Galvanometer Construction

Description:

Introduction

Galvanometer is a device used to measure presence of electric current. It is placed in between a current carrying conductor to measure the current flow.

Principle

It works on the principle of torque in a current carrying coil kept in magnetic field.

Diagram and description

Components

• Coil on frame.
• Magnets with cylindrical head.
• Hair spring.
• Indicator and scale.

Assembly

There are two magnets with cylindrical head, one acting as North pole and other as a South pole. A soft iron cylinder is placed between the magnets that is free to rotate on the spindle. A copper coil is wrapped on a frame which is present on the soft iron cylinder. A hair spring is also present at the bottom of the spindle; one end of the spring is attached to the spindle while the other end is attached to the fixed frame so, when the spindle rotates the spring gets tightened up that generates a counter torque. An indicator and a scale is also present to display the amount of torque.