Sodium Vapour Lamp

Sodium Vapour Lamp consists of a discharge tube created from a heat resistant glass, containing a modest quantity of metallic sodium, neon gas and two electrodes, Neon gas is added to start the discharge and to create adequate heat to vaporize the sodium. Because of law pressure inside the tube, a sufficiently extended tube essential to acquire far more light. To minimize the all round dimension of the lamp, this tube is generally bent into U-shape.

The light made by this lamp is yellowish which is produced at vapor4life coupon its optimum pressure of about .004mm of mercury. This pressure is obtained at a temperature of about 280 C and so it becomes necessary to maintain this temperature. For this purpose the U-tube is enclosed in a double walled flask to prevent shed of heat. The double walled wholesale v2 cigs coupon flask is interchangeable and can be fitted on to an additional U-tube. Whilst replacing the inner U-tube one particular must be quite cautious due to the fact if it is broken and sodium comes in make contact with with moisture, it might outcome in fire.

All electric discharge lamps call for a greater voltage at the time of beginning and low voltage for the duration of operation. Normally, sodium vapour lamps are operated by a high leakage reactance transformer. At beginning a high voltage of about 450 volts is applied across the lamp which is enough to start off the discharge. rate us When the lamp is totally operative right after ten - 15 minutes, the voltage across it falls to about 150 volts. Because of the high reactance of circuit, the power factor is low and therefore a p.f improvement capacitor is connected.

The efficiency of a low pressure sodium vapour lamp is extremely high (about 40 - 50 lumens/watt) and it produces a light of distinct wavelength having yellow color. Sodium lamps are mainly employed for street, high way and airfield lighting exactly where color distinction is not so essential.