We found 176 posts about Comparison Guides from DO Supply, a global automation parts
reseller focused on hard-to-find and obsolete industrial automation products.
A crane lowering a loaded hook, an extruder decelerating between batches, a dyno test stand pulling a motor down through its rated speed; all three send energy backward through the drive instead of consuming it. Whether that energy gets dumped as heat or pushed back onto the line depends entirely on how the DC drive was specified in the first place. Getting DC drives right for regenerative duty isn’t about buying the biggest frame size available; it’s about confirming, in order, that the drive can even operate in the right quadrants before anything else on the spec sheet matters. Buy PowerFlex DC Drives Here Start here, because nothing downstream matters if this is wrong. A two-quadrant (2Q) DC drive motors in one direction and dissipates any braking energy as heat; it has no path to send that energy anywhere useful. A four-quadrant (4Q) drive motors and brakes in both rotational directions, and that reversibility is what makes energy recovery physically possible. ABB doesn’t leave...
When an industrial Human–Machine Interface (HMI) reaches the end of its service life, replacing it involves more than swapping a new HMI screen into the existing panel cut-out. The HMI application is intricately linked to communication networks, machine diagnostics, alarms, operator controls, and PLCs. Therefore, selecting an HMI replacement is not simply a hardware upgrade; it’s an engineering decision that requires verifying compatibility with the existing PLC network and supported communication protocols, evaluating mechanical fit and electrical specifications, migrating the HMI application, and testing operator controls. These selection considerations are particularly relevant when migrating from a legacy PanelView Standard terminal to the PanelView Plus series. The migration process primarily involves converting the application, reviewing unsupported features, resizing HMI displays, updating communication pathways, and functional testing. Both Allen-Bradley HMI terminals provide...
Speed control and torque control are the two main operating modes used by servo drives and variable frequency drives (VFDs) to run primary AC and DC electric motors. The drive’s internal control loops govern output voltage, current, and frequency based on the approach chosen under Torque Control vs. Speed Control system topologies. Torque control modulates active stator current to provide precise rotational force independent of speed variations, while speed control prioritizes maintaining the target shaft velocity regardless of load fluctuations. To implement the best control mode, we will analyze this article as Torque Control vs Speed Control, process stability, safety, and energy efficiency; system engineers must examine load characteristics, feedback devices, and mechanical dynamics. Order Allen-Bradley Servo Drive 1398s Here The motor drive operates as a closed-loop velocity regulator in speed control mode, with the inner torque reference being adjusted by the outer control loop...
Industrial automation systems rely on industry-grade Ethernet switches to provide reliable communication among Variable Frequency Drives (VFDs), Programmable Logic Controllers (PLCs), remote I/O modules, HMIs (Human-Machine Interfaces), and other networked devices. Selecting the right Ethernet switch is a key consideration when designing, upgrading, or expanding an industrial network. Industrial Ethernet switches are primarily classified as unmanaged or managed. Unmanaged switches require no configuration and generally provide basic plug-and-play connectivity. These switches are used in small, basic networks that do not need redundancy, traffic control, advanced monitoring, or diagnostic capabilities. Conversely, managed Ethernet switches offer control over network functionality, providing greater visibility. They also support diagnostic protocols, including the Simple Network Management Protocol (SNMP). In addition, various managed Ethernet switch models do support access control...
Motor control comes in all different shapes and sizes depending on its use case and feature set. Soft starters, for example, are a fantastic solution when the goal is to bring a motor up to speed gradually without subjecting your equipment to the sudden shock of an across-the-line start. By gradually controlling the power delivered to the motor during startup, they can reduce starting current, limit mechanical shock, and provide a smoother acceleration. However, they aren’t a fit for every motor application. The biggest limitations usually appear after the motor starts. Once acceleration is complete, a soft starter typically supplies the motor at full line conditions, often through a bypass contactor, and provides far less continuous motor control than a variable-frequency drive. There are also applications where a soft starter adds complexity and expense without providing much benefit. Understanding these situations can make the difference between choosing a controller that fits the...
One of the most important decisions in industrial motor control is choosing the right Variable Frequency Drive (VFD), or AC drive, to match your motor and application requirements. Proper AC drive selection begins with understanding the mechanical load characteristics because the load type determines the current and torque requirements the selected AC drive and connected motor must meet across all operating speeds. An appropriately sized AC drive provides adequate continuous and overload current capability to generate the required motor torque while operating reliably. Selecting an incorrectly configured or improperly sized AC drive often results in insufficient starting or accelerating torque, excessive drive or motor heating, reduced efficiency, nuisance trips, and premature equipment failure. In contrast, an AC drive that is correctly matched to the specified load type helps improve motor performance, operation reliability, energy efficiency, and overall system lifespan. Because of...
When choosing a PLC, the system’s architecture affects all subsequent engineering work, from how control panels are drawn to the cost of maintaining the system over years of service. Most PLCs fall into one of two competing design philosophies: modular architecture, where the I/O, CPU, and power supply are separate elements on a common backplane, or fixed architecture, where all of these are combined in a single housing. Every major PLC vendor offers product lines that follow both designs, and understanding how each platform is laid out helps an engineer pair architecture to application rather than defaulting to whatever solution is already sitting on the shelf. Comparing the five largest control vendors in Europe, North America, and Asia – Rockwell, Siemens, Schneider Electric, Mitsubishi, and Omron – all of which market modular and fixed models side by side – shows which factors vendors weigh when dividing fixed and modular I/O architectures. The real tradeoffs come down not to...
When selecting a soft starter for your motor control application, it helps to know what each setting does and how it affects your motor’s behavior. However, as different modes and features are added to a soft starter, it can be a bit overwhelming to determine the optimal choice for your application. After all, there is kick start, current ramp, torque control, linear acceleration, full-voltage start, and more. Today we will narrow down this list and go over the two more popular starting modes, voltage ramp and current limit start, explain what makes them different, and even why they might be used together. Order SMC Flex Soft Starters Here Before we dive into how these soft starter features work, it helps to first briefly go over what a soft starter is and does. If you would like a much more in-depth explanation and overview, we encourage you to read our full guide to soft starters here . The general idea of a soft starter is to place this device between an induction motor and its...
When it comes to PowerFlex drives, the gap between the most cost-effective model and the most technologically advanced unit is quite significant. From the humble PowerFlex 4M and 520-series controllers offering simple and dependable motor control, to the flagship PowerFlex 755T family built with smart features in mind for demanding applications. Technically speaking, both ends of the lineup are doing the same basic job. They take incoming electrical power and control how it’s delivered to the motor. But that’s like comparing a 20-year-old work truck and a newer, fully equipped heavy-duty model. Sure, both can get you down the road, but one is designed to handle a much wider range of conditions, loads, and specialized tasks. It’s this gap that makes the PowerFlex line interesting to compare. Moving from an entry-level drive to a high-performance model doesn’t just add a few settings or a larger enclosure, but rather more sophisticated motor control, beefed-up hardware, and a suite of...
Automation equipment gets phased out all the time. We see it with PLCs, drives, and everything in between. However, obsolescence doesn’t mean the equipment is unusable or should be replaced immediately. This is the case for the SMC Dialog Plus soft starter family. Discontinued in 2014 as Rockwell phased out the mature product family, the successor to this soft starter family is the SMC-3 , SMC Flex , or the SMC-50 . The question is now whether the SMC Dialog Plus is still worth using or if its newer replacements are a better buy. There are many reasons why someone would want a legacy product over a newer offering. Sometimes it’s just easier to get the same product you know will be reliable and work for your system. Other times the cost of upgrading might not be worth the potential productivity increase of a newer system. Often, a facility needs a direct replacement as soon as possible when their old one breaks. There is no time to fit, program, and upgrade to newer hardware when every...
In a VFD-dominated industrial world, soft starters still have their place in motor control. They are a reliable way to protect your motors, the loads they move, and the systems they’re attached to. On top of that, they fit nicely into a budget-conscious build when a facility doesn’t need the extra features or programming that VFDs offer. Not every soft starter is built for the same job. Some are basic starters designed for simple start-and-stop control. Others are more advanced units with stronger protection features, better diagnostics, communication options, and more control over how the motor starts and stops. Each type has its own advantages, limitations, and best-fit applications. A variable frequency drive, or VFD, is the more common component to pair with a motor for industrial control. VFDs can control motor speed, improve efficiency in variable-speed applications, support advanced diagnostics, and, in higher-end models, offer features such as regenerative operation and...
DC drives continue to play a crucial role in heavy industrial applications that need outstanding starting torque, accurate speed control, and quick dynamic response, even though AC variable frequency drives have significantly increased their market share. DC drive technology is still used in a number of industries, including material handling, elevator systems, crane operations, paper making, and metal processing. Performance capabilities, energy efficiency, hardware complexity, and long-term operating costs are all determined by the basic differences between regenerative and non-regenerative DC drives. This page offers a thorough technical comparison of these drives, backed by up-to-date performance measures and industry statistics. The operational quadrant capability represents the most fundamental distinction between these drive types. Source Regenerative PowerFlex DC Drives Non-regenerative drives are commonly one- or two-quadrant converters. A one-quadrant drive provides motoring...
In the modern age, motor control isn’t as simple as it looks. There’s matching nameplate specifications, determining if the load you’re driving needs certain features like regeneration, or even figuring out if it’s worth futureproofing. With VFDs being so common today, it is easy to assume they are always the better answer. But that’s not always the case. Sometimes, less really is more. If the application only calls for smooth starting and stopping, a soft starter could be the cheapest, simplest, and most cost-effective choice. A soft starter, as the name implies, is a motor controller that gradually and smoothly increases a motor’s speed until its desired RPM, rather than slamming voltage into it all at once. This is a desired feature as its ability to reduce inrush current and limit peak electrical demand on motor start-up reduces mechanical stress on the system and prevents overcurrent scenarios. Source SMC Plus Soft Starters Here To achieve this, soft starters use thyristors, or...
A new installation is not the same as a retrofit project. The selection logic for a ControlLogix processor must take into consideration elements that are absent from a greenfield project, and the risks and constraints are different. A processor must fit into a panel sized for a PLC-5 or SLC 500 chassis, communicate with devices never intended for EtherNet/IP, coexist with existing wiring, and be maintainable by a team that has worked on RSLogix 500 for years. A predetermined set of technical criteria must be followed to make the proper choice. That approach is covered from the start in this article. The first task on any ControlLogix retrofit is documenting the full scale of the legacy system, not just the I/O count, but everything the existing controller manages. A practical first pass is to group the 5580 processors by memory class: 1756-L81E for smaller systems, 1756-L82E or 1756-L83E for moderate retrofits, and 1756-L84E or 1756-L85E for larger PLC-5 migrations, high tag counts...
Conveyor systems serve as crucial circulatory networks in warehouses, airports, mining operations, food processing plants, and manufacturing industries. Well-designed conveyors drastically reduce manual material handling while improving operational efficiency and ensuring consistent output quality. Allen-Bradley PowerFlex drives are essential components of modern conveyor systems, whose performance relies heavily on precise control of the connected motors. PowerFlex drives utilize advanced control modes, including Sensorless Vector Control (SVC), Volts/Hertz (V/Hz), and TotalFORCE technology (available on the PowerFlex 755T series), to deliver high-precision regulation of motor speed and torque. This highly precise motor control enables smooth acceleration and deceleration of conveyor systems, significantly reducing wear and tear on conveyor belts, gearboxes, and bearings by minimizing mechanical shock. Selecting the correct PowerFlex drive helps minimize system downtime, enhance...
