NETWORK GATEWAY SERIES ICC INDUSTRIAL CONTROL COMMUNICATIONS, INC. ICC INDUSTRIAL CONTROL COMMUNICATIONS, INC. Madison Office 1600 Aspen Commons, Suite 210 Middleton, WI USA 53562-4720 Tel: [608] 831-1255 Fax: [608] 831-2045 http://www.iccdesigns.com MBP-100 Houston Office 12300 Dundee Court, Suite 212 Cypress, TX USA 77429-8364 MODBUS PLUS MULTIPROTOCOL NETWORK GATEWAY Printed in U.S.A August 2008 ICC #10498-3.
Introduction Thank you for purchasing the ICC MBP-100 Modbus Plus Multiprotocol Network Gateway. The MBP-100 allows information to be transferred seamlessly among many different fieldbus networks with minimal configuration requirements. The MBP-100 provides one Modbus Plus port, one RS485 port, one RS232 port, and three common serial ports for direct connectivity to Toshiba 7-series, 9-series, 11-series or VF-nC1 Adjustable Speed Drives (ASDs).
MBP-100 Modbus Plus Multiprotocol Network Gateway User's Manual Part Number 10498-3.100-001 Printed in U.S.A. ©2008 Industrial Control Communications, Inc. All rights reserved Industrial Control Communications, Inc. reserves the right to make changes and improvements to its products without providing notice. Notice to Users INDUSTRIAL CONTROL COMMUNICATIONS, INC.’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE-SUPPORT DEVICES OR SYSTEMS.
Usage Precautions Operating Environment • Please use the gateway only when the ambient temperature of the environment into which the unit is installed is within the following specified temperature limits: Operation: -10 ∼ +50°C (+14 ∼ +122°F) -40 ∼ +85°C (-40 ∼ +185°F) Storage: • Avoid installation locations that may be subjected to large shocks or vibrations. Avoid installation locations that may be subjected to rapid changes in temperature or humidity.
TABLE OF CONTENTS 1. The Network Gateway Series Concept.......................................6 2. Mechanical Diagrams ...................................................................7 2.1 2.2 2.3 Enclosure ..............................................................................................7 Mounting Clip ........................................................................................8 External Interface ..............................................................................
13.1.3 Application Configuration ........................................................... 30 13.2 Invocation ........................................................................................... 33 13.3 Main Menu.......................................................................................... 34 13.3.1 View/Edit Points ......................................................................... 35 13.3.2 View/Edit Ports .........................................................................
1. The Network Gateway Series Concept The MBP-100 is a member of the ICC Network Gateway Series product family. Members of this family are designed to provide a uniform interface, configuration and application experience. This commonality reduces the user’s learning curve, reducing commissioning time while simplifying support. The MBP-100 provides simultaneous support for many different communication protocols, allowing complex interchanges of data among otherwise incompatible networks.
2. Mechanical Diagrams 2.
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Data Write LEDs ASD #3 ASD #2 ASD #1 Figure 5: Top View 10 ASD Link LEDs
3. Feature Summary Modbus Plus Port Standard DB9 connector. Supports both standard (MSTR) read and write as well as global data read and write instructions. Any internal data point has the option of being mapped to the gateway’s “get” or “put” global data. “Get” global data can be configured on a point-by-point basis to originate from any existing device on the network, providing for powerful and efficient peer-to-peer communication.
New network drivers are continuously being added, and can be downloaded for free from our web site. Text-Based Console Configuration Unit configuration is performed via a text-based console interface, available locally over the RS232 port via a standard PC terminal program such as Microsoft Windows HyperTerminal®.
In all cases, the unit can be easily unsnapped from the mounting clip to temporarily provide easier access to the chassis ground terminal or network connector.
4. Installing the Gateway The gateway’s installation procedure will vary slightly depending on the chosen mounting method and the networks that will be used. 4.1 RS-485 Network in Use Note that in order to power the unit when not connecting to Toshiba ASDs via the common serial ports, the optional 120VAC/9VDC power supply (ICC part number 10456) or a user-supplied power source meeting the requirements outlined in section 11 must also be installed. 1.
4.2 Toshiba ASD (Common Serial) Network in Use The gateway connects to each drive via the drive’s common serial (logic level) communication port, typically located on either the main drive control board (G7, S11), on the front of the drive enclosure under a small snap-on cover (A7, S9), on the right-hand side of the drive enclosure under a small snap-on cover (S7), or on the bottom side of the drive enclosure (VF-nC1).
4. Remove the drive’s front cover / open the drive’s cabinet door (refer to the appropriate drive manual for instructions how to do this). 5. The drive’s LCD panel (also called the “Electronic Operator Interface” or “EOI”) can communicate with the drive via either the RS485/RS232 channel (CNU1/CNU1A) or the common serial channel (CNU2/CNU2A). Because the gateway uses the common serial channel, the LCD panel must be configured to use the RS485/RS232 channel.
ICC or your local Toshiba representative for assistance if the problem persists. 4.2.2 Installation for S7, S9, S11, A7 and VF-nC1 ASDs 1. Mount the unit via the desired method (refer to page 12 for more information). 2. CAUTION! Verify that all input power sources to the drives to be connected have been turned OFF and are locked and tagged out. 3. DANGER! Wait at least 5 minutes for the drive’s electrolytic capacitors to discharge before proceeding to the next step.
9. Take a moment to verify that the gateway and all network cables have sufficient clearance from drives, motors, or power-carrying electrical wiring. 10. Turn the power sources to all connected drives ON, and verify that the drives function properly. If the drives do not appear to power up, or do not function properly, immediately turn power OFF. Repeat steps 2 and 3 to remove all power from the drives. Then, verify all connections.
5. RS485 Port Electrical Interfaces In order to ensure appropriate network conditions (signal voltage levels, etc.) when using the gateway’s RS485 port, some knowledge of the network interface circuitry is required. Refer to Figure 6 for a simplified network schematic of the RS485 interface circuitry. Note that the “Shield” terminal has no internal connection: its purpose is simply to provide a cable shield chaining location between devices.
6. Environmental Specifications Item Specification Operating Environment Indoors, less than 1000m above sea level, do not expose to direct sunlight or corrosive / explosive gasses Operating Temperature -10 ∼ +50°C (+14 ∼ +122°F) Storage Temperature -40 ∼ +85°C (-40 ∼ +185°F) Relative Humidity 20% ∼ 90% (without condensation) Vibration 2 5.9m/s {0.
7. Maintenance and Inspection Preventive maintenance and inspection is required to maintain the gateway in its optimal condition, and to ensure a long operational lifetime. Depending on usage and operating conditions, perform a periodic inspection once every three to six months. Before starting inspections, disconnect all power sources.
8. Storage and Warranty 8.1 Storage Observe the following points when the gateway is not used immediately after purchase or when it is not used for an extended period of time. • Avoid storing the unit in places that are hot or humid, or that contain large quantities of dust or metallic dust. Store the unit in a well-ventilated location. • When not using the unit for an extended period of time, apply power at least once every two years and confirm that it still functions properly. 8.
9. LED Indicators The gateway contains several different LED indicators, each of which conveys important information about the status of the unit and connected networks. These LEDs and their functions are summarized here. 9.1 Toshiba ASD Common Serial Port Indicators Each Toshiba ASD common serial port RJ45 connector contains two integrated green LEDs. Figure 8 indicates the functions of these LEDs.
10. Configuration Switches There are eight configuration DIP switches (marked “CONFIG”) located on the front side of the gateway. Switches #1 - #6 set the Modbus Plus station address of the gateway (refer to Table 1). Note that whenever the station addressing switches (#1 - #6) are changed, power must be cycled to the gateway to validate the change.
Switches #7 and #8 perform the following functions: Switch #7 .........RS232 port selection switch. When “OFF” at unit startup, the RS232 port will act as the serial console, regardless of the port’s configuration or protocol assignment (refer to section 13 for more information on the serial console). When “ON” at unit startup, the RS232 port carries whatever protocol (if any) was assigned to it at configuration time. Note that the state of this switch is only detected when the gateway boots up. Switch #8 .
12. Unit Configuration Concepts 12.1 Port and Protocol Configuration Each of the communication ports can be individually configured or enabled/disabled. It is important to note that with one exception, the ports function independently of one another, and can operate simultaneously. For example, a Modbus RTU slave request on the RS485 port and a Modbus Plus request can simultaneously access the same internal point.
The default timeout time in all cases is 0, which disables network timeout handling. When nonzero, timeout processing does not begin until after a valid network packet has been received by the unit on that port. When the timeout time is nonzero and a communication interruption is detected, the timeout enable selections for each point are inspected.
This concept may best be further explained by way of a representative scenario. For example, let’s assume that the gateway’s RS485A port has been designated to be a Modbus Master. Let’s further assume that the “Modbus Master” portion of point #5 indicates an “Address” value of 8 and “Register” value of 14, and that point #5’s “Source Port” selection is set to “RS485A”.
1. 2. 3. 4. 5. Access the serial console configuration interface via Hyperterminal or other text-based console program. Assign (or enable/disable) the desired protocols and their characteristics to the specific communication ports. Perform the desired per-protocol mapping and definition assignments for each point, including the name, timeout and “source port” assignments. Exit the serial console, which will prompt you to update the gateway’s internal configuration file and then reboot the unit.
13. Console Access 13.1 RS232 The console is accessible via an RS232 interface for direct connection to a computer’s serial (COM) port. This is performed by connecting the unit’s RS232 (MMI) port to the computer’s serial port via the included serial cable. 13.1.
Figure 10: HyperTerminal Properties…Connect To Figure 11: HyperTerminal Properties…Connect To…Configure 31
Figure 12: HyperTerminal Properties…Settings 32
13.2 Invocation The console provides standard access and editing methods for the various configuration items (ports, points and their associated attributes). It is important to note that whenever you modify the point database and are ready to restart the gateway (“exit”), you must save the database to the internal file system prior to restarting or your changes will be lost.
13.3 Main Menu The main menu is shown in Figure 14. All gateway configuration is performed by “drilling down” into progressively lower-level menus. Figure 14: Console Main Menu All navigation and data entry commands are input by simply entering the menu selection number to the right of the “>” symbol along with any required data fields at the console prompt. In Figure 14, for example, entering the menu selection number “1” (without the quotation marks) will bring up the View/Edit Points submenu.
13.3.1 View/Edit Points Main menu selection number 1 displays a screen which shows a summary of the current point configuration (see Figure 15). This screen only displays the point number and the point name: in order to access more detailed point information, menu selection number 1 “Edit/View a Point” must be entered with the additional argument of the targeted point’s number. The syntax used to edit/view point #1 is shown at the bottom of Figure 15.
Figure 16: Edit a Point • Edit Name: Menu selection number 1 allows you to change the point’s name. For example, the bottom of Figure 16 shows an example of changing point #1’s name to output_voltage. The point’s name is purely for user recognition of a point, and has no bearing upon communications functionality. To clear the point’s name field, just enter the menu selection (“1”) with no additional argument.
Toshiba Point Attributes Figure 17: Edit Toshiba Attributes • Edit Address: Menu selection 1 allows you to edit the network address of the Toshiba ASD that this point refers to. This address field is only used in conjunction with the Toshiba RS485 protocol: Toshiba common-serial port connections are point-to-point, and therefore do not require targeting a drive at a specific address. • Edit Parameter: Menu selection 2 allows you to edit the Toshiba ASD parameter that this point will access.
Mitsubishi Point Attributes Figure 18: Edit Mitsubishi Attributes • Edit Address: Menu selection 1 allows you to edit the network address of the Mitsubishi ASD that this point refers to. • Edit Parameter: Menu selection 2 allows you to edit the Mitsubishi ASD parameter that this point will access. Figure 18 shows an example of how to change the current setting of 1 to 1014.
Modbus Master Point Attributes Figure 19: Edit Modbus Master Attributes • Edit Address: Menu selection 1 allows you to edit the network address of the Modbus slave that this point refers to. • Edit Register: Menu selection 2 allows you to edit the Modbus holding register or input register that this point will access. The type of register accessed (holding or input) will be determined on the basis of the “Read FC” setting (see below).
Modbus Slave Point Attributes Figure 20: Edit Modbus Slave Attributes • Edit Register: Menu selection 1 allows you to assign a Modbus register (accessible as either a holding register or input register) to this point. Figure 20 shows an example of how to change the current setting of 7 to 8. Note that this Modbus register index is used whether accessing the point via Modbus RTU or Modbus Plus MSTR commands.
Modbus Plus Point Attributes Figure 21: Edit Modbus Plus Attributes • Edit Get Global Node: Menu selection 1 allows modification of the selected node on the network from which this point will consume (get) global data. This value is ignored if the “Get Global Offset” is “DISABLED”. • Edit Get Global Offset: Menu selection 2 allows modification of the offset within the Get Global Node’s data block that this point will consume (get) from.
Implementing Global Data As indicated above, three global data configuration items exist for each point in the point database: a “get” node, a “get” offset, and a “put” offset. If a given point is intended to be accessed only via standard MSTR write and read commands (MSTR functions 1 and 2, respectively), then both the “get” and “put” offsets should be set to “DISABLED”. Standard MSTR read and write commands can then be used to access the point by targeting its “Modbus Slave Register” assignment.
Table 2: Global Data Assignment Example (x=Don’t Care) Get Node 3 x 8 8 3 x x x x x x x Point # 1 2 3 4 5 6 7 8 9 10 11 12 Get Offset Put Offset Note 2 DISABLED 5 5 3 DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED 0 1 4 DISABLED 5 7 8 Get from node #3 No global data access Get from node #8 Get from node #8 Get from node #3 Put Put Put No global data access Put Put Put With the indicated global data assignments, we can get a logical overvie
13.3.2 View/Edit Ports Main menu selection number 2 displays a screen which shows a summary of the current port configuration (see Figure 25). This screen only displays the current protocol selected for each port: in order to access more detailed port information, select the menu number corresponding to the desired port. Menu selections 1-3 correspond to the Toshiba common serial ASD ports, and these contain no other port configuration other than enable/disable.
RS485/232 Port Configuration Figure 26: Edit Port Configuration • Edit Protocol Selection: Menu selection 1 allows you to change what serial protocol is running on the selected port. Note that not all ports run the same protocols. Figure 26 shows an example of changing the protocol selection on the RS485 port from Disabled to Modbus Slave. • Edit Baudrate: Menu selection 2 allows you to change the baudrate for the selected port.
13.3.3 Load Points Main menu selection number 3 allows the retrieval of a predefined configuration into working memory (see Figure 27). Loading one of these configurations overwrites the existing point configuration. Currently, entering submenu selection 1 returns the gateway’s configuration to its factory default state. Figure 27: Loading a Point File 13.3.
argument of the xmodem command indicates the mode, and must be set to either “/crc” for Xmodem CRC mode, or “/cs” for Xmodem checksum mode. As mentioned above, configuration files can be both downloaded and uploaded. The second argument in the xmodem command indicates the action to take, and must be set to either “/d” to download the configuration file from the unit, or “/u” to upload a configuration file to the unit. Figure 28 shows an example of initiating an Xmodem download in CRC mode.
Figure 29: HyperTerminal receive file dialog box When uploading a file, the procedure is similar to downloading. Enter “/u” instead of “/d” for the action parameter of the xmodem command. Once the xmodem upload command is entered, the user will have 30 seconds to click the “send” button ( ) on the tool bar in HyperTerminal and initiate the Xmodem upload transaction.
14. Protocol-Specific Information This section will discuss topics that are specific to each of the available network selections. 14.1 Modbus The gateway supports Modbus slave and master functionality via Modbus RTU. The slave implementations share common access methods, which is to say they support the same functions and reference the internal points via a common “Modbus Slave” register assignment.
• Because the transaction is handled locally within the gateway, write data checking is not available. For example, if a write is performed to a register with a data value that is out-of-range of the corresponding “source port” object, no Modbus exception will be immediately returned. However, the point will always reflect the “source port” status and object value.
For clarity, let’s use Equation 1 and Equation 2 in a calculation example. Say, for instance, that we are going to read coil #34. Using Equation 1, we can determine that coil #34 resides in register #3, as ⎣3.0625⎦ = ⎣3 r1⎦ = 3. Then, using Equation 2, we can determine that the bit within register #3 that coil #34 targets is (34-1)%16 = 1, as 33%16 = mod(2 r1) = 1. Therefore, reading coil #34 will return the value of register #3, bit #1.
• Note that various manufacturers will document their Modbus slave products in different ways. In particular, according to the Modbus specification, registers have two different indices at which they can be referenced: their “known as” value (which starts at number 1) and their “addressed as” value (which is always 1 less than the “known as” value).
14.2 Modbus Plus • Supported MSTR functions are indicated in Table 5. Table 5: Supported MSTR Functions Function Code Function 1 2 5 6 Write Registers Read Registers Write Global Data Read Global Data • Modbus Plus register assignments are common between the Modbus Plus and Modbus RTU Slave protocols.
14.3 Toshiba Common Serial ASD Protocol • The gateway can act as a Toshiba ASD master via its dedicated common serial (TTL) port connections. All Toshiba drives that include a common serial port are supported. • No configuration is necessary, as the gateway automatically adapts to the ASD’s configured characteristics. • The RS485 port and the ASD1 port of the gateway are internally shared, which means that they both cannot be active simultaneously.
that this may involve hardware configuration in addition to parameter changes. For example, G7/Q7/H7-series drives have duplex selection jumpers located on the drive’s control board near the communication ports. For these drives, both jumpers must be placed in the “HALF” position. Refer to Figure 31 for an example detailed view of correctly-positioned duplex selection jumpers.
• The RS485 port and the ASD1 port of the gateway are internally shared, which means that they both cannot be active simultaneously. Also, the RS485 port’s configuration has priority over that of the ASD1 port: if any protocol is assigned to the RS485 port, then the ASD1 port will be automatically disabled. Note, however, that the ASD2 and ASD3 ports will at all times operate independently of all other network ports. • All parameter writes use the drive’s RAM / EEPROM data write (“W”) command.
14.5 Mitsubishi ASD Protocol • The gateway acts as a Mitsubishi protocol master via its RS485 port. Adjustable speed drives such as the FR-A500/E500/F500 series and F700series that support the Mitsubishi protocol can be accessed. Also supported are MGI Technologies, Inc. M3000, M4000 and M5000-series drives that support the Mitsubishi protocol. • For 500-series drives, the gateway can connect to the ASD via either the PU (panel) connector, or via an optional FR-A5NR computer link board.
Connect as shown in Figure 35. Figure 34: EIA/TIA Wiring Standards RDA SDA SDB RDB A (TB:1) B (TB:2) Signal Ground (TB:3) Figure 35: PU Port Connections • For 700-series drives, the gateway can connect to the ASD via either the PU (panel) connector as indicated in Figure 35, or via the on-board RS485 terminals. Because both of these ports externally present a 4-wire RS485 network, connecting them to the gateway requires jumpering the network wires for 2-wire format (i.e.
A (TB:1) B (TB:2) Signal Ground (TB:3) Figure 36: 700-Series ASD Connections • Note that although the 700-series ASD also supports the Modbus RTU protocol, the initial ASD firmware did not support the Modbus RTU protocol in 2-wire format. Therefore, using the Mitsubishi protocol may be the only available method to communicate with the gateway (ASD parameter 549 must be “0”). Contact Mitsubishi Technical Support for more information.
on these parameters, please refer to the relevant Mitsubishi documentation.
14.6 Teco-Westinghouse ASDs The gateway can act as a Modbus RTU protocol master via its RS232 and RS485 ports, which allows connection to Modbus-capable Teco-Westinghouse ASDs. While it is possible to connect to any Teco-Westinghouse ASD that supports Modbus (either RS232 or RS485), this section will discuss in particular some important considerations to make note of when connecting to, and interacting with, the PA7300 (with installed PA-M card) and MA7200 ASDs via RS485. 14.6.
• The MA7200 Modbus manual indicates that control data registers (0000H..000FH) are read/write, but reading always returns 0. • All drive parameters may be read at any time, but only Cn parameters can be written while the inverter is in DRV mode. The inverter must be in PRG mode to write any other parameters. • The drive parameters that configure the RS-485 communication characteristics (baud rate, etc.) do not take effect until the drive is reset.
“known as” register value of 37, which can then be entered in the Modbus master “register” assignment of a point on the gateway.
15. Modicon PLC Programming Examples This section of the manual is being provided solely as a brief overview of the general ladder logic program architecture that can be used to interface with the MBP-100 over a Modbus Plus network. For the most detailed information available, the appropriate Modicon PLC Programming Manual should always be consulted. 15.
15.1.1 MSTR Parameters • The number in the top portion of the MSTR block is the address of the first of six registers in the Control Block, and is generally configured as indicated in Table 7. Table 7: MSTR Control Block Format Address Description 4x Identifies which MSTR function is to be executed. The MBP-100 supports read, write, global read, and global write.
15.1.2 MSTR Inputs and Outputs Figure 38 indicates the inputs and outputs associated with MSTR instructions. INPUTS Activ ate MSTR Instruction OUTPUTS MSTR Instruction Instruction Activ e 40050 (Control Block) Terminate MS TR Instruction 40100 Instruction End - Error (Data Area) 100 (# data registers) Instruction End - No Error Figure 38: MSTR Inputs and Outputs 15.2 MSTR Function Error Codes Table 8 indicates the error codes that may be output in the “4x+1” location of the MSTR control block.
Address 40050 40051 40052 40053 40054 40055 2. Description MSTR function (read) Error code Number of consecutive registers to read Starting register Destination node address Master node address Register Value 2 Read Only 2 1 2 1 Set the middle portion of the MSTR instruction to 40100. This will be the starting address of the MSTR Data Area. This is the location that will contain the read data returned from the MSTR transaction.
Address 40200 40201 40202 40203 Value Value to write to register 1 @ network address 32 Value to write to register 2 @ network address 32 Value to write to register 3 @ network address 32 Value to write to register 4 @ network address 32 4. In this case, we are accessing four registers, so set the bottom portion of the MSTR instruction (“number of registers”) to 4. In the case of MSTR writes, this number cannot be greater than 100 by definition. 5.
4. In this case, we are accessing 32 words of global data, so set the bottom portion of the MSTR instruction (“number of registers”) to 32. In the case of MSTR global reads, this number cannot exceed 32 by definition. 5. Initiate the global read command by closing internal relay 1. The data response will be seen in the MSTR Data Area (starting at register 40300). 15.
16. Firmware Updates The gateway’s embedded firmware resides in flash memory that can be updated in the field. Firmware updates may be released for a variety of reasons, such as custom firmware implementations, firmware improvements and added functionality as a result of user requests. ICC is continually striving to enhance the functionality and flexibility of our products, and we therefore periodically release new embedded firmware to achieve these goals and meet customer requests.
download firmware to its flash memory: all other application functions (such as communications, console access etc.) will be disabled. 16.3 Using the RFU Utility Support for downloading new application firmware to the gateway is provided by the free Rabbit Field Utility (RFU), which is a 32-bit application that runs on Microsoft Windows platforms. The RFU utility can be downloaded from ICC’s website at http://www.iccdesigns.com.
The Communications Options window shown in Figure 40 then appears. Confirm that the settings are as shown, with the possible exception of the “Comm Port” settings, which depends on the COM port you are using. Click “OK” when complete. Figure 40: Communications Options Window Next, select the “Setup…File Locations” menu item from the main screen. The “Choose File Locations” window shown in Figure 41 then appears. Confirm that the correct paths to the referenced files are entered.
16.3.3 Transmitting Firmware Files When a board support package (BSP) has been downloaded and unzipped, the flash firmware file will be the one with “.BIN” as its file name extension. Once the RFU utility has been configured, the flash firmware files can be downloaded to the gateway by two different methods. The simplest way is to drag the application firmware .BIN file’s icon and drop it onto the RFU utility’s main screen. This will automatically initiate the download process.
16.4 Wrap-Up Once downloading is complete, close the RFU utility, move CONFIG switch #8 back to the “OFF” (up) position to exit “firmware download” mode, and cycle power momentarily to the unit by either disconnecting the auxiliary power supply and/or powering down all connected drives or momentarily removing all drive communication cables from the unit. When the unit powers up again, it will be running the new application firmware.
NETWORK GATEWAY SERIES ICC INDUSTRIAL CONTROL COMMUNICATIONS, INC. ICC INDUSTRIAL CONTROL COMMUNICATIONS, INC. Madison Office 1600 Aspen Commons, Suite 210 Middleton, WI USA 53562-4720 Tel: [608] 831-1255 Fax: [608] 831-2045 http://www.iccdesigns.com MBP-100 Houston Office 12300 Dundee Court, Suite 212 Cypress, TX USA 77429-8364 MODBUS PLUS MULTIPROTOCOL NETWORK GATEWAY Printed in U.S.A August 2008 ICC #10498-3.
