JetNet 5010G is a Managed Industrial Ethernet Switch equipped with 7 10/100TX ports and 3 10/100/1000 RJ-45/100-FX/Gigabit SX/LX combo ports. 2 of the gigabit ports are used to form the nonstop Rapid Super Ring; the 3rd gigabit port is used to connect the upper switch, couple ring or public server. The industrial embedded computer gigabit combo port design allows for flexibility to choose copper or fiber media, 100Base-FX or 1000Base-X, multi-mode or Single mode, for different distances and without stocking different switch models.

JetNet 5010G is designed with a rugged surface in aluminum material, solid design, and a wide operating temperature.

The industrial embedded computer software supports full Layer 2 management features, multi-form ring redundancy, network control, monitor, security and notification.

JetNet 5010G also provides built in watchdog timer, and digital input and relay output to avoid undetected damage.

Blown away by the Industrial Managed POE Switch? Korenix also provides a monitoring architecture which is applicable to many different markets, such as POS, banking, telecom, transportation, industrial automation, energy, power, military, and medical fields. Field site devices such as PLCs, sensors, meters, RFID readers…etc. can be connected to the JetBox 8210 through serial ports, USB ports, and DI/DO. The JetBox 8210 performs as an intelligent agent to monitor the status of field devices and transmit messages to back-end technicians through its dual Industrial Ethernet Switch ports or USB wireless dongle while abnormities occur. Further, the JetBox 8210 with Modbus gateway function let industrial automation developers consolidate field devices into SCADA system easily.

Watch the video related to modbus

Using an oscilloscope to display Modbus data pulses (RS-485 serial network).

Help answer the question about modbus

From my understanding i see it as a software identity number that allows various bits of hardware to locate and interact with eachother?

About Author

Korenix Technology is your one-stop supply center for industrial communications and networking products. Established by a group of professionals with more than 10 years of experience in the arenas of industrial control, data communications and industrial networking applications. Korenix is well-positioned to fulfill your needs and demands by providing a great variety of tailor-made products and services.visit our site http://www.korenixusa.com/

Compact Solution for Reliable Network Management!

Korenix is pleased to release the brand new performance-optimized JetBox 5300-w Industrial embedded computer Linux with -40 to 80? wide operating temperature for front-end industrial control deployments. The RISC-based computer with low power consumption brings flexibility and reliability to the industrial networking market through its rich interface, featuring 2 LAN ports, 2 USB ports, 2 RS232/422/485 and 2 RS232 serial ports. In addition, the compact JetBox 5300-w carries 4 DI & 4 DO channels allowing users to integrate alarms, indicators, and sensors into their complex networking system.

Main features of JetBox 5300-w are:

RISC CPU low power consumption

-40~80? operating temp, fan-less design

Linux programming

Linux customized configuration auto-run via SD card

4-port serial: TCP server mode

Digital I/O controller: 4 DI & 4 DO, DIO scheduling

SNMP control

Modbus gateway (optional)

The JetBox 5300-w supports the Korenix Auto-Run customization setting on SD card, POE Switch which allows users to configure their own Linux commands once the system is booted. By storing the customized data onto the SD card, software engineers can automatically run specific configurations or run specific applications in the JetBox 5300-w embedded computer making the industrial network management easier and more flexible.

Besides, users can benefit from the optional Modbus Gateway function for Modbus applications by enabling serial Modbus RTU devices to communicate with Modbus TCP devices.

In addition to its advanced software features, the fan-less JetBox 5300-w with redundant dual power inputs and -40 to 80? wide operating temperature range provides reliable and secure data management in harsh environmental conditions, becoming the perfect solution for open-pit mines, railcars, railways, public utilities etc

Korenix USA, based in Industry, California, services all of North, South & Central America by providing hardened, cost-effective, and Industrial Ethernet Switch for the and Rugged applications. With the award winning JetPoE Industrial Managed PoE Switch and JetBox Industrial Embedded Computer, these flagship products lead the way in industrial automation, power utility, telecommunications, and outdoor markets such as, traffic control and video surveillance. Korenix USA supplies the extra edge for Industrial Networking!

Watch the video related to modbus

This is a VERY impromptu RS-485 Modbus network formed by five process controllers acting as Modbus slaves and a personal computer acting as the Modbus master. Configuration software is used to access parameters in the networked controllers using Modbus data packets to shuttle information back and forth between the controllers and the master computer.

Help answer the question about modbus

About Author

Korenix Technology is your one-stop supply center for industrial communications and networking products. Established by a group of professionals with more than 10 years of experience in the arenas of industrial control, data communications and industrial networking applications. Korenix is well-positioned to fulfill your needs and demands by providing a great variety of tailor-made products and services.

Companies whose product objectives include reducing costs or waste, more reliable equipment management; improved physical asset control or greater situational awareness should investigate the variety of capabilities wireless sensor systems can provide. In addition to the potential savings in energy, there are likely many additional cash benefits to be found.

With 22% of the globe’s energy consumption, the US is the largest energy consumer and lowest energy producer of any developed economy in the world. The result? It is the most CO2 intensive nation in the world with a daily consumption of 6 gallons of oil per person per day or 19 tons of carbon dioxide per capita annually. This is 80% higher than Europe and 94% higher than Japan.

The greatest sources of US energy expenditure are:

• Industrial Energy 35% (chemicals, steel, processing etc)

• Road transportation is 25%

• Residential energy consumption 21%

• Commercial buildings 16%

Over the next decade, those sectors of the economy driven by consumer demand are the ones which will most rapidly increase greenhouse gases – buildings and houses.

The good news is that there are multiple opportunities to improve upon these areas. For example, the demand for energy could be reduced by 25 to 30% through a series of low cost, high return steps:

• Monitor & control of energy consumption specifically heating and cooling in homes and buildings – Smart Grid

• Replacement of incandescent bulbs with compact florescent lighting

• Equipment replacement, choosing high-efficiency water heaters and Energy StarTM appliances when it’s time for new These seemingly small steps save energy and reward investment with a rapid payback of less than 2 years, although many are immediate and some actually pay for themselves instantaneously.

In fact, according to the McKinsey Report “Reducing U.S. Greenhouse Gas Emissions: How Much What Cost” 40% of the total options for reducing greenhouse gases do not cost, rather releases money into the economy.

As the recognition not only of the costs of global warming, but also the savings to be realized with replacement and upgrading, become apparent, opportunities abound! There are numerous initiatives and programs supporting environmentally friendly products and solutions which continue to unfold at a breakneck pace. These initiatives are for products designed to be manufactured using greener processes and handled responsibly at the end of their life cycle as well as those specifically designed to aid industries and individuals in reducing their carbon footprint. Products such as Western Digital’s GreenPower hard drives and Seimens hybrid drive system for buses reduce energy consumption and CO2 emissions up to 40 percent. Both were developed under green initiatives and are taking their industries by storm.

Green Engineering, what is it?

Clean Energy Act, RoHS & WEEE

WEEE As of August 13, 2005, producers have been required to finance the collection, treatment, recycling and recovery of all Waste Electrical & Electronic Equipment

RoHS As of July 1 2006 Electrical & Electronic Equipment may no longer be sold in the European Union if it contains any of six banned substance Restriction of Hazardous Substances On March 1 2007 the first phase of Administration on the Control of Pollution Caused by Electronic Information Products came into effect.

The Climate Control Bill introduced by Representatives Edward Markey (D-Mass.) & Henry Waxman (D-Calif.) in May of 2009 introduced the most recent version of the American Clean Energy & Security Act and aims to reduce greenhouse gas emissions by 17% below 2005 levels by the year 2020. It would distribute up to 85 percent of pollution permits in a proposed cap-and-trade program.

The Carrot & Stick

Cash & Energy Savings Using Wireless Sensor Networks

Industries everywhere are finding ways to save not only on energy and it’s costs but through the use of wireless networks, in numerous other ways too.

According to Oak Ridge National Laboratories, through the use of wireless sensor networks, savings on energy for motors used in industrial processes could improve efficiency by 20%, resulting in significant cost savings. Wayne Manges said: “With electric motor-driven systems accounting for nearly one-fourth of all electricity consumption in the United States, the potential for savings is huge.”

The Department of Energy’s Industrial Technologies Program works with US industry to improve environmental performance and energy efficiency. The ITP is distributing 15 million to support R&D specifically to improve energy efficiency in industrial processes. Already a number of new wireless sensor products are being developed together with the Department of Energy.

Cost savings with wireless systems are recognized in multiple areas including materials and labor where the cost of running wire in plants ranges between $155 and $3,700 per foot. The typical payback for wired systems is 24 months and less than a quarter of that for a wireless equivalent, only six months. Add in the on-going energy savings and the return on investment decision is very clear.

In a large number of industries, companies are recasting their product lines to implement wireless technologies. “We can’t think of any segment of the industry that isn’t going to be impacted by this,” states Honeywell’s CTO Dan Shiflin.

Wireless sensor networks of all varieties are exploding into our world. There is a massive amount of research & development, from academia to start-ups, pushing to create proverbial “better-faster-cheaper” products. A growing number of products are based on an emerging specification “ZigBee”. A majority of utility companies that have settled on a standard have identified ZigBee as their preference due in main to its inherent security capabilities. Real-time data from wireless sensors networks will enable companies to achieve greater productivity and efficiency by continually improving their processes.

Named BP International’s first Director of Technology & Sensory Networks, for the oil company’s Technology Office, Ken Douglas said “You don’t ask people ‘How would you use ZigBee?’ Because they don’t know, but if you ask them: ‘How would you use information that you can now access for the first time?’ They have to think about it for a bit, but then the ideas just starting pouring out.”

In addition to the benefits of ZigBee’s security layers, the mesh network is highly reliable, flexible and can connect a variety of sensors simultaneously including protocols such as OPC, Modbus and HART.

The technologies for green engineering are not only cost effective, if done right, they are cash positive. When it comes to the design and development of products that are energy efficient and eco-friendly, as well as cost effective, wireless sensor networks make “better faster cheaper” energy saving products. Electronic designs using Zigbee products are making home sensors and energy saving devices a reality.It is less expensive when you get smarter, simpler products with better resource utilization while conserving precious resources.

Engineering…great profession…

“Engineering … it is a great profession. There is the fascination of watching a figment of the imagination emerge through the aid of science to a plan on paper. Then it moves to realization in stone or metal or energy. Then it brings jobs and homes to men. Then it elevates the standards of living and adds to the comforts of life. That is the engineer’s high privilege.”

Herbert Hoover, Civil Engineer, 1929. 31st President

Watch the video related to modbus

Screenshot do ModBus V3

Help answer the question about modbus

From my understanding i see it as a software identity number that allows various bits of hardware to locate and interact with eachother?

About Author

Jody Singleton is the president of Advantage. Incorporated 1993. Broomfield, Co
303-0410-0292
http://advantage-dev.com/Green_Energy.html

Uninterruptible power supplies (UPS) are sophisticated, microprocessor-controlled systems, capable of providing a range of alarm notifications and real-time monitoring information at local, network and remote site locations.

This is important because it offers peace of mind and negates the need for ‘warden-type’ manual inspection of power protection equipment. However, monitoring for alarm conditions is required. The beauty of today’s UPS equipment is that it can now be carried out at one location, either centrally in-house or off-site at a specialist UPS monitoring provider. Many leading power protection manufacturers, such as Riello UPS, provide this type of service. It often means an engineer can be on-site and have equipment repaired, checked and running before the client is even aware of a problem.

The decision not to outsource uninterruptible power supply monitoring must be reinforced by the provision of dedicated monitoring personnel in-house whose responsibility it is to monitor and respond to UPS alarms. Failure to act in a timely and appropriate manner will significantly reduce system resilience. Typical examples include failure to notice that a UPS is operating in bypass mode or that there is a failed battery in a battery string (note: a UPS battery string is only as strong as its weakest battery).

The advent of Html capability in the software arena has enabled modern UPS manufacturers to integrate sophisticated onsite and remote monitoring capability within their hardware. In fact, modern systems enable remote 24/7 monitoring (either by the client or at the manufacturer’s facility) of all critical UPS, generator, air-conditioning and fire suppression equipment. As well as alerting system managers to problems as they arise, integration of monitoring functions into existing infrastructures gives businesses valuable early warning of impending power and other equipment failures that actively increases profitable uptime.

Most UPS are available with software packages that monitor mains voltage, UPS load and battery charge as standard, as well as proprietary monitoring and control software, which allows remote interrogation of UPS logs and operating parameters to help diagnose alarms and faults. When instructed to do so, UPS software can remotely perform automated and controlled shutdown of valuable equipment – ensuring hardware protection while freeing personnel for other tasks during power continuity incidents.

Types of alarms include:

Audible Alarms: audible signals are generated from within the UPS or a connected remote status panel and may be coded, using varying lengths of sound, to indicate specific alarm conditions. Audible alarm signals will remain ‘on’ until the condition is rectified or the alarm is acknowledged and silenced.

Visual Alarms: light Emitting Diodes (LEDs) provide a basic form of visual alarm notification. They may be single or multi-coloured and indicate the status of the UPS by employing one of three modes: on, flashing or off.

Some UPS utilise Liquid Crystal Display (LCD) with push-button controls to provide a slightly higher level of visual alarm capability. In this case, the user can scroll through a menu of information (measurements and logs).

The most sophisticated level of visual display is a full front-panel graphic-type, which typically consists of multi-character back-lit lines that display information in alpha, numeric and symbolic formats, either as text, alarm codes, graphics or a combination thereof.

Remote communication can utilise one of several protocols to provide data-exchange between an application and its UPS: serial connection (including RS-232), Simple Network Management Protocol (SNMP), MODBUS/JBUS or Profibus.

A range of UPS monitoring packages are available from UPS suppliers – from simple installation software designed to run on laptops, PCs and PDAs to more sophisticated monitoring and control software that runs on an enterprise server (whether Microsoft Windows, UNIX, Mac, HP and many others) and provides a host of information from UPS operating conditions to WAP availability.

There are two common approaches to monitoring and control by uninterruptible power supply manufacturers: centralised and decentralised. Centralised is where a specified server is used to control the orderly shutdown of the mixed platform network. Decentralised is where each individual server or PC runs its own copy of the monitoring software and controls its own shutdown procedure. The centralised approach is the most straightforward and least expensive to install but it can introduce a single-point-of-failure into the system. Should the control server hang and fail to shutdown the rest of the routine will be disrupted leading to potential data loss and a system-wide crash. With the decentralised approach, if one server or PC fails to shut down, the problem is isolated, thus achieving a higher level of system resilience.

The human instinct upon hearing or seeing an alarm is often to ignore it but planning how to monitor uninterruptible power supplies and associated alarm signals, and conceptualising appropriate responses, is an important aspect of a power continuity plan. If you want to go into it in more detail, there is a whole chapter devoted to it in The Power Protection Guide.

Watch the video related to modbus

How to connect an oscilloscope to display Modbus data signals (RS-485 pulses) using two channels — differential signal measurement, not ground-referenced.

Help answer the question about modbus

About Author

Robin Koffler is the General Manager for Riello UPS Ltd the UK subsidiary of Riello UPS (RPS S.p.A) a leading European manufacturer of Uninterruptible Power Supplies and a co-author with Jason Yates of The Power Protection Guide(ISBN 978-0-9554428-0-3)- available from Amazon.com

Bedford Associates, founded by Richard Morley introduced the first Programmable Logic Controller in 1968.  This PLC was known as the Modular Digital Controller from which the MODICON company derived its name.  The History of the PLC as told to Howard Hendricks by Dick Morley provides an interesting insight into the early development of the PLC.

 Schnieder Quantum PLC

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Programmable Logic Controllers were developed to provide a replacement for large relay based control panels.  These systems were inflexible requiring major rewiring or replacement whenever the control sequence was to be changed.

The development of the micro processor from the mid 1970’s have allowed Programmable Logic Controllers to take on more complex tasks and larger functions as the speed of the processor increased.

Ladder Logic

PLC had to be maintainable by technicians and electrical personnel.  To support this the programming language of Ladder Logic was developed.  Ladder Logic is based on the relay and contact symbols technicians were used to through wiring diagrams of electrical control panels.

Until recently there has been no formal programming standard for PLC’s.  The introduction of the IEC 61131 Standard in 1998 provides a more formal approach to coding.  PLC Manufacturers have so far been slow on the uptake of the standard with partial implementation.  The SearchEng articleIEC 61131-3, a Standard for PLC Software by R.W. Lewis provides an introduction to the standard.

The documentation for early PLC Programs was either non existent or very poor, just providing simple addressing and basic comments, making large programs difficult to follow.  This has been greatly improved with the development of PLC Programming Packages.

SCADA and HMI

The early programmable logic controllers interfaced with the operator in much the same way as the relay control panel, via push-buttons and switches for control and lamps for indication.

The introduction of the Personal Computer (PC) in the 1980’s allowed for the development of a computer based interface to the operator, these where initially via simple Supervisory Control and Data Acquisition (SCADA) systems and more recently via Dedicated Operator Control Panels, known as Human Machine Interfaces (HMI).

The History of the PLC
as told to Howard Hendricks by Dick Morley

The following are some fables associated with the first ten years of the programmable controller business. These Fables may or may not have a basis of truth, but in general, they are the best that my Alzheimer-plagued memory can do at the moment. As has been often in other articles and reports, the startup of Modicon and the programmable controller industry as a whole is well documented. The programmable controller was detailed on New Year’s Day, 1968, and from hence till now, a slow steady growth has allowed the manufacturing and process control industries to take advantage of applications-oriented software.

The early days however, were not as straightforward nor as simple. We had some real problems in the early days of convincing people that a box of software, albeit cased in cast iron, could do the same thing as 50 feet of cabinets, associated relays and wiring. The process was indeed difficult, and deserves some of the stories that I hope the reader will be regaled with as he proceeds onward through the tortuous swamp of my mind.

One of my earliest recommendations was that the programmable controller, according to my own system architecture specification, did not need to go fast because I felt as though speed was not a criteria because it would go as fast as we needed it to. The initial machine, which was never delivered, only had 125 words of memory, and speed was not a criteria as mentioned earlier. You can imagine what happened! First, we immediately ran out of memory, and second, the machine was much too slow to perform any function anywhere near the relay response time. Relay response times exist on the order of 1/60th of a second, and the topology formed by many cabinets full of relays transformed to code is significantly more than 125 words. We expanded the memory to 1K and thence to 4K. At 4K, it stood the test of time for quite a while. Initially, marketing and memory sizes were sold in 1K, 2K, 3K, (?) and 4K. the 3K was obviously the 4K version with constrained address so that field expansion to 4K could easily be done.

The question of speed, in part, was part of the early designs. No interrupts were necessary because the external signal conditions were directly written onto memory without any supervisory requirements or “operating system of the conventional type. This allowed the processor to pay attention to solving logic rather than housekeeping the I/O. As a result, of course, the processor had to have significantly more processing power than normally associated with this size computer; and secondly, the system had to be made to run fast.

We increased the memory size, as mentioned above, but to get it to run fast, we had to break up the machine into three distinct components. Initially, the programmable controller was conceived of a processor board and a memory, and that the algorithmic and logical manipulation would be done in software. This approach was painfully slow, both on the generic “store bought computers, and other items.

We did, however, manage to substantially speed up the machine by making a third major component. This was called the logic solver. A logic solver board solved the dominant algorithms associated with solving ladder logic without the intervention and classical software approach of general-purpose processing. This meant that we ended up with three boards; memory, logic solver and processor. This single step allowed us to get the speed we needed in this application-specific computer to solve the perceptually simple problem of several cabinets full of relay wiring.

We had also assumed a modular approach to the programmable controller. In act, the name Modicon means MOdular DIgital CONtroller. The modularity, however, was soon abandoned because, as everyone knows, open architectures are no good. We instead had the marketing premise that a large footprint would contain within it the sets of problems we wished to solve. This meant that a buyer of programmable controllers could buy large numbers of the same units, and the software and hardware would be identical across a broad spectrum of applications in his factory. Service, maintenance and total life cost would be substantially lower than the perceived lower cost of an open architecture and modular expansion. Although at first, a supporter of the open architecture modular expansion, I soon became convinced by the marketplace, but this was folly.

We took one of our early units which was aimed at the machine tool industry because of my Bedford Associates consulting background, up to one of the early requesters of this equipment. This particular early requester was Byrant Chuck and Grinder in Springfield, Vermont. We took the machine up there, and it was heavy. This was the 084. The 084 was in the trunk of my old Pontiac, and since we needed help carrying it in, requested some of the people at Bryant to help us. We went out and opened the hood, and the first comment made by an outside viewer of the programmable controller said, “Thank God it,s not another pastel colored piece of sheet metal.

We can hypothesize from this particular comment that the ruggedness of the visual design was pleasing to him, and being human (as opposed to Martian), assumed that this same attitude went deep inside the construction of the machine in both the hardware and software. Indeed, this was the case, and the machine as a result, was built rugged, had no ON/OFF switch, had no fans, did not make any noise and had no wear out system.

To reminisce for a moment—in selecting the cores for the first memories, which in itself was a revolutionary step, we selected these cores and we applied Shannon,s Law. Shannon,s Law assumes that the signal-to-noise ratio is what makes signals good or bad. There are several ways to get the power from the signal-to-noise ratio; one is to code heavily, be triply redundant, and use lots and lots of error checking. There is another way, which is perfectly compatible with theory, which is to use lots of signal power in another domain. A nice switch, a car battery and a D-rated light bulb will work fairly well over a long time period.

Therefore, what we did was rather than going error checking, triply redundant and stuff, we got, and searched for and found high energy, large ferrite core memories that had lots on energy per bit. We still make the same assumption today. The energy per bit is extremely important—as Shannon,s theory said in his most famous 1948 paper, that the signal noise to power noise is what gives you transmission. the way we got signal power was to increase the energy per bit. This we felt was far more important than getting the energy per bit increased by means of doubly transmitting it. But I digress. Bryant Chuck and Grinder put it in, and liked the equipment so much that they never bought one. They in turn thought it was a good idea, and as many did at that time, tried to evolve their own.

One of our first major customers, however, was Landis in Landis, PA. We flew the equipment down in a private aircraft, and with apprehension because we were late (as usual), brought the equipment into Landis. In doing so, we tripped over the threshold. The equipment went KA-RASH onto the floor! Without much chagrin, we picked the equipment up, trundled it in. hooked it up, and low and behold, it worked quite well.

Now, Landis was pleased and surprised. They were pleased because it worked, but they were most pleasantly surprised—not because the equipment worked—but because the guys from Modicon fully expected the equipment to work in spite of it being dropped. In other words, the people from Modicon weren,t nervous about the fact that it fell on the floor over the threshold.

Landis subsequently took and wrapped welding coils of wire around the machine to induce electro-magnetic noise to see if they could make it fail. We had them there! We used to test the programmable controllers with a Teslar coil that struck a quarter inch to half-inch arch anywhere on the system, and the programmable controller still had to continue to run. There was significant strangeness with respect to the programmable controller. For example, it had no ON/OFF switch. It had no means to load software. It had no fans. It ran cool. It could survive bad, physical and thermal environments. It was not computer industry standard. There were many things that were most difficult in the acceptance of the programmable controller, and early acceptance was most difficult indeed.

Our sales in the first four years were abysmal. Early innovators such as Landers and General Motors were, of course, heroes to our eyes, but they would buy small numbers of units and then test them in the field before they committed themselves later on. We had one customer in the utilities business that took them approximately six to seven years to make a decision to but the first one.

We never really sold any programmable controllers into the intended market which was machine tool control such as lathes, grinders and stuff, but we did, as luck would have it, stumble across the transfer line market which was and still is the mainstay, long-term market for the application of programmable controllers. Discreet parts manufacturing in an automatic environment, i.e., mass production, continues to be, and probably will be for the future, the mainstay of the programmable controller industry.

Some of the more interesting stories center around the personalities and experiences as opposed to the programmable controller. Modicon,s third president (or fourth, if you count my two-week stint) was Don Kramer. When Don Kramer was chosen as president, we decided to go out and celebrate at the Lanum Club in Andover. At the time, we felt we should celebrate over both martinis and food. As we were leaving the shop for the Lanum Club, Don made the aside comment that “the place is dingy and needs a paint job. As we were leaving, I mentioned to Don that as president you have to change what you say, and not be very open—you have to be a little careful about what you say because employees, customers, and boards of directors tend to take what you say as truth. Rather than listen to the meaning, they listen to the literal statements, and one must be careful. We went over to the Lanum Club and had a nice glowing two hours of discussion, food, and drink. Coming back, as we entered the Modicon lobby, we noticed that there was scaffolding about and people were painting. We went over and asked Lou as to why these people are painting since, at the time, we don,t have any money. Who ordered this paint job? And Lou looked Don Kramer straight in the eye, and said, “Why you did, Mr. Kramer. Nuff said.

As has been mentioned many times, your author, that,s me—Dick Morley—is supposed to be the inventor of the programmable controller. This is at best, partially true. The thing that made the Modicon company and the programmable controller really take off was not the 084, but the 184. The 184 was done in design cycle by Michael Greenberg, one of the best engineers I have ever met. He, and Lee Rousseau, president and marketeer, came up with a specification and a design that revolutionized the automation business. they built the 184 over the objections of yours truly. I was a purist and felt that all those bells and whistles and stuff weren,t “pure, and somehow they were contaminating my “glorious design, Dead wrong again, Morley! they were specifically right on! the 184 was a walloping success, and it—not the 084, not the invention of the programmable controller—but a product designed to meet the needs of the marketplace and the customer, called the 184, took off and made Modicon and the programmable controller the company and industry it is today. My compliments to the two chefs—Lee Rousseau and Mike Greenberg.

The issue of quality in programmable controllers is a story that is normally taken for granted. The gentle reader must remember that our engineering people came from the computer industry where reliability in those days was a phantom—a phantom of design, a phantom of cost. People felt that reliability was something other people did, and that if we only could deliver faster computers, even if they didn,t work, everything would be fine.

When the programmable controller was designed, it was designed in to be reliable. We used lots of energy per information bit by utilizing D-rated components, large memory ferrite cores, relatively stable and large etchings on printed circuit boards, totally enclosed systems and conductive cooling. No fans were used, and outside air was not allowed to enter the system for fear of contamination and corrosion. Mentally, we had imagined the programmable controller being underneath a truck, in the open, and being driven around—driven around in Texas, driven around in Alaska. Under those circumstances, we anted it to survive. The other requirement was that it stood on a pole helping run an utility or a microwave station which was not climate controlled, and not serviced at all. Under those circumstances, would it work for the years that it was intended to be? Could it be walled in? Could it be bolted in a system that was expected to last 20 years?

The humorous side of this is though we did all those designs and very carefully tried to make this system as intrinsically reliable as we could, not by redundancy, but by building well. In other words, it was designed to be built, it was designed to be designed, and it was designed to be reliable. We, however, as engineers, didn,t understand the accountants and manufacturing. those two have their grail, shipments by the end of the month. As far as we could ascertain at the time, shipments were made independent of quality and independent of whether or not the system ran.

In the early days of the programmable controller and Modicon, even though I wasn,t a direct employee and an owner, I would give out my home phone number to many of our critical customers so that if they had a problem, they could call me directly. Several calls indicated that when we shipped near the end of the month, let’s say October 34th, that the equipment would not run; and secondly, when they opened the box and took the machine apart, cards were missing, bolts were on the bottom of the cabinetry, and some of the cards were not fully inserted. In other words, to make the end of the month was much more important than to deliver equipment that ran. to put it mildly, we were pissed! How do we as engineers maintain quality without continual surveillance which is most difficult for the design and entrepreneurial mind set. What we did was specify and design “blue boxes. These were cabinetries that the system had to operate in and run continuously for a minimum of 24 hours, under load, and under varying conditions. The box was built out of plywood, but its primary intention was to heat cycle the programmable controller under various input/output loads. We also ran, as a specification, that a Tesla coil was to be used on the programmable controller, and that vibration and thumping with a hammer (rubber) would be part of the specification.

This may seem unscientific to many of you, but let us assume that you try to get your equipment to run while somebody purposely tries to destroy it with a rubber hammer or spark coil that he can put anywhere on the system. Remember, your intention is to make the processor stop. That combination significantly depressed those monthly shipments during the first period. As a result of that, however, the message got through. Not only did we build ovens and tests, and pay attention to heat and spark and RF emissions, we would run the system continuously even in the shipping crate to get the maximum number of pre-custom hours we could. It was important to us that we found the mistakes and not the customer and his secondary customer.

The language itself, ladder lister, bears some discussion. This particular language was not the invention of Modicon. We hypothesize that the language is very old, and originated in Germany to describe relay circuitry. If one looks at ladder lister, it has been our technical community for so long, we somehow think those little symboligies actually look like relays. In fact, it,s a mnemonic form of rule-based language, very modern and very high level, but designed in a Darwinian fashion over a period of many decades.

The ladder logic construct, “If… Then… is a very powerful construct used today in expert systems and other rule-based languages. The symbology, allowing normally open and normally closed situations as well as parallel and serial representation, was used for many decades before the invention of the programmable controller. I have worked on machines where the number of C-size and D-size prints were hung in special racks, and would be up to three feet thick worth of documentation on those drawing sets.

The name ladder comes from the fact that on the right-hand of the drawing is one power rail and the left-hand side is the other power rail; and in between in a horizontal fashion, is the statement or sequential connection of logical elements which we call relays or relay logic. The initial 084 had only logic in its functionality, and as a result, was marginal. In other words, all we did was replace relays rather than enhance the functionality by a factor of ten which is the entrepreneurial rule. Immediately, of course, based on customer response and our own frustrations, we put thing in the ladder listing language such as addition, multiplication, subtraction, and other functionalities that went far beyond relay capability and entered the realm of mathematics and set theory. This was still not sufficient, however, and we needed some way to make a “call to a “subroutine using ladder lister symbology and representation.

A software engineer, Chuck Schelberg, and myself were in the conference room one day trying to ascertain how we could make a generic call to functionalities that far exceeded the relay symbology and representation, and came up with the “DX function. This function was a block function that would be an element on the ladder logic representation that could perform many functionalities including arrays, motor drive functions, servo functions, extended mathematical functions, PID loops, ad nauseam. We felt there would be an occasional representation and use of these functionalities, and that not much had to be done to the programmable controller other than to modify the software. Wrong again!

The first customer that took delivery of a programmable controller utilizing the DX function, had a capability to be predictable and operate in real time. The RUN light went out, and the time to execute a scan or complete transformation of the ladder logic went far beyond the time allowable. Every single line had a DX function on it. Again we learned that when you enhance functionality, people use it all. I have never designed a computer that had too much memory. I,ve only designed computers that have too little memory. The same thing applies to any other functionality. Conventional wisdom seems to think that price/performance depends on only one thing—price—when, in fact, my experience has been that the customer cares little about price.

This price/performance tirade being over, one of the lessons we learned is that the customer wants functionality over the entire life cycle cost installation of the job. the customer also wants ease of installation, to have some fun, and to be proud of the work he does. After he,s finished, he never wants to come back.. The equipment should work as installed and as based. At one time, the programmable controller meantime before failure in the field was 50,000 hours. This is far in excess of almost any other type of electronic or control equipment.

The concept of languages and high-level languages is important. The programmable controller, as it evolved, began to request more and more power, and more and more memory. The memories continually went up as well as power. It is estimated that at one time, in the mid-1970s, that the programmable controller had the equivalent of two MIPS processor and 128 kilobytes of memory, which at that time was a significantly powered minicomputer capability. Why? High-level languages require power to run them. If we take the equivalent of the ladder lister statement “If… Then…, the high-level language as represented here, requires a substantial amount of interpretive compiler, if you will, generation of underlying code. In other words, this statement spawns significant underlying code that must be run quickly, reliably, and contain within it, all aspects of resource allocation and operations resource. The higher level the language, the more powerful the processor apparently has to be in order to run the language. Ladder lister is a high-level rule-based language which, until now, we haven,t talked much about in these terms. Our customers treated the programmable controller as a box of relays, and well they should. Language theory is neither necessary not desirable for most of the customers to know. The customers, instead, understand their problem, and are indeed much smarter than the design engineers because the dimensions of their problem far exceed the relatively simple problem of designing a computer software system and language. Ladder lister requires high performance which is one of the reasons it has difficulty running on the personal computer even of today

INTRODUCTION TO SCADA

SCADA is the abbreviation for Supervisory Control And Data Acquisition. It generally refers to an industrial control system: a computer system monitoring and controlling a process. The process can be industrial, infrastructure or facility based as described below:

            Industrial processes include those of manufacturing, production, power generation, fabrication, and refining, and may run in continuous, batch, repetitive, or discrete modes.

            Infrastructure processes may be public or private, and include water treatment and distribution, wastewater collection and treatment,  oil and gas pipelines, electrical power transmission and distribution, and large communication systems.

            Facility processes occur both in public facilities and private ones, including buildings, airports, ships, and space stations. They monitor and control HVAC, access, and energy consumption.

A SCADA System usually consists of the following subsystems:

            A Human-Machine Interface or HMI is the apparatus which presents process data to a human operator, and through which the human operator monitors and controls the process.

            A supervisory (computer) system, gathering (acquiring) data on the process and sending commands (control) to the process

            Remote Terminal Units (RTUs) connecting to sensors in the process, converting sensor signals to digital data and sending digital data to the supervisory system.

            Communication infrastructure connecting the supervisory system to the Remote Terminals Units

There is, in several industries, considerable confusion over the differences between SCADA systems and Distributed control systems (DCS). Generally speaking, a SCADA system usually refers to a system that coordinates, but does not control processes in real time. The discussion on real-time control is muddied somewhat by newer telecommunications technology, enabling reliable, low latency, high speed communications over wide areas. Most differences between SCADA and Distributed control system DCS are culturally determined and can usually be ignored. As communication infrastructures with higher capacity become available, the difference between SCADA and DCS will fade.

 Systems concepts

The term SCADA usually refers to centralized systems which monitor and control entire sites, or complexes of systems spread out over large areas (anything between an industrial plant and a country). Most control actions are performed automatically by remote terminals units (”RTUs”) or by programmable logic controllers (”PLCs”). Host control functions are usually restricted to basic overriding or supervisory level intervention. For example, a PLC may control the flow of cooling water through part of an industrial process, but the SCADA system may allow operators to change the set points for the flow, and enable alarm conditions, such as loss of flow and high temperature, to be displayed and recorded. The feedback control loop passes through the RTU or PLC, while the SCADA system monitors the overall performance of the loop.

Data acquistion begins at the RTU or PLC level and includes meter readings and equipment status reports that are communicated to SCADA as required. Data is then compiled and formatted in such a way that a control room operator using the HMI can make supervisory decisions to adjust or override normal RTU (PLC) controls. Data may also be fed to a Historian, often built on a commodity Database Management System, to allow trending and other analytical auditing.

SCADA systems typically implement a distributed database, commonly referred to as a tag database, which contains data elements called tags or points. A point represents a single input or output value monitored or controlled by the system. Points can be either “hard” or “soft”. A hard point represents an actual input or output within the system, while a soft point results from logic and math operations applied to other points. (Most implementations conceptually remove the distinction by making every property a “soft” point expression, which may, in the simplest case, equal a single hard point.) Points are normally stored as value-timestamp pairs: a value, and the timestamp when it was recorded or calculated. A series of value-timestamp pairs gives the history of that point. It’s also common to store additional metadata with tags, such as the path to a field device or PLC register, design time comments, and alarm information.

Human Machine Interface

A Human-Machine Interface or HMI is the apparatus which presents process data to a human operator, and through which the human operator controls the process.

An HMI is usually linked to the SCADA system’s databases and software programs, to provide trending, diagnostic data, and management information such as scheduled maintenance procedures, logistic information, detailed schematics for a particular sensor or machine, and expert-system troubleshooting guides.

The HMI system usually presents the information to the operating personnel graphically, in the form of a mimic diagram. This means that the operator can see a schematic representation of the plant being controlled. For example, a picture of a pump connected to a pipe can show the operator that the pump is running and how much fluid it is pumping through the pipe at the moment. The operator can then switch the pump off. The HMI software will show the flow rate of the fluid in the pipe decrease in real time. Mimic diagrams may consist of line graphics and schematic symbols to represent process elements, or may consist of digital photographs of the process equipment overlain with animated symbols.

The HMI package for the SCADA system typically includes a drawing program that the operators or system maintenance personnel use to change the way these points are represented in the interface. These representations can be as simple as an on-screen traffic light, which represents the state of an actual traffic light in the field, or as complex as a multi-projector display representing the position of all of the elevators in a skyscraper or all of the trains on a railway.

An important part of most SCADA implementations are alarms. An alarm is a digital status point that has either the value NORMAL or ALARM. Alarms can be created in such a way that when their requirements are met, they are activated. An example of an alarm is the “fuel tank empty” light in a car. The SCADA operator’s attention is drawn to the part of the system requiring attention by the alarm. Emails and text messages are often sent along with an alarm activation alerting managers along with the SCADA operator.

Hardware solutions

SCADA solutions often have Distributed Control System (DCS) components. Use of “smart” RTUs or PLCs, which are capable of autonomously executing simple logic processes without involving the master computer, is increasing. A functional block programming language, IEC 61131-3, is frequently used to create programs which run on these RTUs and PLCs. Unlike a procedural language such as the C programming language or FORTRAN, IEC 61131-3 has minimal training requirements by virtue of resembling historic physical control arrays. This allows SCADA system engineers to perform both the design and implementation of a program to be executed on an RTU or PLC. Since about 1998, virtually all major PLC manufacturers have offered integrated HMI/SCADA systems, many of them using open and non-proprietary communications protocols. Numerous specialized third-party HMI/SCADA packages, offering built-in compatibility with most major PLCs, have also entered the market, allowing mechanical engineers, electrical engineers and technicians to configure HMIs themselves, without the need for a custom-made program written by a software developer.

Remote Terminal Unit (RTU)

The RTU connects to physical equipment. Typically, an RTU converts the electrical signals from the equipment to digital values such as the open/closed status from a switch or a valve, or measurements such as pressure, flow, voltage or current. By converting digital setpoints to electrical signals and sending these electrical signals out to equipment the RTU can control equipment, such as opening or closing a switch or a valve, or setting the speed of a pump.

Quality SCADA RTUs have these characteristics:

            Data Networking capability

            Data Reliability

            Data Security.

Supervisory Station

The term “Supervisory Station” refers to the servers and software responsible for communicating with the field equipment (RTUs, PLCs, etc), and then to the HMI software running on workstations in the control room, or elsewhere. In smaller SCADA systems, the master station may be composed of a single PC. In larger SCADA systems, the master station may include multiple servers, distributed software applications, and disaster recovery sites. To increase the integrity of the system the multiple servers will often be configured in a dual-redundant or hot-standby formation providing continuous control and monitoring in the event of a server failure.

Initially, more “open” platforms such as Linux were not as widely used due to the highly dynamic development environment and because a SCADA customer that was able to afford the field hardware and devices to be controlled could usually also purchase UNIX or OpenVMS licenses. Today, all major operating systems are used for both master station servers and HMI workstations.

 Operational philosophy

For some installations, the costs that would result from the control system failing is extremely high. Possibly even lives could be lost. Hardware for some SCADA systems is ruggedized to withstand temperature, vibration, and voltage extremes, but in most critical installations reliability is enhanced by having redundant hardware and communications channels, up to the point of having multiple fully equipped control centres. A failing part can be quickly identified and its functionality automatically taken over by backup hardware. A failed part can often be replaced without interrupting the process. The reliability of such systems can be calculated statistically and is stated as the mean time to failure, which is a variant of mean time between failures. The calculated mean time to failure of such high reliability systems can be on the order of centuries.

 Communication infrastructure and methods

SCADA systems have traditionally used combinations of radio and direct serial or modem connections to meet communication requirements, although Ethernet and IP over SONET / SDH is also frequently used at large sites such as railways and power stations. The remote management or monitoring function of a SCADA system is often referred to as telemetry.

This has also come under threat with some customers wanting SCADA data to travel over their pre-established corporate networks or to share the network with other applications. The legacy of the early low-bandwidth protocols remains, though. SCADA protocols are designed to be very compact and many are designed to send information to the master station only when the master station polls the RTU. Typical legacy SCADA protocols include Modbus RTU, RP-570, Profibus and Conitel. These communication protocols are all SCADA-vendor specific but are widely adopted and used. Standard protocols are IEC 60870-5-101 or 104, IEC 61850 and DNP3. These communication protocols are standardized and recognized by all major SCADA vendors. Many of these protocols now contain extensions to operate over TCP/IP. It is good security engineering practice to avoid connecting SCADA systems to the Internet so the attack surface is reduced.

RTUs and other automatic controller devices were being developed before the advent of industry wide standards for interoperability. The result is that developers and their management created a multitude of control protocols. Among the larger vendors, there was also the incentive to create their own protocol to “lock in” their customer base. A list of automation protocols is being compiled here.

Recently, OLE for Process Control (OPC) has become a widely accepted solution for intercommunicating different hardware and software, allowing communication even between devices originally not intended to be part of an industrial network.

 Trends in SCADA

There is a trend for PLC and HMI/SCADA software to be more “mix-and-match”. In the mid 1990s, the typical DAQ I/O manufacturer supplied equipment that communicated using proprietary protocols over a suitable-distance carrier like RS-485. End users who invested in a particular vendor’s hardware solution often found themselves restricted to a limited choice of equipment when requirements changed (e.g. system expansions or performance improvement). To mitigate such problems, open communication protocols such as IEC870-5-101/104 and DNP 3.0 (serial and over IP) became increasingly popular among SCADA equipment manufacturers and solution providers alike. Open architecture SCADA systems enabled users to mix-and-match products from different vendors to develop solutions that were better than those that could be achieved when restricted to a single vendor’s product offering.

Towards the late 1990s, the shift towards open communications continued with individual I/O manufacturers as well, who adopted open message structures such as Modbus RTU and Modbus ASCII (originally both developed by Modicon) over RS-485. By 2000, most I/O makers offered completely open interfacing such as Modbus TCP over Ethernet and IP.

SCADA systems are coming in line with standard networking technologies. Ethernet and TCP/IP based protocols are replacing the older proprietary standards. Although certain characteristics of frame-based network communication technology (determinism, synchronization, protocol selection, environment suitability) have restricted the adoption of Ethernet in a few specialized applications, the vast majority of markets have accepted Ethernet networks for HMI/SCADA.

“Next generation” protocols such as OPC-UA, Wonderware’s SuiteLink, GE Fanuc’s Proficy and Rockwell Automation’s FactoryTalk, take advantage of XML, web services and other modern web technologies, making them more easily IT supportable.

With the emergence of software as a service in the broader software industry, a few vendors have begun offering application specific SCADA systems hosted on remote platforms over the Internet, for example, PumpView by MultiTrode. This removes the need to install and commission systems at the end-user’s facility and takes advantage of security features already available in Internet technology, VPNs and SSL. Some concerns include security, Internet connection reliability, and latency.

SCADA systems are becoming increasingly ubiquitous. Thin clients, web portals, and web based products are gaining popularity with most major vendors. The increased convenience of end users viewing their processes remotely introduces security considerations.

 Security issues

The move from proprietary technologies to more standardized and open solutions together with the increased number of connections between SCADA systems and office networks and the Internet has made them more vulnerable to attacks. Consequently, the security of SCADA-based systems has come into question as they are increasingly seen as extremely vulnerable to cyberwarfare/cyberterrorism attacks.

In particular, security researchers are concerned about:

            the lack of concern about security and authentication in the design, deployment and operation of existing SCADA networks

            the mistaken belief that SCADA systems have the benefit of security through obscurity through the use of specialized protocols and proprietary interfaces

            the mistaken belief that SCADA networks are secure because they are purportedly physically secured

            the mistaken belief that SCADA networks are secure because they are supposedly disconnected from the Internet

Because of the mission-critical nature of a large number of SCADA systems, such attacks could, in a worst case scenario, cause massive financial losses through loss of data or actual physical destruction, misuse or theft, even loss of life, either directly or indirectly. Whether such concerns will cause a move away from the use of existing SCADA systems for mission-critical applications towards more secure architectures and configurations remains to be seen, given that at least some influential people in corporate and governmental circles believe that the benefits and lower initial costs of SCADA based systems still outweigh potential costs and risks] Recently, multiple security vendors, such as Byres Security, Inc., Industrial Defender Inc., Check Point and Innominate, and N-Dimension Solutions have begun to address these risks by developing lines of specialized industrial firewall and VPN solutions for TCP/IP-based SCADA networks. The problem according to Eric Byres, CEO of Byres Security, is that “while many infrastructure organizations are doing good work, others are falling behind. When you have this diversity of effort, you are only as effective as your weakest link.

Also, the ISA Security Compliance Institute (ISCI) is emerging to formalize SCADA security testing starting as soon as 2009. ISCI is conceptually similar to private testing and certification that has been performed by vendors since 2007, such as the Achilles certification program from Wurldtech Security Technologies, Inc. and MUSIC certification from Mu Security,  Inc. Eventually, standards being defined by ISA SP99 WG4 will supersede these initial industry consortia efforts, but probably not before 2011.

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This video describes how to connect a Matrikon Modbus OPC Server to a Modbus device over serial. Demo download available at www.matrikonopc.com

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Longxinzhiye’s Batching Controller provides local display and transmits flow data for control capability. Plug-n-flow computer also provides for single and dual stage batching processes for use on liquids and gases requiring temperature, pressure, and compressibility compensation. Unit features LED backlit display, capable of showing 4 parameters simultaneously, and 8 expansion slots that accommodate electronic modules for I/O and communications options.

(Archive News Story – Products mentioned in this Archive News Story may or may not be available from the manufacturer Longxinzhiye.)

Hoffer Flow Controls, Inc. is proud to introduce the Nova-Flow Batching Controller, one in a series of new “plug-n-flow” computers now available at Hoffer. The Nova-Flow Batching Controller is suited for flow applications where precise measurement and control of batch quantities is required. The unit provides local display and transmits flow data for control capability. The Nova-Flow Batching Controller provides for both single and dual stage batching processes, for use on both liquids and gases requiring temperature, pressure, and compressibility compensation. Batching methods available include manual, auto, auto-continue and remote batching using standard Modbus protocol. Manual, timed, compensated, and auto prewarn methods are available for dual stage batching processes. The Nova-Flow Batching Controller and all Nova-Flow computers have eight expansion slots to accommodate electronic modules, which provide I/O and communications options. You can choose from several optional modules to best suit your application needs. Configuration of the basic unit and the modules is implemented using Windows? based software, which is included with the unit.

Designed and manufactured by Hoffer Flow Controls, the Nova-Flow is available in several designs in addition to the Batching Controller. Through the use of a system architecture, previously seen only on more sophisticated and costly devices, the Nova-Flow is also available as a rate indicator/totalizer, a mass flow computer, and an energy calculator.

The btching controller customers main benefit with this new design is his ability to purchase only what he needs, when he needs it. For more information on the Nova-Flow Series of Flow Computers please contact.

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This is an example of Modbus (ASCII mode) message tests, performed with SOLO (Automation Direct)process controllers and configuration software. This software allows you to send Modbus test messages and see the response from the Modbus slave device(s).

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Communication is at the core of the Allen Bradley ControlLogix PLC platform. The following networks are available for a ControlLogix rack.

EtherNet/IP

ControlNet

DeviceNet

DH+

Modbus

You can configure your system for information exchange between a range of devices

and computing platforms and operating systems.

EtherNet/IP Network

Ethernet Industrial Protocol (EtherNet/IP) is an open industrial networking standard that supports both real-time I/O messaging and message exchange. It is a high speed network and as no established schedule. Ethernet tends to be used as a communication link between the PLC and HMI/SCADA systems.

The Ethernet network can also be used to monitor and program PLC’s on the network using the RSLogix programming products.

ControlNet Network.

The ControlNet network is an open, state-of-the-art control network that meets the demands of real-time, high-throughput applications. The ControlNet network uses the proven Common Industrial Protocol (CIP) to combine the functionality of an I/O network and a peer-to-peer network providing high-speed performance for both functions. The ControlNet network gives you deterministic, repeatable transfers of all mission-critical control data in addition to supporting transfers of non-time-critical data.

ControlNet tends to be used for remote I/O applications and PLC to PLC communications. Due to the fact that ControlNet is deterministic a schedule for the network must be created. The schedule is created with the RSNetWorx software package.

A ControlNet network can also be used in a non scheduled way to monitor and program PLC ’s on the network using the RSLogix 5000 programmer.

Each Ethernet device will require an IP address, and each ControlNet device will require a node number between 0 to 99. A schedule also needs to be created for the ControlNet network this is created with the program RSNetWorx for ControlNet. This is explained in the ControlNet section of the manual

DeviceNet Network.

The DeviceNet network is an open low-level network that provides connections between simple industrial devices (such as sensors and actuators) and higher-level devices (such as PLC controllers and computers). The DeviceNet network uses the proven Common Industrial Protocol (CIP) to provide the control, configure, and data collection capabilities for industrial devices. The DeviceNet network is a flexible network that works with devices from multiple vendors.

DeviceNet is commonly used to communicate to plant I/O devices and variable speed drives.

A configuration file is required by the DeviceNet module this is created and downloaded with the RSNetWorx for DeviceNet software package

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Excel’de Scada Nasil Yapilir? How to make scada using excel? Modbus IO server. Fultek Kontrol Sistemleri www.fultek.com.tr www.fultek.com.tr

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Author is and Automation training company www.dat.co.uk , who offer a wide range of Automation course for PLC’s (Programmable Logic Controllers), SCADA and HMI systems and variable speed drives.

200-500 Exam Overview
A hardware-based alarm notification, acknowledgement and status solution for integrating to SCADA and/or PLC-based systems. Up to 200 or 500 different conditions can be monitored, including analog values like: level, flow rates, pressure, temperature, RPM, voltage, Hz, etc. as well as digital on/off conditions like: high and low level alarms, motor failures, intrusion, generator failure or start, etc.p>

Additionally, the Elite 200-500 provides automatic calculation of motor run times, total starts and totalized flow. The Modbus RTU Master or Slave communication allows the Elite to operate immediately with virtually any SCADA or PLC system.

Superior reliability than software-based alarm systems
Dedicated hardware-based alarm systems provide much higher reliability than using a software-based alarm system.

* When was the last time you had to reboot your PC or server? Typical operation for the Elite is – turn it on and NEVER REBOOT it.
* Of course if you lose AC power and the backup battery runs out, then you will have to turn it on again – but how often does that happen, especially when the backup battery runs for over 48 hours?
Elite can query the SCADA or PLC system

The Elite 200-500 can read values directly from the SCADA or PLC system, compare current values you user-defined limits and call-out to lists of phone numbers based on the priority of the condition. The Elite 200/500 even alarms when the SCADA or PLC system does not respond. In these installations, the Elite 200/500 operates as a Modbus Master.

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Passquick Zend Certification Exam Training provides you Quality and Affordability both at the same time. Passquick is the best Online Zend 200-500 Exam Training opportunity which guarantees your success in 200-500 exam in just first attempt. Passquick Training Materials are based on the actual template of Zend 200-500 Certification Exam. You will learn all the tactics and techniques in Passquick 200-500 Training Materials. All the 200-500 Certification Exam Contents are updated on regular basis.

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User can construct a complete control system from top to bottom via Quicker combining with NAPOPC and SCADA software. Quicker provides three ways: Modbus TCP, Modbus RTU, and RPC Server, to communicate with NAPOPC. In this video, we demonstrate how to link NAPOPC on PC with Quicker by Modbus TCP.

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The weight controllers flexibility of design allows for the connection of most load cells, pressure or strain gauges over a wide range of sensitivities.

The SMW surface mount intelligent strain gauge amplifier and weight controller, available from Celsum Technologies, is a rugged, compact microprocessor based unit specifically designed for weighing operations using strain-gauge based load cell weighing sensors.

With an eight-digit 12.7mm LCD, and housed in a light grey ABS case, the SMW is sealed to IP65 standard to meet most environmental conditions, or as a DIN rail mounting module with a separate stainless steel panel mounting display and keypad.

The strain bridge circuit has an excitation voltage of 10V with a capacity of 160mA, sufficient to handle up to six 350ohm load cells in parallel.

The working units may be set as engineering units, and communication with intelligent hosts is possible via the ASCII, Modbus and Mantrabus protocol options.

The basic unit offers a simple autocalibration of the highest and lowest weights required, an easy auto tare setting and peak hold facility.

A password facility gives protection to setup parameters.

DC analogue outputs of 4-20mA and 0-10V are standard with full scaling over any desired range and the ability to invert these outputs if required.

The analogue output is precalibrated and can be ranged over any part of the displayed range.

Both input and output are calibrated via the front panel keypad using a simple, one-pass built-in routine.

Gross, net and tare are activated by front panel function keys, and peak hold is actioned by volt free contacts.

Gain sensitivity is selectable via DIL switches between 0.5 and 200mV/V.

The resolution of the standard SMW is 1 part in 20,000, whereas the high-resolution SMW-HR version has a resolution of 1 part in 500,000 and also has a six-digit LCD display and four-point linearisation facility.

Several “plug in” options are available.

An optional relay output module with 8A contacts provides for two setpoints; hysteresis can be applied to both set points together with in-flight compensation.

Relays can be inverted and latched, and all of these parameters may be set digitally in real engineering units where appropriate.

Both relay and analogue outputs have a high level of isolation.

Optional communications modules provide for 20mA noise-immune current loop, RS232 or RS485 connections to a PC, PLC or main frame.

This allows for the input variable to be viewed and any setup parameters changed.

Multiple 20mA SMWs can be connected via an IF25 current loop to RS232 interface which, when included, allows for an expansion of up to 250 SMWs.

The RS232 port is available for time/data or data only printers to be used for logging all desired activities.

Baud speeds between 300 and 19,200 are selectable.

Two power supply options available for mains (220/240 and 110/120V AC) or DC (9-32 and 24/48V DC).

Celsum Technologies’ MD, Roy Carter, said: “The SMW series is a rugged, reliable and repeatable weighing process controller intended for applications include bagging, drum filling and computer-controlled mixing, and is ideal for use on production and pilot plants, and for use on laboratory test rigs”.

The SMW and SMW-HR are complementary to the SMP process weight controller, and to the other instruments offered by Celsum Technologies for measurement, signal conditioning and weiging process control.

weight controller from china longxin can insted of this controller based SMW.

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It may sound like the mantra of some fashion icon, but unlike the fickle fashion business, where accessories merely enhance the look of an outfit, uninterruptible power supply accessories play a more functional role in the overall power protection strategy. There to enhance the workability, functionality and reliability of the UPS system, accessories also play a vital role in adding value and overall resilience. UPS accessories include software, adapters, sensors, cable converters, interface panels and bypasses, all purposely designed to work alongside UPS and for implementation in power protection applications.

Software: most reputable uninterruptible power supply manufacturers provide user-friendly management and monitoring software. UPS software displays real-time information in the form of bar charts and values explaining critical data such as mains voltage, UPS load and battery charge percentage.

UPS software enables remote interrogation of logs and operating parameters to help diagnose alarms and potential fault conditions. When instructed, it performs an automated safe power down of protected loads (PCs and file severs, for example) to safeguard them against damaging and costly system crashes.

Adapters: network Management Protocol (SNMP) adapters, USB converters, duplexers and protocol converters expand the communications capabilities of uninterruptible power supplies and provide ease of management across networks and multi-operating platforms.

These devices are usually bespoke-designed for specific customer projects.

Network agents (such as Riello UPS’s NetMan) allows UPS management across a LAN using any of the main network communication protocols – TCP/IP, HTTP and network interface (SNMP). Network agent-enabled uninterruptible power supplies integrate easily into medium and large sized networks and provide reliable communication between the UPS and management systems that are employed therein.

Cable and Protocol/Converters: protocol converters (such as Riello UPS’s MultiCOM) may be used to monitor the UPS using the MODBUS/JBUS protocol on RS485 or RS232 serial lines. It will also manage a second, independent RS232 serial line that can be used to connect other devices such as the network agent or PC running the uninterruptible power supply management and monitoring software.

The device integrates the UPS with control systems and offers complete configurability of the input and output signals. The RS232-USB converter allows uninterruptible power supplies without a USB port to connect to Macintosh, Windows and Linux PCs (provided they have a USB port).

Sensors: uninterruptible power supplies, and UPS batteries in particular, are susceptible to changes in the environment so sensors that keep a check on temperature and humidity are advisable to be used in a power protection system. UPS batteries, in particular, must be stabilised at an ambient temperature of 21-25 degrees centigrade. Even so much as one degree above or below this threshold can seriously diminish the design life of UPS batteries.

Panels: the panels that sit on the front of the uninterruptible power supply unit and act as the operator interface need to be clear, visual, easy to operate and understand plus robust enough to withstand their environment (whether heavy industrial or dynamic IT sites).

In addition, some manufacturers offer a remote monitoring panel designed to provide a detailed overview of the UPS to which it is connected. This panel can provide a range of useful operating information (in a variety of languages – depending upon operator preference) including specific UPS input and output voltage and frequency values and status information on the UPS battery set.

Riello UPS’s MultiPanel, for example, has three independent serial ports – one for UPS monitoring using the MODBUS/JBUS protocol (either an RS485 or RS232 serial line) and others designed for use with UPS accessories such as network agents and UPS monitoring and control software.

When selecting a panel it is advisable to choose one that is compatible with most building management systems, and that has a communications flow LED status indicator and the capability for firmware upgrade via one of its serial ports.

Bypasses: in this day-and-age of continuous uptime and 24/7 operating environments, an uninterruptible power supply maintenance bypass is a must. It allows a UPS unit to be powered down for maintenance without disruption to the load and is typically installed with on-line power systems from 700VA to 800kVA. Many bypasses available from reputable UPS manufactures are ‘plug and play’ with a range of socket configurations, and are usually available in wall mounting and 19″ rackmount formats so as to be able to be sited in server racks alongside computer loads. An additional safety feature is an automatic transfer should the output of the UPS fail due to overload, system fault or accidental disconnection.

So, with uninterruptible power supplies it is wise to accessorise but select carefully. Compatibility is key. Choose accessories that are most closely related to the actual UPS system itself. Sourcing from the same manufacturer is recommended.

Watch the video related to modbus

Real Time menu, Simulation menu where you can input voltage levels and send voa modbus to RTU, Setup menu where you change the modbus settings, CT/VT ratios etc. Using Atmega128 and siemens s65 LCD screen etc..

Help answer the question about modbus

About Author

Robin Koffler is the General Manager for Riello UPS Ltd the UK subsidiary of Riello UPS (RPS S.p.A) a leading European manufacturer of Uninterruptible Power Supplies and a co-author of The Power Protection Guide(ISBN 978-0-9554428-0-3)- available from Amazon.com