About Pantograph Isolator – Construction, Characteristics, and Applications | New Topic [2024]

In this note, we are going to know About Pantograph Isolator. Also about its Construction, Characteristics, and Applications as well. Welcome to Poly Notes Hub, a leading destination for Polytechnic Notes for Diploma Engineering Students.

Author Name: Arun Paul.

What is Pantograph Isolator?

A pantograph type electrical isolator is a switchgear device used in power systems to separate a portion of a circuit for maintenance or repair. It consists of a horizontal bar with insulators installed on both ends, similar to the shape of a train pantograph. These insulators provide both electrical insulation and mechanical support.

The pantograph isolator works by raising or lowering the horizontal bar to establish or break electrical connections. When the bar is raised, it forms a gap between the electrical contacts, thus isolating the circuit. In contrast, raising the bar seals the connections, enabling electricity to pass through the circuit.

Construction of Pantograph Isolator

A pantograph-type electrical isolator is typically made up of several important components, like –

1. Main Frame: The primary frame offers structural support while also housing the isolator’s moving elements. It is often constructed of durable materials such as steel to endure mechanical stress and weather conditions.
2. Horizontal Bar: The horizontal bar, which resembles a pantograph arm, is a key component of the isolator. It connects to the main frame and carries insulators at both ends. The bar can be lifted or lowered to open and seal the electrical contacts.
3. Insulators: In order to create electrical isolation between the contacts and the frame, insulators are installed at both ends of the horizontal bar. In order to prevent electrical arcing, these insulators are usually built of materials with a high dielectric strength, such as composite polymers or porcelain.
4. Contacts: Electrical contacts are located at the ends of the horizontal bar and are used to establish or terminate electrical connections. These contacts are often made of copper or other conductive materials that can withstand large current loads with minimal resistance.
5. Operating Mechanism: The isolator has an operational mechanism that can be controlled manually or remotely to raise and lower the horizontal bar. Depending on the isolator’s size and application, this mechanism may consist of gears, levers, or motorized devices.

Characteristics of Pantograph Isolator

Below, we listed some important characteristics of Pantograph Isolator –

1. Electrical isolation capability.
2. Strong mechanical structure.
3. High dielectric strength of insulators.
4. The incorporation of safety elements such as grounding systems.
5. Versatility across multiple applications.

Applications of Pantograph Isolator

Used in Substations, Electrical Distribution Networks, Transmission Lines, Railways Electrification systems etc.