B&B Electronics MES1A User manual

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MES1A, MES1B
Modbus TCP to Modbus ASCII/RTU Converters

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International Headquarters
B&B Electronics Mfg. Co. Inc.
707 Dayton Road
Ottawa, IL 61350 USA
Phone [phone] -- General Fax [phone]
Website: www.bb-elec.com
[e-mail]
European Headquarters
B&B Electronics
Westlink Commercial Park
Oranmore, Co. Galway, Ireland
Phone [phone] -- Fax [phone]
Website: www.bb-europe.com
[e-mail]
© 2014 B&B Electronics –Revised Jan 2014
Document: MES1A-B_R2_0814m.doc

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CONTENTS
WARRANTY ............................................................................................ 7
CHAPTER 1: ABOUT YOUR MES1A/B CONVERTER...................................... 9
FEATURES ....................................................................................................... 10
CHAPTER 2: HARDWARE OVERVIEW ....................................................... 11
PACKAGE CHECKLIST......................................................................................... 11
INDICATORS,SWITCHES AND CONNECTORS .......................................................... 12
Power LED........................................................................................................... 12
Link LED............................................................................................................... 12
Activity LED......................................................................................................... 13
Reset Switch ........................................................................................................ 13
RS-422/485 Switch (MES1B only)........................................................................ 14
Ethernet Port Connector ..................................................................................... 14
DB-9M Serial Port Connector (MES1A only)........................................................ 14
RS-422/485 CONNECTOR (MES1B ONLY) ......................................................... 15
POWER CONNECTOR ........................................................................................ 18
CONNECTING THE HARDWARE ........................................................................... 18
CHAPTER 3: GETTING STARTED ............................................................... 20
QUICKSTART ................................................................................................... 20
Check the contents of your MES1A/B package. It should contain….................... 20
Set up the Hardware ........................................................................................... 20
Software Installation........................................................................................... 20
Discover the MES1A/B on the Network............................................................... 21
Configure the MES1A/B ...................................................................................... 21
Modbus Device Installation................................................................................. 21

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USING THE DEVICE INSTALLER SOFTWARE ............................................................ 22
System Requirements.......................................................................................... 22
Installing the Device Installer .............................................................................. 22
Starting the Device Installer................................................................................ 23
Discovering Devices............................................................................................. 23
Getting Device Details......................................................................................... 24
Connecting to the MES1A/B................................................................................ 25
CHAPTER 4: CONFIGURING THE MES1A/B ............................................... 27
NAVIGATING THE CONFIGURATION MENU ........................................................... 28
SAVING CONFIGURATION SETTINGS..................................................................... 29
QUITTING WITHOUT SAVING ............................................................................. 29
RECONFIGURING TO FACTORY SETTINGS .............................................................. 30
To Reconfigure the MES1A to Factory Settings:.................................................. 30
To Reconfigure the MES1B, to Factory Settings:................................................. 30
Network/IP Settings ............................................................................................ 30
IP Address............................................................................................................ 31
Default Gateway ................................................................................................. 32
Netmask .............................................................................................................. 33
Telnet Configuration Password ........................................................................... 33
SERIAL AND MODE SETTINGS ............................................................................. 34
Protocol............................................................................................................... 34
Serial Interface .................................................................................................... 36
MODEM/CONFIGURABLE PIN SETTINGS............................................................... 38
ADVANCED MODBUS PROTOCOL SETTINGS .......................................................... 38
Slave Address / Unit ID Source ............................................................................ 39
Allow Modbus Broadcasts................................................................................... 40

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Use MB/TCP 00BH/00AH Exception Responses .................................................. 41
Disable Modbus/TCP Pipeline ............................................................................. 42
Character Timeout .............................................................................................. 42
Message Timeout................................................................................................ 43
Serial TX Delay after RX....................................................................................... 43
Swap 4x/0H to Get 3x/1x .................................................................................... 43
UNIT ID TO IP ADDRESS LOOKUP TABLE SETTINGS................................................. 43
Close Idle TCP Sockets After ................................................................................ 44
Redundant Entry Retries After ............................................................................ 44
Add, Delete, Exit - Select Function...................................................................... 44
Modbus Address From/To................................................................................... 45
Slave IP Address .................................................................................................. 45
CHAPTER 5: USING OTHER DEVICE INSTALLER FEATURES......................... 46
MANAGING DEVICE LISTS .................................................................................. 46
Creating a New Device List.................................................................................. 46
Saving Device Lists .............................................................................................. 47
Opening Device Lists ........................................................................................... 47
Device List Display Options ................................................................................. 47
Adding a Device Manually .................................................................................. 49
ASSIGNING AN IP ADDRESS (USING DEVICE INSTALLER) .......................................... 50
Using Device Installer to Assign an IP Address.................................................... 50
USING THE DEVICES DETAILS TAB ....................................................................... 51
UPGRADING FIRMWARE.................................................................................... 52
INSTALLING PRE-SAVED CONFIGURATION FILES..................................................... 53
Saving Setup Records .......................................................................................... 54
Installing Setup Records ...................................................................................... 54

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LOGGING SEARCH AND UPGRADE DATA............................................................... 56
USING PING .................................................................................................... 57
USING HELP .................................................................................................... 58
CHAPTER 6: MODBUS BASICS ................................................................. 59
MODBUS ASCII/RTU....................................................................................... 59
MODBUS/TCP ................................................................................................ 60
HINTS AND TIPS ............................................................................................... 61
APPENDIX A: DEFAULT CONFIGURATION SETTINGS.................................. 62
APPENDIX B: PRODUCT SPECIFICATIONS................................................. 64
APPENDIX C: DIMENSIONAL DIAGRAMS ................................................. 68
APPENDIX D: SERIAL CONNECTIONS........................................................ 70
APPENDIX E: NETWORK CONNECTIONS .................................................. 73

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WARRANTY
Limited Lifetime Warranty
Effective for products of B&B Electronics Manufacturing Company shipped on or
after May 1, 2013, B&B Electronics Manufacturing Company warrants that each such
product shall be free from defects in material and workmanship for its lifetime. This
limited lifetime warranty is applicable solely to the original user and is not
transferable.
This warranty is expressly conditioned upon proper storage, installation, connection,
operation and maintenance of products in accordance with their written
specifications.
Pursuant to the warranty, within the warranty period, B&B Electronics
Manufacturing Company, at its option will:
1. Replace the product with a functional equivalent;
2. Repair the product; or
3. Provide a partial refund of purchase price based on a depreciated value.
Products of other manufacturers sold by B&B Electronics Manufacturing Company
are not subject to any warranty or indemnity offered by B&B Electronics
Manufacturing Company, but may be subject to the warranties of the other
manufacturers.
Notwithstanding the foregoing, under no circumstances shall B&B Electronics
Manufacturing Company have any warranty obligations or any other liability for: (i)
any defects resulting from wear and tear, accident, improper use by the buyer or use
by any third party except in accordance with the written instructions or advice of the
B&B Electronics Manufacturing Company or the manufacturer of the products,
including without limitation surge and overvoltage conditions that exceed specified
ratings, (ii) any products which have been adjusted, modified or repaired by any
party other than B&B Electronics Manufacturing Company or (iii) any descriptions,
illustrations, figures as to performance, drawings and particulars of weights and
dimensions contained in the B&B Electronics Manufacturing Company’s catalogs,
price lists, marketing materials or elsewhere since they are merely intended to
represent a general idea of the products and do not form part of this price quote and

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do not constitute a warranty of any kind, whether express or implied, as to any of the
B&B Electronics Manufacturing Company’s products.
THE REPAIR OR REPLACEMENT OF THE DEFECTIVE ITEMS IN ACCORDANCE WITH THE
EXPRESS WARRANTY SET FORTH ABOVE IS B&B ELECTRONIC MANUFACTURING
COMPANY’S SOLE OBLIGATION UNDER THIS WARRANTY. THE WARRANTY
CONTAINED IN THIS SECTION SHALL EXTEND TO THE ORIGINAL USER ONLY, IS IN LIEU
OF ANY AND ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, AND ALL SUCH
WARRANTIES AND INDEMNITIES ARE EXPRESSLY DISCLAIMED, INCLUDING WITHOUT
LIMITATION (I) THE IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE
AND OF MERCHANTABILITY AND (II) ANY WARRANTY THAT THE PRODUCTS ARE DO
NOT INFRINGE OR VIOLATE THE INTELLECTUAL PROPERTY RIGHTS OF ANY THIRD
PARTY. IN NO EVENT SHALL B&B ELECTRONICS MANUFACTURING COMPANY BE
LIABLE FOR LOSS OF BUSINESS, LOSS OF USE OR OF DATA INTERRUPTION OF
BUSINESS, LOST PROFITS OR GOODWILL OR OTHER SPECIAL, INCIDENTAL,
EXEMPLARY OR CONSEQUENTIAL DAMAGES. B&B ELECTRONIC MANUFACTURING
COMPANY SHALL DISREGARD AND NOT BE BOUND BY ANY REPRESENTATIONS,
WARRANTIES OR INDEMNITIES MADE BY ANY OTHER PERSON, INCLUDING WITHOUT
LIMITATION EMPLOYEES, DISTRIBUTORS, RESELLERS OR DEALERS OF B&B
ELECTRONIC MANUFACTURING COMPANY WHICH ARE INCONSISTENT WITH THE
WARRANTY, SET FORTH ABOVE.

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CHAPTER 1: ABOUT YOUR MES1A/B CONVERTER
Thank you for purchasing an MES1A or MES1B Modbus TCP to Modbus ASCII/RTU
Converter! Like all B&B Electronics products, this product has been manufactured to
the highest standards of quality and performance to ensure your complete
satisfaction.
MES1A and MES1B Modbus TCP to Modbus ASCII/RTU Converters are easy-to-use,
cost-effective solutions for connecting new and existing Modbus ASCII/RTU serial
devices to TCP/IP networks. The MES1A provides this connection for Modbus devices
with RS-232 interfaces; the MES1B facilitates Modbus devices with RS-422 four-wire
point-to-point interfaces, or RS-485 four or two-wire multi-drop bus connections.
MES1A and MES1B Converters
MES1A Converters allow new and legacy Modbus ASCII/RTU slave devices with RS-
232 serial ports to operate on a TCP/IP network as full Modbus TCP slaves. All
Modbus TCP devices on the network can share access to the Modbus ASCII/RTU
device.
MES1B Converters allow Modbus/RTU slave devices with RS-422/485 interfaces to
operate on a TCP/IP network as full Modbus TCP slaves. All Modbus devices on an
RS-485 bus can be connected to the TCP/IP network via the MES1B, allowing them all
to be accessed by Modbus TCP/IP devices on the network.
Traditional Modbus ASCII/RTU master devices also can be connected to TCP/IP
networks using the MES1A/B, making the device appear to be a full Modbus TCP

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master on the network. It can directly access Modbus TCP slave devices. It also can
access other Modbus ASCII/RTU slaves that are connected to the network via other
MES1A/B Converters, as if it is talking directly to a Modbus ASCII/RTU slave.
FEATURES
Converts Modus ASCII/RTU to Modbus/TCP
Small, economical and configurable
MES1A supports TD, RD and GND RS-232 lines
MES1B supports TDA(-), TDB(+), RDA(-), RDB(+) RS-422/485 lines
LEDs on network connection indicate link integrity and data transfer
activity
10/100 Mbps auto-detecting operation
Removable screw terminal strips for power supply
Removable screw terminal strips for RS-422/485 connection (MES1B)
Device Installer user interface software included
DIN rail mountable

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CHAPTER 2: HARDWARE OVERVIEW
PACKAGE CHECKLIST
MES1A/B Modbus ASCII/RTU to Modbus TCP Converters are shipped with the
following items included:
the MES1A or MES1B module
a printed version of this user manual
a printed version of the MES1A/B Quick Start Guide
a CD-ROM disc with
oDevice Installer software
othis manual in pdf format
oa Quick Start guide in pdf format

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INDICATORS, S WITCHES AND CONNECTORS
POWER LED
The Power LED illuminates (red) immediately on power up indicating that 10 VDC to
30 VDC power is present on the Power Supply terminals. (Typically 12 VDC is used.)
LED Indicators on the MES1A
LINK LED
When the Link LED located on the Ethernet jack is illuminated it indicates that a
connection (link integrity) has been established between the converter and the
network. Its color is green if connected to a 100BaseT network; orange if connected
to a 10BaseT network. It turns orange briefly during the power up process.

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ACTIVITY LED
When the Activity LED located on the Ethernet jack is flashing (green) it indicates
data is being sent across the network. This LED turns orange briefly during the power
up process.
LED
Color/Status
Function
Power
Red
Power applied
Link
Orange
Green
Bootup, 10BaseT
100BaseT
Activity
Green
(Blinking)
Orange
Data on the
network
Bootup
LED Status Table
RESET SWITCH
The Reset switch is accessible on the top edge of the MES1A/B (same edge as the
power supply connector) through a small hole in the MES1A/B enclosure. It allows
you to reset the MES1A/B by inserting a small tool through the hole and pressing the
momentary switch for about 1 second. The MES1A/B restarts with its last saved
configuration settings.

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RS-422/485 SWITCH (MES1B ONLY)
The RS-422/485 switch allows you to set the MES1B Converter for RS-422/485 four-
wire or RS-485 two-wire operation.
When the switch is in the left position, the MES1B operates in RS-
422/485 four-wire mode.
When the switch is in the right position, the MES1B operates in the RS-
485 two-wire mode.
ETHERNET PORT CONNECTOR
The Ethernet Port connector is a standard RJ-45 receptacle that allows the converter
to be connected to an Ethernet network. Two indicator LEDs (described above) are
built into the RJ-45 connector.
DB-9M SERIAL PORT CONNE CTOR (MES1A ONLY)
The Serial Port Connector on the MES1A is a DB-9 male connector (configured as a
DTE) supporting RS-232 serial communications including TD (Pin 3), RD (Pin 2) and
GND (Pin 5) signal lines. If the Modbus device you are connecting to the MES1A is
configured as a DCE you will use a straight-through serial cable. If the Modbus device
is configured as a DTE, use a null modem cable.
Refer to Appendix D for connection pin-outs.

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RS-422/485 CONNECTOR (MES1B ONLY)
The RS-422/485 connector on the MES1B is a five position removable terminal block
with screw downs. The connector provides screw connections for:
Terminal 1 - RDB(+)
Terminal 2 - RDA(-)
Terminal 3 - TDB(+)
Terminal 4 - TDA(-)
Terminal 5 –Ground
MES1B Serial Connector

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RS-422/485 FOUR-WIRE MODE
When the MES1B is configured to operate in RS-422/485 four-wire mode (RS-
422/485 switch in the left position) its receive terminals are connected to the
transmit terminals of the Modbus device it is communicating with. Its transmit
terminals are connected to the receive terminals of the Modbus device it is
communicating with.
RS-422/485 Four-Wire Connection

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RS-485 TWO-WIRE MODE
When the MES1B is configured to operate in RS-485 two-wire mode (RS-422/485
switch in the right position) the two-wire RS-485 two-wire communications cable
pair is connected to Terminals TDB and TDA. The communications cable
ground/shield is connected to GND.
RS-485 Two-Wire Connection
No jumpers are required to bridge the transmit
and receive lines in two-wire mode.

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POWER CONNECTOR
The Power Connector is a removable two-position screw terminal block with screw
down. The MES1A/B requires between 10 VDC and 30 VDC (3.6 Watts). Typically a 12
VDC power adapter is connected to the terminal block via bare wires. The terminal
block can be unplugged to remove the converter from service.
MES1A/B Power Connector
CONNECTING THE HARDW ARE
The MES1A is connected to its Modbus device via a DB-9M connector and an RS-232
cable. The MES1A is configured as a DTE. If the connected Modbus device is
configured as a DCE, use a straight-through cable. If the connected Modbus device is
configured as a DTE, use a null modem cable.
Always check the interface specifications of the
Modbus device to determine whether it is a DTE or
DCE before connecting.
The MES1B is connected to its Modbus device via the RS-422/485 terminal block. In
RS-422/485 four-wire mode a cable containing two pairs and a ground/shield is used.
In RS-485 two-wire mode a cable containing one pair and a ground/shield is used.
Power is supplied to the converter via the power supply terminal block.

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Typically, the MES1A/B is connected to the network via a hub switch or router using
standard straight-through CAT-5 cable. (If you are connecting the MES1A/B directly
to a PC’s network interface a crossover Ethernet cable is required.)
MES1A Connections
MES1B Connections

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CHAPTER 3: GETTING STARTED
QUICKSTART
The following section is a quick, step-by-step procedure that will assist you to get
started configuring the MES1A/B. Additional details on how to use the Device
Installer software to discover and connect to devices is included in the section
following this one. MES1A/B configuration details are included in Chapter 4.
Check the contents of your MES1A/B package. It should contain …
The MES1A or MES1B unit
A printed version of this user manual
A printed version of the MES1A/B Quick Start Guide
Software CD with Device Installer software, this manual, Quick Start guide
SET UP THE HARDWARE
Connect the MES1A/B to the network using an Ethernet cable.
Connect your PC to the network
Connect a 12 VDC power supply (not included) to the MES1A/B and apply power. (10
to 30 VDC, 3.6 Watts.)
SOFTWARE INSTALLATION
Insert the software CD and it should auto-start into the installation wizard.
Follow the on-screen installation wizard to install the Device Installer software.