YSI MIQ-A-MOD User Manual

IQ SENSOR NET

MIQ/(A-)MOD

Operating Manual

ba76021e01 01/2012

Modbus RTU and RS 485 connection

for the IQ S

ENSOR NET system2020 XT USB

MIQ/(A-)MOD

Note

For the most recent version of the manual, please visit www.ysi.com

.

Contact YSI

1725 Brannum Lane
Yellow Springs, OH 45387 USA
Tel: [phone]

800-765-4974
Email: [e-mail]
Internet: www.ysi.com

Copyright © 2012 Xylem Inc.

2

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MIQ/(A-)MOD Contents

Modbus RTU und RS 485 connection for
the IQ S

ENSOR NET system 2020 XT USB

1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1.1 How to use this component operating manual . . . . . . . . . 5

1.2 Modbus and IQ S

ENSOR NET system 2020 XT USB . . . . 6

2 Safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.1 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.2 General safety instructions . . . . . . . . . . . . . . . . . . . . . . . . 8

3 Interface for the Modbus RTU . . . . . . . . . . . . . . . . . . . . . 9

3.1 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2 The Modbus module . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.2.1 Terminal connections . . . . . . . . . . . . . . . . . . . . 11

3.2.2 Connecting the Modbus cable . . . . . . . . . . . . . . 12

3.2.3 Setting/changing the address, baud rate and parity
16

3.2.4 Bus and module monitoring . . . . . . . . . . . . . . . 18

3.3 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

3.4 Modbus checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

3.5 Sensor administration under Modbus . . . . . . . . . . . . . . 22

3.5.1 Creating the assignment of sensor numbers . . 22

3.5.2 Creating the identical assignment of sensor

numbers in several systems . . . . . . . . . . . . . . . 22

3.5.3 Changing the assignment of sensor numbers . . 23

ba76021e01 01/2012

4 Data transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.2 Modbus query . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.3 Structure of the information . . . . . . . . . . . . . . . . . . . . . . 29

4.4 Sensor data block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

4.5 Data formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

5 What to do if ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

5.1 Fault diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

5.2 Error elimination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

6 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6.1 IQ SENSOR NET Component MIQ/(A-)MOD . . . . . . . . . . 37

6.2 Modbus module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

7 Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3

Contents MIQ/(A-)MOD

7.1 Ordering & Technical Support . . . . . . . . . . . . . . . . . . . . 39

7.2 Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

4

ba76021e01 01/2012

MIQ/(A-)MOD Overview

IQ Sensor Net Operating Manual

System

Operating

Manual

(Ring Binder)

IQ Sensor
Operating

Manual

MIQ Module

Operating

Manual

MIQ Terminal

Operating

Manual

Component Operating Manuals

1Overview

1.1 How to use this component operating manual

The present operating manual complements the system operating

Structure of the

ENSOR NET

IQ S

operating manual

manual for the IQ S
description of the MIQ/(A-)MOD module.

File this operating manual directly behind the system operating manual.

ENSOR NET system 2020 XT USB. Is contains the

ba76021e01 01/2012

Fig. 1-1 Structure of the IQ SENSOR NET operating manual

The IQ SENSOR NET operating manual has a modular structure like the

ENSOR NET system itself. It consists of the system operating

IQ S
manual and the operating manuals of all the components used.

The space in the ring binder behind the system operating manual is
intended for filing the component operating manuals. Please file all
component operating manuals here so that all information is quickly
available in one location.

5

Overview MIQ/(A-)MOD

1.2 Modbus and IQ SENSOR NET system 2020 XT USB

System communication The functional units of the IQ SENSOR NET are connected with one

another via a common line (Fig. 1-2). The line consists of two wires and
a shield. It transports digital information between the controller and the
other modules. At the same time, the line is used to supply all modules
with electrical voltage from a power supply unit. The power supply unit
is only required for power supply and is not used in the system
communication.

With the -MOD option, the MIQ/(A-)MOD module upgrades the system
communication by a Modbus interface. Via this interface, sensor data
can be queried with the Modbus RTU protocol. The Modbus interface
(RS 485) also enables a direct point-to-point connection from an
IQ S

ENSOR NET system to a Modbus master (e.g. PC or PLC).

Fig. 1-2 Functional units of the IQ SENSOR NET with connection to the Modbus

Note

All other general information on components, functions and operation
of the IQ S

ENSOR NET system 2020 XT USB is given in the system

operating manual.

With the A option, the MIQ/(A-)MOD module extends the

ENSOR NET system by a fully automatic air pressure compensation

IQ S
for D.O. sensors (see system operating manual).

6

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MIQ/(A-)MOD Safety instructions

2 Safety instructions

This component operating manual contains special instructions that
must be followed during the installation of the Modbus module. Thus, it
is essential to read this component operating manual before carrying
out any work using this sensor. In addition to this manual, the S
chapter of the IQ S

ENSOR NET system operating manual must be

followed.

Always keep this component operating manual together with the
system operating manual and all other component operating manuals
in the vicinity of the IQ S

ENSOR NET system.

Directions The following symbols indicate special features in the individual

chapters of this operating manual:

Note

indicates notes that draw your attention to special features.

AFETY

Note

indicates cross-references to other documents, e.g. operating
manuals.

2.1 Authorized use

Authorized use of the MIQ/(A-)MOD consists of its use as an interface
to a Modbus.
The technical specifications according to chapter 5 W
must be observed. Only operation according to the instructions in this
operating manual is authorized.

Any other use is considered to be unauthorized. Unauthorized use
invalidates any claims with regard to the guarantee.

HAT TO DO IF ...

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7

Safety instructions MIQ/(A-)MOD

2.2 General safety instructions

The MIQ/(A-)MOD is constructed and inspected in accordance with the
relevant guidelines and norms for electronic instruments (see chapter
5W

HAT TO DO IF ...).

It left the factory in a safe and secure technical condition.

Function and

operational safety

The failure-free function and operational safety of the MIQ/(A-)MOD is
only guaranteed if the generally applicable safety measures and the
special safety instructions in this operating manual are followed during
its use.

The failure-free function and operational safety of the MIQ/(A-)MOD is
only guaranteed under the environmental conditions that are specified

in chapter 5 WHAT TO DO IF ....

Safe operation If safe operation is no longer possible, the MIQ/(A-)MOD must be taken

out of operation and secured against inadvertent operation.
Safe operation is no longer possible if the MIQ/(A-)MOD:

 has been damaged in transport

 has been stored under adverse conditions for a lengthy period of

time

 is visibly damaged

 no longer operates as described in this manual.

If you are in any doubt, contact the supplier of your MIQ/(A-)MOD.

8

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MIQ/(A-)MOD Interface for the Modbus RTU

3 Interface for the Modbus RTU

The MIQ/(A-)MOD Modbus module enables to connect the

ENSOR NET system 2020 XT USB with all the sensors connected to

IQ S
it to the digital connection of a superordinate process control.

In the MIQ/(A-)MOD, the AnyBus-S Modbus RTU Modbus module of
the HMS INDUSTRIAL NETWORKS AB company is mounted for this.

Note

Further instructions for the installation and operation of a Modbus
network are given on the Internet under www.Modbus.org. Especially
recommendable is the "Aufbaurichtlinie PROFIBUS/FMS" (installation
guideline) issued by the PNO PROFIBUS user organization, (PNO
order number 2.111) with many practical installation tips that apply to
Modbus systems as well.

3.1 Scope of delivery

The scope of delivery of the MIQ/(A-)MOD module comprises:

 MIQ/MOD or MIQ/A-MOD

 Modbus module, AnyBus-S Modbus RTU,

mounted in the MIQ/(A-)MOD module

 4 x screwed cable glands with seals and blind plugs

 2 x ISO blind nuts (M4)

 2 x cheese-head screws (M4x16) with plastic washer

 1 x contact base

 2 x plastic tapping screws for fixing the contact base

 Screw for shielding terminal

 2 x washer for shielding terminal

 Insulating part of the shielding terminal

 Operating manual.

3.2 The Modbus module

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The Modbus module (AnyBus-S Modbus RTU) is mounted on the main
PCB of the MIQ/(A-)MOD module.

9

Interface for the Modbus RTU MIQ/(A-)MOD

AnyBus-S

Modbus RTU

2

4

ON

OFF

1

5

3

2

ON

OFF

Fig. 3-1 AnyBus-S Modbus RTU in the MIQ/MC(-A)-MOD

The AnyBus-S Modbus RTU is an interface that can be used to query
sensor data with the Modbus RTU protocol.

10

Fig. 3-2 Elements of the AnyBus-S Modbus RTU

1 Modbus RTU terminal strip

2 Modbus terminator switch

3 Dip switches to set the address, baud rate and

parity (see section 3.2.3)

4 LEDs for Modbus diagnosis

5 LED for module diagnosis

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MIQ/(A-)MOD Interface for the Modbus RTU

1

6

2

3

4

5

3.2.1 Terminal connections

Fig. 3-3 Terminal connections

Pin Name Function

1 --

2 --

3 A line Negative RxD/TxD according to RS 485

specification

4 B line Positive RxD/TxD according to RS 485

specification

5 --

6 Shield BUS cable screen, connected with PE

ba76021e01 01/2012

11

Interface for the Modbus RTU MIQ/(A-)MOD

(A)

(B)

(A)

instrument connected
at the Modbus,
e.g. MIQ/(A-)MOD

Modbus cable

3.2.2 Connecting the Modbus cable

The MIQ/(A-)MOD component can be connected at the Modbus end
(A) or with a loop-through (B).

An RS 485 point-to-point connection has to be installed as a
component at the end of the Modbus (A).

Fig. 3-4 Connection options of the MIQ/(A-)MOD at the Modbus cable,

(A) at the end or (B) with loop-through

Note

All cables with electrical characteristics according to EN 50170 are
suitable as a Modbus cable (e.g. all Profibus cables).

(A)

Connecting the

MIQ/(A-)MOD

component

at the Modbus end

1 Carefully strip the Modbus cable insulation for approx. 20 mm.

2 Bare the Modbus wires from the shielding braid and strip them

for approx. 5 mm.

3 Twist the shielding braid and cover it with approx. 15 mm

insulating tube.

4 Insert the Modbus cable into the module housing of the MIQ/

MC(-A)-MOD through the screwed cable gland.

5 Additionally insulate the transition between cable sheath and

insulating tube of the shielding braid (e.g. with insulating tape
or shrinkable tubing), so that no shielding braid is uncovered.

12

Fig. 3-5 Modbus cable with insulating tape

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MIQ/(A-)MOD Interface for the Modbus RTU

AnyBus-S

Modbus RTU

6 Connect the Modbus wires and shield to the terminal

connections of the Modbus module (connections ALine, BLine
and Shield, see section 3.2.1).

Fig. 3-6 Connection of the MIQ/(A-)MOD as a Modbus end device

7 Fasten the cap nut of the screwed cable gland.

8 Check and if necessary correct the position of the Modbus

terminator switch.
The switch must be in the ON position.

9 Perform the check:

 Check whether the wires and cables are screwed on tightly.

 Insulate open wires.

 Remove any cable remains from the MIQ/(A-)MOD module.

10 Close the MIQ/(A-)MOD module.

Note

Using a shielding terminal, connect the shield of the Modbus cable to
the potential equalization or grounding system of the plant in the vicinity
but outside of the MIQ module housing.

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13

Interface for the Modbus RTU MIQ/(A-)MOD

1

2

5

7

4

3

6

(B)

Connecting the

MIQ/(A-)MOD

component at the

Modbus with a loop-

through

To loop the Modbus cable through the MIQ/(A-)MOD component, a
shielding terminal is included in the scope of delivery.

Fig. 3-7 Shielding terminal with Modbus cable and shield connection cable

1 Screw

2 Washer

3 Insulating part of the shielding

terminal

4 Cable insulation of the Modbus cable

5 Shielding braid of the Modbus cable

6 Wires of the Modbus cable

7 Shield connection wire

1 Carefully strip the cable insulation of both Modbus cables for

approx. 35 mm.

2 Shorten the exposed shielding braid to approx. 15 mm.

3 Bare the Modbus wires for approx. 5 mm.

4 Feed both cables through the free cable glands into the

module housing of the MIQ/(A-)MOD.

5 Create a shield connection wire (7). To do so, strip a wire on

both ends for approx. 5 mm and 10 mm.

6 Insert a washer in the insulating part (3) of the shielding

terminal.

7 Feed both Modbus cables into the insulating part (3) and lead

them through the insulating part.

14

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MIQ/(A-)MOD Interface for the Modbus RTU

approx.

15 mm

approx.

15 mm

approx.

5 mm

4 2

6

7

1

3

AnyBus-S

Modbus RTU

8 Feed the long stripped end of the shield connection wire (7)

into the insulating part (3) of the shielding terminal.

9 Position the second washer and screw it tight.

Fig. 3-8 Shielding terminal with Modbus cable (view from above)

10 Shorten the wires of the shielding braid if they protrude over

the shielding terminal.

11 Put the Modbus wires together in pairs.

12 Connect the Modbus wires and shield to the terminal

connections of the Modbus module (connections ALine, BLine
and Shield, see section 3.2.1).

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Fig. 3-9 Looping the Modbus cable through an MIQ/(A-)MOD

15

Interface for the Modbus RTU MIQ/(A-)MOD

2

3

1

S1

S2

3

2

1

4

5

6

7

8

1

2

3

4

ON

OFF

13 Fasten the cap nut of the screwed cable gland.

14 Check and if necessary correct the position of the Modbus

terminator switch. The switch must be in the OFF position.

15 Perform the check:

 Check whether the wires and cables are screwed on tightly.

 Insulate open wires.

 Remove any cable remains from the MIQ/(A-)MOD module.

16 Close the MIQ/(A-)MOD module.

Note

Using a shielding terminal, connect the shield of the Modbus cable to
the potential equalization or grounding system of the plant in the vicinity
but outside of the MIQ module housing.

3.2.3 Setting/changing the address, baud rate and parity

Note

The address, baud rate and parity cannot be changed during operation.
Any changes become effective only after a system reset (see system
operating manual).

The settings are made at the DIP switches of the Modbus module:

Fig. 3-10 Dip switches

1 Dip switches to set the address

S1: Dip 1-7

16

2 Dip switches to set the baud rate

S1: Dip 8 and S2: Dip 1-2

3 Dip switches to set the parity

S2: Dip 3-4

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MIQ/(A-)MOD Interface for the Modbus RTU

Address A prerequisite for the configuration of the AnyBus-S Modbus RTU

Modbus module is the setting of its address. The setting of the address
is carried out with the dip switches, 1-7 (1). Each switch sets the value
0 or 1 for one digit of the seven-digit binary number. This enables
addresses of 0-127 to be set.

Examples:

Address Setting on S1, dip switches 1-7

invalid 0000000

1 0000001

30 0011110

127 1111111

Baud rate A prerequisite for the configuration of the AnyBus-S Modbus RTU

Modbus module is the setting of the baud rate. The setting of the baud
rate is carried out with the dip switches, 8,1,2 (2). Each switch sets the
value 0 or 1 for one digit of the three-digit binary number. This makes
seven valid settings possible.

Baud rate Setting on S1, dip switch 8

and S2, dip switches 1-2

invalid 000

1200 001

2400 010

4800 011

9600 100

19200 101

38400 110

57600 111

Parity A prerequisite for the configuration of the AnyBus-S Modbus RTU

Modbus module is the setting of the parity. The setting of the parity is
carried out with the parity dip switches, 3,4 (3). Each switch sets the
value 0 or 1 for one digit of the two-digit binary number. This makes
three valid settings possible.

Parity Setting on S2, dip switches 3-4

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invalid 00

None (2 stop bits) 01

Even (1 stop bit) 10

Odd (1 stop bit) 11

17

Interface for the Modbus RTU MIQ/(A-)MOD

4

1

2

3

3.2.4 Bus and module monitoring

The Modbus module has 4 LEDs for monitoring the bus and one LED
for monitoring the Modbus module. These 5 LEDs are important aids
for the monitoring and diagnosis of faults.

Bus monitoring The LEDs have the following meaning:

Fig. 3-11 LEDs for bus monitoring

LED Color Meaning

1 Flashes

green

Data exchange
(the module receives or transmits data.)

Off No data exchange

2 Red Bus error

(more than 10% of the received telegrams have
wrong CRC values.)

Off The module is operating or not initialized

3 Green Modbus is ready for operation

Off The module is not correctly initialized

4 Red The dip switches are set to invalid values

(all dip switches are set to Off or
to invalid values.)

Off The dip switches are set to valid values

18

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MIQ/(A-)MOD Interface for the Modbus RTU

Module monitoring A two-color LED (for position of the LED, see section 3.2) is used for

monitoring the Modbus module.

Monitoring function Color Flash

frequency

ASIC and FLASH ROM error Red 2 Hz

Module not initialized Green 2 Hz

Module initialized and in operation Green 1 Hz

RAM error Red 1 Hz

DPRAM error Red 4 Hz

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19

Interface for the Modbus RTU MIQ/(A-)MOD

3.3 Commissioning

To connect the IQ SENSOR NET to the Modbus, preparations are
required on the Modbus module, on the Modbus master and possibly
on the IQ S

ENSOR NET as well.

Preparing the Modbus

module

Configuring the Modbus

master

Preparing the

IQ S

ENSOR NET

1 Open the MIQ/(A-)MOD module (see system operating

manual).

2 Set the address with the 7 dip switches at the Modbus module

(S1: dip switches 1-7) (see section 3.2.3).

3 Set the baud rate with the 3 dip switches at the Modbus module

(S1: dip switch 8 and S2: dip switches 1-2) (see section 3.2.3).

4 Set the parity using the two dip switches on the Modbus

module (S2: dip switches 3-4) (see section 3.2.3).

5 Connect the cable to the Modbus with the terminals of the

Modbus module (see section 3.2.1).

6 Check and if necessary correct the position of the Modbus

terminator switch (see section 3.2.2).

7 Configure the Modbus master for the new component (see

Modbus documentation).

Preparations on the IQ SENSOR NET may be necessary if the system
should transmit the data of the sensors to the Modbus with a specific
assignment of the sensors to sensor numbers (S01 ... S20) (see
section 3.5).

20

Note

The sensor numbers are automatically assigned by the IQ S

ENSOR NET

in the order in which sensors are recognized by the system. The current
assignment of sensor numbers to the sensors can be seen in the List
of sensors (see System operating manual, chapter List of sensors).

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MIQ/(A-)MOD Interface for the Modbus RTU

3.4 Modbus checklist

The following checklist supports you when planning, projecting and
installing a Modbus plant with the IQ S
operation, you should be able to answer all questions with "Yes".

 Is the [bus system] (bus segment) installed without branch lines?

 Was the correct Modbus cable used (cord type A according to

EN 50170)?

 Are the poles of the signal lines A line and B line correctly connected

at all bus connections?

 Is it guaranteed that there is no short-circuit between A line, B line

and cable shielding?

 Is the shielding installed free of interruptions?

 Are the guidelines for shielding and grounding being observed, and

doesn't any unallowed potential equalization current flow
via the shielding?

ENSOR NET. For smooth

 Is the maximum cable length (per bus segment) observed for the

corresponding baud rate?

 Do all devices support the required baud rate?

 Are exactly two terminators switched on at the ends of the [bus

system] (bus segment)?

 Are the terminators supplied with voltage so the following applies:

U

B line

- U

> + 500 mV?

A line

 Do all devices have individual bus addresses?

 Have the devices been restarted after changing the bus address,

baud rate or parity (switched off and then on again)?

 Do the addresses projected in the master correspond to the actual

addresses?

 After commissioning:

Do all devices signal error-free behavior?

 Is it guaranteed that the Modbus master has consistent access

to the 16 byte sensor data structure?

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21

Interface for the Modbus RTU MIQ/(A-)MOD

3.5 Sensor administration under Modbus

Preparation of the IQ SENSOR NET for communication with the Modbus
may require, e.g. the following:

 Creating an IQ S

ENSOR NET system with specific assignment of

sensor numbers to sensors (see section 3.5.1)

 Creating several IQ S

ENSOR NET systems with the identical

assignment of sensor numbers to sensors (see section 3.5.2)

 Changing the order of the sensors in an already installed system

(see section 3.5.3)

3.5.1 Creating the assignment of sensor numbers

You want to install an IQ S

ENSOR NET system and, at the same time, to

create a specific sequence of sensor number assignments to the
sensors.

1 Carry out a system start without any sensors (see System

operating manual, chapter Installation).

2 Connect the sensors to the system in the required order. For

each sensor, wait until the sensor is recognized by the system
(see System operating manual, chapter Installation).

22

3.5.2 Creating the identical assignment of sensor numbers in several systems

You want to install several identical IQ S

ENSOR NET systems and, at

the same time, to create the same sequence of sensor number
assignments to the sensors in all systems.

1 Carry out a system start without any sensors (see System

operating manual, chapter Installation).

2 Connect the sensors to the system in the required order. For

each sensor, wait until the sensor is recognized by the system
(see System operating manual, chapter Installation).

3 Repeat steps 1 and 2 for all other systems and, while doing so,

keep to exactly the same order when connecting the sensors.

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MIQ/(A-)MOD Interface for the Modbus RTU

3.5.3 Changing the assignment of sensor numbers

You want to change the assignment of sensor numbers to the sensors
in an already running IQ S

ENSOR NET system.

1 Unplug all sensors from the IQ SENSOR NET.

Note

When the inactive datasets are deleted, all settings for the sensors are
deleted as well.

2 Delete all inactive datasets in the list of sensors (see System

operating manual, chapter Deleting inactive datasets of
sensors).

3 Connect the sensors to the system in the required order. For

each sensor, wait until the sensor is recognized by the system
(see System operating manual, chapter Installation).

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23

Interface for the Modbus RTU MIQ/(A-)MOD

24

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MIQ/(A-)MOD Data transmission

4 Data transmission

4.1 Overview

Data transmission is carried out via the RS 485 interface with the
Modbus RTU protocol.

The following sensor data is transmitted:

 Sensor number (Sxx)

 Sensor status

 Sensor model

 Status info of sensors

 Measuring mode

 Measured value status (main and secondary measured value)

 Main measured value

Determining the first

register to be read

 Secondary measured value

Note

The transmitted data of all IQ S
document, "IQ S

ENSOR NET sensors: encoded data for field bus

ENSOR NET sensors is given in the YSI

communication" (ba76073e). It is permanently updated when new
sensors are available and when the sensor software is modified (if the
modifications are relevant for the transmitted sensor data). The latest
version is available on the Internet, in the download area for operating
manuals. Use the search function for the download and search for
"ba76073e".

4.2 Modbus query

With each query of sensor data via the Modbus protocol, a block of
consecutive registers is read (up to all of the 240 registers).
For a query of sensor data, determine the first register and the number
of registers to be read (1 ... 240).

The first register to be read depends on the sensor number (Sxx) [1 ...
30] and the number of the sensor register (R) [1 ... 8]:

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[(Sxx - 1)]

* 8 + R.

Example: Determine the first register with data for the sensor S10:
[(10 - 1)

* 8] + 1 = 73

25

Data transmission MIQ/(A-)MOD

Determining the number

of registers to be read

Example of a

Modbus query

and Modbus response

The number of registers to be read is maximum 240.

Example: Read all data of X sensors

Number of sensors

Number of registers

(X)

18

216

324

...

...

30 240

Query of all sensor information of the sensor with the sensor number
S02:

Modbus query

Byte Value Information Meaning of the value

1 01h Modbus address of

01h --> 1

the MIQ/MC-MOD

2 04h Function 04h --> 4

Read Input Register

(see section 4.3)

3 00h Start address HI 0008h --> 8

Start with register 9

4 08h Start address LO

(Modbus counting method)

5 00h Number of HI registers 0008h --> 8

6 08h Number of LO

8 registers

registers

7 70h CRC (HI) Checksum (CRC)

8 0Eh CRC (LO)

26

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MIQ/(A-)MOD Data transmission

Response with all sensor information of the sensor with the sensor
number S02:

Modbus response

Byte Value Information Meaning of the value

1 01h Modbus address of the

01h --> 1

MIQ/MC-MOD

2 04h Function 04h --> 4

Read Input Register

3 10h Number of bytes 10h --> 16

16 Byte (8 registers)

4 02h Contents of register 9

(HI)

02h (Int 8) --> 2
Sensor number S02

= sensor number

5 02h Contents of register 9

02h (Int 8) --> MEASURE
(LO)
= sensor status

6 04h Contents of register 10

(HI)
= sensor model

0401h (Int 16)

--> VisoTurb 700 IQ

7 01h Contents of register 10

(LO)
= sensor model

8 00h Contents of register 11

(HI)
= status info

0000h (Int 16)

--> no errors

ba76021e01 01/2012

9 00h Contents of register 11

(LO)
= status info

10 00h Contents of register 12

(HI)
= measuring mode

11 14h Contents of register 12

(LO)
= measured value
status

00h (Int 8) --> FNU Trüb

14h (Int 8)

Main measured value (bits

7-4):

1h --> VALID

Secondary measured

value (bits 3-0):

4h --> MISSING

27

Data transmission MIQ/(A-)MOD

Modbus response

Byte Value Information Meaning of the value

12 42h Contents of register 13

(HI)
= main measured
value

429E46C2h (Float 32)

--> 79,1382
Measured parameter and

13 9Eh Contents of register 13

(LO)
= main measured

unit, see byte 10
(measuring mode)

value

14 46h Contents of register 14

(HI)
= main measured
value

15 C2h Contents of register 14

(LO)
= main measured
value

16 00h Contents of register 15

(HI)
= secondary measured
value

00000000h (Float 32)

--> 0
but measured value invalid

17 00h Contents of register 15

(LO)
= secondary measured

(MISSING),
see Byte 11 (measured
value status)

value

18 00h Contents of register 16

(HI)
= secondary measured
value

19 00h Contents of register 16

(LO)
= secondary measured
value

20 23h CRC (HI) Checksum (CRC)

21 5Eh CRC (LO)

28

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MIQ/(A-)MOD Data transmission

4.3 Structure of the information

Sensor data block The datasets of up to 30 sensors (20 IQ SENSOR NET sensors and 10

differential sensors) of the IQ S
Modbus in a sensor data block in the controller of the IQ S

ENSOR NET are made available to the

ENSOR NET.

Query and response

telegram

Supported

Modbus commands

Data transmission takes place via query and response telegrams. The
form of the telegrams is determined by the Modbus RTU protocol.
The Modbus master transmits a query telegram with a Modbus
command to a Modbus slave. The Modbus slave transmits a response
telegram with the requested data from the sensor data block or an error
message.

The IQ S

ENSOR NET provides the data block for read access only.

Writing Modbus commands are not carried out.

Modbus commands Command code

Read Input Register 04h

Read Discrete Inputs 02h

Read Holding Register 03h

Read Coils 01h

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29

Data transmission MIQ/(A-)MOD

4.4 Sensor data block

The data block contains the data of up to 30 sensors in the order of
registering on the IQ S

The data of a sensor are stored in 8 registers each.
Thus, the sensor data block consists of altogether 240 registers. Each
register contains 2 bytes. The bytes 0 and 1 form register 0001, the
bytes 2 and 3 form register 0002, etc.

Modbus Information Data format

ENSOR NET (Sxx number).

Register

Bit Data

type

0001 1-8 1 [= sensor number (S01)] (Int 8) 7-0

0001 9-16 Sensor status (Int 8) 7-0

0002 1-16 Sensor model (Int 16) 15-0

0003 1-16 Status info (Int 16) 15-0

0004 1-8 Measuring mode (Int 8) 7-0

0004 9-16 Measured value status (Int 8) 7-0

Sensor S01

0005 1-16 Main measured value (IEEE-754 floating point, 32-bit) (Float 32) 31-16

0006 1-16 Main measured value (IEEE-754 floating point, 32-bit) (Float 32) 15-0

0007 1-16 Secondary meas. value (IEEE-754 floating point, 32-bit) (Float 32) 31-16

0008 1-16 Secondary meas. value (IEEE-754 floating point, 32-bit) (Float 32) 15-0

0009 1-8 2 [= sensor number (S02)] (Int 8) 7-0

0009 9-16 Sensor status (Int 8) 7-0

0010 1-16 Sensor model (Int 16) 15-0

Bit

0011 1-16 Status info (Int 16) 15-0

0012 1-8 Measuring mode (Int 8) 7-0

0012 9-16 Measured value status (Int 8) 7-0

Sensor S02

0013 1-16 Main measured value (IEEE-754 floating point, 32-bit) (Float 32) 31-16

0014 1-16 Main measured value (IEEE-754 floating point, 32-bit) (Float 32) 15-0

0015 1-16 Secondary meas. value (IEEE-754 floating point, 32-bit) (Float 32) 31-16

0016 1-16 Secondary meas. value (IEEE-754 floating point, 32-bit) (Float 32) 15-0

30

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MIQ/(A-)MOD Data transmission

Modbus Information Data format

Register

Bit Data

type

0017 ... 0232

Sensors S03 ... S29

...

...

...

0233 1-8 30 [= sensor number (S30)] (Int 8) 7-0

0233 9-16 Sensor status (Int 8) 7-0

0234 1-16 Sensor model (Int 16) 15-0

0235 1-16 Status info (Int 16) 15-0

0236 1-8 Measuring mode (Int 8) 7-0

0236 9-16 Measured value status (Int 8) 7-0

Sensor S30

0237 1-16 Main measured value (IEEE-754 floating point, 32-bit) (Float 32) 31-16

Bit

...

0238 1-16 Main measured value (IEEE-754 floating point, 32-bit) (Float 32) 15-0

0239 1-16 Secondary meas. value (IEEE-754 floating point, 32-bit) (Float 32) 31-16

0240 1-16 Secondary meas. value (IEEE-754 floating point, 32-bit) (Float 32) 15-0

Note

The counting method of the Modbus registers and Modbus bits and the
allocation of MSB and LSB is different from the usual method of most
programming languages.

Modbus Usually

Counting start of the register 1 0

MSB* allocation of the register Bit 1 Bit 15

MSB* allocation of the register Bit 16 Bit 0

MSB = Most significant bit, LSB = Least significant bit

ba76021e01 01/2012

31

Data transmission MIQ/(A-)MOD

MSB* LSB*

SEEEEEEE

EMMMMMMM

M M M M M M M M

M M M M M M M M

)2...2221(21

23

0

3

20

2

21

1

22

127 −−−−−

⋅++⋅+⋅+⋅+⋅⋅−=

bbbb

ES

MMMMV

)2...222(21

23

0

3

20

2

21

1

22

126 −−−−−

⋅++⋅+⋅+⋅⋅⋅−=

bbbb

S

MMMMV

4.5 Data formats

The sensor data in the sensor data block (see section 4.4) are available
in the Float 32, INT16 and INT8 data formats.

Float 32 The data for the main and secondary measured values are transmitted

in the IEE-754 standard 32-bit floating point format.

Bit representation Byte Bit

4 31 - 24 S = sign (bit 31)

323 - 16

215 - 08

107 - 00

E = Exponent (Bit 30-23)
M = mantissa (bits 22-0)

MSB = Most significant bit, LSB = Least significant bit

If not all of the bits of the exponent are 0, the value is calculated
according to:

If all of the bits of the exponent are 0, the value is calculated according
to:

A value is 0 if all the bits of both the exponent as well as the mantissa
are 0.

Note

If the measured value is equal to 0, check the measured value status.
If the measured value status is not equal to 1, an error has occurred
and the measured value is invalid.

Note

The Modbus protocol does not define how the bytes of 32-Bit-IEEE-754
floating point numbers should be ordered.

32

Apart from the byte order described in the bit representation, another
order of the bytes is also possible.
Opposite to the order described, the two lower bytes have been
exchanged with the two upper bytes in this order (b4 b3 b2 b1 - b2 b1
b4 b3).

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MIQ/(A-)MOD Data transmission

MSB LSB

For Modbus applications that can independently interpret floating point
numbers (or allow to select a data format for certain registers), the byte
order the data interpretation is based on should be checked.

INT16 In the INT16 format, the data for the sensor model and status info is

transmitted. The data consists of two bytes. The assignment is carried
out in Motorola format ("big-endian", the higher value byte first).

Bit representation Information

High byte

Low byte

INT8 All other data are transmitted in the INT8 format. This data consists of

one byte.

The data for the measured value status of the main and secondary
measured values are encoded jointly into a single byte. Bits 7-4 encode
the status of the main measured value, bits 3-0 encode the status of the
secondary measured value.

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33

Data transmission MIQ/(A-)MOD

34

ba76021e01 01/2012

MIQ/(A-)MOD What to do if ...

5 What to do if ...

5.1 Fault diagnosis

A simple diagnosis of the operability of the Modbus module and
communication with the Modbus is possible via the LEDs on the
Modbus module in the MIQ/MC (-A)-MOD (see section 3.2.4).

5.2 Error elimination

Data transmission

between the Modbus

master and

IQ S

ENSOR NET system is

The Modbus master

does not receive any

plausible input data

faulty

Cause Remedy

– Incorrect wiring of the

connections on the terminal
strip

– Incorrect setting of address,

baud rate, parity

– Check/change the connections

on the terminal strip (see
section 3.2.1)

– Check/change the settings

(see section 3.2.3)

– Incorrect protocol – Adapt the protocol

– Modbus module defective – Send MIQ/MC(-A)-MOD

module to YSI

Cause Remedy

– The data interpretation is not

correct

– Observe data formats of the

MIQ/MC(-A)-MOD (see also
section 4.5).

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35

What to do if ... MIQ/(A-)MOD

36

ba76021e01 01/2012

MIQ/(A-)MOD Technical data

6 Technical data

6.1 IQ SENSOR NET Component MIQ/(A-)MOD

General technical data for the IQ SENSOR NET are given in the system
operating manual for the 2020 XT USB system.

Electrical data

Nominal voltage Max. 24

VDC via the IQ S
chapter T
IQ S

ENSOR NET system operating manual).

Power consumption 3 W

Protective class III

ENSOR NET (for details, see

ECHNICAL DATA of the

Instrument safety

Terminal connections

Number of

1
MIQ/(A-)MOD modules
in an IQ S

ENSOR NET

system

Applicable norms – EN 61010-1

– UL 3111-1

– CAN/CSA C22.2 No. 1010.1

IQ SENSOR NET
connections

2

2 additional SENSORNET terminators that

can be activated (terminating resistors)

Terminal type Screw-type terminal strip, accessible by

opening the lid

Terminal ranges Solid wires:

0.2 ... 4.0 mm

2

AWG 24 ... 12

Flexible wires:

0.2 ... 2.5 mm

2

ba76021e01 01/2012

Cable feeds 4 cable glands M16 x 1.5 on the underside

of the module

37

Technical data MIQ/(A-)MOD

6.2 Modbus module

Information on the technical data of the AnyBus-S Modbus RTU
module from the HMS INDUSTRIAL NETWORKS AB company is
given in the documentation of the HMS INDUSTRIAL NETWORKS AB
company.

Note

Further information on the technical data of the Modbus module is
given on the Internet under the address of the manufacturer

HMS INDUSTRIAL NETWORKS AB
(www.hms-networks.com)

in the following documents:

 FIELDBUS APPENDIX

ANYBUS-S Modbus RTU

 AnyBus Slave Design Guide

ANYBUS-S Parallel Interface

38

ba76021e01 01/2012

MIQ/(A-)MOD Contact Information

7 Contact Information

7.1 Ordering & Technical Support

Telephone

Fax

: [phone]

Email

Mail: YSI Incorporated

Internet

When placing an order please have the following information available:

YSI account number (if available) Name and Phone Number
Model number or brief description Billing and shipping address
Quantity Purchase Order or Credit Card

: [phone]

[phone]
Monday through Friday, 8:00 AM to 5:00 PM ET

: [e-mail]

1725 Brannum Lane
Yellow Springs, OH 45387
USA

: www.ysi.com

7.2 Service Information

YSI has authorized service centers throughout the United States and
Internationally. For the nearest service center information, please visit

www.ysi.com

directly at 800-897-4151.

When returning a product for service, include the Product Return form
with cleaning certification. The form must be completely filled out for an
YSI Service Center to accept the instrument for service. The Product
Return form may be downloaded at www.ysi.com
‘Support‘ tab.

and click ‘Support’ or contact YSI Technical Support

and clicking on the

ba76021e01 01/2012

39

Contact Information MIQ/(A-)MOD

40

ba76021e01 01/2012

1725 Brannum Lane
Yellow Springs, Ohio 45387 USA
[phone]
800-765-4974 (US)
FAX [phone]
Email: [e-mail]
Internet: www.ysi.com