Transformer Testing & Maintenance
Power Transformer Failures
The importance of risk assessment and the role of Reliability-based DGA
Transformer Testing & Maintenance
Dielectric Voltage Testing – Standard Methods
There are two standard methods from ASTM International: D877, Standard Test Method for Dielectric Breakdown Voltage of Insulating Liquids Using Disk Electrodes, and D1816, Standard Test Method for Dielectric Breakdown Voltage of Insulating Oils of Petroleum Origin Using VDE Electrodes.
VDE stands for Verband Deutscher Electrotechniker—the Association for Electrical, Electronic, and Information Technologies— a German standards organization similar in function to the Institute of Electrical and Electronics Engineers (IEEE) in the United States. The D1816...
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The importance of risk assessment and the role of Reliability-based DGA
By Chuck Hoeppner, Delta-X Research It’s often said that you can’t manage what you can’t measure. But how does one manage risk in the mission-critical, 24x7 world of energy utilities? It’s a challenging undertaking, anticipating future demands and ensuring the reliability...
Insulation Resistance Test
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Harmonic Problems in Power Transformers
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Dielectric Voltage Testing – Standard Methods
There are two standard methods from ASTM International: D877, Standard Test Method for Dielectric Breakdown Voltage of Insulating Liquids Using Disk Electrodes, and D1816, Standard Test Method for Dielectric Breakdown Voltage of Insulating Oils of Petroleum Origin Using VDE Electrodes. VDE stands...
Case Study: Rapid Changes in Bushing Health
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Hydrogen Monitoring in the Transformer Headspace Compared to Traditional In-Oil Monitoring
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The Distribution Transformer - Critical Power System Component
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Grounding Transformers Explained
By R. W. Hurst, Editor Grounding transformers are used to provide a path to ground for unbalanced load current and for fault currents on systems where a suitable ground is otherwise not available. Grounding transformers are normally constructed with one of the two configurations: Zig-Zag (Zn) with...