RSLinx

RSLinx Classic is an inclusive communication server which provides plant-floor device connectivity for a wide variety of Rockwell Software applications such as

• RSLogix 5/500/5000
• RSView32
• FactoryTalk View Site Edition
• FactoryTalk Transaction Manager

Besides, numerous open interfaces are provided for third-party HMI, data collection and analysis packages, and custom client-application software. RSLinx Classic is capable enough to support multiple software applications at the same time, communicating to a range of devices on many different networks.
RSLinx Classic 2.x is now associated to RSLinx Enterprise, a new product that provides supreme connectivity to Logix processors. RSLinx Enterprise provides data services for distributed FactoryTalk View Site Edition products, FactoryTalk Transaction Manager, FactoryTalk Historian, and FactoryTalk Metrics applications.
One can communicate from anywhere to anywhere using RSLinx Classic. RSLinx is available in multiple packages to meet the demand for a variety of cost and functionality requirements.

RSLinx Benefits

No Parity

Parity checking is also used in communication between modems. Here, parity checking can be selected to be even (a successful transmission will form an even number) or odd. Users may also select no parity, meaning that the modems will not transmit or check a parity bit. When no parity is selected (or defaulted), it's assumed that there are other forms of checking that will detect any errors in transmission. No parity also usually means that the parity bit can be used for data, speeding up transmission. In modem-to-modem communication, the type of parity is coordinated by the sending and receiving modems before the transmission takes place. Specifically, the Peripheral Component Interconnect bus and the I/O bus controller use the odd parity method of error checking.

Parity Limitations

Parity Checking

It is also known as Vertical Redundancy Check (VRC). It is a method of adding a parity bit to a data stream to check that data for any errors. It is an elementary method of detecting simple, single-bit errors in a memory system. It requires the use of parity memory, which provides an extra bit for every byte stored. This extra bit is used to store information to allow error detection. Parity checking on newer systems normally requires the appropriate BIOS setting to be enabled. ECC-only modules cannot be used in straight parity-checking mode.

Modbus to BACnet Protocol Converters

Checksum Files

A checksum file is a reasonably small file which contains the checksum values of other files. There are many formats of checksum files, frequently proprietary or closed. However there are also numerous open and widely supported formats. Major three formats include:

1. Simple File Verification (SFV): In the binary newsgroups and file-sharing networks SFV is a well known format. In this format, CRC32 algorithm is used and the file structure supposes ambiguity. Use of this format is generally not recommended.
2. MD5SUM: This format is mostly known in open systems world. It makes use of more secure and reliable MD5 algorithm and has more convenient structure of file. The Advanced Checksum Verifier utility support both formats, but the use of MD5SUM format is strongly recommended.
3. Alternative or BSD checksum format: This is more advanced format which allows using any checksum calculation algorithm. Unfortunately Advanced Checksum Verifier does not support currently this format. 

System Integrator

File Checksums

A checksum (also known as hash sum) is a fixed size value which is computed from an arbitrary block of digital data for the purpose of detecting accidental errors that may have been introduced during its transmission or storage. It basically allows us to check the validity of something. Usually, checksums are used in data transmission contexts to detect if the data has been transmitted successfully. The integrity of the data can be checked at any time later on, by recomputing the checksum and comparing it with the stored one. If the checksums do not match, the data was certainly altered, either intentionally or unintentionally.

RSView32 Active Display System

It is a true client/server application that adds on to and extends the reach of our RSView32 HMI software. By means of RSView32 Active Display System, we can view and control our RSView32 projects from remote locations.

RSView32 Web Server

It allows anyone with a valid RSView32 user account to access snapshot views of graphic displays, tags, and alarms through any standard web browser.

Add-on Architecture

Add-on architecture (AOA) technology expands RSView32's functionality by integrating new software components directly into RSView32. We can customize RSView32's feature set by installing only those components which we require. RSView32 includes the following AOA components that we can install separately at no extra cost:

• RSView32 Messenger: It provides powerful alarm annunciation, paging, and messaging tools.
• RSView32 TrendX: It monitors real-time data and provides historical trending from RSView32 data logs.
• RSView32 SPC: It offers integrated & real-time Statistical Process Control.
• RSView32 RecipePro: It enhances RSView32 recipe management and control.
• RSLadder: It displays ladder logic for the Allen-Bradley SLC 500 and PLC-5 families of processors. 

RSLogix 5 Benefits 1

Following are the major benefits offered by RSLogix 5:

Ladder

Via RSLogix 5 all project information can be consolidated and displayed as a Project Tree with "Point-and-Click" accessibility. Numerous rungs are edited simultaneously and program using symbols that we have not yet assigned addresses to using the Program Editor. Besides, errors get corrected at our own convenience using the Project Verifier.

Cross-Reference Information

RSLogix 5 enables us to move to any rung or instruction we require by clicking on the cross-referenced item using the Online Cross-Reference. Cross-reference information can be viewed simultaneously with our control program online or on a report.

Drag-and-Drop Editing

By means of RSLogix 5 one can:

1. Add addresses to instructions by dragging them from the Data Table Monitor, Database Files, or the Address/Symbols Picker to the desired instruction.
2. Rapidly move instructions within a project or from one project to another.
3. Move data table elements from one data file to another. 

Absorptance

Absorptance also referred to as absorption factor is the property of a body which determines the fraction of the incident radiation or sound flux absorbed or absorbable by the body. It is defined as the ratio of the luminous or radiant flux absorbed by a body to the flux falling on it. It is usually represented by the Greek letter α (alpha). It was previously known as absorptivity. In the case of a blackbody, absorptance i.e. α = 1. Standard unit of absorptance is percent (%) or a factor between 0 and 1.

Compact Fluorescent Lamps - Advantages & Disadvantages

 Advantages

Compact fluorescents offer following advantages over incandescent light bulbs:

• Lower power consumption i.e. CFL consumes 1/4 the energy, and produce 90% less heat as compared to incandescent lamps.
• Longer lifetime (last up to 10 times longer than incandescent lights)
• Produce more light

Disadvantages

• Longer starts
• More expensive than incandescent lamps owing to their higher initial cost.
• CFLs are physically larger than incandescent lamps which may make them difficult to use in some light fixtures.
• Fluorescent tubes contain a microscopic amount of mercury. It is such a small amount that disposal is not generally regulated as with full size fluorescents. Hence we should use caution to avoid crushing the tubes, and dispose of them safely. 

Types of Compact Fluorescent

Compact fluorescent lamp

Compact fluorescent lamps are smaller versions of standard fluorescent lamps. They consume between 5 to 27 watts, and have a brightness and color interpretation that is equivalent to incandescent lights. Unlike standard fluorescents, they can directly replace standard incandescent bulbs. Compact fluorescent lamps (CFLs) combine the energy efficiency of fluorescent lighting with the convenience and popularity of incandescent fixtures.

Working of CFL

Compact fluorescent lamps work to a great extent like standard fluorescent lamps. They consist of two parts:

1. A gas-filled tube
2. Magnetic or Electronic ballast

The gas in the tube glows with ultraviolet light when electricity from the ballast flows through it. This in turn excites a white phosphor coating on the inside of the tube, which emits visible light throughout the surface of the tube. Compact fluorescent lamps with magnetic ballasts flicker slightly when they start. Besides, they are heavier than electronic ballasts. Electronic ballasts are more expensive than magnetic ballasts. However, they are more efficient especially at low temperatures. Most currently available CFLs have electronic ballasts.

Compact Fluorescent Lamp Main Features

by Chipkin Automation Systems

Halogen Cycle

Halogen lamp is filled with the same inert gases as incandescent lamps mixed with small amounts of a halogen gas (generally less than 1% bromine). The halogen chemically reacts with the tungsten deposit to produce tungsten halides. When the tungsten halide reaches the filament, the intense heat of the filament causes the halide to break down, releasing tungsten back to the filament. This process is known as the tungsten-halogen cycle and it maintains a constant light output over the life of the lamp. To make this halogen cycle to work following are the basic requirements:

• The bulb surface must be very hot otherwise the halogen may not effectively vaporize or fail to adequately react with condensed tungsten.
• The bulb needs to be smaller and made of either quartz or a high-strength, heat-resistant grade of glass known as aluminosilicate.

Since the bulb is small and reasonably strong due to its thicker walls, it can be filled with gas to a higher than normal pressure. This slows down the evaporation of the tungsten from the filament, increasing the life of the lamp. The higher pressure and better fill gases can extend the life of the bulb and permit a higher filament temperature which results in better efficiency.

Arc Lamp

It is a type of electric-discharge lamp in which an electric current flows between electrodes through a gas or vapor. In nearly every arc lamp, the light results from the luminescence of the gas. However in carbon arc lamp, the light is produced by the incandescence of one or both electrodes. The color of the arc depends upon the electrode material and the surrounding atmosphere. Majority of the lamps have a negative resistance characteristic so that the resistance decreases after the arc has been struck. Consequently some form of current-limiting device is required in the electric circuit. Arc Lamp Features.

Bacnet Protocol Converters

Ballast Factor (BF)

It is the measured ability of particular ballast to produce light from the lamps it powers. It is derived by dividing the lumen output of a particular lamp/ballast combination by the lumen output of the same lamps on reference ballast. Hence, Ballast factor is the ratio of the luminous output of a lamp when operated on ballast to its luminous output when operated under standardized rating conditions. In other words, it is the percentage of rated lumens from the same lamp using commercial ballast as compared to ANSI reference ballast. Ballast factor is not a measure of energy efficiency. For example, a ballast factor of .96 means the commercial ballast produces 96% of light produced by ANSI reference ballast operating the same lamp. The ballast factor can be referred to in the catalogs from fluorescent or HID ballast manufacturers.

Electronic Ballast

Fluorescent lighting

Fluorescent lighting is a popular and efficient lighting system used globally. It is most commonly found in commercial facilities. Fluorescent lamps emit extremely bright glow without getting blistering hot like an ordinary light bulb. They are more efficient as compared to incandescent lamps. Fluorescent lamps and fixtures are certainly more expensive to install than incandescent lighting, but they are significantly cheaper to operate. Besides, the lamps last far longer than incandescent lamps, making the long term cost-of-operation for fluorescent lighting far less than incandescent lighting. Because of their versatility, fluorescent lamps are available in numerous sizes, types, shapes, colors and light intensity. Some are designed to operate in cold locations, while others generate large amounts of light at the expense of service life.
All fluorescent lamps grow dimmer with age, and they may even begin to flicker or flash on and off. These are warning signals, and we should make the necessary repairs as soon as we notice any change in the lamp's normal performance. A dim tube frequently requires replacement, and failure to replace it can strain other parts of the fixture. Also, repeated flickering or flashing will wear out the starter, causing the insulation at the starter to deteriorate.

Basic Concepts

Blackbody

A black body is a theoretical object that absorbs 100% of the radiation that strikes it. Consequently it reflects no radiation and appears perfectly black. However, in practice no material has been found to absorb all incoming radiation, other than carbon in its graphite form since it absorbs all but about 3%.
Black body is also an ideal emitter of radiation. At a particular temperature it would emit the maximum amount of energy possible for that temperature. This value is referred to as the black body radiation. The maximum wavelength emitted by a black body radiator is infinite. It also emits a definite amount of energy at each wavelength for a particular temperature, hence standard black body radiation curves can be drawn for each temperature, showing the energy radiated at each wavelength. All objects emit radiation above absolute zero.

Blackbody Example

RSEnergyMetrix Scalability, Connectivity, Configuration

Scalability

RSEnergyMetrix has the scalability to add additional software features at the same time maintaining our initial investments.

Connectivity

RSEnergyMetrix makes connectivity to devices simple by using RSLinx or OPC. It Supports connectivity to Allen-Bradley Power monitors, EEMs, and PLCs via RSLinx RS232, RS-485, Ethernet, DeviceNet, RIO pass-thru, optical, and modem whereas connectivity to third-party devices is supported via OPC.

Configuration

RSEnergyMetrix provides easy and flexible configuration from our Web browser. It can configure

• Allen-Bradley Power monitors
• Water, air, gas, electric, steam, or other energy meters
• Manual meters for manual data entry (useful for entering in production data)
• Groups and tree structure to simulate organization or department schema

Besides, it allocates meters to groups for cost allocation and creates rate schedules to reproduce energy bills

RSEnergyMetrix Uses

FactoryTalk Metrics Benefits

FactoryTalk Metrics assist us refine, streamline, and prioritize our process improvement initiatives, resulting in reduced downtime, decreased cycle time, and increased overall production. FactoryTalk Metrics endows with following benefits:

1. Increase capacity: More product, revenue, and profit in the same amount of time
2. Decrease manufacturing costs: Less overtime, reduced labor costs, lower per-unit costs
3. Defer capital expenditures: Make your current equipment produce more
4. Decrease overhead costs: Save time in collecting data and preparing reports
5. Empower continuous improvement: Automatic data collection more focused on improvement 

Emonitor Condition Monitoring Capabilities

Emonitor includes the widest range of data harvesting tools available today. Via these tools, Emonitor can easily fulfill following requirements:

• Inspection Data Logging
• Process Data Logging
• Vibration Data Collectors
• Oil Analysis Instrumentation
• Oil Analysis Laboratories File Import
• Calculated Measurements

Emonitor Asset Data Integration Functions

Emonitor Main features I

Emonitor supports the latest generation of the Enpac Windows CE-based data collectors. It also supports the Datapac family of collectors, along with previous generation Entek products and many data collectors from other suppliers.

Emonitor can also support streams of data coming in from a variety of permanently installed sensors or systems, including Surveillance Vibration Data Collection, Protection Data Collection, Process Historian Gateways and OPC (OLE for Process Control).

Besides these data sources, Emonitor can manage images and ActiveX data objects which is mainly valuable for infrared thermography data, magnified images of oil samples, or other condition indicating technologies.  

Emonitor Main features II

EIA-485 Applications

EIA-485 is used:

1. In an extensive range of computer and automation systems. In a computer system, SCSI-2 and SCSI-3 may use this specification to implement the physical layer for data transmission between a controller and a disk drive.
   
2. For low-speed data communications in commercial aircraft cabins vehicle bus where it requires minimal wiring, and can share the wiring among several seats, resulting in reduced weight.
   
3. As the physical layer underlying many standard and proprietary automation protocols used to implement Industrial Control Systems, including the most common versions of Modbus and Profibus.
   
4. In programmable logic controllers and on factory floors. Since it is differential, it resists electromagnetic interference from motors and welding equipment.
   
5. In theatre and performance venues to control sound systems and lighting. The EIA-485 link is typically implemented over standard XLR cables more commonly used for microphones, and so can be run between stage and control desk without laying special cables. Theatrical and disco lighting is controlled with the DMX protocol.
   
6. EIA-485 is also used in building automation as the simple bus wiring and long cable length is ideal for joining remote devices.
   
7. It may be used to control video surveillance systems or to interconnect security control panels and devices such as access control card readers. 

PLC Input & Output Module

PLC Programming

Input Module

The input module has two functions:

1. Reception of an external signal
2. Status display of that input point

It receives the peripheral sensing unit's signal and provides signal conditioning, termination, isolation and/or indication for that signal's state. The input to an input module is in either a discrete or analog form.

Output Module

The output module serves following functions:

1. Transmits discrete or analog signals to activate various devices like hydraulic actuators, solenoids, motor starters
2. Displays the status (through the use of LEDs) of the connected output points
3. Signal conditioning
4. Termination
5. Isolation

The output module is treated in the same way as the input module by the processor.

PLC Main Features

PLC Various Definitions

• The National Electrical Manufacturers Association (NEMA) defines a PLC as a "digitally operating electronic apparatus which uses a programmable memory for the internal storage of instructions by implementing specific functions, such as logic, sequencing, timing, counting, and arithmetic to control through digital or analog I/O modules various types of machines or processes."
• One PLC manufacturer defines it as a "solid-state industrial control device which receives signals from user supplied controlled devices, such as sensors and switches, implements them in a precise pattern determined by ladder-diagram-based application progress stored in user memory, and provides outputs for control of processes or user-supplied devices, such as relays or motor starters."
• Basically, it's a solid-state, programmable electrical/electronic interface that can manipulate, execute, and/or monitor, at a very fast rate, the state of a process or communication system. It operates on the basis of programmable data contained in an integral microprocessor-based system. 

EIA Problems

EIA232 interfacing may include at least one of the following problems:

1. Absence or misconnection of flow control i.e. handshaking signals, resulting in buffer overflow or communications lock-up.
2. Incorrect communications function (DTE versus DCE) for the cable in use, resulting in the reversal of the Transmit and Receive data lines as well as one or more handshaking lines.
3. Incorrect connector gender or pin configuration, preventing cable connectors from mating properly.

Fortunately, EIA232 driver circuitry is extremely tolerant of misconnections, and will usually survive a drive signal being connected to ground, or two drive signals connected to each other. In any case, if the serial interface between two devices is not operating correctly, disconnect the cable joining this equipment until the problem is isolated.

EIA-232 Scope of the standard

The Electronics Industries Association (EIA) standard RS-232-C defines following elements:

1. Electrical signal characteristics such as voltage levels, signaling rate, timing and slew-rate of signals, voltage withstand level; short-circuit behavior, and maximum load capacitance.
   
2. Interface mechanical characteristics, pluggable connectors and pin identification.
   
3. Functions of each circuit in the interface connector.
   
4. Standard subsets of interface circuits for selected telecom applications.
   

However below mentioned elements are not defined by EIA-232 standard:

1. Character encoding like ASCII, Baudot code or EBCDIC
   
2. Framing of characters in the data stream, for example, bits per character, start/stop bits, parity
   
3. protocols for error detection or algorithms for data compression
   
4. Bit rates for transmission, although the standard says it is intended for bit rates lower than 20,000 bits per second. Many modern devices support speeds of 115,200 bit/s and above
   
5. Power supply to external devices. 

Ethernet/IP

EtherNet/IP i.e. Ethernet Industrial Protocol is an open communications protocol which was developed by Rockwell Automation and managed by ODVA. It is designed for use in process control and other industrial automation applications. This industrial application layer protocol operates over the Ethernet medium and employed for communication between industrial control systems and their components, such as a programmable automation controller, programmable logic controller or an I/O system. It is based on the Common Industrial Protocol (CIP) standard used in DeviceNet, CompoNet and ControlNet. EtherNet/IP is now an open technology which classifies Ethernet nodes as predefined device types with specific behaviors. This allows:

• Transfer of basic I/O data via UDP-based implicit messaging
• Uploading and downloading of parameters, setpoints, programs and recipes via TCP (i.e., explicit messaging.)
• Polled, cyclic and change-of-state monitoring via UDP, such as RPI and COS in Allen Bradley's ControlLogix control systems.
• One-to-one (unicast), one-to-many (multicast), and one-to-all (broadcast) communication via TCP. 

FactoryTalk Batch Capabilities

FactoryTalk Batch can be employed to

1. Create and manage recipes and execute them automatically
2. Cut down the hours needed for validating and commissioning
3. Configure physical and procedural models
4. Integrate with an extensive variety of complementary software applications
5. Collect detailed electronic batch data about your process to generate detailed reports
6. Integrate and exchange batch and recipe information with corporate information systems
7. Simulate our entire batch process 

FactoryTalk ViewPoint

Following are the main benefits of FactoryTalk ViewPoint:

1. It reduces total cost of ownership. Furthermore, no software needs to be installed and maintained on client device.
2. It extends visualization and real-time decision capabilities to browser-based remote users, together with plant managers, supervisors and mobile workers.
3. It permits System Integrators and OEMs to monitor customer installations from any location.
4. It can easily connect to customer sites, carry out diagnostics, or give remote support without having to actually present at the end-user’s site.
5. It grants immediate and easy access to critical information from the office, home or on the road via the simplicity of a web browser.
6. It supports multiple browsers and client devices for better flexibility.
7. It allows FactoryTalk View projects to be easily web-enabled without requiring application changes. 

RSLogix Emulate Benefits

Major benefits of RSLogix Emulate 5000 include:

• It has the potential to test application code and HMI screens at our desk without using real hardware.
• It reduces equipment failures and related costs resulting from application programming errors.
• It lessens our development and integration time.
• Via RSLogix Emulate 5000, one can get a head start on next project since it eliminates the need to wait for hardware or machine availability for initiating development. 

FactoryTalk VantagePoint Benefits

FactoryTalk Vantage Point grants access to an assortment of data sources, aggregates and analyzes the information into web-based reports leading to greater manufacturing effectiveness and IT agility. FactoryTalk Vantage Point can be of great help in manufacturing operations since in an incredibly short time after installation, it:

1. Overcomes economic challenges by trimming down costs and optimizing production capabilities.
2. Improves sustainability results by preserving energy, diminishing scrap and waste and reinforcing best practices and regulatory compliance.
3. Enhances global competitiveness by combining manufacturing information across all assets and resources, by reducing demand forecast errors and assuring customer commitments and contentment.
4. Augments production agility by curtailing product development and launch cycles, observing production variants, enhancing overall product quality, rising above asset constraints and most significantly, capitalizing on resource utilization. 

FactoryTalk Transaction Manager Advanced Features

FactoryTalk Transaction Manager Version 9.0 is the latest available version which consists of following enhanced features:

• Support for FactoryTalk Audit and FactoryTalk Diagnostics which enable us to log audit and diagnostic/status messages to the FactoryTalk Audit and FactoryTalk Diagnostics subsystem.
• Two new timestamp functions named OPCTimestampof() and MOPCTimestampof() are now supported by the Expression Editor in FactoryTalk Transaction Manager.
• The Expression Editor in the current version also supports both Coordinated Universal Time (UTC) and system local formats. The UTC format can be applied to the TransTimestamp(), TimeStampOf(), and OPCTimeStampOf() functions.
• It is now compatible with Windows 2003 Server R2 operating system.
• XML Import/Export Utility is now incorporated within FactoryTalk Transaction Manager which can be used manually to export and import a configuration or programmatically build and import a configuration.
• The enhanced version of FactoryTalk Transaction Manager supports FactoryTalk Activation as well which is a secure, software-based system for activating Rockwell Software products and managing software activation files. Audit messages are generated for proper administration and monitoring of activation usage. 

FactoryTalk Transaction Manager Benefits

FactoryTalk Transaction Manager

FactoryTalk Transaction Manager is a valuable tool designed to assist us better manage our manufacturing processes by integrating the critical data in our shop floor control systems with enterprise IT and other manufacturing applications. It endows us with the ideal platform on which to integrate and build the solutions needed to run our enterprise.

Industrial transaction

To comprehend the power of FactoryTalk Transaction Manager, we must figure out an industrial transaction first. In the enterprise world, transactions are used every day to tightly link multiple systems so that they act as one. An industrial transaction is just like a normal transaction, except that, instead of linking multiple database systems, it links control systems to database systems. A true, end-to-end link is established that provides the level of reliability required to support enterprise-wide integration.

FactoryTalk Transaction Manager Benefits

FactoryTalk Integrator

The FactoryTalk Integrator is an essential component of the FactoryTalk Integrated Production and Performance software suite. It broadens the reach of the Rockwell Automation Integrated Architecture by letting our plant's systems to transmit data and exchange transactions virtually with any other system. It is designed to help us in getting required data with ease and in particular, when and where we want it.

Main Features

FactoryTalk Integrator consists of following vital features:

• It offers a reliable platform for connecting Rockwell Automation MES products to ERP packages
• It furnishes us one workflow engine for synchronizing manufacturing with our business system
• It can effortlessly connect one system to another.
• It Provides connectivity to SAP using their native interfaces
• It Supports B2MML standards 

Factory Talk Gateways

FactoryTalk Historian Latest features

Most up to date features included in FactoryTalk Historian are listed below:

1. New install and configuration tool to auto discover and auto configure tags
   
2. Advanced calculation engine in the server for simple and advanced analytics
   
3. FactoryTalk View integration to trend data from FactoryTalk Historian openly
   
4. Rich set of advanced clients including SQC and FactoryTalk Batch capabilities
   
5. Time-series optimized data store
   
6. Advanced filtering through exception and compression algorithms
   
7. Event framing of data to display event metadata with the time-series data
   
8. Advanced development tools ranging from VBA, ActiveX support to advanced Visual Studio .NET support
   
9. Redundancy and high availability support
   
10. Support for an extensive number of third-party data sources

FactoryTalk Historian Benefits

FactoryTalk Gateway Advanced Features

1. FactoryTalk Gateway has enhanced diagnostic capabilities which comprise user interface improvements that contain the information required for the current status and advanced troubleshooting.
2. By improving the messages from FactoryTalk Diagnostics and providing an integrated viewing tool for counters, messages and an integrated help system, the diagnostics counter monitor and FactoryTalk Gateway greatly expands our awareness of where the current state of the server can be reviewed.
3. Via FactoryTalk Gateway we can lock down what OPC clients are permitted to do, whereas FactoryTalk Security prevents unwarranted scanning and unwarranted writing to control system tags or datapoints. This is especially helpful because OPC clients can be difficult to control since it is easy to put tags on scan in a controller.
4. FactoryTalk Gateway also enables us to share the FactoryTalk Services Platform with third-party applications, and future advancements in FactoryTalk Live Data like adding the TCP/IP protocol, and improvements in ease-of-use for the services platform, will benefit the FactoryTalk Gateway.
5. FactoryTalk Gateway has added support for additional tags, including a 70,000 tag version for large applications or small applications which need to grow. 

Other FactoryTalk Gateway Benefits

DeviceNet

DeviceNet is a communication protocol employed in the automation industry for interconnecting control devices for data exchange. It is mainly used as a communication network between industrial I/O devices and controllers like limit switches, photoelectric sensors, valve manifolds, motor starters, process sensors, bar code readers, variable frequency drives, panel displays and operator interfaces. Controller Area Network is its backbone technology and an application layer covering a range of device profiles is defined by DeviceNet. Typical applications include

• Information exchange
• Safety devices
• Large I/O control networks

Technical Features

DeviceNet includes following main features:

• It defines the Media, Physical, Data-Link, and Application layers of the ISO/OSI 7-layer model.
• On the lower layers i.e. OSI layer 1 to 4, DeviceNet fundamentally uses the CAN specifications with some constraints and extensions while on the upper layers i.e. OSI layer 5 to 7 DeviceNet uses the Common Industrial Protocol (CIP) specified by the ODVA.
• It uses the CAN data frame for information exchange.
• It also adds in trunk line topology with separate buses for signal and power. Usual configuration is two twisted pairs and a single shield.
• Defined Baud rates are 125 kbit/s, 250 kbit/s and 500 kbit/s.
• Trunk length is inversely proportional to the speed, i.e. 500, 250 and 100 meters respectively.
• Use of the quick-fix connector was allowed by adding on a new flat cable to the specification.
• It can support up to 64 nodes on a single logical network. Node addresses range from 0 - 63
• It supports master/slave as well as peer-to-peer communication, though majority of the devices work in the master/slave configuration.
• It allows several masters on a single logical network.
• Network cable can supply device power along same cable as communication cable.
• Networked devices can be both controlled and configured at the same time.
• It has the potential to withstand noisy environments. 

DeviceNet Conformance Test

SOAP Main Features

SOAP Main Features 

1. It is a lightweight protocol for exchange of information in a decentralized, distributed environment.
2. It is the successor of XML-RPC; however it borrows its transport and interaction neutrality and the envelope/header/body from somewhere else.
3. It can form the foundation layer of a web services protocol stack, providing a basic messaging framework upon which web services can be built.
4. It makes use of an Internet application layer protocol as a transport protocol.
5. It can potentially be used in conjunction with a variety of other protocols.

SOAP Message

It is an ordinary XML document which is generally sent to a web service enabled web site along with the parameters required for a search. The site would then send back an XML-formatted document with the resulting data. Since the data is returned in a standardized machine-parseable format, it can then be integrated directly into a third-party site. It basically consists of following four elements:

1. An Envelope element: It is the root element of a SOAP message which identifies the XML document as a SOAP message
2. A Header element: It contains application-specific information such as authentication, payment, etc about the SOAP message. The Header element is optional and if it is present, it must be the first child element of the Envelope element.
3. A Body element: It is the required message element which indicates call and response information. It contains the actual SOAP message intended for the eventual endpoint of the message. Immediate child elements of the SOAP Body element may be namespace-qualified.
4. A Fault element: It is an optional element which consists of errors and status information. It can only appear once in a SOAP message. If a Fault element is present, it must appear as a child element of the Body element. 

Types of Thermostats

Electromechanical or Manual thermostats: These are old-fashioned mercury units which consist of internal coils to expand or contract in response to temperature change. These types of thermostats are getting obsolete because of following two reasons:

1. Digital thermostats are able to more accurately register and respond to temperature changes
2. Purchase of products containing mercury has been restricted or banned in many states

In spite of above mentioned reasons manual thermostats remain popular owing to their low cost, the familiarity of their controls' design and ease of their use.

Manual digital thermostats: They make use of an electronic temperature sensor to register changes in the room temperature. These changes are then compared with the settings selected by the user. If there is a difference between the room temperature and the set temperature, a command is sent to the heating or cooling system necessitating action. For manual digital thermostats we need to physically adjust the setting of our preferences whenever we would like to adjust the room temperature. New digital thermostats have no moving parts to measure temperature and instead rely on thermistors or other semiconductor devices like a resistance thermometer or resistance temperature detector. They use either a relay or a triac to act as switch to control the HVAC unit. Units with relays will operate millivolt systems, but often make an audible "click" noise when switching on or off.

Programmable digital thermostats: These are up gradation of the digital manual thermostats and also referred to as setback thermostats or clock thermostats. They are more convenient to use and can help save energy costs. Once we program the thermostat to fit our lifestyle and schedule, the thermostat works automatically year-round. We simply need to program the temperatures into the memory of the unit, along with the times of day that we would like the changes to occur. Based on the model, a thermostat can be programmed in following three ways:

1. 5 - 2 programming: Maintains a set schedule for five days (weekdays), and then switches to an alternate schedule for the other two days (weekends).
2. 5 - 1 - 1 programming: Maintains a five day schedule (weekdays), then switches to first individual day (Saturday), then second individual day (Sunday).
3. 7 day programming: Allows the maximum flexibility for those with frequently-changing schedules by allowing us to program each day individually.

Other Advanced Thermostats: Various highly developed models have touch screens and the aptitude to work with home automation or building automation systems. More expensive models have a built-in PID controller, so that the thermostat knows in advance how the system will react to its commands.

Thermostat Applications & Location

Thermostats make our life more comfortable. They are used widely in HVACR which means heating, ventilation, air conditioning and refrigeration. Major applications of thermostats include:

1. Temperature control of a room to the comfort level of the occupants
2. Temperature control of a refrigerator to ensure that food is kept fresh
3. Temperature control of the operating theatre and a host of other applications

Location of Thermostat

Following point should be kept in mind while deciding the location of thermostat:

1. It should be located far-off from the room's cooling or heating vents or device. However, it is exposed to general airflow from the rooms to be regulated.
2. An open hallway may possibly be most appropriate for a single zone system, where living rooms and bedrooms are operated as a single zone.
3. If the hallway is closed by doors from the regulated spaces then these should be left open when the system is in use.
4. If the thermostat is too close to the source controlled then the system will tend to "short cycle", and numerous starts and stops can be irritating and in some cases shorten equipment life. A multiple zoned system can save considerable energy by regulating individual spaces, allowing unused rooms to vary in temperature by turning off the heating and cooling. 

FieldServer's Main Features

A Fieldserver is also known as a communications bridge, protocol converter, or communications gateway. It is basically a protocol translation device. It is user configured to enable devices which employ different communications protocols to communicate with one another. FieldServers are capable to support multiple protocols in a single bridge. Fieldserver’s are physical devices which work as a gateway enabling different devices employing different protocols to interface with each other. Besides solving communication and protocol conversion problems a Fieldserver improves response times in distributed data acquisition and control systems as well.

Main Features

• An extensive driver library is available from FieldServer Technologies which gives a broad range of interoperability solutions. Its library of protocols numbers more than 110.
• The FieldServer acts like an Ethernet gateway and enables new and legacy PLCs, RTUs and SCADA devices to link to Ethernet for plant-wide communications.
• Based on the model, the FieldServer is equipped with combinations of Serial, Ethernet and LONWORKS ports as well as various fieldbus ports.
• The internal poll-block caching capability assures that data from Server devices is straight away available to the client devices when required.
• Data can be cached from slower devices or remote units for immediate access by the client device.
• The Hot Standby option for the FieldServer is available as and when dual redundancy is required. 

BACnet MSTP

BACnet MSTP is a token passing protocol. Here the MS stands for Master - Slave and the TP stands for Token Passing. This flavor of BACnet is mainly used for connecting field devices to controllers / routers / control applications. BACnet MSTP uses RS485/EIA485 as its physical layer which allows up to 128 devices to be installed on a single network with a max physical length of 4000ft and speeds up to 115k baud. Using repeaters allows the length to be increased. General baud rates are 19200, 38400 and 76800. All devices have got to operate at the same baud rate and upon autosensing the baud rate, more and more devices configure themselves correctly.

MSTP master and slave

Only nodes with the token are permitted to initiate service requests like requests for data. A device that receives a request, a request that requires a response, might respond without having the token. Based on this behavior it is simple to understand the difference between a MSTP master and slave. A slave is a device that can only send responses. A master is an initiator of a service request.

XML Key Benefits

Separates Data from HTML: To display dynamic data in HTML document, one needs to perform lot of work to edit the HTML each time the data changes while with XML, data can be stored in separate XML files. By a few lines of JavaScript, we can read an external XML file and update the data content of our HTML.


Simplifies Data Sharing: In the real world, computer systems and databases store data in incompatible formats whereas XML data is stored in plain text format. This provides a software- and hardware-independent way of storing data and makes it much easier to create data which different applications can share.


Simplifies Data Transport: By means of XML, data can be conveniently exchanged between incompatible systems. One of the most time-consuming challenges for developers is to exchange data between incompatible systems over the Internet. Exchanging data as XML reduces this intricacy to a great extent, since the data can be read by different incompatible applications.


Simplifies Platform Changes: Upgrading to new platforms (either hardware or software), is always very time consuming since large amount of data needs to be converted and incompatible data is frequently lost. However, XML data is stored in text format which makes it easier to expand or upgrade to new operating systems, new applications, or new browsers, without losing any data.


Makes our Data More Available: Since XML is independent of hardware, software and application, it can make our data more available and useful. Diverse applications can access our data, not only in HTML pages, but also from XML data sources. Via XML, our data can be available to all kinds of reading machines like Handheld computers, voice machines, news feeds, etc, and make it more available for blind people, or people with other disabilities.


Used to Create New Internet Languages: Many new Internet languages are created with XML. Some of the examples are given below:

• XHTML the latest version of HTML
  
• WSDL for describing available web services
  
• WAP and WML as markup languages for handheld devices
  
• RSS languages for news feeds
  
• RDF and OWL for describing resources and ontology
  
• SMIL for describing multimedia for the web 

HTTP Request methods

HTTP defines following eight methods for indicating the preferred action to be performed on the identified resource

1. HEAD: This method asks for the response identical to the one that would correspond to a GET request, but without the response body. This method is useful for retrieving meta-information written in response headers, without transporting the entire content.
   
2. GET: This method is used for requesting a representation of the specified resource. GET should not be used for operations that cause side-effects, such as using it for taking actions in web applications.
   
3. POST: It submits data to be processed to the identified resource. The data is included in the body of the request. This may result in the creation of a new resource or the updates of existing resources or both.
   
4. PUT: Used for uploading a representation of the specified resource.
   
5. DELETE: It is used for deleting the specified resource.
   
6. TRACE: Use of this method echoes back the received request, so that a client can see what intermediate servers are adding or changing in the request.
   
7. OPTIONS: This request method returns the HTTP methods supported by the server for specified URL. This can be used to check the functionality of a web server by requesting '*' instead of a specific resource.
   
8. CONNECT: It converts the request connection to a transparent TCP/IP tunnel, generally to facilitate SSL-encrypted communication (HTTPS) through an unencrypted HTTP proxy.
   

HTTP servers are required to implement at least the GET and HEAD methods and, whenever possible, also the OPTIONS method.

Convert HTTP to other communication protocols

Modbus Register types

Most commonly used Modbus register types includes:

1. Coil (Discrete Output)
2. Discrete Input
3. Input Register
4. Holding Register

The address range for Modbus was originally defined from 0 to 9999 but now the currently specified range has been updated from 0 to 65,535. This address range is valid for each type of Modbus register. The function code specified in the Modbus query message packet determines what register type is being referenced. Reference range for all the four register types is mentioned below:

• 0x Coil 00001-09999
• 1x Discrete Input 10001-19999
• 3x Input Register 30001-39999
• 4x Holding Register 40001-49999

Sometimes it becomes necessary to access more than 10,000 of a register type. Additional register types and reference ranges include the following:

• 0x Coil 000001-065535
• 1x Discrete Input 100001-165535
• 3x Input Register 300001-365535
• 4x Holding Register 400001-465535

It is mandatory to use six digit register references while using the extended register referencing to easily differentiate between holding register 40001 and coil 40001. "If coil 40001 is the target, it must appear as 040001". ^[1]

Limitations

In spite of its unfussiness and simplicity, Modbus protocol embraces few restrictions as well. The most considerable limitation is its incapability to sustain and uncover description of large binary objects. Moreover Modbus being a Master/slave protocol provides no means for a field device to “Report by exception”. Also Modbus addressing restrictions up to 247 devices per data link confines the range of field devices requiring connection to a master station.

RSNetWorx

RSNetWorx products provide design and configuration management services for following installations:

1. ControlNet International's ControlNet
2. Open DeviceNet Vendor Association's DeviceNet networks
3. Ethernet I/P

With the help of RSNetWorx, maximum productivity can be attained with our ControlNet and DeviceNet installations. This simple software interface makes it possible to define and configure the devices on our network rapidly without any trouble. Devices can be defined either offline using drag and drop operations or online by using RSLinx to browse a ControlNet or DeviceNet network.

RSLogix Architect

RSLogix Architect is very simple software which can powerfully manage all RSLogix5000 based controller configuration files, network configurations, and produced and consumed tag relationships. It offers tools for:

• Controller configuration management
• Viewing the system as a whole versus a collection of configuration files
• Communications and network management
• Produced and consumed tag management

Via RSLogix Architect, we can create pages which are a living view of our network and controller. These pages are used in our automation system since control hardware layout containing the chassis, controllers, and communication modules is drawn on these pages. We can also draw networks which enable us to connect the controllers together. After the controllers get connected together through networks, produced and consumed tag relationships can be easily configured from one location. RSLogix Architect software is an ideal complement to Integrated Architecture.

FactoryTalk ProductionCentre - Benefits II

Returned Merchandise Authorization (RMA) and Repair
Use of FactoryTalk ProductionCentre assists in

• Enhanced global repair efficiencies by spending time and resources using data, leaving the task of data collection to FactoryTalk ProductionCentre
  
• Generating quick response to customer inquiries by providing customers with real-time order status via the web
  
• Rapid diagnosis of defects by relying on a view of past repairs, manufacturing history and most common repairs
• Product quality improvement by enforcing repair processes and incorporating engineering or field change orders into returned merchandise

Supplier Manager

FactoryTalk ProductionCentre works as an excellent supplier manager as it

• Provides full traceability of supplier components, reducing time required for root-cause analysis and recall management
  
• Includes supplier part management and cross-referencing capabilities
  
• Produces metrics on supplier quality such as inspection results and supplier quality trends
  
• Implements supplier sampling plans including skip lot, ANSI Z1.4, ANSI Z1.9, Dodge Romig, Zero acceptance, and first article inspections
  
• Integrates with CAPA to provide Supplier Corrective Action Requests (SCAR)
  

Analytics

This exclusive software is capable enough to

• Convert operational data into information for fact-based decision-making
• Use a single data model to span supplier, manufacturing and repair for unsurpassed insights that disparate systems can easily overlook
• Provide more than 50 web-based standard reports
• Real-time response and alerting with live transactional data reporting 

Other Benefits

FactoryTalk eProcedure Benefits

Procedure automation benefits with no expense of equipment automation are generally offered by FactoryTalk eProcedure. Few of its significant benefits include:

• It supports 21 CFR Part 11 and other regulatory requirements
• Streamlines data collection
• Provides the same consistency as automated controls for manual operations
• Utilizes an interactive, web-based interface to sequence and document manufacturing operations
• Allows choice of media for delivering operating instructions through HTML procedure delivery 

Rockwell Automation Software/RSLogix Micro - System Requirements

Following are the requirements that must be fulfilled before using RSLogix Micro Programming software:

1. IBM-compatible PC with Pentium® processor
2. Microsoft Windows XP and later
3. 32 MB of RAM (64 MB recommended)
4. 50 MB of free hard disk space (or more based on application requirements)
5. 16-color VGA Graphics Adapter, 640 x 480 or greater resolution (256-color 800 x 600 optimal)
6. Products require the use of RSLinx Classic Lite. RSLinx Classic Lite is included with RSLogix 500 

XIF Files

Files which define the network visible interface for one or more LONWORKS devices are known as LONMARK device interface i.e. XIF files.

Device Interface

It is basically an interface to a device which is exposed over a LONWORKS network. It only exposes the inputs to the algorithms and the outputs from the algorithms and does not expose the internal algorithms of a device. A device interface contains following information:

1. Device’s self documentation information
2. Number of address table entries
3. Number of message tags
4. Number, types, and directions of network variables.

The device interface can be inquired over the network to a great extent with the help of a network tool. The device manufacturer establishes the completeness of a queried interface. For instance, a device manufacturer may opt to embed network variable names in a device to make certain that the queried network interface includes these names.

Benefits

Following are the benefits to using device interface files:

1. A device interface file may contain information that is not available in a device such as network variable names.
2. Besides, a device interface file can be employed during network engineering when the device is not accessible from the network engineering tool. 

Subnetting

Subnet 

It is used to break the network into smaller more efficient subnets to avoid excessive rates of Ethernet packet collision in a large network. Such subnets can be arranged hierarchically, with the organization's network address space partitioned into a tree-like structure. Routers are employed to manage traffic and constitute borders between subnets.

A typical subnet is a physical network served by one router. For example, an Ethernet network consisting of one or several Ethernet segments or local area networks, interconnected by network switches and network bridges or a Virtual Local Area Network. It is possible to divide a physical network into several subnets by configuring different host computers to use different routers. While improving network performance, subnetting increases routing complexity, as each locally connected subnet is typically represented by one row in the routing tables in each connected router.

Subnet mask

It enables us to identify that part of an IP address which is reserved for the network, and the part which is available for host use.

Routers - Introduction

Router is a networking device whose software and hardware are typically customized to the tasks of routing and forwarding information. For instance, on the Internet, information is directed to various paths by routers. Routers connect two or more logical subnets, which do not essentially map one-to-one to the physical interfaces of the router. It operates in two different planes:

1. Control plane: It is a plane in which the router learns the outgoing interface that is most appropriate for forwarding specific packets to specific destinations.
   
2. Forwarding plane: A plane which is responsible for the actual process of sending a packet received on a logical interface to an outbound logical interface.

Brief Description

In packet-switched networks like Internet, a router is a device or, in some cases, software in a computer which decides the next packet forwarding point in a network. The router is connected to at least two networks and decides which way to send each information packet based on its current understanding of the state of the networks it is connected to. A router is located at any gateway i.e. a point where one network meets another including each point-of-presence on the Internet. A router is often included as part of a network switch.

A router creates and maintains a table of the accessible routes and their conditions and makes use of this information along with distance and cost algorithms to establish the best route for a given packet. Normally, a packet travels through a number of network points with routers before arriving at its final destination. Routing is a function associated with the Network layer i.e. layer 3 in the Open Systems Interconnection (OSI) model (the standard model of network programming). A layer-3 switch is a switch that can perform routing functions.

Router Components

Rockwell Automation Software/FactoryTalk Portal

The FactoryTalk Portal is a part of the FactoryTalk Integrated Production and Performance Suite. It enables manufacturers to merge their Web-based interfaces into single configurable and convenient launch point. In our manufacturing processes FactoryTalk Portal furnishes:

• Improved productivity through personalized and collaborative access to information, applications, processes, and people.

• Information where it needs to go and to the right people.

• Reduced Total Cost of Ownership (TCO) by providing a platform for manufacturing applications.

Services offered

FactoryTalk Portal server software presents core portal services like

1. Role-based access to applications and content
2. Search
3. Personalization
4. Security
5. Portlet development capabilities (the visible, active components in a portal page). 

Winpcap

Pcap i.e. packet capture consists of an application programming interface (API) for capturing network traffic. Unix-like systems implement pcap in the libpcap library whereas Windows uses a port of libpcap known as WinPcap. WinPcap is the packet capture and filtering engine of many open source and commercial network tools, including protocol analyzers, network monitors, network intrusion detection systems, sniffers, traffic generators and network testers. Popularly known tools include Wireshark, Nmap, Snort, ntop etc. WinPcap contains a driver that extends the operating system to provide low-level network access, and a library that is used to easily access the low-level network layers.

Sniffer

It is also known as a packet analyzer, network analyzer or protocol analyzer. It is a computer software or computer hardware which intercepts and logs traffic passing over a digital network or part of a network. As data streams flow across the network, the sniffer captures each packet and ultimately decodes and analyzes its content according to the appropriate RFC or other specifications. A packet sniffer is used to:

• Analyze network problems

• Detect network intrusion attempts

• Gain information for effecting a network intrusion

• Monitor network usage

• Gather and report network statistics

• Filter suspect content from network traffic

• Spy on other network users and collect sensitive information such as passwords

• Reverse engineer proprietary protocols used over the network

• Debug client/server communications

• Debug network protocol implementations 

REST Interaction, Protocol Servlets & Example

A REST interaction generally includes following elements:

• Operation— It belongs to a restricted, well-known set of operations—for example, in the HTTP protocol, the main operations are GET, POST, PUT, and DELETE. The operations are all known in advance hence no need arises to define interfaces for a RESTful protocol. In this regard, REST architecture is advantageous as compared to RPC architectures.
  
  
• URI— It identifies the resource that the operation acts on. For example, a HTTP GET operation acts on the URI by fetching data from the resource identified by the URI.
  
  
• Data (Optional)— It is required for operations that send data to the remote resource.
  

REST Protocol Servlets

The REST protocol is implemented by the following servlets running in a Web container:

• message servlet— It supports the sending and consuming of messages.
• queueBrowse servlet—It enables us to monitor the contents and view the current status of a particular queue. It is an effective and simple management tool.
  

RESTful Example

The World Wide Web is a major example of RESTful design and conforms to REST principles to a large extent. The Web consists of the Hypertext Transfer Protocol (HTTP), content types including the Hypertext Markup Language (HTML), and other Internet technologies such as the Domain Name System (DNS).

• HTML can include JavaScript and applets to support code on demand, and has implicit support for hyperlinks.
• HTTP has a uniform interface for accessing resources, which consists of URIs, methods, status codes, headers, and content distinguished by MIME type.

HVAC - Ventilation

Building ventilation

The process of bringing outside air into a building, circulating it, and later purging it to the environment is known as Building ventilation. The purpose behind ventilation is to provide adequate indoor air quality by diluting and removing contaminants from the indoor air. This can be achieved either by natural or mechanical means, or by a combination of both.

Natural ventilation

Natural ventilation is done by using air pressure differences existing between the inside of a building relative to the outside of it, across the building envelope. Natural forces such as wind and temperature create these air pressure differences. In naturally ventilated buildings air moves through windows, doors, vents and other openings built-in into the building design and via infiltration/exfiltration.

Mechanical ventilation

Mechanical ventilation is done by utilizing mechanical air handling systems which are commonly referred to as heating, ventilation, and air conditioning i.e. HVAC systems. Mechanical ventilation is more controllable and responsive as compared to natural ventilation in providing adequate indoor air quality hence employed in mainly commercial buildings. An HVAC system provides adequate indoor air quality by:

• Conditioning the air in the occupied space of a building

• Diluting and removing contaminants from indoor air through ventilation

• Providing proper building pressurization. 

Simple Network Management Protocol( SNMP) Part 2

 Basic Commands

Four basic SNMP commands used for monitoring and controlling managed devices include:

1. Read command: It is used by an NMS to monitor managed devices. The NMS examines different variables that are maintained by managed devices.
2. Write command: It is used by an NMS to control managed devices. The NMS changes the values of variables stored within managed devices.
3. Trap command: It is used by managed devices to asynchronously report events to the NMS. When certain types of events occur, a managed device sends a trap to the NMS.
4. Traversal operations: These operations are executed by the NMS for determining variables supported by a managed device and to sequentially gather information in variable tables, such as a routing table.

SNMP Management Information Base (MIB)

MIB is a collection of hierarchically organized information which is accessed using a network-management protocol such as SNMP. MIBs include managed objects and are identified by object identifiers.

• A managed object also known as a MIB object, an object, or a MIB consists of one or more object instances, which are essentially variables. Two types of managed objects are:

    Scalar objects which define a single object instance and Tabular objects which define multiple related object instances grouped in MIB tables.

• An object identifier also known as object ID uniquely identifies a managed object in the MIB hierarchy. The MIB hierarchy can be shown as a tree with a nameless root, the levels of which are assigned by different organizations. 

Introduction: Simple Network Management Protocol ( SNMP)

LonWorks Physical Layers 3 & 4

Layer 3: Network Layer

This layer is for Destination Addressing and specifies the destination of a message on the network. This corresponds to the area and long distance codes on the telephone network. Services provided by this layer include:

• Node address information
• Routing of messages to segment and control network bandwidth usage
• Services such as determining which nodes on the network receive various messages.
• The ability to provide routers to segment the traffic and communicate between different physical media.

Layer 4: Transport Layer

This layer is for End to End Reliability and defines the type of services needed for the node messages depending on the level of reliability required by the application. The services provided are:

• Broadcast addressing
• Unicast addressing
• Multicast addressing
• Repeated service
• Acknowledged service
• Unacknowledged service
• Duplicate packet detection
• Authentication 

Layer 1 & 2

LonWorks - SNVT elec kwh

SNVT Name: SNVT_elec_kwh
SNVT Index: 13

• The number of Data Array elements required i.e the data length for SNVT_elec_kwh when specifying a Data Array name under a Map Descriptor is1.
  
• The value range allowed for this SNVT type is 0 .. 65,535 and the values outside this range will not be processed in a read or write on SNVT_elec_kwh's value data item.
  
• The suggested data array format for SNVT_elec_kwh is Uint16 i.e. 16-bit Unsigned Integer, Float format.
  
• Invalid value will always be "Not applicable" (N/A).
  
• SNVT_elec_kwh contains only one data item named Electrical energy which is measured in Kilowatt-hours. 

LonWorks – SNVT density f

LonWorks - SNVT btu kilo

SNVT Name: SNVT_btu_kilo
SNVT Index: 5

• Number of Data Array elements required i.e the Data length for SNVT_btu_kilo when specifying a Data Array name under a Map Descriptor is 1.
• The value range allowed for this SNVT type is 0 .. 65,535 and the values outside this range will not be processed in a read or write on SNVT_btu_kilo's value data item.
• The suggested data array format for SNVT_btu_kilo is Uint16, Float format.
• Invalid value will always be "Not applicable" (N/A).
• It contains only one data item named Thermal Energy which is measured in Kilo-British Thermal Units.

LonWorks - SNVT btu f

SNVT Name: SNVT_btu_f
SNVT Index: 67

• Number of Data Array elements required i.e the Data length for SNVT_btu_f when specifying a Data Array name under a Map Descriptor is 1.
• The value range allowed for this SNVT type is 0 .. 3.40282E38 and the values outside this range will not be processed in a read or write on SNVT_btu_f's value data item.
• The suggested data array format for SNVT_btu_f is 32 Bit Float format.
• Invalid value will always be "Not applicable" (N/A).
• It contains only one data item named Thermal Energy  which is measured in British Thermal Units. 

LonWorks - SNVT angle f

SNVT Name: SNVT_angle_f

SNVT Index: 49

    The number of Data Array elements required i.e the data length for SNVT_angle_f when specifying a Data Array name under a Map Descriptor is 1.
    The Value range allowed for this SNVT type is -3.40282E38 .. 3.40282E38 and values outside this range will not be processed in a read or write on SNVT_angle_f's value data item.
    The suggested data array format for SNVT_angle_f is 32-bit Float format.
    Invalid value will always be "Not applicable" (N/A).
    Like SNVT_angle, it contains only one data item named Phase/Rotation measured in Radians only.

Lonworks SNVT count f

LonWorks - SNVT count

SNVT Name: SNVT_count
SNVT Index: 8

• The number of Data Array elements required i.e the data length for SNVT_count when specifying a Data Array name under a Map Descriptor is1.
  
• The value range allowed for this SNVT type is 0 .. 65,535 and the values outside this range will not be processed in a read or write on SNVT_count's value data item.
  
• The suggested data array format for SNVT_count is Uint16 i.e. 16-bit Unsigned Integer, Float format.
  
• Invalid value will always be "Not applicable" (N/A).
  
• SNVT_count contains only one data item named Event Count measured in counts only.

SNVT Index: 95

M10K Format

Introduction

The Modulo-10000 (M10K) format breaks a 32-bit value into two 16-bit registers, according to the following relationship:
High-Order Register = value 10000
Low-Order Register = value modulus 10000
The 32-bit value can be retrieved by the following calculation:
value = registerhigh x 10000 + registerlow

Example

Value 12345678 is passed in unsigned 32-bit Modulus-10000 format.
Registerhigh: 1234 = 04D2 Hex
Registerlow: 5678 = 162E Hex
value = 1234 * 10000 + 5678 = 12345678

Another Example

Value -12345678 is passed in signed 32-bit Modulus-10000 format.
Registerhigh: -1234 = FB2E Hex
Registerlow: -5678 = E9D2 Hex
value = -1234 * 10000 + -5678 = -12345678

CIP Motion, Safety & Advantages

What is CIP

CIP Motion

It is an extension to EtherNet/IP which enables integration of field devices and motion drives on the same network and at the same time purges the requirement for a separate motion optimized network. This gives lower system cost, improved system performance, and greatly reduced system complexity.

CIP Safety

It provides the capability to have a blend of safety devices and standard devices on the same network or wire for seamless integration and improved flexibility. The safety protocol provides fail-safe communication between nodes such as safety I/O blocks, safety interlock switches, safety light curtains and safety PLCs in safety applications up to Safety Integrity Level (SIL) 3 according to IEC 61508 standards.

Advantages

1. Coherent integration of I/O control, device configuration and data collection.
2. Seamless flow of information across multiple networks.
3. Ability to implement multi-layer networks without the added cost and complexity of bridges and proxies.
4. Minimized investment in system engineering, installation and commissioning.
5. Freedom to choose best of breed products, with the assurance of competitive prices and low integration cost.

LonWorks Glossary

Neuron ID

It is a address that is hardware dependent and changes according to the hardware. The network management tool must have the Neuron ID for commissioning a device. The Neuron ID does not contain any information about the device address. A unique 48 bit Neuron ID associated with each LonWorks device results in approximately 300 trillion different combinations when it gets burnt into the Neuron chip during the manufacturing process. When a device is pinned, the Neuron ID is broadcasted through the network so that a logical address (Subnet/Node ID) can be assigned.

Subnet/Node ID

Subnet is a logical collection that consists of up to 127 devices within a domain and all devices in a subnet must be on the same segment. With one subnet, the LNS Network Interface is assigned a Subnet/Node ID of 1/127, whereas all other device’s Subnet/Node IDs begin with an address of 1/1 and increase sequentially to 1/2, 1/3, etc. These values are automatically assigned by the network management tool. Up to 255 subnets can be defined within a single domain. Subnets cannot cross non-permanent type routers. The address is hardware independent i.e. whenever a device gets replaced; the new device uses the same Subnet/Node ID in spite of new one. The node ID identifies a device on a subnet. It is actually a logical address assigned to a device after it has been commissioned. The subnet segment of the ID is employed to route packets. Packets will be available to other channels/subnets only according to the requirement. The other channels include: the source channel, the destination channel and all channels between the source and destination. A device’s Neuron ID and Subnet/Node ID both can be found in the Identifiers tab of the device’s properties.

LNS (LonWorks Network Services)

LNS which is basically a client-server operating system developed by Echelon Corporation provides directory, installation, management, monitoring, and control services required for open LonWorks networks. It is a platform that permits multiple LNS applications to interoperate on the same personal computer (PC) or on multiple PCs on the same network. A single LNS Server can support many interoperating client applications. The LNS Server has the capability to work as a standalone application on a PC attached to the network, or on the same PC as the Network Management tool. Besides remote clients i.e. Clients on other PCs can log into the LNS Server to access the shared LNS database. API products cannot be commissioned using LNS tool and vice versa because API networks function as a peer-to-peer network and employ a different database structure than client-server model. Network Management tools using the client-server capabilities of LNS allow multiple Network Management tools running on different PCs to simultaneously access the same LNS Server. This capability allows several users to work at the same time on a single network. An application that uses the services of the LNS Server is called LNS client and the host application that uses an NSI as its network interface is called an LNS host application. This host application utilizes the services, events, and properties provided by an NSS to perform network installation, configuration, maintenance, repair, monitoring, and control. It can also implement its own application-specific services, events, and properties and, through the LNS architecture, make these available to other LNS host applications.

Lonworks Glossary II
Lonworks Glossary III

ControlNet - Data transfers

ControlNet supports both scheduled and unscheduled transfers.

Scheduled Transfer

Time critical data is scheduled data and deterministic and repeatable transfers that are continuous and asynchronous to the ladder logic program scan are called Scheduled data transfers. It occurs at a consistent rate that is either at the same or faster than the rate specified in an I/O map-table entry.

Unscheduled Transfer

Non-time critical data is unscheduled data and non-deterministic data transfers through ladder-initiated communication or programming devices are known as unscheduled transfers.A ControlNet network allows unscheduled messaging when deterministic delivery is not required. Unscheduled operations include unscheduled non-discrete I/O data transfers through ControlNet I/O Transfer instructions (CIOs)in the PLC ladder program and peer-to-peer messaging through Message instructions (MSGs) in the PLC ladder program. Unscheduled transfers are performed during the unscheduled time in the network update interval.  Number of nodes,application program, Network Update Time(NUT), etc. help determine how much time there is for unscheduled messaging.

Network Update Time (NUT)

It is the repetitive time interval in which data can be transmitted over the ControlNet network. Data cannot transfer faster than NUT.