How to upgrade to a high-performance HMI
When beginning a hardware and software upgrade project, look to implement high-performance human-machine interface (H-P-HMI) graphics for greater control of manufacturing processes and systems.
A new industrial age is upon us and with it comes a wave of innovative technology such as machine learning, artificial intelligence (AI), virtual reality (VR) and augmented reality (AR). These leading-edge technologies are adding value to businesses and, even more important, are creating safer work environments. The manufacturing sector is beginning to embrace this next level of automation to improve their processes and upgrade or replace their outdated control systems and software. For many, it is a great opportunity to innovate and not replicate their systems and software.
To leverage the latest technology and ensure manufacturing processes continue to run smoothly, attention should be paid to the human-machine interface (HMI), which is a tool operators use on a daily basis. HMI graphics are used in every aspect of a process control system and are key to getting critical data to the right people at the right time. The move to high-performance HMIs will help improve an operator’s ability to manage operations effectively and increase response time to alarms and other abnormal situations.
Depending on its size and scope, a high-performance HMI upgrade can be fraught with challenges and may require a significant investment in time and resources. However, the benefits realized from a high-performance-HMI far outweigh the upfront investment.
Early HMI design issues
One of the greatest challenges in upgrading legacy HMI revolves around the existing design and converting the screens to a new or different format. In the early days, when control systems became sophisticated enough to have real-time process control graphics, personnel were tasked with developing the graphics (see Figure 1). In most cases, they created them using piping and instrumentation diagrams (P&IDs) and came up with their own set of best practices, trying to determine what “good” looked like. It worked for the most part.
Over the years, however, facilities may have had multiple personnel involved in creating their HMI graphics, which introduced inconsistencies in color and alarms. The graphics sported eye-catching colors but tended to cause operator confusion, making it difficult to see at a glance whether a process was running well or poorly. In addition, graphics were organized by pages, like a book with tabs. Some pages had customizable dropdown lists and others had lists with links to the graphics requiring the operator to select a back button to change displays. Some designs tended to be too simplistic while others were very complex. These displays can be overwhelming for someone not familiar with the overall look and process.
In a sense, low-performance HMI (LP-HMI) graphics were established and many are still in use today. Poorly-designed HMIs, along with poorly-configured process alarming, have often been cited as significant contributors to major industrial accidents.
Establishing graphics standards upfront is key to overcoming these design issues. They help guide the entire process and overall company vision. Today’s high-performance HMI software takes a multilayered approach. Its standards guidelines were created to optimize the end user experience and encourage creating a graphics hierarchy to help establish a sensible graphics flow. With high-performance HMI, information (data) is presented in a way that there is no question as to whether conditions are good or bad. Operators can use multilevel hierarchy displays to navigate quickly to a screen or drill down to an even more detailed display. Dashboards contain an overview with buttons or links that open graphics for more detail on specific areas in a facility.
Operator buy-in for high-performance HMIs
Prior to implementing an high-performance HMI upgrade, it is critical to get operator buy-in. Real resistance comes when trying to implement anything that isn’t pulled from existing layouts or piping and instrumentation diagrams (P&IDs). Operators are comfortable with their traditional graphics and tend to follow the old mindset: “Make it look exactly like the screens that are there.” They are familiar with the old-style drawing layout challenges.
The resistance to change is understandable. For many facilities, operators and engineers have invested a lot of time in how their legacy HMI screens are driven from menus or alarms. They want any new screens to fit the same scheme. Some facilities also have extensive database-driven layouts and object locations, which means it’s not always easy bringing the two together.
Overcoming change starts with proper upfront planning, preparation and training. Understanding the process and how the graphics and objects work is key before starting to fully design screens. Take the time needed to train personnel and start slowly to build some small screens and devices simulated with test programmable logic controller (PLC) code. This process should be basic and quick.
Manufacturers can leverage a high-performance-HMI to develop screen groups, identify common scenarios that need common devices shown and determine how alarms will interact based on various situations. Through upfront testing and training, operators can see first-hand how the HP-HMI software’s multilevel navigation features help optimize and improve processes quickly and more reliably, as well as mitigate safety risks. Finally, involving operators from the start and getting their input makes them a part of the process and lowers resistance to change.
It is important, and possibly the difference between success and failure, to remember a few key points when planning and implementing a high-performance HMI. Personnel often struggle with:
- Too many screens
- Input/output (I/O) overload
- Massive amounts of alarms.
Also note HMI graphics at the process control level are intended to have the look and feel of a control panel. Operators should see the graphics as the means to operate the process, as well as providing the capability to monitor what they are controlling.
A trained facilitator should lead key engineers and operators in a storyboarding session, which is a design process to help define, develop and organize a visual representation of the new high-performance HMI’s graphics layout and hierarchy. Navigation between graphics must be intuitive and instinctive (see Figure 2). This tends to be a multistep process and requires several days for a typical operating console in a manufacturing facility. Once the storyboard is developed, the entire process will help identify the type and number of graphics required. It also reduces extraneous information and graphics on the displays. This is a great opportunity to involve key personnel and get their input.
Other HMI tools and considerations
Other tools and issues to consider include alarm management, visualization tools and read-only remote access.
Alarm management. HMI software and alarm management go hand in hand. The standards and importance of alarm management have inspired improvements in HMI software. Alarm management standards (e.g., ANSI/ISA-18.2) have been developed to address issues with nuisance alarms, alarm floods, alarm tolerances, stagnant alarms and more. Poor alarm systems can be just as bad as not having an alarm system at all.
Vendor-supplied data historian tools now can be configured to include alarming in the tools. Using alarm management software outside the process control network allows the alarm monitoring responsibilities to be dispersed to personnel who are not working directly in the process control areas. For alarms involving non-process critical details, notifications can help the operators focus on the process and more critical alarms.
Visualization tools. Since facility decision makers are spread out among various departments, having access to the process control HMI graphics requires additional process control terminals. However, it is not a safe or efficient practice to use these terminals outside the process area. Instead, using process data historians to capture and record process control data in real time permits this information to be shared and visualized outside the process control network.
Many vendors such as Rockwell Automation, OSIsoft, Wonderware and AspenTech now offer visualization tools packaged with their data historians. These visualization tools allow most of the same functionality of the high-performance HMI graphics tools, making them available to decision makers. Some of the visualization tools are even more complex and offer greater functionality. In fact, some visualization tools available use HTML5, which allows scalability to the graphics, making them available on just about any device. Being able to create HMI graphics using process control data in real time allows for greater visibility throughout the organization.
Read-only remote access. Many of these vendors also offer toolsets that can be used to create graphic displays that are near-exact replicas of the process control systems’ HMI graphics. This allows decision makers outside the process control network the ability to see in real time what the operators are monitoring and seeing. Essentially, this extends the process control graphics in a “read-only” format to the desktops or laptops of anyone within the organization without fear of the process being affected in any way. This read-only view also ensures anyone using the visualization tools for monitoring a process will always have the right version of the graphic.
Currently, with the proper credentials and an internet-connected device, decision makers can look at process control graphics and data from just about anywhere with hand-held devices. For example, R&D facilities are now able to use and monitor graphics outside the process control network as new products, batches or processes are introduced to the manufacturing floor. For years, having R&D involved with new startups required travel to the actual location, adding significant cost to the development process.
Eliminating the danger of altering or controlling a process removes all threats of accidental or intentional manipulations within the process control system. With proper security applied to the replicated graphics, remote personnel will not be able to make changes to the graphic files.
With any high-performance HMI or overall system and software upgrade project, manufacturers must weigh their strategic investment options and plan early to avoid incurring significant cost. Hardware and software upgrade projects require a holistic view and careful, upfront planning that includes long-term costs, maintenance and sustaining services as part of the overall strategy. Before getting started, consider the following:
- Determine where the facility is in terms of automation and process control hardware and software. Understanding the facility’s current capabilities is key to future planning. There may be some cases where the current process capabilities are adequate but not future proof.
- Close consideration must be given to whether the hardware is compatible with the current process control software and the updated software. Hardware must be flexible enough to support future software upgrades. In some cases, HMI software may contain improvements and features that would require significant updates to the process control system graphics. For facilities where the HMI graphics have never been updated to high-performance HMI, a control system upgrade project is a good time to implement the software, identifying any potential system compatibility issues in the early planning stages.
- An automation investment is not a one time and done thing. Hardware being used within the process control system can and will break down and must be replaced. New equipment will likely be too advanced to just install in place of the old equipment. Having a plan or a schedule to continuously improve the process control hardware and software to stay as current as possible will prevent the potential for major issues down the road, keeping costs under control.
- Don’t wait. The longer companies wait to upgrade their process control system hardware and software, the project will be that much more complicated and expensive. Today’s hardware and software continue to evolve with improvements and changes and do not show any signs of slowing down. Carefully choose the direction and vendor that meets the facility’s immediate needs and maintains backwards compatibility. A high-performance HMI upgrade projects can be complicated and take a lot of time and resources to design and develop.
- Turn to hardware and software vendors in addition to the personnel closest to the processes to assist in defining a project. For businesses that lack available resources to implement this type of project, consider consulting an unbiased third-party automation solutions provider who specializes in designing, developing, building, implementing and sustaining systems and high-performance fHMI graphics no matter the type of process control system or software used.
Maverick Technologies is a certified member of the Control System Integrators Association (CSIA) and a CFE Media content partner.
Original content can be found at Control Engineering.