Introduction

• When current flows through the tube, electrons hit mercury atoms taking them to excited state
• Energy from these excited atoms is released in the form of Ultra Violet Radiation
• The Ultra Violet rays are converted to visible light by the phosphor coating on the inside of the tube

]]> Components of Fluorescent Lamp Glow Starter
Connected in parallel to the fluorescent lamp

• Consists of a small discharge tube connected in parallel with a normally open switc
• Bimetallic strip used for switching purposes

Ballast
High inductive coil used in series

• Generates a high voltage pulse across the tube during start up
• Limits flow of currentduring normal running time

Electronic ballast provides instant start (no separate starter required) and is more efficient than inductive ballast, but is costlier]]> Run Details of Fluorescent Lamp

• In the circuit for Run 1, fluorescent lamp has inductive ballast, while the circuit for Run 2, the fluorescent lamp has electronic ballast
• The ballast, lamp, ammeter and current coil of the wattmeter is connected in series
• The voltmeter and pressure coil of wattmeter are connected across the device for measuring the voltage
• Variac is used for the step up andvariations of supply voltage required for the experiment

]]>