Norman Lamps, Inc.

Double-ended halogen bulbs have electrical connections at both ends of a linear tubular envelope, creating a compact, high-output light source ideal for work lights, floor lamps, torchiere fixtures, security lighting, and commercial/theatrical applications. The linear form factor allows for efficient reflector designs that direct most of the light output in a useful direction, making these bulbs popular in applications where concentrated light is needed from a relatively compact fixture.

The most commonly encountered double-ended halogens are the J-type (tubular) bulbs used in halogen torchiere floor lamps and work lights. These typically range from 100W to 500W, with 300W being particularly common in residential torchieres. The tubular bulb sits horizontally in a socket with spring-loaded contacts at each end, and a reflector above directs light upward (in torchieres) or outward (in work lights). The concentrated light output makes these bulbs effective, but the high wattages also generate substantial heat.

Length and wattage are the primary specifications you need when ordering replacement double-ended halogens. Common lengths include 78mm (approximately 3 inches), 118mm (approximately 4.6 inches), and 189mm (approximately 7.4 inches), with various wattage options available at each length. The length must match your fixture exactly since the spring contacts are positioned for specific bulb lengths. Using the wrong length means the bulb won't make proper electrical contact or, worse, won't fit at all.

Operating temperatures in double-ended halogens can be extreme due to the high wattages concentrated in relatively small envelopes. Surface temperatures during operation can easily exceed 500-600°F, hot enough to ignite paper, fabrics, or other combustibles placed too close. The high wattages also make the surrounding fixture quite hot. This is why torchiere lamps require wire guards over the bulb to prevent materials from falling onto the hot bulb, and why these fixtures should never be placed under low ceilings or near curtains.

The high energy consumption of double-ended halogens has made them targets for energy efficiency regulations and customer criticism. A 300W torchiere running for just a few hours daily can cost $30-50 annually to operate, and in summer months, the heat output can work against air conditioning. Many customers have sought alternatives, leading to the popularity of LED torchieres and LED replacement bulbs for existing halogen torchiere fixtures. LED alternatives typically use 30-50W to produce equivalent light output, dramatically reducing both energy costs and heat generation.

In theatrical and commercial lighting applications, double-ended halogens serve more specialized roles. T3 quartz halogen bulbs in various wattages provide high-quality, intense light for photography, film production, stage lighting, and architectural applications where excellent color rendering and controllable light are essential. These professional applications often still prefer halogen over LED for the superior color rendering and natural dimming behavior that halogen provides.

Installation precautions are particularly important with double-ended halogens. Never touch the bulb glass with bare hands – oils from skin create hot spots that can cause premature failure. If you do touch the glass, clean it with alcohol before use. Ensure the bulb is fully seated in both contacts before turning on power. Allow adequate cool-down time before attempting to remove a bulb – these bulbs retain heat for several minutes after being switched off. Use the protective sleeve that often comes with replacement bulbs to handle them during installation.

Common Sizes: 78mm (3"), 118mm (4.6"), 189mm (7.4") lengths. Typical wattages: 100W, 150W, 200W, 250W, 300W, 500W

Typical Applications: Halogen torchiere floor lamps, portable work lights, security lighting, under-cabinet lighting, stage and theatrical lighting, photography and film lighting, architectural and display lighting

Key Considerations: Length must match fixture exactly, very high operating temperatures, significant energy consumption, should not touch bulb glass with bare hands, adequate clearance from combustibles required