Preventive Maintenance of Medium Voltage (MV) Switchgear

Ensuring Reliability, Safety, and Asset Longevity

Preventive Maintenance MV Switchgear

Medium Voltage (MV) switchgear plays a critical role in electrical power distribution systems, protecting equipment and ensuring continuity of supply. Failures in MV switchgear can lead to unplanned outages, safety hazards, and significant financial losses.
Preventive Maintenance (PM) is a proactive approach designed to detect potential issues early, maintain optimal performance, and extend the operational life of MV switchgear. At PT Multi Daya Mitra, we provide professional preventive maintenance services aligned with international standards and industry best practices.

Why Preventive Maintenance Is Essential

Preventive maintenance is not just a routine activity—it is a strategic investment in system reliability and safety. The key benefits include:

  • Improved system reliability by reducing unexpected failures

  • Enhanced safety for personnel and assets

  • Extended equipment lifespan through early detection of degradation

  • Optimized operational costs by preventing major corrective repairs

  • Compliance with standards such as IEC, IEEE, FM Global and local regulations

Scope of Preventive Maintenance for MV Switchgear

A comprehensive preventive maintenance program typically covers the following activities:

1. Visual and Mechanical Inspection

  • Checking panel enclosures for corrosion, dust, moisture, or physical damage

  • Verifying mechanical integrity of circuit breakers, disconnectors, and interlocks

  • Ensuring nameplates, labels, and safety signage are intact and readable

2. Electrical Inspection and Testing

  • Insulation Resistance (IR) measurement on busbars, cables, and control wiring

  • Contact resistance measurement on circuit breaker main contacts

  • Functional testing of protection relays and tripping circuits

  • Verification of CT and VT secondary wiring conditions

3. Circuit Breaker Maintenance

  • Inspection of operating mechanisms (spring, motor, hydraulic, or pneumatic)

  • Lubrication of moving parts according to manufacturer recommendations

  • Timing and travel tests to confirm proper opening and closing performance

4. Cleaning and Tightening

  • Cleaning of insulation surfaces to prevent tracking and flashover

  • Torque checking of power and grounding connections

  • Removal of dust and contaminants using approved methods

5. Control, Protection, and Auxiliary Systems

 

  • Checking DC supply systems (battery, charger, wiring)

  • Verification of alarms, indications, and interlocks

  • Testing communication interfaces where applicable (SCADA/monitoring systems)

Preventive Maintenance Frequency

The maintenance interval depends on operating conditions, environment, and criticality of the installation:

  • Routine inspection: every 6–12 months

  • Comprehensive preventive maintenance: every 1–3 years

  • Post-fault or abnormal condition inspection: immediately after an event

Sites with high humidity, dust, or continuous operation may require more frequent maintenance.

Our Approach at PT Multi Daya Mitra

We apply a structured and documented preventive maintenance methodology that includes:

  • Experienced and certified electrical engineers and technicians

  • Use of calibrated testing instruments

  • Detailed inspection checklists and test records

  • Clear reporting with findings, risk assessment, and recommendations

  • Maintenance activities performed with strict safety and lock-out/tag-out procedures

  • Preventive maintenance of MV switchgear is essential to ensure safe, reliable, and efficient power distribution. A well-executed PM program minimizes downtime, protects critical assets, and supports long-term operational sustainability.
    PT Multi Daya Mitra is committed to delivering high-quality preventive maintenance services tailored to your operational needs, helping you maintain electrical systems you can rely on.