Preventing Transformer Disasters: The Crucial Role of Maintaining Oil Levels

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Transformer oil plays a crucial role in the operation and safety of electrical transformers. It acts as both an insulator and a coolant, preventing overheating and ensuring efficient performance. However, maintaining proper transformer oil levels is essential to avoid the risk of fire or explosion. In this blog post, we will explore the significance of testing and measuring transformer oil levels, particularly through ultrasonic testing, and how Coltraco Ultrasonics’ Portatank® can assist in this critical task. 

Testing and Measuring Contents in Transformers:

Regular testing and measuring of transformer oil levels are vital to ensure the transformer operates within safe parameters. Insufficient oil levels can lead to excessive heat buildup, which can cause insulation failure and, in severe cases, fires or explosions. Conversely, overfilling the transformer can result in oil leakage and damage to the surrounding environment. Therefore, it is crucial to maintain the oil levels at the recommended range. 

in pic: An oil transformer at a power generation facility

in pic: Multiple switchgear boards at an industrial facility.

Ultrasonic Testing of Transformers:  

Ultrasonic testing is a non-invasive and highly reliable method for assessing the oil levels in transformers. It allows for the detection of liquid levels through the external side walls of the tank, eliminating the need for drilling or opening the transformer. Coltraco Ultrasonics’ Portatank® is a portable and handheld ultrasonic tank liquid level indicator specifically designed for such applications. 

In pic: The Portatank® main unit is held in hand.

In pic: The Portatank® package features a new oscilloscope

Key Benefits of PORTATANK® for Transformer Oil Level Testing: 

The Portatank®® offers a range of benefits when it comes to testing transformer oil levels. 

  • Non-invasive: Portatank® offers a non-invasive solution for testing transformer oil levels, eliminating the need for drilling or opening the transformer. 
  • Zero downtime: The testing process with Portatank® does not require any system shutdown, ensuring uninterrupted operation and preventing productivity losses. 
  • Versatility: Portatank® can be used on tanks of various sizes, ranging from small 0.5m tanks to large industrial tanks up to 15m in diameter. 
  • Accurate measurements: With an accuracy of +/- 10mm, Portatank® provides highly precise oil level measurements, surpassing conventional sight glass or float level gauges. 
  • Easy operation: The portable and handheld design of Portatank® allows for easy operation by a single person, reducing the need for additional manpower. 
  • Wide compatibility: Portatank® works effectively with different tank wall materials (metals, plastics, glass, etc.) and varying wall thicknesses from 0.5mm to 20mm. 
  • Broad liquid compatibility: Portatank® can measure the oil levels in transformers regardless of the type of liquid, as long as it is in a liquid state. 
  • Clear indication: The single LED light indication of Portatank® provides a clear YES/NO indication of the liquid level, making it easy to interpret the results. 
  • Portable and durable: Portatank® is a portable and durable device that can be easily carried and operated across multiple tanks on the same site. 
  • Cost-effective: As a handheld instrument, Portatank® eliminates the need for installation costs and requires only standard AA batteries for power, providing a cost-effective solution for oil level testing. 

in pic: The Portatank® in action at a Power Generation Facility.

Case Study: PORTATANK® – Accurate Measurement of Oil Levels 

In a recent demo conducted, Coltraco Ultrasonics’ Portatank® was put to the test to measure the liquid levels in various transformers. The demo showcased the effectiveness and accuracy of the Portatank® in identifying the oil levels. 

Two Yorkshire switchgear distribution boxes were tested, and the correct oil levels were successfully identified. Additionally, a larger transformer was also tested using the Portatank®. The identified oil level using the device was found to be three inches below the transformer level shown by the float gauge. To validate the accuracy, the customer manually measured the oil level using a stick and found it to be exactly the same as the level identified by the Portatank®

Based on the successful identification of oil levels in different transformers, it can be confidently stated that the Portatank® liquid level indicator is the ideal solution for non-invasively measuring levels of water and clean liquids in large industrial transformers. 

Click here to read the complete case study

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Maintaining proper transformer oil levels is paramount to mitigate the risk of fire or explosion. Ultrasonic testing, facilitated by Coltraco Ultrasonics’ Portatank®, offers a non-invasive and accurate method for monitoring oil levels in transformers. By implementing regular testing procedures, operators can ensure the safety and efficiency of transformers while minimizing the potential for catastrophic incidents. The Portatank® provides a reliable solution that enables effective oil level measurement without the need for tank modification or downtime. Investing in advanced technologies like the Portatank® demonstrates a commitment to safety and proactive maintenance in critical infrastructure systems. 

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