10kV RMU Common Faults & Solutions Guide

Application Issues and Handling Measures for 10kV Ring Main Units (RMUs)

The 10kV ring main unit (RMU) is a common electrical distribution device in urban power distribution networks, primarily used for medium-voltage power supply and distribution. During actual operation, various issues may arise. Below are common problems and corresponding corrective measures.

I. Electrical Faults

• Internal Short Circuit or Poor Wiring
  A short circuit or loose connection inside the RMU can lead to abnormal operation or even equipment damage.
  Measure: Promptly inspect the internal components, repair any short circuits, and re-terminate connections securely.

• External Short Circuit Faults
  External short circuits may cause the RMU to trip or result in fuse blowouts.
  Measure: Quickly locate and eliminate the fault point, replace blown fuses, or reset/repair the tripped protective device.

• Leakage Current (Ground Fault)
  Insulation failure or leakage current poses electric shock hazards and may lead to fire.
  Measure: Immediately identify and repair the leakage point, reinforce insulation, and ensure safe and reliable operation.

II. Mechanical and Auxiliary Device Issues

• Inflexible Operation of Components
  If mechanical components such as switches or circuit breakers operate stiffly, it may result in improper switching or operational failure.
  Measure: Regularly lubricate and maintain moving parts to ensure smooth, reliable operation.

• Failure of Auxiliary Devices
  Devices such as voltage transformers (VTs) and current transformers (CTs) may fail, leading to inaccurate voltage and current measurements.
  Measure: Timely replace faulty transformers to ensure measurement accuracy and system monitoring reliability.

III. Environmental Issues

• Excessive Temperature
  High operating temperatures can cause equipment damage or overload.
  Measure: Improve ventilation, maintain a suitable ambient temperature, and reduce load when necessary to prevent overheating.

• Humid Environment
  Operating in damp conditions may degrade insulation performance, increasing the risk of leakage and safety hazards.
  Measure: Keep the surrounding area dry and enhance moisture-proof insulation measures (e.g., use of desiccants, sealed enclosures, or heating elements).

Conclusion

To ensure safe and reliable operation of 10kV ring main units, regular maintenance and inspections are essential to detect and address potential faults early. Additionally, operators must be well-trained with strong technical skills and safety awareness, strictly following operational procedures to prevent human errors. Only through comprehensive management and proactive maintenance can the reliability and stability of urban power supply be guaranteed.