The PFRS-25 compares a transformer’s frequency response to previous results to verify its mechanical integrity. The PFRS-25 instrument is compliant with applicable international IEC and IEEE standards and guidelines (IEC 60076-18 and IEEE C57.149.2012).

Each transformer has a unique frequency response & changes in transformer mechanical geometry can modify it. Movement or transit can cause these alterations. If the transformer has excessive current due to internal or external fault , the physical shape can vary. Power transformer issues can be detected by fingerprinting the transformer’s frequency response:

• Core movements  
• Shorted turns or open windings
• Winding deformations
• Winding connection problems
• Broken clamping structures