Maybe you know one piece of equipment that keeps failing until you’re finally ready to replace it. Maybe you rely on a specific technician who knows which equipment causes the most costly and frequent repairs. Or maybe you’re looking for a better way to document your system, plan maintenance, and improve reliability before failures occur.
We can use maintenance data to provide a more structured approach.
Reliability-based metrics provide a way to document systems, plan maintenance intervals, and guide upgrade decisions as part of a structured industrial automation and controls engineering approach. Instead of reacting to failures, they help teams identify issues earlier and allocate maintenance time more effectively.
In this blog, we’ll look at three ways to use reliability-based metrics to:
The best information about your electrical distribution system should be easy to access while filtering out unnecessary detail. The single line diagram is a great place to start, but the diagram used to describe distribution in electrical engineering design often falls short in a few ways.
Rather than only showing how power flows through the system, a reliability-focused single line diagram includes additional details about equipment characteristics.
For example:
While it may be tempting to combine system layout and maintenance data into one document, too much information can create clutter and reduce usability. Separating these views often makes it easier for each audience to find what they need.
For more guidance, IEEE 3006.2 provides examples of maintenance-focused single line diagrams.
Determining when to perform maintenance varies by both equipment type and system criticality. Auxiliary systems with minimal operational impact may require less frequent inspection than critical components.
The goal is to build incremental records over time, tracking equipment condition as it approaches end of life, while increasing inspection frequency as risk rises.
One method of determining frequency can be through combining hazard analysis with statistical methods. an approach often used in industrial control systems reliability planning.
Mean Time to Failure (MTTF), provided by manufacturers or historical data, can be used as a baseline. MTTF values across a distribution path can be normalized and adjusted using safety factors to estimate system-level reliability.
For example:
This approach allows teams to:
IEEE 3006.8 provides additional guidance on reliability calculation methods.
A reliability-focused program doesn’t stop at maintenance; it also informs future upgrades.
Rather than relying on intuition, a calculated method can be developed using load studies, capital planning, and product research as part of a broader power system design strategy, teams can use:
Combined, these inputs help identify trends such as increasing power demand or underutilized capacity within the facility.
For example, load and arc flash studies can reveal areas where demand is growing faster than expected, while other areas may have excess capacity that could be better utilized.
Coordination with capital planning teams can highlight upcoming needs, such as:
Product research can also introduce solutions that:
These strategies are just a starting point for improving electrical distribution reliability and reducing maintenance burden.
There is a wide range of tools, guidance, and software available to support reliability programs. The IEEE 3006 series on Power Systems Reliability provides a strong technical foundation, including guidance on planning, evaluation methods, and data analysis.
For teams looking beyond spreadsheets and basic diagrams, CMMS tools such as Limble or Blue Mountain are often used in industry. However, as with any software, the value depends heavily on the quality of the data being entered.
Improving reliability starts with visibility, structure, and consistency.
If you’re evaluating your current approach to maintenance planning or looking to build a more proactive reliability program, we’d be interested in hearing about your experience and sharing what we’ve seen work across industrial facilities, reach out to our team to continue the conversation.
About the Author
Jeff has a B.S. in Electrical Engineering from Louisiana Tech University. Prior to coming to Hallam-ICS, Jeff had 7 years of experience working in prefab construction for mechanical and electrical buildings and skids. He holds a professional engineering license in multiple states, participates in all phases of the project design from concept through construction, and cooks a mean gumbo.
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About Hallam-ICS
Hallam-ICS is an engineering and automation company that designs MEP systems for facilities and plants, engineers control and automation solutions, and ensures safety and regulatory compliance through arc flash studies, commissioning, and validation. Our offices are located in Massachusetts, Connecticut, New York, Vermont, North Carolina and Texas and our projects take us world-wide.