Identifying Indicator Lamp Bases and LED Replacements

ABOUT INDICATOR LAMPS

Indicator Lamps are used in industrial equipment, maintenance displays, assembly lines, and other production-type installations. These lights may show when a process is happening, malfunctioning or complete and “indicate” the activity on a control panel. Indicator lamps are also found in toys, appliances, elevators, dashboards, phone systems and audio-visual displays. Indicator bulbs are offered with different bases to accommodate installation in tight spaces and for speciality applications.

TYPES OF BASES FOR INDICATOR LAMPS

Indicator lamp bases vary by size and form. To identify the style of the base, take a look at the interface at the bottom of the bulb. Common styles include:

• Wedge Base
• Midget Flange
• Midget Groove
• Bayonet Base
• Telephone Slide Base
• G-4 Base

In some instances the differences are subtle. Take a look at this comparison between Midget Groove and Midget Flange base lamps

The Midget Flange base has a bottom lip which protrudes beyond the cylindrical shaft of the lamp. A Midget Groove base has an indentation ring just before the bottom of the lamp.

A Bayonet Base (also known as a BA9s base) has a similar cylindrical shape but includes two notches at the base of the lamp.

A Telephone Slide base lamp takes its name from frequent use in telephone switchboards.

Indicator lamps with G-4 Bases have two pins at the bottom that slide into the socket.

Another factor in finding the right match for your indicator bulb is size. Wedge Base indicator lamps are frequently used in 4.5mm (T-1 3/4) and 10mm (T-3 1/4) sizes.

LED REPLACEMENTS FOR INCANDESCENT INDICATOR BULBS

LEDs have been created to retrofit incandescent indicator lamps. LEDs are more energy efficient, run less hot and are longer lasting than traditional filament bulbs. To retrofit your indicator, check the voltage of your application and identify the base needed.

LED Indicator bulbs work well in new applications for industries including automotive, gaming, marine and avionics. Their based design allows for swap ability with colours or brightnesses.

RS offers a range of JKL Components LED Indicator bulbs including:

• Wedge Base LEDs - Voltages: 12V, 24V, Sizes: T-1¾ (4.5mm), T-3¼ (10mm)
  Multiple colours, Flat Wedge shapes Available
• Midget Flange Base LEDS -Voltages: 24V, Size: 6mm diameter
• Midget Groove Base LEDs - Voltages: 24V, Size: 6.2mm diameter
• Bayonet Base LEDs -Voltages: 6V, 24V, Size: BA9S
• Telephone Slide Base - Voltages: 36V, Size: T5.5
• G-4 Base - Voltages: 12V, 24V, Sizes: 13mm diameter cylinder, 23mm flat disc