Temperature Rise as a Common Cause of Power Outages
One of the most common reasons for power outages and primary cause of arc flash incidents is temperature rise from a faulty connection. As equipment ages, faulty electrical connections in low/medium voltage equipment can increase – studies show that poorly maintained equipment is 62% more likely to fail.
Until recently, the accepted or only “best practice” that increases equipment reliability has been a preventative maintenance program in the form of periodic thermal imaging inspections. They are generally annual and typically utilize a combination of an infrared thermal imaging camera and a thermal window.
However, although this is an evolutionary step in relation to Reactive Maintenance, there continues to be a very significant “performance gap” between the perceived levels of protection compared to the actual level of risk mitigation obtained from a Reactive Maintenance approach. Preventive.
Predictive Maintenance
Predictive Maintenance (PdM) is the application of proactive, data-driven maintenance techniques designed to assess the condition of equipment to determine when repairs should be performed.
To plan corrective maintenance before an electrical asset fails, predictive maintenance software employs data science and predictive analytics to predict potential failures and defects. The goal is to schedule maintenance when it is most practical and cost-effective, maximizing equipment life, while preventing equipment from being compromised, and limiting personnel contact with compromised assets.
The basic structure of a predictive maintenance solution typically consists of several components, a decision support system or platform (or DSS) with data collection, storage and processing, asset health assessment, prognostics and condition monitoring.
Preventive maintenance
Preventive Maintenance (PM) is a form of maintenance that regularly checks equipment and other assets to reduce the risk of failure and optimize working conditions.
This proactive maintenance strategy is time-based, also known as strategic maintenance, and includes planned maintenance that can be annual, quarterly, or monthly to streamline planning and implementation. This is typically organized with the help of a computerized maintenance management system, also known as CMMS software, to avoid machine downtime and increase the useful life of assets.
Operating an asset until it breaks down can cost a company up to ten times more in repairs and lost productivity than it would cost a company with a planned preventative maintenance policy.
Difference between Preventive and Predictive Maintenance
The difference between preventive and predictive maintenance is that preventive is routine maintenance or inspection, scheduled at regular intervals, regardless of the condition of the equipment. This often leads to unnecessary costs, while predictive maintenance is only scheduled as needed, based on real-time asset condition. Predictive maintenance, therefore, reduces labor costs and operational downtime, while increasing safety by removing people from risky locations and increasing asset life.
Although factual, the critical issues that create this performance gap situation are often not fully explained or understood.
They include:
- Workers continue to be exposed to risks;
- Annual thermography represents an inspection of less than 1% of operational time, leaving 99% dependent on luck;
- The timing of inspection often does not reflect the most critical operational electrical loads;
- The measurement depends on the abilities of the equipment and operator to correlate with the true internal temperature (so it will never be of uniform quality);
- Data remains independent and unintegrated, rather than dynamically integrated information;
- Infrared transmission rates through a thermal window can deteriorate significantly over time, affecting the accuracy of temperature readings.
Thermal camera manufacturers state that two requirements are essential to obtain accurate temperature data when performing a thermal inspection of electrical equipment.
The first is that the camera must have a direct line of sight to the driver being inspected (thermal windows have varying and deteriorating levels of infrared transmission, therefore not meeting this requirement).
The second requirement is that the conductor being thermally imaged operates with a minimum load of 40% of the design load. For example, a circuit designed for 3kA should operate at a minimum of 1.5kA during an inspection. This is rarely observed by those who perform thermal inspections of electrical equipment and is not known to most equipment owners/operators.
The Maintenance Performance Gap
Fortunately, there is now a way to reduce this “performance gap” and improve protection by continually monitoring and analyzing temperature data, not only identifying but proactively predicting problems arising from faulty connections. Innovative software with intelligence, like Bridgemeter ®, has evolved to provide the “next technological step” of Predictive Maintenance.
With 24x7 real-time monitoring, predictive analytics can detect approximately 70% more failure symptoms before failures actually occur than periodic inspection.
This is achieved through permanently installed temperature sensors specifically designed for thermal monitoring of electrical panels, MCCs and transformers.
Predictive technology using thermal sensors solves many of the critical issues identified above and closes the performance gap, providing greater safety, more reliable operational uptime and better asset integrity.
Rising global demand for IoT devices and related products is also fueling the growth of industrial IoT, or IIoT, as it is known. This requires industrial equipment and machines to have integrated condition monitoring sensors, which acquire condition data 24x7, with an internet connection for subsequent analysis and real-time identification of fault conditions. This allows more efficient maintenance practices to be adopted, enabling considerable benefits over the life of the equipment, which can be delivered as part of the IIoT/digitization of critical electrical infrastructure. These IIoT benefits include:
- Elimination of unnecessary inspections and their associated costs;
- Reduction in preventive maintenance to comply with the equipment manual “as required”;
- Reduction of downtime costs associated with periodic inspection/maintenance;
- Reduced repair/spare parts costs and associated downtime through increased early detection of failure symptoms;
- Increased safety when removing people from risky locations;
- Identification of equipment with better performance for future acquisition decisions;
- OPEX savings due to reduced ongoing periodic inspection/maintenance costs.
This accelerated shift from inspection to continuous asset monitoring is necessary as a greater number of global companies adopt digitalization strategies in the search for greater competitiveness in this new digital world.
Modernizing electrical infrastructure to include innovative technologies such as 24x7 real-time smart monitoring will increase the safety, performance and lifespan of electrical infrastructure through predictive analytics. No matter what type of electrical installation you maintain, a continuous, digital approach to monitoring will provide the most cost-effective and efficient way to ensure your electrical equipment is protected and operating at all times.
Finally, the most opportune time to install predictive monitoring sensors is during scheduled maintenance stops, thus updating the equipment and making it possible to obtain all the benefits of predictive maintenance through Intelligent IIoT, effectively closing the “performance gap” that exists with preventive maintenance.
Modernize your electrical infrastructure with Bridgemeter ® from Above-Net ®. Schedule a consultation today and optimize your equipment with our cutting-edge predictive monitoring:
With information: Exertherm
