Low Pressure Mercury Lamp

This article discusses the construction and working principle of low pressure mercury fluorescent lamps also known as tube lights.

Low pressure mercury lamp.

The average life of tube lights is about 5000 hours and also. Right around 1900 the mercury arc rectifier was developed this luminous device was very important for power conversion. Rather than a cold spot the lamp s amalgam spot on pellet regulates mercury vapor pressure during operation and yields up to three times the uvc output of a standard low pressure mercury lamp of the same length. The low pressure uv lamps also called germicidal lamps exploit uvc light to get the rapid sterilization of bacteria molds fungi viruses and microorganisms both in air and in water in this category of lamps about 40 of electricity is converted directly into uvc radiation with monochromatic emission at 254 nm for germicidal applications and at 185 nm for the oxidation of surfaces.

A sodium vapor lamp is a gas discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm. Nyc subways were still using original mercury arc rectifiers to convert ac to dc power up until the end of the 20th century. The low pressure mercury fluorescent lamps are commonly called as tube lights. They differ primarily by electrical excitation and ionization levels of the mercury within the lamp and corresponding internal pressures.

The higher efficiency of the amalgam lamps allows less lamps per system or lower wattage lamps in the system while achieving the same results as standard low pressure mercury lamps. Low pressure mercury lamps have been manufactured in jelight company inc. Low pressure and high pressure low pressure sodium lamps are highly efficient electrical light sources but their yellow light restricts applications to outdoor lighting such as street lamps where they are widely used. Ushio germicidal lamps are low pressure mercury arc lamps that emit radiation peaking at 253 7nm uv c.

These early low pressure lamps used a lot of mercury today s lamps use a tiny amount of mercury. Life time of the amalgam lamps are in excess of 12 000 hours with. Two varieties of such lamps exist. Amalgam lamps use a mercury amalgam mix to control mercury vapor pressure.

If synthetic quartz is used then the transparency of the quartz is increased further and an emission line at 185 nm is observed also. Low pressure mercury vapor lamps usually have a quartz bulb in order to allow the transmission of short wavelength light. Designed by experienced engineers and by using quality material in combination with a tightly controlled manufacturing process we provide high quality lamps free of impurities to maintain strong and stable output throughout life of the lamp. Such a lamp can then be used for ultraviolet germicidal irradiation.

Since 1978 for a variety of applications such as. The power ratings are from 4 watt to 125 watts. Amalgam lamps use less mercury than standard low pressure mercury lamps and are rohs compliant.