We have all experienced that maddening situation. We are midway through a riveting movie or miniseries on television, or just about to save those important edits to a document on our desktop PC, and it happens - power outage. Other times, it is during extreme heat or cold weather and there is no way to know for how long you w
ill have to endure without your air conditioner or heating system. Life as we know it has come to a screeching halt. Our world revolves around that precious commodity - electricity.
We as a society have become so dependent on electrical power that even the briefest disruption can cause mayhem. Among the most important components for the proper functioning of our electrical grid is the transformer which is vital to supplying safe, reliable electricity. The average life span of a transformer ranges from 38 to 40 years. Proper care and inspection are of utmost importance and even more so as they age.
Utility and power companies are very much aware of the growing urgency of keeping systems online and running smoothly. As the demand for electricity has increased exponentially since the beginning of the 20th century, companies have continuously sought out more efficient methods for supplying reliable power to customers with as little disruption as possible.
Utility Maintenance Is Always the First Priority
Depending on its location on the grid, just one failed transformer can result in widespread interruption as well as potential countless dollars of lost revenue for businesses, not to mention huge expenses for electric power companies. Replacement costs for large transformers can range from $1 million to $7.5 million, according to the DOE's "Huge Power Transformers and also the U.S. Electric Grid" record as of April 2014.
The Benefits of Proper Transformer Maintenance
Below are just some of the major advantages to properly maintaining devices, for customers and power companies:
For utility companies, it protects your employees, assets, and business
You make the best use of operation via preventive maintenance
You boost the effectiveness of energy distribution
Monitoring components becomes more efficient when you change from a reactive maintenance strategy to a preventative utility maintenance strategy. Thus, system failures are minimized
You keep electrical circuits functional, increase valuable life span, and reduce emergency situation downtimes which in turn decreases the total cost of operation
Different Approaches to Utility Maintenance
There are four approaches to maintaining all components of the utility grid. Some of these approaches should be implemented during specific situations and not during emergencies.
Reactive Utility Maintenance
This is the most clear-cut of the four methods and permits the equipment to continue to function until it fails. No planned utility maintenance is done to prevent any outages. It is then restored either to its original condition or allowed to perform for a limited time until it can be repaired.
The pros of this strategy are that it is straightforward and involves little to no preparation. However, you should only exercise this strategy with non-critical assets that do not pose risks to safety or consistent operation.
Preventive Utility Maintenance
A recommended approach, the preventative utility maintenance strategy involves planned utility maintenance through regular inspections, equipment maintenance, and part replacement in electrical distribution equipment. The goal for this approach is to minimize breakdowns, extend equipment life, and prevent unforeseen events.
This approach can be broken into three categories of maintenance activity based on complexity: basic, advanced, or exclusive depending on factors such as who is authorized to perform the services and what the activity is.
The preventive approach is a good protection measure where the chance of failure increases with time or usage or there is a known issue that can be prevented with scheduled maintenance.
On-Site Condition Utility Maintenance
This strategy depends on the diagnostics of the equipment and conducts preventive maintenance in conjunction with available on-site diagnostic interventions to analyze the physical condition of the equipment and its operation. This works for situations in which a measurable parameter can accurately indicate potential problems.
Depending on how critical the situation is with the condition of your equipment, you would use the diagnostic intervention process to correct the error, predict future needs for system analysis, or take stock of parts to be replaced. This can also be considered a preventative measure to avoid future outages.
Along with preventative utility maintenance, this is one of the most ideal steps you can take to minimize unscheduled downtime. As a result, you reduce the overall cost and your electrical infrastructure continues to run smoothly and efficiently without incident or hiccups.
As it monitors your equipment's performance with sensor data, it can alert you to possible failures. In doing this, you able better able to manage your resources and replacement parts. In situations where a potential equipment failure could result in significant damage, safety issues, unexpected downtimes, and needless expenditures, this strategy is a lifesaver.
Using Proactive Approaches
Today, power companies are trying to make smarter and economical decisions about when to carry out maintenance on a transformer by taking a proactive approach such as the preventive and predictive strategies described earlier. One such strategy is the preventive method of painting and/or coating of transformers to prevent rusting, corrosion, and other damages inflicted by harsh elements.
Recommended Periodic Inspections
In addition, below are 8 recommended recurrent inspections of a transformer.
1. Control wiring
Check the insulation on the control wiring and make sure it is still intact. Also, check the connecting routes for good insulation.
You must examine the control power supply voltage and compare the readings to the voltage specified on the wiring diagram.
2. Gauge Readings
You should perform this measure one month after the initial energization of the transformer and every year after that.
If any leaks are revealed, they must be fixed immediately to prevent serious damage to the transformer and imminent danger to yours and others’ lives.
3. Cooling fans
You should conduct this measure once per year. Check any cooling fans by setting the control switch to the "manual" position. The fans should work at full speed within 5 seconds and there should be no rattling noises.
4. Fluid dielectric test
This preventive method should be done once a year as well. Insulating fluid is a key component for the cooling of transformers. It is imperative that you check the fluid level gauge and make sure the fluids are at the correct levels. If needed, add more fluid and use only the same fluid currently in the transformer.
Once a year, you should also draw a fluid sample and test its dielectric strength. To avoid inaccurate results, make sure to adhere to the proper methods when sampling the fluid.
5. Paint finish
Once a year, evaluate the paint finish for any damage or weathering that reveals the primer coat or bare metal. Fix any of the paint damage that might be found.
6. Bushing and surge arrester insulators
Make sure that the bushing and the surge arrester insulators are clean. If necessary, clean these surfaces when the transformer is not energized. This should be done once a year.
7. Bushing terminals
This should be conducted one month after the initial energization and yearly after that.
While the transformer is energized and under load, use an infrared scanning device to gauge the terminal temperatures. A dirty or loose connection will cause high temperatures.
8. Examine the gaskets
Visually check all of the gaskets for cracking or other signs of wear and tear. Change worn gaskets required and do not recycle or reuse any old gaskets.
Painting Your Transformers
For optimal use of your utility maintenance time and budget, it is best to have transformer painting services done before your transformer is revealing any significant signs of deterioration. The reason for this is that in any type of transformer painting service, you invest about half of your money towards the surface area cleaning and preparation. Removing the corrosion, oil, faulty coverings, and any other surface impurities is absolutely crucial before you can apply any new paint.
Conversely, procrastinating or stretching out the time between transformer painting services will not save you money, especially in the long run. Every small increment of time that passes increases your costs for surface preparation. Ferrous metal surface area preparation essentially begins at just cleaning and scrubbing and, if needed, progresses to extreme measures such as sandblasting, which can be very expensive.
Taking care of issues at the early cleaning stage will ensure you are getting the most for your maintenance dollar. If you just let it go and allow extensive corrosion to occur, chances are you will end up discarding the transformer at this point and replacing it with a new one which is also extremely costly.
Types of Paint for Transformers
While regular utility maintenance must be conducted to ensure the proper temperatures inside the transformer, painting or coating your transformers can prevent heat and environmental damage to the outside of your transformers. You can't use just any standard paint for your transformer painting services, however. It needs to be a special type of paint that is resistant to heat and other forms of damage.
Heat Resistant Paint
There are different types of heat resistant paint available for transformer painting services developed for various temperatures as follows:
UGAM HEAT RESIST 200 is suitable for a surface up to 170 degrees Celsius or 338 degrees Fahrenheit.
UGAM HEAT RESIST 400 is suitable for a surface from 170 to 350 degrees Celsius (338 to 572 degrees Fahrenheit).
UGAM HEAT RESIST 1200 is suitable for a temperature level between 550 and 1100 degrees Celsius (1022 to 2012 degrees Fahrenheit).
UGAM HEAT RESIST 1800 is suitable for a temperature level between 1100 and 1800 degrees Celsius (2012 to 3272 degrees Fahrenheit).
Using spray paint is also not a good idea for painting transformers since it only protects 50 to 75% of your transformer and radiator surfaces. Spray paint only camouflages any damage and your operations will still be susceptible to electrical failures. This is why many industries specializing in transformer painting services have developed a technique called flow coating.
Flow coating is a very reliable and cost-effective method of performing transformer painting services and is ideal for use throughout the lifespan of the transformer.
This technique of transformer painting services provides full protection of 100% of the transformer and radiator exterior area, and it reaches all parts of the equipment, including those surfaces that are difficult to access.
No dismantling of equipment is needed when applying the flow coating and it is done on-site.
Ideal Colors Used in Transformer Painting Services
When transformers are situated in the sun, both the absorption of solar heat and the radiation of the transformer heat must be taken into consideration before applying any transformer painting services. The colors that give the best dissipation of transformer heat will allow the highest possible heat absorption from the direct beams of the sun. The coefficients of absorption of solar radiation are as follows:
Light cream paint coating: 0.35
Gray paint coating: 0.75
Aluminum paint coating: 0.55
White lead paint coating: 0.25
Lower co-efficient paint will absorb less heat, and also dissipate heat easily.
There Are No Shortcuts to Reliable Utility Functioning
As you can see and have likely experienced, no utility companies can skimp or cut corners when it comes to providing reliable energy services. Even just a few seconds of a power outage can cause financial and production-related devastation to countless industries.
Power providers need to take a proactive, preventive, and predictive approach to efficiently maintain their transformers and other equipment to ensure a smooth operation at all times. Transformer painting services are a vital part of making sure that your transformers give you the most performance for the longest amount of time. You will not only avoid disruptions in the power grid, but you will also save time and also significant amounts of money. It's a win-win solution.