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Extensive Transformer Testing

As transformers age, regular testing becomes critical to prevent malfunctions that can lead to costly breakdowns and efficiency losses. At Johnson & Phillips, we offer comprehensive transformer testing nationwide, including insulation resistance, power factor, oil analysis, and turns ratio testing, to detect early faults and extend equipment life. With our in-depth approach and specialised tests, we help ensure reliable power delivery and maximise the lifespan of your transformers wherever your operations are located.

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We perform thorough tests to ensure your transformers are operating at their maximum efficiency.

At Johnson & Phillips, our expert transformer testing safeguards your equipment’s performance and safety. We proactively identify and resolve potential issues like overloading, overheating, and moisture ingress before they escalate into expensive problems. Our comprehensive testing covers all critical components, including windings, coils, tap changers, and short circuits, to ensure your transformer runs smoothly and efficiently.

Key Transformer Testing Areas

We focus on the following critical transformer sectors to ensure full functionality and safety:

  • Bushings & Insulation: Assessing insulation integrity and ensuring bushings are free from damage, which helps prevent electrical failures.
  • CTs & Leads: Evaluating current transformers and leads for proper operation and to avoid power loss or malfunction.
  • Tap Changers: Testing for potential faults in tap changers, which can affect voltage regulation.
  • Windings & Core: Ensuring windings and the core are free from short circuits, mechanical damage, and other faults that affect performance.
  • Oil: Evaluating transformer oil to ensure its insulating and cooling properties are optimal for safe and efficient operation.

Our Detailed Testing Methods

We conduct the following tests to ensure your transformer is operating at peak efficiency:

  • Winding Resistance Test: Measures the resistance of transformer windings to detect short circuits and other faults.
  • Dynamic Winding Resistance Test (Tap Changer): Evaluates tap changer resistance to ensure reliable voltage adjustment.
  • Magnetising Current Test: Determines the efficiency of the transformer’s core and detects any excess magnetising current.
  • Short Circuit Impedance Test: Helps evaluate core losses and overall transformer efficiency under load conditions.
  • Transformer Ratios Test: Verifies the primary and secondary winding ratios to ensure proper voltage regulation and transformer operation.
  • Transformer Oil Tests: Measures the dielectric strength and identify contaminants, ensuring the oil performs as needed for optimal transformer operation.

Post-Diagnosis & Repair Services

At Johnson & Phillips, we don’t just identify faults – we offer comprehensive transformer repair and maintenance services to restore your transformer’s full functionality. After diagnosing any issues, we replace essential components like bushings, surge arresters, gaskets, pumps, and fans, ensuring your transformer performs at its best. Our proactive approach extends to maintaining auxiliary parts, guaranteeing long-term reliability and preventing future disruptions. With us, you can trust that your transformer is in expert hands, maximising efficiency and minimising downtime.

Transformer Oil Testing: Ensuring Optimal Performance

Transformer oil plays a critical role in insulating and cooling your transformer. However, over time, its properties can degrade, impacting the performance and safety of the equipment. Therefore, regular oil testing helps ensure that the oil remains effective and meets industry standards.

At Johnson & Phillips, we use advanced on-site testing equipment to measure the oil’s performance. Our testing process applies increasing voltage to the oil until a breakdown point is detected, helping us identify potential issues before they escalate.

Comprehensive Transformer Oil Sampling

Our oil testing begins with a thorough sampling process. This involves collecting multiple oil samples from the transformer to analyse both physical and chemical properties. These tests allow us to detect:

  • Moisture Content: Excess moisture can lead to short circuits and corrosion.
  • Power Factor: Indicates the condition of the transformer’s insulation.
  • Dielectric Breakdown: Measures the oil’s ability to resist electrical breakdown.
  • Acid Number: High acid levels can damage internal components, leading to transformer failure.
  • Flash Point & Viscosity: These help determine the oil’s ability to withstand extreme conditions.

Transformers operate under significant electrical and thermal stress, which can cause the oil to break down over time, affecting insulation and cooling performance. Therefore, routine oil testing allows for early detection of issues like moisture, contaminants, and breakdowns, preventing potential failures.

Maximise Transformer Lifespan & Performance

Ensuring the efficiency and longevity of your transformers is critical to avoiding costly repairs and downtime. At Johnson & Phillips, we don’t just test – we provide actionable insights that help maintain your transformers at peak performance. As a leading transformer manufacturer, we offer a full range of services, from manufacturing to expert testing and repair, giving you confidence that your transformers will perform reliably for years to come.

Get in touch with us today for comprehensive transformer testing and solutions that ensure your operations run smoothly and efficiently.

Electric Transformer Testing
Testing Transformers
Frequently asked questions

Q&A About Our Transformer Testing

Transformers should undergo regular testing to ensure optimal performance and longevity. The frequency of testing depends on the transformer’s age, usage, and operating environment, but it is generally recommended to conduct annual tests and condition monitoring to detect issues early.

Common methods we use at Johnson & Phillips for transformer testing include:

  1. Insulation Resistance Testing: Measures insulation’s electrical resistance.
  2. Dielectric Breakdown Voltage Testing: Assesses insulating oil’s quality.
  3. Power Factor Testing: Evaluates the insulation’s condition.
  4. Dissolved Gas Analysis (DGA): Detects gas levels in insulating oil.
  5. Thermal Imaging: Identifies hot spots and potential issues.
  6. Turns Ratio Testing: Verifies the ratio of primary to secondary windings.

During transformer testing, the following parameters are typically evaluated:

  1. Insulation resistance
  2. Dielectric breakdown voltage of insulating oil
  3. Power factor
  4. Dissolved gas levels in oil
  5. Thermal conditions
  6. Turns ratio
  7. Winding resistance
  8. Load and no-load losses
  9. Voltage regulation
  10. Short circuit impedance

Not conducting regular transformer testing can lead to undetected faults, reduced efficiency, overheating, insulation failure, and, ultimately, transformer breakdown. This can result in costly repairs, unplanned outages, safety hazards, and shorter transformer lifespan.

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