DRL lamps: device, characteristics, selection rules
DRL electric lamp is a representative of gas-discharge lighting devices, characterized by a saturated luminous flux and durability. Mercury lamps have proven themselves in the arrangement of artificial lighting of streets and industrial facilities.
However, a number of technical and operational nuances do not allow them to be used in everyday life and call into question their expediency of use in other areas of life.
Mercury lamp device
DRL lamps refer to high-pressure gas-discharge devices. The priority area of use is lighting of streets, enterprises, garages and workshops for industrial use. DRLs are used where a high luminous flux is needed, and there are no special requirements for the quality of color rendering.
Main functional parts:
- Flask.The outer shell of the device is made of heat-resistant glass. Inside there is a quartz burner, to which conductors are connected.The docking of the electrodes with the 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 coated with phosphor.
- The base.Responsible for receiving electricity from the network by connecting a point and threaded contact with the cartridge mounted in the lamp.
- Quartz burner.The main functional element of the mercury lamp. Structurally, this is a quartz bulb in which electrodes are placed on both sides: two main and two additional ignitors.
The space of the flask under pressure is filled with an inert gas, which provides insulation of heat exchange between the internal medium and the burner. Additionally, there is literally added a drop of mercury. In the cold state, the mercury compound looks like a deposit on the flask or has the shape of a ball.
Principle of operation: the essence of transient processes
The action of an arc mercury lamp is based on the processes of electrical discharge in a gaseous medium occurring in a flask under high pressure.This generates a glow source in the manner of a spiral in an incandescent bulb. But it is not a red-hot tungsten filament, but a cord of luminous mercury vapor, “stretched” between the electrodes.
The steady glow of the DRL-lamp starts 8-10 minutes after the power is applied. During this time, the current flowing in the lighting device is above the nominal value, and is limited by the resistance of the control gear.
The duration of the start-up depends on the ambient temperature - the colder, the longer the lamp “warms up”. After turning on, mercury slowly evaporates during heating and gradually increases the discharge between the working electrodes. When the mercury component completely turns into a gaseous form, and the pressure inside increases, the light bulb will reach the maximum light output.
Voltage arc in mercury vapors creates a glow of unacceptable color reproduction of predominantly blue-green hues.The phosphor is responsible for converting UV radiation to red tones of light. The combination of colors gives a white cold glow of the DRL light bulb.
Application specifics: pros and cons of lamps
DRL type illuminators are mainly installed on poles to illuminate streets, carriageways, park areas, house territories and non-residential structures. This is due to the technical and operational features of the lamps.
The main plus of mercury-arc devices is high power, providing high-quality lighting of spacious areas and large objects.
Additional advantages include:
- Durability.The average term of work declared 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 decisive parameter when choosing a lighting device for the street. Discharge lamps are frost-resistant and retain their performance at sub-zero temperatures.
- Good brightness and lighting angle.The light output of the DRL devices, depending on their power, ranges from 45-60 Lm / V. Thanks to the quartz burner and the phosphor coating of the bulb, a uniform distribution of light with a wide scattering angle is achieved.
- Compactness.The lamps are relatively small, the product length of 125 W is about 18 cm, the device of the 145 W is 41 cm. The diameter is 76 and 167 mm, respectively.
One of the features of the use of DRL illuminators is the need to connect to the network through a choke. The role of the intermediary is to limit the current supplying the light bulb. If you connect a lighting device bypassing the throttle, then due to the large electric current, it will burn.
A number of drawbacks limit the use of DRL lamps in everyday life. Significant cons:
- 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 drops by 20% or more from the nominal value, it is impossible to turn on the mercury lamp, and the luminous device will go out. At decrease in an indicator by 10-15% - brightness of light worsens by 25-30%.
- Noise at work.DRL-lamp emits a buzzing sound, not noticeable on the street, but tangible in the room.
- PulsationDespite the use of a stabilizer, light bulbs flicker - it is undesirable to perform long-term work with such lighting.
- Low color rendition.This parameter characterizes the reality of perception of surrounding colors. The recommended color rendering index for residential premises is at least 80, optimally - 90-97. In DRL lamps, the indicator value does not reach 50. With such lighting it is impossible to clearly distinguish between shades and colors.
- Insecurity of use.In the process of work, ozone is released, therefore, when using the lamp inside the building, an organization of a high-quality ventilation system is required.
In addition, the presence of mercury in the flask is in itself a potential hazard. Such bulbs after use can not be simply thrown away. In order not to pollute the environment, they are disposed of properly.
Significant minus DRL illuminators - the inability to re-turn to the full cooling of the lamp. When the device is operating, the gas pressure inside the glass bulb increases significantly (up to 100 kPa). Until the lamp cools down, it is impossible to pierce the spark gap by starting voltage. Re-start occurs in about a quarter of an hour.
When determining the optimal variant of the lighting device, the following characteristics should be taken into account:
- cap shape / size;
- brightness of the light flux;
- the duration of the 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 lanterns - the bigger it is, the more efficient the lamps should be.
Light flow.The main indicator of light radiation, directed in different directions. The parameter is measured in lumens (Lm). It is for this criterion, and not for power, that it is necessary to compare the performance of different types of lamps.
Significant savings on energy - a weighty argument in favor of LEDs. The high cost of LED-lamps pays off in the first year of operation.
The base.DRL illuminators are available with the two most popular types of caps:
- E27 - a screw form, diameter - 27 mm. This basement is equipped with mercury-arc devices for 80 watts and 125 watts.
- E40 - the largest size category "E". Cap 40 mm is used in lamps of 250 W and above, designed to illuminate a spacious area.
In addition to the type of "twisting" the cartridge, you should take into account the dimensions of the ceiling of the lamp.
Duration of service.This parameter is largely determined by the quality of production, namely the responsibility of the manufacturer. It is better to choose a lamp with a maximum period of service. As a rule, high-power devices have a longer service life.
Part of the information about the characteristics of the lamp laid in the labeling. In domestic practice, the literal 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 such as DRL according to the international system ILCOS are marked QE. Some manufacturers adhere to the common European ZVEI and the German LBS order of designation.
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 built-in ballast, QG - spherical flask, QR - lamps with a reflective inner layer.
Which manufacturer to give preference
It is recommended to choose products of famous brands, it is better to refrain from buying cheap “nameless” Chinese light bulbs.The following manufacturers of mercury illuminators gained trust among customers:
- Osram (Germany);
- Philips (Netherlands);
- General Electric (USA / Hungary);
- Next (Poland);
- Eurosvet (Ukraine);
- Lisma (Russia);
- DeLux (China).
In the European market, two brands are considered leaders in the production and sale of lighting products: Osram and Philips. Both companies have years of experience - more than a century, a wide range and a developed sales network.
Factories of the American company General Electric are located in Europe. The quality of goods and the duration of service is not inferior to previous brands, and the price is slightly lower. For the DRL illuminator with a power of 250 W, you have to pay about $ 7.
E.Next is an electrical holding, where the main manufacturer of devices is the Polish group of companies Tarel. In the product line are numerous series of different lamps for home, street and industrial lighting.
Lights of E.Next at 250 W compared with German and Dutch lamps of similar power, are inferior to competitors in color reproduction (Ra = 40) and service life (12000 hours). Estimated price - 5 cu
Mercury-arc lamps of Russian, Ukrainian and Chinese brand production are in the same pricing policy, the average cost of products at 250 W - 3 cu. The disadvantage of lighting devices is the limitations of their work - according to the passport data, the light bulbs will last 5000 hours.
Comparison of DRL bulbs with analogues
Discharge lamps are often compared with each other and with more advantageous LEDs. The closest analogues to the DRL are the three types of lighters: DRV, DRI and DNaT. Let's try to identify the features and competitive advantages of different light bulbs.
DRVMercury-tungsten arc lamp in design and principle of action is very similar to the DRL. Structurally inside the flask there is a mercury discharge torch and a tungsten coil. The last element limits the strength of the current for the burner, which means that additional ballast equipment is not needed.
The main differences of mercury-tungsten lamps from DRL:
- consume more electricity - the luminous flux of the DRV 250 is not more than 5500 Lm;
- estimated work time - 3000 hours;
- light up within 1 minute.
DRI.Arc mercury lamps with radiating additives: halogenite of indium, sodium, waist, etc. Metal components increase the light output of devices to 75-90 Lm / W.
DnatSodium arc lamps can boast maximum light output and a long operating period among the discharge illuminators. The performance of sodium light bulbs over time is not reduced as much as DRL lamps.
Characteristics of HPS:
- maximum light output - 125 Lm / W;
- operability - within 20 thousand hours;
- relative stability of parameters;
- wide range of operating temperatures;
- output at maximum illumination in 5-7 minutes.
Cons of sodium sources of light: a significant ripple and low color rendering coefficient, Ra = 25. The emission spectrum is dominated by red and yellow colors.
Discharge lamps surely give way to LED lamps.LED-devices in all technical and operational parameters are superior to their predecessors.
The undeniable advantages of LEDs: environmental friendliness, minimal ripple, long service life, instant switching on, excellent color rendering and contrast. In addition, such devices have temperature and mechanical resistance.
Requirements for the disposal of mercury devices
Thoughtlessly throwing out waste or reject mercury-containing light bulbs is impossible. Devices with a damaged bulb are a serious threat to human health and the environment in general.
The question of how to dispose of unsafe waste is relevant both for business owners and for ordinary residents. Recycling of mercury lamps are engaged in organizations that have received the appropriate license.
An enterprise enters into a service contract with such a firm. According to the application, a representative of the recycling company leaves the facility, collects and removes lamps for subsequent decontamination and recycling. The estimated cost of the service is 0.5 USD for one lighting device.
If the discharge of mercury-containing lamps by enterprises is somehow controlled by the supervisory authorities, then compliance with the rules for disposal 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 effects of mercury vapor in the surrounding atmosphere.
Conclusions and useful video on the topic
The proposed video review describes the design of the DRL illuminator, describes in detail the principle of operation and highlights the main operational details:
DRL-type discharge lamps are still used in street lighting. The main argument in favor of mercury devices - a powerful luminous flux and affordable cost. However, they are gradually being superseded by more advanced lamps, which, along with high efficiency, can boast of good luminescence quality and safety of use.