The DRL lamp, which remains popular, is a representative of gas-discharge lighting devices, characterized by a saturated luminous flux and durability. Mercury-containing products have proven themselves in the arrangement of artificial street lighting and industrial facilities.
However, a number of technical and operational nuances do not allow them to be used in everyday life and cast doubt on their advisability in other areas of life. You will learn all about gas-discharge high-pressure lighting devices from our article. Our tips will help you choose the right devices.
Mercury lamp device
DRL lamps belong to high-pressure gas discharge devices. The priority area of use is lighting of streets, enterprises, garages and industrial workshops. DRLs are used where a powerful luminous flux is needed, and special requirements are not imposed on the quality of color reproduction.
The main functional parts:
- Flask. The outer shell of the device is made of heat-resistant glass. Inside is a quartz burner, to which conductors are connected. Docking of electrodes with cathodes occurs due to the connection of opposite polarities with a carbon resistor. Air is pumped out of the flask, and nitrogen is pumped, the inner surface is covered with a phosphor.
- Basement It is responsible for receiving electricity from the network by connecting the point and threaded contact with the cartridge mounted in the lamp.
- Quartz burner. The main functional element of a mercury lamp. Structurally, it is a quartz flask in which electrodes are placed on both sides: two main and two additional ignition electrodes.
The space of the flask under pressure is filled with an inert gas, providing insulation of the heat exchange between the internal environment and the burner. Additionally, literally a drop of mercury is added there. In the cold state, the mercury compound looks like a plaque on a flask or has the shape of a ball.
To understand the principle of operation of a mercury-arc light bulb, you should familiarize yourself with its structure and the role of constituent elements
Principle of work: the essence of transients
The action of an arc mercury lamp is based on the processes of electric discharge in a gaseous medium, flowing in a bulb under high pressure. This generates a glow source in the form of a spiral in an incandescent bulb. But it is not a hot tungsten filament, but a cord of luminous mercury vapor, “stretched” between the electrodes.
The persistent glow of the DRL lamp begins 8-10 minutes after energizing. During this time, the current flowing in the lighting device is higher than the nominal value, and is limited by the resistance of ballasts.
The duration of the start-up depends on the temperature of the environment - the colder, the longer the lamp “warms up”. After switching on, mercury slowly evaporates during heating and gradually increases the discharge between the working electrodes.
When the mercury component completely passes into a gaseous form, and the pressure inside increases, the bulb will reach its maximum light output.
Electricity is supplied to the lamp, a glow discharge is created between the main and the ignition electrode. As charge carriers accumulate, a breakdown appears between two opposite main electrodes - arc radiation occurs
The voltaic arc in mercury vapor creates a glow of unacceptable color rendition of predominantly blue-green hues. The phosphor is responsible for converting UV radiation into red tones of light. The combination of colors gives a white cold glow of a DRL bulb.
Application specifics: pros and cons of lamps
DRL type illuminators are mainly installed on poles to illuminate streets, roads, parks, adjoining territories and non-residential buildings. This is due to the technical and operational features of the lamps.
The main advantage of mercury-arc devices is high power, which provides high-quality lighting of spacious areas and large facilities.
It is worth noting that the passport data of the DRL on the luminous flux are relevant for new lamps. After a quarter, the brightness deteriorates by 15%, after a year - by 30%
Additional advantages include:
- Durability. The average working life claimed by manufacturers is 12 thousand hours. At the same time, the more powerful the lamp, the longer it will last.
- Work at low temperatures. This is a decisive parameter when choosing a street lighting fixture. Gas discharge lamps are frost-resistant and retain their performance at sub-zero temperatures.
- Good brightness and angle of illumination. The light output of DRL devices, depending on their power, ranges from 45-60 Lm / V. Thanks to the operation of the quartz burner and the phosphor coating of the bulb, a uniform light distribution with a wide scattering angle is achieved.
- Compactness. The lamps are relatively small, the product length at 125 W is about 18 cm, the device at 145 W is 41 cm. The diameter is 76 and 167 mm, respectively.
One of the features of using DRL illuminators is the need to connect to the network through a choke. The role of an intermediary is to limit the current supplying the light bulb. If you connect a lighting device bypassing the inductor, it will burn out due to the large electric current.
Schematically, the connection is represented by the serial connection of a mercury phosphor lamp through a reactor to a power supply. In many modern DRL illuminators, a ballast is already integrated - such models are more expensive than conventional lamps
A number of disadvantages limits the use of DRL-lamps in everyday life.
Significant disadvantages:
- Duration of ignition. Exit to full illumination - up to 15 minutes. It takes time to heat up the mercury, which is very inconvenient in the home.
- Sensitivity to power quality. If the voltage is reduced by 20% or more of the nominal value, the mercury lamp will not turn on, and the luminous device will go out. When the indicator decreases by 10-15%, the brightness of the light deteriorates by 25-30%.
- Noise at work. The DRL lamp makes a buzzing sound, not noticeable on the street, but noticeable in the room.
- Ripple. Despite the use of a stabilizer, the lamps flicker - it is undesirable to perform long-term work in such lighting.
- Low color rendering. The parameter characterizes the reality of the perception of surrounding colors. The recommended color rendering index for residential premises is at least 80, optimally 90-97. In DRL lamps, the value of the indicator does not reach 50. Under such lighting, it is not possible to clearly distinguish between shades and colors.
- Insecure use. In the process, ozone is released, therefore, when operating the lamp indoors, the organization of a high-quality ventilation system is required.
In addition, the presence of mercury in a flask in itself is a potential hazard. Such bulbs cannot be simply thrown away after use. In order not to pollute the environment, they are disposed of appropriately.
Another limitation of the use of gas discharge lamps in everyday life is the need to install them at a considerable height. Models with a power of 125 W - suspension in 4 m, 250 W - 6 m, 400 W and more powerful - 8 m
A significant minus of the DRL of illuminators is the inability to re-enable until the lamp is completely cooled. When the device is operating, the gas pressure inside the glass bulb rises significantly (up to 100 kPa). Until the lamp cools down, it is impossible to break through the spark gap with a starting voltage. Re-activation occurs after about a quarter of an hour.
Selection Criteria: Evaluation of Technical Indicators
When determining the best option for a lighting device, the following characteristics should be taken into account:
- power;
- cap shape / size;
- brightness of a light stream;
- duration of work.
Power. When choosing this option, you should focus on the purpose and location of the lamp. If the device is bought to illuminate the road, then it is necessary to take into account the distance between the lamps - the larger it is, the more productive the lamps should be.
The range of power characteristics of DRL illuminators is in the range of 80-1000 watts. This value is displayed in the labeling of the lamps, for example, DRL 250, DRL 400, etc.
Light flow. The main indicator of light radiation directed in different directions. The parameter is measured in lumens (Lm). It is by this criterion, and not by power, that it is necessary to compare the performance of different types of lamps.
Luminaires with a DRL lamp to produce the desired luminous flux consume more electricity than their LED counterparts and DNaT illuminators. The brightness of the LED device at 100 W corresponds to the illumination index of a mercury-arc counterpart of 400 W
Significant energy savings - a powerful argument in favor of LEDs. The high cost of LED-lamps pays off in the first year of operation.
Basement DRL illuminators are available with the two most popular types of socles:
- E27 - screw form, diameter - 27 mm. Such a base is equipped with mercury-arc devices of 80 W and 125 W.
- E40 - the largest size of the category "E". A 40 mm base is used in lamps of 250 W and above, designed to illuminate spacious areas.
In addition to the type of twisting into the cartridge, the dimensions of the lampshade should also be taken into account.
The width and length of the discharge lamp depends on the power of the device. The higher the performance of the DRL illuminator, the larger and heavier
Service life. This parameter is largely determined by the quality of manufacturing, namely the responsibility of the manufacturer. It is better to choose lamps with a maximum service life. As a rule, high-power devices have a longer life.
For clarity, the general characteristics of lamps of different capacities are given in the summary table. All electrical appliances operate on alternating current, the standard frequency is 50 Hz
Part of the information about the characteristics of the lamps is in the marking. In domestic practice, the letter abbreviation denotes the name of the illuminator, digital - power. The production of mercury lamps is regulated by GOST 27682-88 and GOST 53074-2008.
Foreign products of the DRL type according to the international ILCOS system are labeled QE. Some manufacturers adhere to the pan-European ZVEI and German LBS naming conventions.
Markers of mercury lamps of popular companies:
- HPL - Philips;
- HRL - Radium;
- MBF - General Electric;
- HQL - Osram;
- HSL and HSB - Sylvania.
Additional designations according to ILCOS: QB - models with integrated ballast, QG - spherical bulb, QR - lamps with a reflective inner layer.
Which manufacturer should I prefer?
It is recommended to choose products of well-known brands, it is better to refrain from buying cheap "nameless" Chinese bulbs.
The following manufacturers of mercury devices won confidence among buyers:
- Osram (Germany);
- Philips (Netherlands);
- General Electric (USA / Hungary);
- Next (Poland);
- Eurosvet (Ukraine);
- Lisma (Russia);
- DeLux (China).
In the European market, two brands are considered the leaders in the production and sale of lighting products: Osram and Philips. Both companies have many years of experience - over a century, a wide range and a developed sales network.
The operating parameters of the DRL lamps of leading manufacturers correspond to the declared characteristics, the devices have high efficiency - with a power of 250 W the light flux reaches 12 500 Lm. Estimated cost - 8-10 cu
The factories of the American company General Electric are also located in Europe. The quality of the goods and the service life are not inferior to previous brands, and the price is slightly lower. For a DRL illuminator with a power of 250 W, you need to pay about 7 cu
E.Next is an electrotechnical holding, where the main manufacturer of devices is the group of Polish companies Tarel. The product line features numerous series of different lamps for home, street and industrial lighting.
Compared to German and Dutch lamps of similar power, E.Next 250W illuminators are inferior to competitors in color rendering (Ra = 40) and durability (12000 hours). Estimated price - 5 cu
Mercury-arc lamps of Russian, Ukrainian and Chinese branded production are in the same price category, the average cost of products per 250 W is 3 cu The disadvantage of lighting devices is their limited operation - according to the passport data, the bulbs will last 5,000 hours.
Before buying, you need to check the cap on the quality and "accuracy" of the thread - some users note the difficulty of screwing Lism lamps into the cartridge
Comparison of DRL bulbs with analogues
Discharge lamps are often compared with each other and with more advantageous LEDs. The closest DRL analogues are three types of illuminators: DRV, DRI and DNaT. Let's try to identify the features and competitive advantages of different bulbs.
DRV. The mercury-tungsten arc bulb is very similar in design and operation principle to DRL. Structurally, inside the bulb there is a mercury discharge burner and a tungsten spiral. The last element limits the current for the burner, which means that additional ballasts are not needed.
The main differences between mercury-tungsten lamps and DRL:
- spend more electricity - luminous flux DRV 250 no more than 5500 Lm;
- Estimated time of work - 3000 hours;
- light up for 1 minute.
DRI. Arc mercury bulbs with emitting additives: indium, sodium, waist halogen, etc. Metal components increase the light output of devices to 75-90 Lm / W.
An additional plus of metal halide mercury lamps is an improved color rendering rate. For the operation of DRI, like DRL, they need to be connected via a throttle
DNT. Sodium arc lamps boast maximum luminous efficiency and a long operating period among discharge illuminators. The performance of sodium bulbs over time is not reduced as noticeably as DRL lamps.
Characteristics of DNaT:
- maximum light output - 125 Lm / W;
- working capacity - within 20 thousand hours;
- relative stability of parameters;
- wide range of operating temperatures;
- reaching maximum illumination in 5-7 minutes.
Cons of sodium light sources: significant ripple and low color rendering coefficient, Ra = 25. The radiation spectrum is dominated by red and yellow colors.
Discharge lamps confidently give way to LED options. LED devices surpass their predecessors in all technical and operational parameters.
Indisputable advantages of LEDs: environmental friendliness, minimal ripple, durability, instant inclusion, excellent color reproduction and contrast. In addition to excellent performance, diode devices have temperature and mechanical resistance.
The efficiency of LED lamps is unrivaled, the efficiency reaches 95-98%. The main factor that somewhat restrains the re-equipment of luminaires is the high price of LED lamps
Mercury disposal requirements
Thoughtlessly throw away spent or defective mercury-containing bulbs is not allowed. Devices with a damaged bulb are a serious threat to human health and the environment as a whole, therefore they need specific disposal.
The issue of the procedure for the disposal of unsafe waste is relevant for both business owners and ordinary residents. The processing of mercury lamps is carried out by organizations that have received the appropriate license.
The company enters into a service agreement with such a company.Upon request, a representative of the disposal company visits the facility, collects and removes lamps for subsequent disinfection and processing. Estimated cost of the service - 0.5 cu for one lighting device.
To collect mercury-containing light bulbs from the population, reception points are organized. People living in small towns can recycle hazardous waste through an eco-mobile
If the emission of mercury-containing lamps by enterprises is somehow controlled by the supervisory authorities, then compliance with the disposal rules by the population is the personal responsibility of citizens.
Unfortunately, due to low awareness, not every user of mercury lamps is aware of the possible consequences of mercury vapor entering the surrounding atmosphere.
All types of energy-saving lamps are described in detail in the next article, which discusses the principles of operation, a comparison of devices, a simplified economic assessment.
In the proposed video review, the design of the DRL illuminator is described, the principle of operation is described in detail, and the main nuances of operation are noted:
DRL type discharge lamps are still used in street lighting. The main argument in favor of mercury devices is a powerful luminous flux and affordable cost. However, they are gradually replaced by more advanced lamps, which along with high efficiency can boast of good quality of luminescence and safety of use.
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