Partial or absent maintenance history

The failure or partial recording of maintenance activities on a power transformer represents a critical issue that can compromise the safety and reliability of the electrical system. The absence of a complete historical record prevents reconstructing the transformer’s health status over time, hindering early fault diagnosis and the implementation of targeted maintenance interventions.

• Historical maintenance record – The systematic collection and archiving of all maintenance activities performed on a transformer.
• Preventive maintenance – Scheduled interventions to prevent faults and maintain transformer efficiency.
• Corrective maintenance – Actions taken to repair unexpected faults or malfunctions.
• Maintenance management system – Software and procedures for documenting and managing maintenance activities.

International standards related to power transformer maintenance emphasize the importance of proper documentation of maintenance activities.
For example, the IEC 60422:2013 standard “Mineral insulating oils for electrical equipment – Guide to maintenance and supervision” states that “maintenance documentation should be kept for the entire service life of the transformer“.
IEC 60076: International standards for the design, manufacture, and testing of transformers.
ISO 55000: Standards for asset management, including electrical transformers.

The main causes of PARTIAL OR ABSENT HISTORICAL MAINTENANCE RECORDS are:
Lack of adequate maintenance procedures
The absence of documented procedures for transformer maintenance can lead to suboptimal management of maintenance activities and the failure to record them.

Poor maintenance culture
A lack of awareness of the importance of preventive maintenance can lead to neglect in recording maintenance activities.

Lack of resources
The lack of qualified personnel or dedicated economic resources for maintenance can limit the ability to adequately document maintenance activities.

Management change
Ownership or management change without proper transfer of historical information.

Data loss
Lost or damaged data due to accidental events or computer system malfunctions (partial backups).

Inadequate IT systems
Use of obsolete or unsuitable IT tools for managing maintenance information.

The signs indicating a potential PARTIAL OR ABSENT HISTORICAL MAINTENANCE RECORD include:

• Lack of documentation: Absence of maintenance logs, invoices, or other documents that certify the maintenance activities performed on the transformer.
• Incomplete or unreliable information: Available maintenance documentation is incomplete, unreliable, or outdated.
• Lack of traceability of interventions: It is not possible to trace the maintenance interventions performed on the transformer in the past, nor to identify the technicians or companies that carried them out.
• Frequency of faults: Increased frequency of faults without a clear identified cause.

Symptoms that may manifest due to PARTIAL OR ABSENT HISTORICAL MAINTENANCE RECORDS include:

• Reduction in transformer reliability
  Increased risk of transformer faults and malfunctions.
• Difficulty in fault diagnosis
  The absence of information on the transformer’s past conditions makes it more difficult to identify the cause of faults.
• Increased maintenance costs
  The need for more invasive and costly maintenance interventions due to lack of prevention.
• Component degradation
  Increased wear and degradation of the transformer’s internal components.

The diagnosis of PARTIAL OR ABSENT HISTORICAL MAINTENANCE RECORDS is based on an assessment of the available maintenance documentation, if any, and an in-depth investigation of the information related to past maintenance activities performed on the transformer.

• Verification of documentation: Review of company procedures for recording maintenance activities.
• Audit of maintenance data: Check and evaluate available historical data to identify gaps and inconsistencies.
• Interviews with staff: Collection of qualitative information through interviews with maintenance personnel.

The prevention of PARTIAL OR ABSENT HISTORICAL MAINTENANCE RECORDS requires the implementation of adequate maintenance procedures, training of maintenance personnel, and allocation of sufficient resources for managing maintenance documentation. We can summarize it as:
Adoption of software and procedures for accurate and continuous recording of maintenance activities.

Educating staff on the importance of accurate and continuous documentation (training).

Conducting periodic audits to ensure the completeness and accuracy of maintenance records.

Implementing real-time monitoring and diagnostic systems to integrate and support maintenance data.

Therapies to remedy PARTIAL OR ABSENT HISTORICAL MAINTENANCE RECORDS include:

• Reconstruction of historical data
  Collection of information on past maintenance activities performed on the transformer, including through interviews with maintenance personnel or consultation of historical archives.
• Implementation of an effective maintenance documentation system
  Development, implementation, or updating of a system for recording and managing maintenance documentation related to the transformer.
• Staff training
  Training maintenance personnel on the importance of documentation.