All About Electrical Isolator: Electrical Isolation Switch

Introduction

What is an electrical isolator?

An isolator is also known by names like Disconnector and Isolation/ Disconnect switch.

An isolator is a mechanical switch which isolates a part from the power source as when required. It may be a part or another portion of the circuit.

Definition:
A manually operated mechanical switch which separates the part from the electrical source of power.

Both the opening and closing action are done when there is no current flow.

Read: Wien's Displacement Law

It ensures a complete de-energization of the circuit for service. It is actuated when there is a no-load condition. It cant be operated, like a circuit breaker, in on-load condition.

• What if I operate an isolation switch when there is a load?

The answer is you will surely lose your switch. It will be damaged badly producing a heavy arc. This can also damage the surrounding parts and circuit.

• Why isolation is required in an electrical circuit?

For safety.

Yes. Isolation of the circuit is done to avoid shock hazards. You don't want to get an electrical shock and that current flow through you when you open panel for any maintenance. An isolator ensures safety.

Isolators can be operated either electrically or manually.

Read: Rockwell Hardness Test: Theory, Experiment, Difference & Advantages

Now, let's get introduced to the different types of Disconector.

Types of Electrical Isolators

• Verticle break type single, double or triple pole isolator
• Horizontal two rotating posts, center break type isolator
• Horizontal break center rotating double break isolator
• Extra high voltage column isolator