LonWorks Helps Get Semiconductor System 'Pumped'
BUS OF THE MONTH: LonWorks
..Semiconductor manufacturers are increasing requests for vacuum pumps, used for chip fabrication, with 'smart' facilities such as monitoring key pump parameters, remote control, and data logging. Edwards High Vacuum International (Eastbourne, U.K.) has introduced a pump system that features controls based on LonWorks. The control system provides monitoring of key pump parameters, remote location of interface devices, and the ability to monitor up to 400 sets from one or more computers. LonWorks has reduced customization costs, made field upgrades easier, and improved interfaces with other process equipment.
ventional microcontroller or by means of a programmable logic controller (PLC). However, several other market needs were more difficult to engineer using conventional electronics.
Flexibility a must
..One of the overriding requirements for the new pump control system was to maintain mechanical compatibility with the existing range of pumps. The compatibility issue arose because any new control system must fit within the existing pump case, or must be mounted externally to the pump. The company wanted to avoid external mounting because of the added expense.
trol via serial or parallel interfaces and data output to a computer system were also needed on many applications.
le cost. A control network also resolved the interfacing issue most elegantly in that each interface device could function as a separate network node.
than at regular intervals. This way network traffic is kept to a minimum, but all significant information is still transmitted. Each sensor holds its setpoint and configuration information locally in EEPROM. The setpoint store can be updated locally by means of the display unit, or remotely from a computer. The use of a computer for updating setpoints is especially useful because a complete set can be held in a file and downloaded as a single entity. The motor on/off control object accepts input from control devices, such as the display unit, act on sensor data packets received that indicate avalue that is far outside its normal range.
e and self-contained entity, and would connect to the existing data network. In a centralized architecture, any new sensor that needed to be added would probably require a new controller as well.
hardware facilities are accessible from the network, hardware test operations are accomplished automatically by running a test program from a computer.
LonWorks Helps Web Industry Avoid Tangles
..Horton Inc. in Minneapolis, Minn., is a manufacturer of clutches, brakes, and other electronic web handling products used with brakes and clutches on web handling machines (web materials include paper, film, foils, nonwovens, and textiles). In recent years, the company noticed an increase in web handling companies' requirements for networks with more flexible structures. Horton concluded that the benefits of a flexibly structured network were: reduced wiring cost; reduced maintenance cost; reduced labor to monitor; more user-friendly human-machine interface; and better performance including quicker set up, changeover, and less wasted material.
d the system, or upgrade performance by simply switching components in the network. Horton felt the ideal solution was an open-architecture network that would enable users to integrate their products and other vendors' products into a network, and enable users to bridge to existing PLC networks. Thecompany decided to apply LonWorks technology to its web control products based on a number of benefits:
Every node of a LonWorks network has intelligence. The control function is carried out by distributed nodes instead of a central unit. This ensures faster, more accurate control.
Two-wire network connections make it simple to connect nodes to a network.
An open architecture provides customers with choices to integrate, update, and expand a network.
LonWorks provides a gateway to multiple PLC systems.
LonWorks Network Services (LNS) tools are available to aid in developing Windows-based user interfaces
LonWorks Interface Promotes Open Connectivity
North Andover, Mass.-- The Quantum LonWorks interface provides network functionality ranging from individual device connections to intelligent subsystems, stand-alone dedicated controllers, and computers. It supports LonWorks by means of its NOL option module, which is available on three different media: FTT-10A, TPT/XF-78, and TPT/XF-1250. Multiple modules may be present in the same Quantum controller for flexible architecture choices. The Quantum module conforms to the requirements of the LonMark interoperability Guidelines.
LNS (LonWorks Network Services) Toolkit Eases Programming
Mundelein, Ill.-- The LNS toolkit for G and LabWindows/CVI allows programmers to easily access and define node properties, read and write network variables, read and write to or from node memory, and send explicit messages to nodes. The LNS Toolkit will work with LabView and will operate in Windows 95 or NT.
Alliance Technologies Group
Versatile Controller for Networking
Fremont, Calif.-- The Netmotion 300 is an advanced programmable controller for distributed and/or centralized networks. This controller consists of a Master Module and five Slave Modules: serial communication, servo motor control, stepper motor control, digital I/O, and analog I/O. Each controller's Master Module can be wired simply, with up to four Slave Modules connected in a parallel bus, and up to 16 Slave Modules connected in a twisted pair line. Up to 16 subnetworks (Master and Slave Modules) can be joined together into one cluster and up to eight clusters can be joined into one large network. One small task on a plant floor could be controlled from one PC or stand alone without a PC.
Netmotion Network Automation
Process Automation Controller Continues Family Tradition
Spring House, Pa.-- The model 353 is the next in line of the Model 352 product family of controllers from Moore Products. The 353 is a stand-alone microprocessor-based industrial controller designed for use in a broad range of process applications. It can serve as a single or multiloop controller with complete control and logic functions for a small unit batch or continuing process. The 353's fieldbus and networking options enable it to function as an integral element in a plant control/information system.
New Electronic Controls for Actuator
Houston, Tex.-- The ICON (Intelligent Control Open Network) electric actuator incorporates a new nonintrusive electronic controls package. It offers a nonproprietary, two-wire LonWorks option for remote control, monitoring, and historical reporting. The ICON is a smart valve actuator used for automating quarter-turn valves with up to 3.5 million lb-in. of torque, and multi-turn valves with up to 35,000 lb-ft of torque in weather proof or explosion proof applications.
Keystone International Inc.
LonWorks Interface for PC/104 Platform
Phoenix, Ariz.-- The PC104-LTNI Lontalk Network Interface board provides an interface between an industry standard PC/104 platform and a LonWorks distributed control network. The PC104-LTNI uses the Microprocessor Interface Program-Dual Port System (MIP-DPS) to create what the company claims is the highest performance LonWorks interface available for PC/104 embedded modular computers. It supports standard LonWorks media types including twisted pair, free topology, and RS-485. Engenuity Systems
LonWorks Module for Smaller Systems
Brown Deer, Wis.-- LON-bus module was designed for smaller systems with fewer I/O functions. With this new module, the network intelligence is integrated into each module. LON-bus modules allow the coupling of digital, analog, or serial communication devices, including diagnostic functions and have their own 'controller' or 'adapter.' The application can be loaded into any module. For communication to LonWorks, the connector is provided with a transceiver which depends upon the transfer medium for communication.
LonWorks: A Brief Overview
..LonWorks by definition is a network comprised of intelligent devices (actuators, sensors, operator interfaces, controllers) that communicate using a common, seven-layered protocol over one or more media. Its technology was developed by Echelon (Palo Alto, Calif.) to address a wide range of applications. Companies are attracted by the protocol which runs on the Neuron chip from Motorola or Toshiba. Code is available, allowing LonWorks to port to other silicon solutions. The versatility of the protocol allows companies to use Lonworks as a device, sensor, or fieldbus.
interoperable tools, Windows 95 and NT HMIs, component software with ActiveX objects, local and remote network access, and seamless connectivity to the Internet.
nly used to replace PLCs and complex wiring harnesses, the availability of third-party, off-the-shelf products is growing.
ug and play fashion.
Other LonWorks Industrial applications
Agriculture--harvesters, feeding stations, others
Automotive manufacture--parts pull, testing, paint spraying
Electropneumatic braking on trains
IC manufacture--gas distribution and tools
Petrochemicals--pumping, refining, gas stations
Power generation and distribution
Pulp and paper
Water and wastewater treatment