Welcome to MSC, this site is screen reader friendly.

  • Help
    • 1-800-645-7270
    • Live Chat
    • Help Center
    • About Us
  • Cart
Help

24/7 Customer Care

  • 1-800-645-7270
  • Live Chat
  • Help Center
  • About Us

Incandescent Lamps Technical Information

Shop All Lighting
Basics of... Incandescent and Halogen Lamps

Incandescent Operation

In an incandescent lamp, a tungsten filament is heated by an electric current until the filament becomes incandescent or gives off light. The life of a lamp depends on the thickness of the tungsten filament; a thick filament will last longer than a thin one. But a thick filament does not get as hot so it produces less light. That's the trade-off - if you want more life, you get less light and vice-versa.

Incandescent Lamp

Halogen Operation

Halogen lamps are technically incandescent lamps, but they have three features that make them superior to standard incandescents: they are brighter, whiter and last longer. A Halogen lamp has a thin filament. A thin filament produces more light than a thick one. This makes it brighter and whiter. But how does it last longer despite having a thin filament? The Halogen Cycle: in a Halogen lamp the filament is contained within a glass capsule inside the lamp itself. The Halogen gas inside the glass capsule transports the broken down tungsten back to the filament before it has a chance to deposit on the lamp wall, thus replenishing it and keeping the lamp clean and bright. The halogen gas actually regenerates the filament.

Incandescent/Halogen Bulb Shapes

  • Letters designate the shape of the glass lamp
  • Numbers indicate the diameter of the lamp in eighths of an inch
  • For example, "G-40" indicates a globe shaped lamp having a diameter of 40 eighths or 5 inches
Incandescent/Halogen Bulb Shapes

Incandescent/Halogen Bulb Bases

Screw bases are made of Aluminum, Brass or Nickel-Plated Brass. Aluminum is the most economical material. Brass and Nickel-Plated Brass bases are corrosion resistant and are used on lamps designed for outdoor use, very long life or in corrosive environments that might cause a lamp to seize in the socket and make replacement difficult

Incandescent/Halogen Bases
Back to Index