PROSOFT MVI56-MCMR Communication Module for Remote Chassis

PROSOFT MVI56-MCMR Communication Module for Remote  Chassis

MVI56-MCMR

The MVI56 Modbus Master/Slave Communication Module with  Reduced Data Block allows ControlLogix processors to interface  easily with other Modbus protocol compatible devices.

Compatible devices include not only Modicon PLCs (which all  support the Modbus protocol) but also a wide assortment of end  devices.

This module uses a small I/O data area for data transfer between the  module and the ControlLogix processor, making it ideal for  ControlNet or Ethernet applications with the module in a remote rack.

Applications using the Modbus Communication Module  can be found in many industrial sectors, including:

• Foreign device data concentrator  

• Pipelines and offshore platforms  

• Food processing  

• Mining  

• Pulp and paper  

• SCADA communications

Features and Benefits

The MVI56 Modbus Master/Slave Communications module with  reduced data block is designed to allow ControlLogix processors to  interface easily with Modbus protocol-compatible devices and hosts.  

The module acts as an input/output module between the Modbus  network and the ControlLogix processor. The data transfer from the  processor is asynchronous from the actions on the Modbus network.  A 5000-word register space in the module exchanges data between  the processor and the Modbus network.

Many host SCADA applications support the Modbus protocol, while  devices commonly supporting the protocol include several PLCs, as  well as many other third party devices in the marketplace. (For a  partial list of devices that speak Modbus, please visit the ProSoft  Tested section of the ProSoft Technology web site).

General Specifications

• Single Slot - ControlLogix backplane compatible  

• Designed especially for remote rack implementations  

• The module is recognized as an Input/Output module and has  access to processor memory for data transfer  

• Ladder Logic is used for data transfer between module and  processor. Sample Ladder File included  

• Configuration data obtained from configuration file downloaded  to module. Sample configuration file included

Slave Specifications

A port configured as a Modbus slave permits a remote master to  interact with all data contained in the module. This data can be  derived from other Modbus slave devices on the network, through a  master port, or from the ControlLogix processor. The MVI56-MCMR  module accepts Modbus function code commands of 1, 2, 3, 4, 5, 6,  8, 15, 16, 17, 22 and 23 from an attached Modbus master unit.

Master Specifications

A port configured as a virtual Modbus master device on the MVI56- MCMR module actively issues Modbus commands to other nodes on  the Modbus network. One hundred (100) commands are supported  on each port. Additionally, the master ports have an optimized polling  characteristic that polls slaves with communication problems less  frequently. The ControlLogix processor can be programmed to  control the activity on the port by actively selecting commands from  the command list to execute or issuing commands directly from the  ladder logic.

Functional Specifications

The MVI56-MCMR transmits smaller data packets than the MVI56- MCM, which makes it ideal for remote rack or where bandwidth is  limited

• 40 word data blocks (scheduled)  

• Status is passed by request using the MSG instruction  

• Pass-through not supported  

• Special functions (command control, event commands, status,  etc.) are supported by message transfer (unscheduled) using  the MSG instruction  

Some of the general specifications include:

• Support for the storage and transfer of up to 5000 registers  to/from the ControlLogix processor's data files  

• Module memory usage that is completely user definable  

• Two ports to emulate any combination of Modbus master or  slave device  

• Supports Enron version of Modbus protocol for floating point  data transactions