Electrical transformers keep various industry operations on track. However, like any piece of infrastructure, they don’t last forever. Wear and tear, external factors and mechanical stresses can lead to breakdowns, unexpected failure or replacements.
Businesses can ensure transformer lifespan extension through regular maintenance. Upkeep can reduce downtime, improve safety and prevent transformer failure.
Discover transformer care guidelines below.
1. Conduct Routine Inspections
Routine inspections are vital for optimizing transformer performance. They allow businesses to catch problems before equipment fails. Knowing what to check for during an inspection is as important as conducting one in the first place. Here’s what businesses should focus on:
- Oil leaks
- Corrosion or rust
- Overheating signs
- Document gauge readings for vacuum pressure, liquid level & temperature and coil temperature for dry type transformers.
- Loose or damaged connections
- Unusual noises
The frequency of inspections depends on how critical your transformer is to operations and the environments it operates in. Some parts need to be checked daily, while others require a more thorough review every few months or years. Here’s when to review transformer parts:
- Daily to weekly: Conduct visual checks for leaks, overheating and unusual noises.
- Monthly or quarterly: Businesses should check oil levels and cooling systems. They may also look for signs of corrosion or wear.
- Annually: This is where in-depth testing comes into play, including resistance tests and oil analysis.
2. Perform Regular Tests
Visual inspections are a great first line of defense, but they might not tell the whole story. Electrical and oil-based tests provide deeper insight into a transformer’s health. Major tests that businesses should conduct include the following:
- Insulation resistance test: This helps companies measure how well the transformer’s insulation is holding up. If resistance levels drop, it could point to moisture contamination or insulation wear.
- Turns ratio test: The ratio test ensures the transformer maintains its designed voltage values. A deviation in the turns ratio suggests deterioration or damage to the transformer’s core components.
- Power factor: Also known as dissipation factor, this test assesses the state of the insulation. A rising power factor may suggest the maintenance team needs to change the oil or look for other issues.
3. Analyze the Oil
Transformer oil serves as insulation and prevents electrical arcing between components. It also helps dissipate heat to prevent the transformer from overheating. Regular oil analysis is a vital maintenance step for durability — it allows businesses to identify if heat, moisture or contaminants have deteriorated the fluid. Transformer insulated fluids should be analyzed every twelve (12) months to identify any trends or variations. For larger or more critical units, online or continuous (remote) monitoring may be suggested for real time trends and analysis.
Oil analysis also gives businesses a picture of the condition of the internal components. Here’s what to look for when analyzing transformer oil:
- Moisture content: Water is one of the biggest threats to transformer oil. Even small amounts of moisture reduce insulation strength.
- Dissolved gas analysis (DGA): DGA detects gases like hydrogen, carbon monoxide and acetylene in the oil. Depending on the level, it can signal overheating, arcing or other failures.
- Acid number: A rising acid number — because of the formation of carboxylic acids — means the oil is deteriorating.
- Dielectric strength: This measures the oil’s ability to withstand electrical stress. Low dielectric strength means the fluid is losing its insulating properties.
If tests reveal contamination or degradation, there are a few steps businesses can take:
- Identify the source of the problem: This might involve an internal inspection for damaged or loose connections, a pressure test for any leaks or additional electrical testing.
- Oil filtration: If the oil isn’t severely degraded, filtration can remove contaminants and restore its performance.
- Dehydration: If moisture levels are high, dehydration processes can remove water and improve the oil’s insulation strength.
- Complete oil replacement: If the oil is too deteriorated, it’s best to replace it for safety.
4. Manage Loads
Transformers can handle specific loads, but as business operations expand, power demands typically increase beyond what the system can handle. Without proper load management, transformers can overheat, lose efficiency and fail prematurely.
Businesses may only realize they’re overloading their transformer when issues arise. However, some signs can help catch the problem early:
- Frequent tripping of protective devices like circuit breakers or relays
- The transformer casing feels unusually hot, suggesting that it’s struggling to dissipate excess heat
- Constant voltage drops or fluctuations
- The transformer produces unusual noises
Load testing measures how much power a transformer is handling compared to its designed capacity. Regular assessments help companies decipher if the transformer is being overburdened and make necessary adjustments. To keep a transformer operating efficiently, businesses should implement a proactive load management strategy.
Follow the equipment longevity tips below to manage connected equipment:
- Monitor load levels regularly: Use monitoring equipment to track usage patterns and detect signs of overload.
- Distribute loads evenly: Avoid concentrating a single transformer by balancing loads across multiple units.
- Plan for future growth: If businesses expect power needs to increase, they should upgrade to a higher-capacity transformer or add supplementary power systems.
5. Monitor Cooling Systems
Heat buildup can hasten the aging of insulation materials, weaken electrical components and result in equipment malfunction. Proper cooling ensures the transformer operates within the safe temperature limits.
When trying to decide if a cooling system is functioning as it should, businesses should monitor the following components:
- Cooling fans and pumps
- Radiators and heat exchangers
- Oil circulation system
- Temperature gauges and sensors
Besides monitoring these parts, organizations should routinely maintain them to keep them functioning optimally. Preventive upkeep includes:
- Cleaning cooling fans and radiators to remove dust and debris.
- Checking for leaks in oil circulation systems and ensuring pumps are working correctly.
- Verifying that sensors are working as expected.
If a transformer’s temperature rises beyond safe limits, here are some steps businesses can take:
- Verify fans and fan controller power: Check to make sure fans and controllers have power and can operate in manual mode and upon desired set points.
- Reduce load: Lowering the electrical demand can help stabilize temperature levels.
- Check for obstructions: Blocked air vents, clogged radiators or malfunctioning fans can restrict cooling.
- Consult a professional: If overheating continues despite corrective actions, seek expert maintenance services to diagnose and resolve the issue.
6. Schedule and Record Maintenance
Long-term equipment maintenance requires scheduling and accurate recordkeeping. In-house maintenance teams can handle inspections and basic upkeep, but transformers may require specialized expertise for in-depth assessments. Partnering with a professional maintenance provider ensures:
- Accurate testing and diagnostics.
- Preventive maintenance strategies.
- Emergency repairs and support.
- Regulatory compliance assurance.
Professionals will provide records of inspections, tests and repairs. Having documents of past issues and overhauls makes diagnosing future problems faster and easier. Additionally, when businesses know the condition of their unit, they can decide when to invest in replacements or upgrades.
7. Repair Promptly
Preventing transformer failure involves addressing signs of trouble immediately. For anything apart from routine maintenance, businesses should consult experts for repairs. If a transformer needs to be taken offline, businesses may need a temporary power solution. They can opt for rental or substation transformers to keep operations on track.
If a transformer is beyond repair, manufacturers offer sustainable reconditioning options. After the service, it’s crucial to schedule ongoing upkeep to assess the health of the unit.
Extend the Lifespan of Your Electrical Transformer With Sunbelt Solomon
If you’re looking to keep your transformer in peak condition, Sunbelt Solomon can help. We have over 100 years of experience providing full-service power solutions for businesses in various sectors. Our experts buy, repair and recondition transformers to provide the best option for your needs. We also offer quick-ship inventory, on-site field maintenance and temporary rental solutions to minimize downtime.
Contact us today to prolong the life of your unit.
