ABB FMBA-01 User manual

ABB Drives
User’s Manual
Modbus Adapter Module
FMBA-01

Modbus Adapter Module
FMBA-01
User’s Manual
3AFE68586704 REV A EN
EFFECTIVE: 27.06.2005
2005 ABB Oy. All Rights Reserved.

Safety instructions
5
Safety instructions
Overview
This chapter states the general safety instructions that must be
followed when installing and operating the FMBA-01 Modbus
Adapter module.
The material in this chapter must be studied before attempting any
work on, or with, the unit.
In addition to the safety instructions given below, read the
complete safety instructions of the specific drive you are working
on.
General safety instructions
WARNING! All electrical installation and maintenance work on the
drive should be carried out by qualified electricians.
The drive and adjoining equipment must be properly earthed.
Do not attempt any work on a powered drive. After switching off
the mains, always allow the intermediate circuit capacitors 5
minutes to discharge before working on the frequency converter,
the motor or the motor cable. It is good practice to check (with a
voltage indicating instrument) that the drive is in fact discharged
before beginning work.
The motor cable terminals of the drive are at a dangerously high
voltage when mains power is applied, regardless of motor
operation.
There can be dangerous voltages inside the drive from external
control circuits even when the drive mains power is shut off.
Exercise appropriate care when working on the unit. Neglecting
these instructions can cause physical injury or death.

Table of contents
7
Table of contents
Safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
General safety instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table of contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Intended audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Before you start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
What this manual contains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Terms used in this manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
RS-485 standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
The FMBA-01 Modbus Adapter module . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Delivery check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Mechanical installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Electrical installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
General cabling instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
RS-485 connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Bus termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table of contents
8
Technical data and diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
FMBA-01 Modbus Adapter module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
RS-485 link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
LED indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Introduction
9
Introduction
Intended audience
The manual is intended for the people who are responsible for
commissioning and using an FMBA-01 Modbus Adapter module.
The reader is expected to have a basic knowledge of electrical
fundamentals, electrical wiring practices and how to operate the
drive.
Before you start
It is assumed that the drive is installed and ready to operate before
starting the installation of the extension module.
In addition to conventional installation tools, have the drive
manuals available during the installation as they contain important
information not included in this manual. The drive manuals are
referred to at various points of this document.
What this manual contains
This manual contains information on the wiring, configuration and
use of the FMBA-01 Modbus Adapter module.
Safety instructions are featured on the first few pages of this
manual.
Overview contains a short description of the RS-485 standard
and the FMBA-01 Modbus Adapter module and a delivery
checklist.
Mechanical installation contains placing and mounting
instructions for the module.
Electrical installation contains wiring, bus termination and
earthing instructions.

Introduction
10
Technical data and diagnostics contains information on physical
dimensions and connectors of the module and the specification of
the RS-485 link. It also explains how to trace faults with the status
LEDs on the FMBA-01 Modbus Adapter module.
Terms used in this manual
Communication Module
Communication Module is a name for a device (e.g. a fieldbus
adapter) through which the drive is connected to an external
communication network (e.g. a fieldbus). The communication with
the module is activated with a drive parameter.
FMBA-01 Modbus Adapter module
The FMBA-01 Modbus Adapter module is one of the optional
fieldbus adapter modules available for ABB drives. The FMBA-01
is a device through which an ABB drive is connected to a RS-485
network.

Overview
11
Overview
Overview
This chapter contains a short description of the RS-485 standard
and the FMBA-01 Modbus Adapter module, and a delivery
checklist.
RS-485 standard
RS-485 is a serial interface standard for communication over a
twisted-pair cable. Because the RS-485 signal transmission is
differential, it provides better protection against noise and longer
transmission distances than the RS-232. RS-485 is a half-duplex
multi-drop network, which means that multiple devices may reside
on line. Only one transmitter may be active at any given time.
The RS-485 standard specifies only the electrical characteristics
of the bus system. The communication protocol and
communication speed depend on the used application. For
example the electrical characteristics of the PROFIBUS and
MODBUS are based on the RS-485 standard.
The RS-485 transmission line consists of two wires, A and B. The
signal transmission is based on the voltage difference between
the wires. Minimum detected voltage difference is 200 mV. The
potential difference between the two wires determines the logic
state bit: when B is at higher voltage than A, the state is defined as
bit 1 (data high) and when A is at higher voltage than B, the state
is defined as bit 0 (data low).
The common mode voltage between RS-485 network devices is
limited to -5...+12 V. Ground wire and cable shield should be
connected to prevent common mode voltage between the network
devices from drifting outside the allowable limits.

Overview
12
RS-485 bus cable should be terminated with a 120 ohm resistor
on both ends to prevent signal reflection. When no device on the
network is transmitting, noise can be falsely interpreted as
communication data. To avoid this, termination can be included
with a fail-safe circuit (pull-up and pull-down resistors). The circuit
forces the bus into a known idle state when no device is
transmitting.
The FMBA-01 Modbus Adapter module
The FMBA-01 Modbus Adapter module is an optional device for
ABB drives which enables the connection of the drive to a RS-485
network. The FMBA-01 provides galvanic isolation between the
drive and RS-485 network and converts serial communication
signals of the drive to RS-485 signal levels.
The FMBA-01 has a built-in bus termination with fail-safe circuitry.
The termination can be activated with a jumper.
The adapter module is mounted into an option slot on the motor
control board of the drive. See the drive documentation for module
placement options.
Bus connector X1
(see chapter Electrical installation)
Diagnostic LEDs
(See chapter LED indications)
Other
RS-485
device
ABB drive Other
RS-485
device
Construction of the RS-485 network and the FMBA-01
Termination jumper J1
(See chapter Electrical installation)

Overview
13
Compatibility
The FMBA-01 Modbus Adapter module is compatible with all
stations that comply with RS-485.
Delivery check
The option package for the FMBA-01 Modbus Adapter module
contains:
• Modbus Adapter module, type FMBA-01
• this manual.

Mechanical installation
15
Mechanical installation
WARNING! Follow the safety instructions given in this manual and
the drive documentation.
Mounting
The FMBA-01 Modbus Adapter module is to be inserted into its
specific position in the drive. The module is held in place with
plastic pins and one screw. The screw also provides the earthing
of the fieldbus cable shield connected to the module.
On installation of the module, the signal and power connection to
the drive is automatically made through a 20-pin connector. (All
drives do not use all the available signals so the connector on the
drive may have fewer pins.)
Mounting procedure:
• Insert the module carefully into its position on the drive.
• Fasten the screw.
Note: Correct installation of the screw is essential for fulfilling the
EMC requirements and for proper operation of the module.

Electrical installation
17
Electrical installation
Overview
This chapter contains:
• general cabling instructions
• instructions for setting the bus termination
• instructions for connecting the module to the RS-485 network.
WARNING! Before installation, switch off the drive power supply.
Wait five minutes to ensure that the capacitor bank of the drive is
discharged. Switch off all dangerous voltages connected from
external control circuits to the inputs and outputs of the drive.
General cabling instructions
Arrange the bus cables as far away from the motor cables as
possible. Avoid parallel runs. Use bushings at cable entries.
RS-485 connection
RS-485 cable is connected to connector X1 on the FMBA-01
Modbus Adapter module.
X1 Description
1 SHLD Bus cable shield. Connected internally to
GND_B via an RC filter and directly to
CH_GND (chassis).
2 DATA_B Data positive
3 DATA_A Data negative
4 GND_B Isolated signal ground
1234

Electrical installation
18
Bus termination
Bus termination is required to prevent signal reflections from the
bus cable ends. The FMBA-01 Modbus Adapter module is
equipped with internal bus termination, which is configurable with
jumper J1 pins. Termination should be activated on devices
located at bus ends and deactivated on other devices. See the
figure below.
RS-485 device
ON
RS-485 device
OFF
RS-485 device
ONOFF
Term. Term. Term. Term.
RS-485 bus termination
J1
Termination
activated
Termination
activated
Termination
deactivated
Termination
deactivated
J1J1 J1
RS-485 device

Technical data and diagnostics
19
Technical data and diagnostics
FMBA-01 Modbus Adapter module
Enclosure:
Mounting: Into the option slot on the drive
Degree of protection: IP20
Ambient conditions: The applicable ambient conditions specified
for the drive in its manuals are in effect.
Indicators: Three LEDs (HOST, RXD, TXD)
Connectors:
• 20-pin connector to drive (X2)
• 4-pin detachable screw connector to bus (X1)
• 6-pin jumper block for bus termination configuration (J1)
Power supply:
• +3.3 V ±5% max. 150 mA (supplied by the drive)
65
63
21.35
133.3
20.5
74.4

Technical data and diagnostics
20
General:
• Estimated min. lifetime: 100 000 h
• All materials UL/CSA-approved
• Complies with EMC standards EN 50081-2 and EN 50082-2
• Bus interface functionally isolated from drive
RS-485 link
Compatible devices: All RS-485 compliant devices
Medium: Shielded twisted pair cable, impedance 100 to 150 ohm
• Termination: 120 ohms (built in the FMBA-01 Modbus Adapter
module)
Topology: Trunk line, drop lines allowed
Transfer rate: 5 Mb/s max.
Serial communication type: Asynchronous, half-duplex RS-485
Protocol: Depends on the used application. Typically Modbus.
LED indications
The FMBA-01 Modbus Adapter module is equipped with three
green diagnostic LEDs. The LEDs are described below.
Name Colour Function
HOST Green The module is powered up.
RXD Blinking
The module receives data from the
bus. The LED blinks whether the
received data is address to the unit
or not.
TXD Blinking The module sends data to the bus.

ABB Oy
AC Drives
P.O. Box 184
FI-00381 HELSINKI
FINLAND
Telephone [phone]
Fax [phone]
Internet http://www.abb.com
ABB Inc.
Automation Technologies
Drives & Motors
16250 West Glendale Drive
New Berlin, WI 53151
USA
Telephone [phone]
800-HELP-365
Fax [phone]
3AFE68586704 REV A EN EFFECTIVE: 27.06.2005