The mercury vapor lamp is a high-pressure gas discharge lamp further. The glass bulb of mercury vapor lamps, high pressure usually has an elliptical shape. Inside the bulb is a quartz discharge tube, the mercury vapor. Because there are two main electrodes, is ignited by two ignition electrodes, which are located directly on 230V mains voltage (see figure).
The mercury vapor high-pressure lamp contains a discharge tube made of quartz (burner) that is associated with mercury and argon gas filled. The burner contains an ignition electrode, so that these lamps require a ballast operation only. The ignition takes place directly at the mains voltage of 230 volts.
The output light from mercury vapor lamps is about 3 times as lighter as the incandescent lamp, here is about 30-60 lm / W. The average lifespan is about 6 times greater, it is around 6000 hours. Without phosphorus on the inside of the glass spheres are light bluish-white color. Mercury vapor lamps require 3-5 minutes of heating, process re-ignition is possible only after cooling.
After startup process it barely lit first. Only when a certain quantity of mercury is vaporized and increasing the gas pressure in the burner, it will be brighter. Available in 50, 80, 125, 250, 400 and 700 watts.
Mercury vapor lamps Application
Mercury vapor lamps are used primarily for street lighting or floodlighting of sports fields and stadiums. Also for the illumination of churches, castles or large buildings, they are used.
Mercury vapor lamps Circuit
To limit the current in the circuit requires the lamp ballast. By this measure the power factor cos is reduced to about 0.5.