The central objectives of any maintenance program are to extend the life of the equipment, increase facility uptime and improve plant safety
Today’s industrial plants are more advanced and intelligent than ever, with computer-based components and controls that increase efficiency and safety within the plant. These improvements come with a tradeoff. For example, as plants become more complex, it has become increasingly difficult for plant personnel to conduct basic equipment inspections.
At the same time, these smarter plants are designed to modern standards that make them more practical but also less mechanically robust than was the norm years ago. Those overdesigned plants were costly and inefficient, but also robust and reliable. Today’s plants justifiably sacrifice some of that ruggedness for efficiency, but when you consider the increased complexity, use of many different manufacturer’s equipment and the unfamiliarity of onsite staff, third-party testing and maintenance becomes imperative.
While today’s plants are more efficient, more productive and safer than their predecessors, they also require a level of expertise to safely operate and a customized approach to maintain that inhouse resources cannot often address. With that in mind, here are a few things to consider when developing a maintenance and testing program for today’s industrial plants, understanding that the central objectives of any maintenance program are to extend the life of the equipment, increase facility uptime and improve plant safety.
Consider the alternative
As plant managers strive to implement continuous improvement processes that enhance the efficiency and effectiveness of their plant’s throughput, their electrical systems are increasingly required to provide consistent power with limited opportunities for maintenance. The ongoing reliability and integrity of an electrical power system depends on effective maintenance and testing programs that adhere to nationally recognized standards (see Figure 1).
Electrical equipment aging and deterioration is inevitable, but many equipment failures are preventable. An effective electrical maintenance testing program identifies and recognizes factors leading to deterioration and informs strategies to reverse these effects and avoid failures. A well-administered testing program can prevent accidents, save lives, minimize costly breakdowns and reduce unplanned outages. It also can lower insurance premiums that typically are more costly if the facility has an inadequate or marginal maintenance and testing program.
However, preventive maintenance can sometimes be viewed as an inconvenient and an unwanted expense. Plants often have to shut down revenue-generating equipment and operations to conduct tests and perform necessary maintenance. It’s like changing the oil in your car or replacing your tires. No one wants to do it but everyone recognizes the benefits gained from regular maintenance.
The alternative can be substantially worse. Put off that oil change, and eventually you deal with a blown engine. Push the tires too long and risk a blowout or spinout that could prove fatal. Similarly, equipment failure can shut a plant down not just for hours, but for days. Or worse, it could result in serious injury or death of a worker. The cost of maintenance may seem prohibitive but the cost of inaction is often much more expensive in the long run. Simply put, ignoring or delaying equipment testing and maintenance isn’t really a responsible option.
Finding and addressing plant power distribution system issues during a planned outage is a much better return on investment compared to the cost of a plant outage, collateral damage during an equipment failure and the consequences of not properly protecting employees. Insurance companies have long understood these risks and strongly recommend adhering to industry standards and working with an independent testing company that can help customize the right solution for a facility. The recommended solution is a customized, reliability centered electrical testing and maintenance program that includes considerations such as equipment age, equipment operating environment, amount of power system redundancy, known problems with apparatus, equipment no longer supported or considered obsolete by the manufacturer and so on.
Start with standards (but do not end there)
Industry standards provide guidance for maintenance testing and intervals. In the U.S., the National Fire Protection Association (NFPA) 70B-2019: Recommended Practice for Electrical Equipment Maintenance recommends practices for electrical equipment maintenance, and NFPA 70E-2021: Standard for Electrical Safety in the Workplace is a companion standard that addresses safety practices for these types of testing and maintenance activities (see Figure 2). The InterNational Electrical Testing Association (NETA) Standard for Maintenance Testing for Electrical Power Equipment and Systems (NETA MTS 2019) is approved by the American National Standard Institute (ANSI) and provides detailed maintenance inspections and testing requirements by equipment type.
These standards outline procedures and frequencies used to develop a maintenance schedule based on the type of equipment, voltage and ambient conditions. They cover power distribution system components including transformers, circuit breakers, switches, protective relays, switchgear, panelboards, electronic and rotating equipment, bus and cable and are a great resource when starting to develop a maintenance and testing program. These standards also include time-directed recommendations based on the amount of time a piece of equipment has been in operation. Time-directed maintenance is just one of three approaches to an equipment maintenance and testing program. The approaches include, but are not limited to:
- Reactive (also known as “run-to-failure”) maintenance, where repair or replacement work is done only when the equipment no longer functions properly.
- Time-directed preventive maintenance, where tasks are performed on a predetermined interval, regardless of equipment condition.
- Predictive maintenance, where condition assessment tasks are performed and equipment health is monitored or trended such that maintenance tasks can be performed when needed to avoid unacceptable deterioration or drop off in performance.
Reactive maintenance is not recommended. It can cause significant disruption and unwanted expenses. Standards-based, time-directed maintenance is a good start, but there are best practices that go beyond existing standards. The predictive maintenance approach is the most robust and most likely to provide system reliability and avoid failures (see Figure 3). These programs react to results of early tests and account for site-specific conditions, such as temperature, contamination and other variables unique to a given plant.
As a best practice, predictive maintenance includes comprehensive, condition-based maintenance and testing programs that evaluate electrical systems holistically as well as the individual components. Testing on all components should include both electrical and mechanical tests as well as thorough visual inspections. Electrical systems are static, but the insulation in and around electrical components breaks down over time with use as the components age and can compromise both electrical integrity and mechanical operations. In fact, deterioration of insulation is the leading cause of electrical equipment failure in today’s industrial plants. Therefore, a comprehensive electrical maintenance and testing program should include inspections and testing that closely measure the integrity of each component’s insulation system.
Building a testing and maintenance program
We’ve established that today’s industrial plants are more complex than they’ve ever been and that best practices in testing and maintenance go beyond recognized industry standards. With all that in mind, how do you put together the right program for your plant?
First, it is important to understand that one size does not fit all. Know your organization and understand the criticality and environmental conditions in your facilities. Those factors will help determine the type of maintenance program you need, the frequency of testing and corrective actions recommended. Ultimately, an effective maintenance program is one that enhances safety, reduces the probability of equipment failure and extends equipment life. To meet these objectives, start with this three-phase plan:
- System assessment, information review and update: This is the situation analysis, including evaluation of equipment condition and identification of existing or potential issues.
- Maintenance implementation: Taking actions to ensure continued and/or improved equipment operation. These actions take place before conditions worsen to the point repair is needed.
- Selective repair and modifications (life extension services): This is when conditions exist that routine maintenance cannot address. This can include equipment failure of some kind, unacceptable operation or safety hazards. These events can be minimized with a robust maintenance program.
This sort of program ensures the reliability and peak performance of critical electrical assets including transformers, switchgear, circuit breakers, protective relays, switches and other equipment and components. Reliability and performance are directly tied to your facility’s overall performance and profitability.
Regardless of the age of your plant or your operational objectives, a testing and maintenance program is needed to meet the facility’s potential and provide a safe environment for your workers.
Again, today’s plants are more intelligent and complex than ever before, and that means performing these kinds of tests and maintenance requires an increasingly uncommon expertise. That’s why specialized, third-party electrical testing companies take the lead in planning and executing customized testing and maintenance programs. These companies provide independent, unbiased evaluation and testing of electrical equipment and systems and deliver high quality preventive maintenance services using state-of-the-art technology and equipment calibrated in accordance with the National Institute of Standards and Technology (NIST). Bringing in a third-party expert will ensure the accuracy of testing results and allow for more efficient use of inhouse personnel during any unavoidable, time-critical shutdowns.
Additionally, there is value in developing a long-term relationship with an accredited testing company who understands your unique plant environment and can meet your specific testing needs. An organization that can start with a thorough understanding of your equipment and power system and gain knowledge through testing and maintenance over time will be better equipped to handle the unexpected. Longer-term relationships offer other benefits as well, including basic logistics, security and site familiarity.
Bottom line: Testing and maintenance are critical to the performance of your plant and the safety of your workers. With that in mind, there are three truths you should understand about modern maintenance programs:
- Any effective testing and maintenance program must be based on the fundamental idea that maintenance cannot be performed once and then forgotten. It is an ongoing, critical part of a fully functioning, efficient plant.
- Standards are an important starting point and must be followed to ensure worker safety. These standards can vary regionally and are regularly updated to reflect changes in the industry. Maintaining knowledge of these standards and adhering to them can be challenging but is essential to plant safety and compliance.
- Since today’s plants are increasingly complex, partnering with a knowledgeable, independent electrical testing and maintenance firm who understands your unique needs and is familiar with your site is important when developing the right program for your facility.