Schneider Automation Gmbh

Scorpion Controls, Inc.

Andrew G Swales

Allan Tanzman

A Dean Papadopoulos

David T Lindner

Richard A Baker, Jr

Richard H Breinlinger

Rodolfo G Belliardi

Ronald H Naismith

Orlando P Metcalf

Dennis J Dube

Merrill W Harriman

James W McGlaughlin, Iii

Cynthia Davies

Denis W Dube'

James V Mc Glaughlin Iii

A Dean Papdopoulos

A communications adapter is provided for interfacing between a master device and an I/O device (body) having an output and/or an input. In the case of the I/O body having an output, the adapter has a TCP port for coupling to the master device via a transmission path for receiving a request message. The adapter also has a connector for operable coupling to the I/O device for receiving the output of the I/O device. The adapter further has an interface circuit operably connected to the TCP port and the connector for transmitting a response message over the transmission path in response to the request message, the response message correlating to the output received from the I/O device. The request message and the response message is limited to a length that is less than a TCP transaction length and/or a maximum transmission unit limit, or both, depending on the embodiment of the present invention.

Messaging application layer over ethernet to transport layer (TCP) communications method and apparatus for a modular terminal input/output system

The present invention is for automatic reconfiguration of industrial networked devices. More particularly, the system described herein facilitates use of TCP/IP networks, such as Ethernet, as an alternative for industrial fieldbus or device buses by removing the need to perform significant reconfiguration of devices such as I/O modules, sensors, or transducers under field replacement situations. The present invention uses a monitor agent to track the IP and MAC addresses of networked devices as well as port information. If a device fails, maintenance personnel make an in-field replacement of the failed device and the monitor agent automatically reassigns the IP address to the replacement device.

Automatic determination of correct IP address for network-connected devices

A method for adapting a computer-to-computer communication protocol, and especially TCP/IP, or any protocol implemented in a general purpose off-the-shelf network like Ethernet, for use in providing communication needed in an industrial control system, and especially an industrial control system using a programmable logic controller (PLC), where there is frequent communication between the PLC and control or monitoring elements, the method aimed at allowing the PLC to perform scanning of its ladder logic at a rate adequate for effective industrial control. The method includes making permanent-type TCP connections between the PLC and a control element or a monitoring element, use of a protocol for communication with a control or monitoring element in which both a read register and a write register instruction is included in a single communication transaction, such as a MODBUS command, and tuning communication between the PLC and a control element or a monitoring element.

Method for adapting a computer-to-computer communication protocol for use in an industrial control system

An interface allows for the transfer of real time control data with guaranteed delivery times between devices on a general purpose network and an industrial control system. A proxy server takes the role of a TCP/IP router and is configured to control the rate at which messages are forwarded from the non-real time to the real time portion of the network, keeping the loading of the real time portion stable regardless of the external non-real-time communication demand. Real time data is preconfigured and exchanged in a regular sequence, with the cyclic update period known. The length of any communication message necessary to transmit this information, plus any sequencing and acknowledgment overhead, is calculated in advance and aggregated. Each device with authority to transmit on the shared medium is given a time budget, calculated so that the total transmission quantity in unit time is deliberately limited to some fraction of the maximum transmission capability of the network. All communication from devices whose traffic loadings cannot be so controlled is arranged to pass through the proxy device in order to gain access to the deterministic network, and the proxy enforces the budget limits by introducing deliberate delays to the request messages if necessary.

Apparatus for controlling internetwork communications

A programmable logic controller for use as part of an industrial control system or as part of an automated system and a corresponding method, the controller including an interface to the Internet, and including a web server allowing a remote computer to access web pages maintained by the controller providing information relevant to the control function of the controller such as control sensor readings and, optionally, information about the status of the control system. The web server is implemented as part of the controller in such a way that the controller scan rate (the rate at which the ladder logic for all associated control system devices is repeated) is unaffected by execution of the web server.

PLC executive with integrated web server

A communications adapter and method are provided for interfacing between a master device and an I/O device (body) having an output and/or an input. In the case of the I/O body having an output, the adapter has a TCP port for coupling to the master device via a transmission path for receiving a request message. The adapter also has a connector for operable coupling to the I/O device for receiving the output of the I/O device. The adapter further has an interface circuit operably connected to the TCP port and the connector for transmitting a response message over the transmission path in response to the request message, the response message correlating to the output received from the I/O device. The request message and the response message is limited to a length that is less than a TCP transaction length and/or a maximum transmission unit limit, or both, depending on the embodiment of the present invention.

A bridge is disclosed for providing a connection between a MODBUS Plus network and an Ethernet network. The bridge includes a MODBUS circuit board, an Ethernet circuit board, and a CPU. The MODBUS circuit board is operably coupled to the local area network for receiving a message from an originating node having a five-byte routing path field. The CPU is operably connected to the circuit board for extracting a table location in response to a third byte within the routing path field. The Ethernet circuit board is operably connected to the CPU and the Ethernet network for forwarding the message to an IP destination in response to the table location.

MODBUS plus ethernet bridge

System for a modular terminal input/output interface for communicating messaging application layer over encoded ethernet to transport layer

A control system includes an Internet web interface to a network of at least one programmable logic control system running an application program for controlling output devices in response to status of input devices. The Web interface runs Web pages from an Ethernet board coupled directly to the PLC back plane and includes an HTTP protocol interpreter, a PLC back plane driver, a TCP/IP stack, and an Ethernet board kernel. The Web interface provides access to the PLC back plane by a user at a remote location through the Internet. The interface translates the industry standard Ethernet, TCP/IP and HTTP protocols used on the Internet into data recognizable to the PLC. Using this interface, the user can retrieve all pertinent data regarding the operation of the programmable logic controller system.

Growing community of inventors

Windham, NH, United States of America

Andrew G Swales