A high-speed counter (HSC) is a functional capability within particular PLCs. HSCs count the frequency of the pulse of processes from systems with elements such as high-speed encoders. In these cases, special input modules ensure the count’s accuracy and deliver the output to the system element within the latency criteria that optimizes machine or system uptime to meet throughput requirements. Normal counters are adequate unless the pulses you are counting will arrive faster than 2 times the scan time. HSC Overview and Application An HSC is a select type of counter. Counters used in systems with lower pulse frequencies (CTU/Ds) can be implemented as a software-defined PLC element. Thus, it only exists virtually. The HSC requires a hardware input module that can operate reliably in the harsh environmental conditions experienced on a factory floor. The engineering design is a simple input/output device that uses ladder logic to develop the output signal from the inputs provided. After...
The GE Fanuc Series 90-30 has long been a workhorse PLC for GE automation control systems. Introduced in 1991, the 90-30 series has been a popular choice for industrial control professionals because of its versatility and modularity. By contrast, the RX3i CPU Programmable Automation Controller by GE Automation represents the move toward a more comprehensive view of automation and one that both builds on the foundation laid by the 90-30 series while offering even more advanced features and versatility. GE 90-30 Series General Specifications and Features That the 90-30 series lasted for the better part of 30 years is a testament to its popularity. By offering a platform that addressed space concerns as well as cost effectiveness, the 90-30 has been known for ease of programming and their ability to be operated through a variety of inputs. The versatility of the 90-30 series is due to its large variety of CPUs, and each of the 11 available CPUs can accept multiple expansion modules for...
With the growing complexity and connected nature of today’s manufacturing and warehousing environments, control systems are being asked to do more and more to improve efficiency and performance. When adding or upgrading a control system, the proper selection of the right variable frequency drive (VFD) for your motor is crucial. While there are many options for VFDs from a variety of manufacturers, there are many things to consider when choosing a new VFD. These include motor considerations, VFD selection and how the VFD can or should integrate with PLCs. What Do You Need from the Motor? Before diving into the VFD itself, it is helpful to understand as much information as possible from the motor itself. Most of the critical information is included on the nameplate and should be easily accessible. This information will inform the buyer and provide a foundation for selecting the proper VFD by helping narrow down options for the optimum sized unit. Horsepower – Even though it is not the...
The Allen-Bradley Logix family of controllers is considered the most popular programmable logic controller family in the US. It consists of numerous variants but for this comparison we will look at the ControlLogix, CompactLogix and MicroLogix PLCs. By comparison, Siemens is much more common in Europe where their extensive line of PLCs are used in automation control systems throughout industries. The Siemens PLC equivalents for Allen-Bradley’s Logix family members above are part of the Siemens SIMATIC controller family and consist of the S7-200, S7-300, and S7-400 as direct comparisons. General Differences Before diving into unit by unit comparisons, we can first discuss some general differences between the Allen-Bradley and Siemens PLC lines: Performance – Both Allen Bradley and Siemens PLC groups have similar speeds and reliability. Their outputs are also close in number as well. The main differences in performance comes in their ease of use and how they integrate into control...
Like the other entrants in the MicroLogix series, the MicroLogix 1500 is small and can be expanded to fit a wide range of control and communication requirements. The 1500 is also expandable to 512 I/O points and is the most powerful in the MicroLogix family in terms of capabilities. As an addition to the MicroLogix 1100 and 1200 series family members, The MicroLogix 1500 has three base options with a removable processor and an updateable flash OS. With its numerous embedded as well as expandable I/O, the 1500 is a workhorse within the MicroLogix family. Main differences between the 1500 and other MicroLogix family members include: Central Processing Unit – Perhaps the biggest distinction between the MicroLogix 1500 and the other members of the MicroLogix Family is that the 1500 is a two-part system. One component consists of the controller, of which there are three base models, the 1764-24BWA, the 1764-24AWA and the 1764-28BXB. The second component is the central processing unit...
The MicroLogix 1400 series was designed to be small, versatile and expandable to suit a variety of control and communication needs. These controllers offer EtherNet/IP, as well as online editing of programming. They also feature a larger number of I/O compared to other MicroLogix family members. And the MicroLogix 1400 series can enhance network functionality and offer a range of features to help build a customized control solution for a wide range of applications. As part of a family of small programmable logic controllers, the MicroLogix 1400 offers a step up with an expansion of capabilities over other members in this family. Built upon the successful capabilities of the MicroLogix 1100, the 1400 series offers many of the same features but with a more robust feature set on some functionalities including: Increased I/O – The 1400 increases the embedded digital I/O count from 16 in the 1100 to 32. It also doubles the embedded analog I/O on some versions from the 2 offered by the 1000...
We are living in an ever-connected world. It is expected that by 2025, there will be over 75 billion connected devices worldwide. And while personal gadgets, smart homes and smart cities account a large part of those devices, there is an equally fervent push to digitize and automate factories as well. One estimate states that by the end of 2020, 80% of manufacturing companies will adopt some type of IoT technology. And the same urgency of adoption is taking place in utilities, transportation and logistics. In the industrial, warehousing and utilities sectors, much of this control is aimed at empowering the automation of equipment to perform tasks at a faster, more accurate and more productive rate. And this equipment needs control systems and ever improving control technology to adapt to these new requirements. It is easy to assume that these requirements involve large and complex buildouts connecting an entire factory or enterprise. And while that is certainly the case for larger...
In today’s manufacturing environments, few companies can remain competitive without extensive industrial automation. Automation speeds processes, reduces errors, allows for precision manufacturing and ensures factory level control and maintenance over the system of production. It also reduces operator fatigue by eliminating manual tasks thus improving quality. Just as important as the automation functions are the safety features built into the controllers that drive this automation. These safety features are created by use of safety circuits within the automation control panels themselves and are first and foremost designed to provide safe operation for equipment operators and technicians. Aside from reducing risk of injury to those performing tasks on the equipment, safety circuits within control panels also reduce risk by allowing for safe operation to protect damage to expensive capital equipment and to reduce waste through loss of material caused by equipment malfunction. As a...
The Allen-Bradley Programmable Logic Controllers (PLC) are classified as for large, small, and micro-control system. The ControlLogix PLC series uses powerful processors to provide high performance for large control system. In the late 90s, the ControlLogix PLC was first introduced to the market. This ControlLogix series was a rack based platform, kept the major advantage of the fastest PLC. Rockwell began to use meaningful tag addressing instead of direct addressing on the platform. The 5550 with L1 processers are included in the First ControlLogix platform. Due to technological improvements in memory capacity and processing speed, the First ControlLogix favored the 5560 and L60 processor. The ControlLogix 5570 with improved speed and more memory to replace the 5560. Also the Armor ControlLogix controller is introduced in 5570 production line to extend the standard ControlLogix platform for dust and wash-down protection. For new project design, Rockwell Automation recommends first...
In part 1, we discussed general safety terms and categories and covered the concept of risk. By understanding risk, we can determine a structure for the architecture needed to manage that risk. That structure will result in a controller that accomplishes all the tasks involved with the lowest acceptable risk to equipment and staff. In part 2, we will dig deeper into terms and categories to understand their impact on machine safety. The concept of building this structure is called Functional Safety Engineering. Here, functional safety means that the automation protection protocols correctly operate in response to inputs. According to the International Electrotechnical Commission 61508 (IEC): “Functional safety is the detection of a potentially dangerous condition resulting in the activation of a protective or corrective device or mechanism to prevent hazardous events arising or providing mitigation to reduce the consequence of the hazardous event ”. Functional safety is achieved by...
Recently we discussed selecting a new ControlLogix platform and the questions you need to ask yourself, and the expert you discuss them with, before you choose the right controller. For some, the answer will not be a ControlLogix, but a CompactLogix platform, based on system size and complexity. This article will delve into how to separate out the various versions of this controller line and give you a foundation for the conversation about which CompactLogix controller is best for your application. The CompactLogix line currently comes in a much larger range of options than the ControlLogix. Because of its popularity and the wide range of applications it can serve, there are several legacy versions of the CompactLogix that are still (and will continue to be) supported by the manufacturer. Currently, Allen Bradley offers three families of CompactLogix controllers, the 1768, 1769, and 5069 families. Inside this, the 1769 family is broken down into the L3x controllers and the 5370...
Before we dive into the specifics of this processor selection guide, it is important to bring up a few points about picking a controller. While the controller is the main piece to a control system, the best controller will fail if the remainder of the control system isn’t paired properly with it. The biggest, baddest controllers will cover for a lot of mistakes throughout the rest of your system, but they’ll expose just as many weaknesses as they make up for. This blog post will help you select the highest end family of Allen-Bradley’s controllers, the ControlLogix line. But, just as the article says, please sit down and converse with an expert. Plan the system, design it according to the plan, execute according to the design. With the knowledge you’ll gain from this article and the collaboration with those people who research these things on a daily basis, you’ll have more than a successful implementation, you’ll have a control system that will bestow great benefits upon you for...
1968 – The concept of the PLC was born as the Standard Machine Controller. 1969 – Richard Morely of Bedford Associates launches the Modicon 084 Model, kickstarting the race to refine this new technology. 1970 – Parallel to MODICON was Allen-Bradley, releasing the Bulletin 1774 PLC. This was the first time the tern PLC was used. 1971 – General Electric unveils the first design of their general-purpose programmable controller, Logitrol. 1973 – Bedford Associates upgrades the 084 to the Modicon 184, the first commercial success and the first PLC designed to meet the market’s needs. 1975 – Modicon introduces the Modicon 284, the first controller with a microprocessor and distributed control. 1975 – In the same year, the Modicon 384 is released as the first PLC with digitized process algorithms for continuous control. 1977 – The Modicon brand is sold to Gould Electronics 1977 – Allen-Bradley launches the PLC2- based on the Intel 8080 microprocessor 1979 – Allen-Bradley introduces Data...
With the current trend in machine safety being moving towards integrated control and safety functions, Allen Bradley (like most other major suppliers) offers two versions of its main control platforms, the Logix line of controllers. Based on application size and complexity, facilities will use either the CompactLogix or ControlLogix controller platforms for control. Adding safety features onto these controllers, Allen Bradley offers the Compact GuardLogix and GuardLogix (ControlLogix) functional safety rated controllers. As these controllers are updated and improved, there have been several generations of safety rated controllers. With a future trend towards integrating data, safety, and control into one unit for increased productivity, we will continue to see improvements, both evolutionary and revolutionary. The ControlLogix (1756 family) and CompactLogix (1768, 1769, and 5069 families) Programmable Automation Controllers are the primary controllers in Allen Bradley’s offering. The...
Allen Bradley introduced the Micro 800 family of controllers several years ago, and they are slowly taking over the low-end controller segment for the manufacturer. These controllers are meant for small stand-alone projects, and for OEM’s and machine builders who need a low cost but effective controller. Five series of controllers comprise this family, from the Micro 810 “Smart Relay” to the Micro 870 controller. Each series builds on the previous, with the Micro 820 and 830 series being the smallest of the two (and specialized siblings of each other) and the Micro 850 and 870 including higher functionality and capabilities. All five series in the Micro 800 family have some common benefits. One of the biggest benefits is being able to program and configure the controllers. From the Micro 820 up to the 870, onboard add-on modules allow for additional IO, memory backups, and numerous other higher feature capabilities. Except for the Micro 810, all are capable of some expansion from...
