General information about DRL lamps
Mercury lamps of high pressure (AML (arc mercury luminiferous type are used to lighting of streets, workshops of the industrial enterprises and other objects which are not demanding the quality color rendition).
Device: The lamp of DRL (fig. 1) consists of the glass cylinder 1 supplied with the threaded socle 2. In the center of the cylinder the mercury-quartz torch (tube) 3 filled with argon with mercury drop additive is strengthened. Four electrode lamps have the main cathodes 4 and additional electrodes 5 close to the main cathodes and connected to the cathode of opposite polarity via the additional coal resistor 6.
Additional electrodes, facilitate ignition of the lamp and do its work to stabler.
And now is more detailed:
- The socle represents the simple design which allows to accept the electric power from the network circuit due to engagement of current carrying parts of the lamp of DRL (one of which threaded, and the second — dot) with electrical links of the boss of the lamp. Therefore electric power transmission on torch electrodes is carried out.
- The torch (quartz) is, perhaps, the main functional part of DRL of the lamp. The torch represents the quartz flask which on the parties has about two electrodes. Two of them the main and two - additional. The internal space of the quartz torch is filled with gas "argon" and mercury (the small droplet of mercury).
- The flask (glass) — is the external part of DRL of the lamp. The quartz torch of the lamp which the electric conductors going from the contact socle approach is placed in it. From the glass flask all air then nitrogen is pumped is pumped out. In the glass flask two limiting resistance (standing in the chain of additional electrodes) are located. DRL lamp flask from the inside has the phosphor.
One of the first lamps of DRL had only two electrodes in the design. It worsened conditions for commission of the arson of the lamp and demanded the additional device of start-up (pulsed high-voltage breakdown of the interval of the torch). Such kind of lamps of DRL was laid off also the zamenyona on the 4th electrode option. Needs only the throttle.
Principle of action
The torch (RT) of the lamp is made of high-melting and chemically resistant transparent material (the quartz glass or special ceramics), and filled with strictly dosed portions of inert gases. Besides, metal mercury which in the cold lamp has the appearance of the compact ball is entered into the torch, or accumulates in the form of the raid on walls of the flask and (or) electrodes. The column of electric electric discharge is shining bodied RLVD.
Process of ignition of the lamp equipped with the lighting electrodes looks as follows. When giving on the lamp of power voltage between close located the basic and the lighting electrode there is the glow discharge that is promoted by small distance between them which significantly less than a distance between the main electrodes, therefore, is lower also breakdown voltage of this interval. Emergence in the cavity of RT of rather large number of charge carriers (free electrons and positively ionized atoms) promotes breakdown of the interval between the main electrodes and ignition between them the glow discharge which almost instantly passes into arc.
Stabilization of electric and light parameters of the lamp occurs in 10 — 15 minutes after inclusion. During this time lamp current significantly exceeds rated and is limited only to resistance of the puskoreguliruyushchy device. Duration of the starting mode strongly depends on ambient temperature: the more cold, the lamp will longer inflame.
Electric discharge in the torch of the mercury arc lamp creates the visible radiation of blue or violet color and also powerful ultra-violet radiation. The last excites the luminescence of the phosphor put on the internal wall of the external flask of the lamp. The reddish luminescence of the phosphor, mixing up with the white-greenish radiation of the torch, gives the bright light close to white.
Voltage variation of the power line in the big or smaller party causes corresponding change of the luminous flux. The deviation of power voltage for 10 — 15% is admissible and is followed by change of the luminous flux of the lamp for 25 — 30%. At reduction of supply voltage less than 80% rated, the lamp can not be lit, and burning — to go out.
When burning the lamp strongly heats up. It demands use in light devices with arc mercury lamps of heat-resistant wires, imposes serious requirements to quality of contacts of cartridges. As pressure significantly increases in the torch of the hot lamp, also tension of its breakdown increases. The size of tension of the power line is insufficient for ignition of the hot lamp. Therefore before repeated ignition the lamp has to cool down. This effect is the essential lack of arc mercury lamps of high pressure as even very short-term break of power supply extinguishes them, and repeated ignition requires the long pause on cooling.
General information: Lamps of DRL have high luminous efficiency. They are steady against atmospheric actions, their ignition does not depend on ambient temperature.
- lamps like DRL are issued 80, 125, 250, 400, 700, 1000 W;
- average term of service of 10000 hours.
Important lack of lamps of DRL is intensive formation of ozone in the course of their burning. If for bactericidal installations this phenomenon usually is useful, then in other cases concentration of ozone near the light device can significantly exceed admissible on sanitary standards. Therefore rooms in which DRL lamps are used have to have the corresponding ventilation providing removal of excess of ozone.
O0dr-osnovnaya throttle winding, D0dr-dopolnitelnaya throttle winding, C3-noise suppressing condenser, SV-selenovy rectifier, R-shooter resistor, L-two-electrode lamp of DRL, R-discharger.
Inclusion: Inclusion of lamps in network is carried out by means of PRE (the pusko-regulating equipment). In usual conditions consistently with the lamp the throttle (scheme 2) joins, at very low temperatures (it is below -25 °C) the autotransformer (scheme 3) is entered into the scheme.
At inclusion of lamps of DRL the big starting current is observed (up to 2,5 · I). Process of the razgoraniye of the lamp lasts up to 7 minutes and more, repeated inclusion of the lamp is possible only after its cooling (10-15 minutes).
- specifications of the lamp of DRL 250 Power, W - 250;
- lamp current, A - 4,5;
- socle type - E40;
- luminous flux, Lm - 13000;
- luminous efficiency, Lm/W - 52;
- color temperature, To - 3800;
- burning term, h - 10000;
- color rendering index, Ra - 42.
On the basis of lamps of DRL are developed and metallic-halogen lamps into which enter different iodides of metals that allows to receive the corresponding chromaticity of visible radiations are issued and to increase profitability of work of the lamp. The release of lamps of DRV, DRVED with the built-in active ballast is mastered. Such lamps join as normal glow lamps.Top