Drives programming software: No pain system design, start-up
Inverters, drives, variable frequency drives, motor drives: whatever you call them, engineers understandand accept their performance-enhancing, energy-saving, and motor-protection benefits. That acceptance has led to a proliferation of drives offerings, with much of the hardware based on similar technology resulting in excellent or enhanced quality across leading brands. Engineers considering drives options may want to focus on the ease-of-use tools and features provided by the configuration software as much as the actual hardware. By examining the whole drives package, especially the configuration software, engineers can make a more informed decision that saves time and labor during configuration, commissioning, and start-up.
Like all software, drives configuration software is experiencing rapid evolution, making it easier to use and more powerful. The most profound advancements involve integrating the controller and drive. For networked drives, integration capabilities help lower programming, installation, and overall ownership costs by minimizing the software tools required. This helps users gain faster start-ups, improved accuracy, and easier drive-system maintenance.
Traditionally, adding a drive to a control system meant learning to work with a new software tool and managing separate drive configuration files. By using programming software that integrates the drives and the controller, users have less of a learning curve and can more easily manage the drive and the control system since there is only one software package to purchase and learn.
Reduce risk of mismatch I/O
When installing drives, a major complexity is configuring the settings to synchronize two programming environments. For example, a conflict in the I/O configuration setting can arise when the controller and drive are configured at different times with different tools. In other words, the controller expects one size of I/O while the drive is configured for a different size. This mismatch creates an I/O connection error in the program and can become a nuisance for programmers, typically during system start-up when time can be limited.
In the past, the first phone call to tech support involved troubleshooting to remedy these communication gaps. With integrated drives configuration, users can now configure both sides of the network connection at the same time with one tool, reducing the potential for errors. This capability can be especially beneficial in applications involving a large number of drives, where managing the various configurations can consume an inordinate amount of engineering time and resources.
To ease maintenance and improve access to information, some software saves drive configuration data as part of the controller’s project file and also stores it in the controller. As a result, there is no need to store and maintain multiple files—users need only one file for both the controller and all drive configurations. In the event of a failure, replacement and restoration of the original drive configuration is a much easier process. In some cases, the controller can automatically download the configuration to a replacement drive, further reducing downtime.
No cryptic parameters
Individually programming parameters and tags when configuring drives can be a major challenge. Many controllers store drive information in memory as a contiguous block, where each drive parameter is represented by a physical address or number rather than a descriptive name. Typical tags might read “.data3” or “.data4,” forcing users to constantly refer to user manuals to interpret and document the control program. This tedious task is time-consuming and often must be repeated for each drive in a system.
Engineers installing drives should look for programming software in which a device-specific data structure is created automatically. These data structures can now be represented with descriptive names rather than generic numeric-based parameter addressing schemes used in the past. The data structures also use the proper data types—integer, real, Boolean, etc.—for each parameter, so no manual data type conversion is required by the programmer.
Engineers also should seek software options that provide network I/O drop-down boxes containing all the parameter names. This minimizes the potential for errors when defining various network I/O. Tags can then be created in the control development environment and accessed via an HMI, reducing setup and configuration time. A copy-and-paste programming feature can quickly create additional duplicate drives.
A common problem in many drives installation projects is that multiple engineers are developing different versions of the same code. With numerous code variations, installation and start-up become more tedious and complex. That’s because engineers must check and verify each version—and the specific set of errors used with each code—to confirm a smooth installation. Programming software capabilities, such as user-defined add-on instruction, encapsulate drive-specific operations into a reusable module of code. This reduces the development and validation effort, and promotes consistency among projects since there’s no need to constantly reinvent commonly used control algorithms.
Some software packages further simplify the programming of networked drives with tag generator tools. Users no longer have to worry about I/O mapping and correlating the I/O image with device user manuals. Tag generating tools help save users a significant amount of programming time per device, depending on the complexity of the device.
Start-up wizards for drive commissioning are another key advancement in drives configuration software. Instead of using a linear list editor to navigate through hundreds of parameters, start-up wizards provide a simple step-by-step process. Graphs, images, and descriptive text assist the user through the remaining commissioning process. Besides dramatically reducing drive start-up and commissioning time, wizards can improve setup accuracy by significantly reducing manual configuration with the end device.
Engineers also can enjoy the benefits that device configuration software can offer to simple, hardwired, or stand-alone applications. Drives are just one of many components in a system. For these applications, device configuration software can take what once required several different software configuration tools and wrap it into one software package with a simple catalogue of devices available at the engineer’s fingertips.
Combining a controller with a full suite of compatible components and application development tools—application profile, quick starts, wiring diagrams, and pre-developed HMI screens—can provide engineers with a simplified way to implement common control tasks as part of the machine design. This dramatically improves end-user experience and reduces the risk of potential engineering programming, training, and maintenance nightmares.
Clearly, it’s not just about the hardware anymore. With simplified programming software, engineers can say good-bye to the complicated world of drive-controller integration, and hours of grueling tagging and coding validation. Advancements in programming software capabilities are just the start of integration and interconnectivity capabilities to come.
– Greg Mears is product manager, drives software, Rockwell Automation. Edited by Mark T. Hoske, content manager, CFE Media: Control Engineering, Plant Engineering, and Consulting-Specifying Engineer, firstname.lastname@example.org.
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