location and unpack it there.

As the detector whose nominal diameter is 200 mm comes with eyebolts, lift the equipment as

shown in Figure 4.2 (a).

As the detector whose nominal diameter does not exceed 150 mm comes with no lifting means,

lift the equipment as shown in Figure 4.2 (b). The weights of the detectors with different

nominal diameters are described in Chapter 15 "Outline Dimensions."

Lifting the detector of any nominal diameter by pressing a bar into the detector pipe may

damage the lining, preventing stable measurement. Never do this under any circumstances.

* Lifting should be performed under instructions of qualified personnel of crane or slinging

work.

16

90° or less

(a) With nominal diameter of 200 mm (b) With nominal diameter of 150 mm or

less

Figure 4.2 Lifting Method

4.2.3 Mounting Procedure

To mount the FMG400 Series flange type, place it between the upstream and downstream pipe

flanges and tighten it with flange bolts and nuts. See Figure 4.3 and follow the procedure

below:

1. Insert two lower mounting bolts through the clearance holes in the upstream (or

downstream) pipe flange.

2. Install a packing next to the upstream (or downstream) flange face and the other packing

next to the downstream (or upstream) pipe flange. The two mounting bolts can now be
guided through the clearance holes in the downstream packing and flange.

3. Place the FMG400 Series flowmeter between the two flange packings, with the flowmeter

detector body above the two bolts. The flowmeter must be oriented in accordance with the
flow direction arrow.

4. Install the two upper mounting bolts through the clearance holes in the upstream and

downstream packings and flanges. Then install the remaining mounting bolts depending
on the flange pattern used.

5. Thread nuts on both ends of the 4 (or more) mounting bolts, finger tight.

17

6. While centering the flowmeter with the longitudinal axis of the pipeline, tighten the nuts

g

with a wrench diagonally across in even increments.

Note that the flowmeter detector pipe axis must be aligned with the pipeline axis on both

upstream and downstream sides. This is essential to have stable characteristics of flow

measurement (especially for flowmeters with meter sizes of 50 mm or less).

* In the case of a detector using teflon PFA lining, bolts may get loose with time because of

plastic deformation of teflon. Tighten them periodically.

Converter

Packing

Flow direction

Upstream flange

Detector

Figure 4.3 FMG400 Series flange type flowmeter-piping connections

Packin

Upper mounting bolts

Lower mounting bolts

Downstream flange

18

4.3 Piping Connections

(1)

(2)

(3)

)

(1) Required Pipe Length

If various joints are used upstream of the detector outlet, the straight pipe length as shown in

Table 4.2 is required.

Table 4.2 Required straight pipe length on the upstream side

90° bent

Tee

Diffuser

(4)Fully opened sluice valve

Detector

Detector

Detector

5. Other valves (not fully opened

Detector

L: Required straight pipe length—straight pipe length plus half-length of the detector.

D: Nominal bore size (diameter)

NOTES

1. The length of a reducer, if connected, can be counted as a part of the straight pipe length.

2. No straight pipe length is needed on the downstream side. If a butterfly valve is installed

downstream of the detector, do not let the valve plate protrude into the pipe of the detector.

19

(2) Pipe Orientation

The detector may be installed in horizontal, vertical or sloping pipe runs as shown in Figure 4.4.

However, except for horizontal installation, fluid should flow from lower to upper directions.

See Figure 4.4.

Flow direction

(a) Horizontal pipe installation

(b) Vertical pipe installation

(c) Sloping pipe installation

Detector

Ground surface

Figure 4.4 Detector Piping Orientation

The electrodes should be positioned horizontally against the ground surface in any piping

installation. See Figure 4.5.

Detector

-

-

Figure 4.5 Installation position of the detector

20

(3) Flow Direction

Install

the detector in accordance with the flow direction arrow on the detector. See Figure 4.6. If

the

actual flow runs opposite to the specified flow direction, the following display and output

appears. (For bi-directional multi-range measurement, see 10.3, “Multi-range Functions.”).

• LCD display : Instantaneous flow rate—indicates negative values,

Totalized flow—no counts added.

• Output: Current output— 4.0 mA output; Pulse output—No pulses

Figure 4.6 Flow direction arrow on the detector

(4) Preventing an Empty Pipe Condition

Design an upright pipe run (Figure 4.7) or sufficient head pressure (Fig. 4.8) at the downstream

detector outlet if there is a possibility of the detector pipe becoming emptied.

Figure 4.7 Detector with an upright pipe run at downstream outlet

Figure 4.8 Detector with sufficient head pressure at downstream outlet

21

(5) The pipes on both sides of the installation location of the detector should be fixed by attaching

support fittings, etc. Supporting the pipes will not only reduce piping vibration but also

prevent damages to the piping due to dead weight of the electromagnetic flowmeter and

weight of the fluid. (See Figure 4.9 and Figure 4.10.)

Piping support fitting Piping support fitting

Figure 4.9 Example of Pipe Fixing Method

Figure 4.10 Unsupported Piping Model

22

5. Wiring

CAUTION

Do not work on piping and wiring with

wet hands.

Wet hands can cause
system failure.

DON’T

 Do not modify or disassemble the
FMG400 Series unnecessarily.

Modifying or
disassembling this product

DON’T

Flowmeter accuracy may be affected by the way wiring is executed. Proceed with wiring

taking the following precautions:

(1) Select the cable runs away from electrical equipment (motors, transformers, or radio

transmitters) which causes electromagnetic or electrostatic interference.

(2) Deterioration of flowmeter circuit insulation occurs if the converter interior or cable

ends get wet or humidified. This in turn causes malfunction of the flowmeter or noise
problems. Avoid a rainy day if the flowmeter is to be installed outdoors. Even indoors,
prevent water from splashing over the flowmeter. Try to finish the wiring as quickly as
possible.

can cause electric shock,

malfunction of or damage

to this product.

 Ground the FMG400 Series properly.

Operating this product

without a grounding can

DO

cause system malfunction

The label shown left is placed
near the terminal board for
power input.
Be alert to electric shock.

(3) The converter has a surge-absorbing barrier installed inside. Therefore, do not conduct

a withstand voltage test for the converter. To check the insulation of the converter, use
a voltage of 250 V

dc or less.

23

5.1 Cables

Use the kind of cables shown in Table 5.1 to wire the converter.

Table 5.1 Cables

Name Cable type

Power cable

Three-wire sheathed

Nominal cross­sectional area

2 mm² 11 to 13 mm

Overall
diameter

cable (Note)

I/O cable

The number of wires for the output cable depends on the
system specifications. Use a shielded cable with nominal
cross-sectional area of 1.25 mm² and overall diameter of
11 to 13 mm.

Note: Use a four-wire cable if the arresters are to be used. See Figure 5.1 below.

5.2 External Device Connections and Grounding

The terminal board connections of the FMG400 Series flowmeter are shown in Figure 5.1.

Proceed with wiring as described in Section 5.4, “Wiring Procedure.”

If power supply is specified as DC, use L1 as positive (+) and L2 as negative (–) terminals.

1

To use the arresters, ground the GND terminal using a wire shown in broken line.

*

2

Locate an external double-pole power switch on the power line near the flowmeter and within

*

easy operation.
Mark on the switch as the disconnecting device for the flowmeter.
Use the proper switch as follows.

Recommended switch rating; Rating AC250V 6A or more

Inrush current 15A or more

Figure 5.1 Terminal Board Connections

24

IMPORTANT

(1) The grounding terminal of the FMG400 Series flowmeter should be grounded with

100 ohm or less ground resistance. Use a heavy copper braid or wire (cross-sectional
area 5.5 mm
terminal is M4 size and an M4-size crimped ring lug should be used to connect the
wire to the terminal. Avoid a common ground where earth current may flow.
independent
and non-conductive pipeline grounding procedures.

(2) To prevent a two-point grounding, ground the shielded cable on the receiving

instrument side.

2

minimum) to ground the terminal and make it as short as possible. The

An

ground is preferable. See Figure 5.2. for a conductive pipeline grounding

 If connection pipe is conductive:

(1) Connect between the grounding

terminal

and both ends of the mating
flanges with a heavy copper braid or
wire (cross sectional area 5.5 mm
minimum).

(2) If the conductive pipe is not

grounded

to a

good earth ground, use
the same type of copper braid or
wire

to

ground the terminal with 100

ohm or less ground resistance.

Grounding terminal

Grounding wire

 If connection pipe is non-conductive:

(1) Use a heavy copper braid or wire

(cross sectional area 5.5 mm²
minimum) to ground he terminal with

2

100 ohm or less ground resistance.

25

Figure 5.2 Grounding Procedure

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5.3 Digital I/O Connections

(

)

r

Digital I/O terminals consist of contact output terminals, voltage signal input terminal (DI), and

signal common terminal (COM). Each terminal (DO1, DO2 and DI) is isolated from internal

circuits. Terminal (COM) is the signal common for the other three terminals (DO1, DO2 and

DI).

Functions can be assigned for each terminal with the LCD control keys. See Chapter 10,

“Digital I/O Functions.”

To connect an electromagnetic relay or counter to the contact output terminal (DO1 or DO2),

put a surge-absorbing diode into the input circuit of the relay or counter. See Figure 5.3 for an

example of electromagnetic counter connection.

Solid-state relay Transistor open collector

Resisto

COM DI DO2 DO1

Diode

Note

* Note. Be sure to use a surge absorption diode with a rated current of 1 A and rated withstand

voltage of 200 V Min.

Figure 5.3 Electromagnetic Counter Connection Example

Power supply

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5.4 Wiring Procedure

Cable termination and cable connections are described below.

5.4.1 Cable Termination

CAUTION

 Do not conduct wiring work when

power is applied.

Wiring while power is
applied can cause electric

DON’T

Use cables as specified in Table 5.1. Remove about 30 mm of the end of cable sheath to expose

the two coated wires and then strip the wires about 10 mm. Then attach an M4-size crimped

ring-lug to the end of each wire using a compression tool. The crimped ring-lug should be of

the kinds with insulated sleeve to prevent shorts between adjacent terminals. The overall length

of the wire with the M4-size ring-lug attached should be about 35 mm. See Figure 5.4.

shock.

35 mm

 Do not work on piping and wiring

with wet hands.

Wet hands may result in
electric shock.

DON’T

Figure 5.4 Termination of cables

5.4.2 Cable Connections

Connect the terminated cable wires to the terminal board as described below.

IMPORTANT

Connect the wires securely to the terminal board. A loose connection may result in

unsatisfactory flowmeter performance. Make sure the wires are securely connected.

28

(1) Remove the cap nut from the cable gland and put the terminated cable through the cap nut,

seal ring, and packing as shown in Figure 5.5 on the right. The blank plate inside the cable

gland used when shipped is not needed once the cable is wired.

Figure 5.5 Cable connections

(2) Remove the housing cover for the terminal board shown in Figure 3.1. The terminal board is

located inside the converter as shown in Figure 3.2. Connect the crimped terminal of each

wire to the specified pin of the terminal board. See Figure 5.1 for the terminal board

configuration. Tighten each crimped terminal to the terminal board with a screw using a

Phillips screwdriver as shown in Figure 5.6. Loose connection may result in unsatisfactory

flowmeter performance. Make sure the wire is securely connected.

Figure 5.6 Terminal board connections

NOTE

The appropriate torque for tightening the terminal board screws is 1.2 Nm (12 kgf·cm).

29