HPS lamps: principle of operation, advantages and disadvantages of high and low pressure sodium lamps

Gardeners often use artificial lighting to grow seedlings at home. HPS sodium lamps have excellent properties. They have long been used in greenhouses to increase the yield of vegetables and other crops. In addition to the household sphere, such devices are used in industry and other areas.

general description

HPS lamps have a wide range of applications. The abbreviation of the name stands for "arc sodium tubular". These bulbs are used everywhere. It is possible to choose products with a power from 70 to 400 watts. The basis for the light source is the burning of the arc in the area of ​​different pressure levels, depending on the sodium vapor in the bulbs. Because of this, the devices can be high and low pressure. The latter option is considered to be more economical, efficient and reliable.

The entire cycle of the light bulb takes place in a special outer tube (burner) in the form of a cylinder, made of pure aluminum oxide. The inside of the flask is filled with vapors:

• sodium amalgams (mercury alloy);
• xenon gas.

It is inert xenon and performs the function of ignition. The burner (tube) of the DNaT lamp is placed in a glass bottle with a threaded base. Power indicators can be E-27 or E-40.

Principle of operation

By design, sodium light bulbs are quite simple, so the principle of their operation is not considered complicated. They differ little from the functioning of other types of gas-discharge lamps. They need a pulse ignition device (IZU) and a choke. As soon as the IZU turns on, it starts to supply pulses to a light bulb with a voltage of several kilovolts. As a result, a discharge occurs in the gas-discharge cylindrical tube, and an arc arises. In order to maintain normal operation and stable voltage, an inductor must be included in the operating circuit.

Modern companies have managed to launch the production of HPS lamps of a new design. They do not need an IZU, since they are equipped with electronics (electronic ballasts). It makes it possible to regulate the power consumption of electricity, which extends the life of the light bulb.

During operation, HPS lamps emit golden-white or bright orange light due to sodium vapor. The maximum heating can be up to 300 ^OC, therefore the cartridge in the product is made of ceramic. The required power source is 220 V.

Advantages and disadvantages

Since the day of its invention, the HPS lamp has remained one of the most energy efficient and inexpensive. The higher its power, the better the light output. Such devices have many positive characteristics:

• even with long-term operation, a powerful luminous flux comes in;
• long service life, 2 times exceeding alternative light sources (it is about 20,000 hours);
• small starting and operating currents, providing good energy savings;
• application in regions with any climate;
• even at low temperatures, 100% ignition occurs;
• The efficiency of the product is quite high and amounts to about 30%.

Despite the listed positive characteristics, light bulbs have their drawbacks. One of them is the long period of time required to return to normal operating conditions. It is about 7 minutes long. Another drawback is poor color rendering. Since the light is bright orange in the lamp, all other colors are distorted and not well illuminated. All of these disadvantages lead to limiting the use of the sodium device.

Application area

Sodium light bulbs are widely used in various fields. This is due to the good benefit and efficiency of the light source. They are often used to create outdoor lighting in an area:

• streets with pedestrian crossings;
• squares and parks;
• highways;
• construction sites;
• airports and tunnels.

Thanks to such lamps, the eyes of drivers are less tired in the dark, better visibility is created in bad weather conditions. In fog, lighting fixtures eliminate negative phenomena due to the power of the luminous flux. It creates an increased contrast for all illuminated objects. High pressure sodium lamps good suitable for large rooms, for example, gyms, industrial and retail complexes. Light bulbs emit light that allows better color differentiation over a wider range. The only exceptions are shortwave devices that tend to fade.

Many greenhouses and greenhouses began to use sodium lamps as an additional source of light. To this end, manufacturers have mastered the production of HPS with a special spectrum of light radiation, which benefits plants. Special luminaires perform two important functions at once: they serve as protection against direct penetration of dirt and splashes and provide air supply to cool the light bulb.

Features of HPS

One of the distinguishing features of sodium lamps is their specific acrid yellow color of the radiation. It is monochromatic and has a high ripple factor, which disturbs color reproduction. For this reason, such lamps are not used in residential buildings., as well as in office, industrial and educational premises.

A high level of light output is one of the main quality indicators of light. The ignition characteristic of the lamp makes it unsuitable for use in lighting systems with frequent off and on cycles. Before the next start, the DNaT should "rest" for 3-6 hours.