A medium voltage disconnect switch (MV disconnect switch), also referred to as an isolating switch or isolator, is an essential component in electrical systems operating between approximately 1kV and 35kV. GEE provides indoor medium voltage disconnect switches with standard rated voltages of 12kV, 24kV, and 40.5kV, specifically designed for use in medium voltage switchgear cabinets.

The primary purpose of an MV disconnect switch is to provide a visible and reliable isolation point, allowing safe separation of equipment from live circuits during maintenance, inspection, or repair. Unlike circuit breakers or load break switches, these switches do not interrupt current under load and are intended to be operated only after another protective device has already interrupted the circuit, ensuring safe and complete isolation within the switchgear.

Key Functions and Benefits

Indoor medium voltage disconnect switches are critical for both safety and operational efficiency in electrical installations. By physically isolating sections of a switchgear circuit, they prevent accidental energization and protect maintenance personnel from electrical hazards. At the same time, these switches enhance operational flexibility by allowing certain parts of the system to remain in service while maintenance is performed on isolated sections, minimizing downtime and maintaining reliable operation of the overall electrical network.

Disconnect Switch vs. Circuit Breaker

While both disconnect switches and circuit breakers are used to control electrical circuits, their functions differ fundamentally. A medium voltage disconnect switch provides a visible point of isolation and operates only after the current has been interrupted, without the capability to break load or fault currents. Circuit breakers, on the other hand, are designed to automatically interrupt fault currents, such as overloads and short circuits, protecting equipment and preventing hazardous conditions. Circuit breakers can also be manually switched under normal load, which disconnect switches are not intended to do.

Selecting the Right Indoor MV Disconnect Switch

Choosing the appropriate indoor medium voltage disconnect switch depends primarily on the system voltage, switchgear design, and operational requirements.

• GEE’s 12kV, 24kV, and 40.5kV indoor disconnect switches are specifically engineered for use in enclosed switchgear cabinets, meeting strict safety standards and providing reliable isolation for maintenance and inspection tasks.

Reviewing the technical specifications is essential to ensure the selected switch meets your installation’s voltage rating and operational needs. For further guidance, GEE’s experienced team can provide professional recommendations to help select the most suitable indoor MV disconnect switch for your switchgear application.