Underground Light: AtomSvet Illuminates Mosmetrostroy Tunnels
Metro tunnels are in use 24 hours a day. It means that materials used in their construction and operation have to meet higher reliability and safety requirements. Selection and positioning of lighting play an important role, since artificial lighting is the only source of light and the main safety factor at any time of the day.
There are several criteria for selection of lighting systems for metro tunnels: for example, a light level of not less than 10 lx for a segment of the tunnel and not less than 50 lx for maintenance of equipment. Furthermore, light sources for tunnels must have a long service life without loss of lighting quality and with a high degree of dust and moisture protection (not less than IP 54).
Conventional filament lamps are used in the majority of metro tunnels. These light sources have a number of disadvantages which are absolutely at odds with the lighting requirements for such facilities. Filament lamps have a low luminous efficiency, while no degree of protection makes them highly vulnerable in the environmental conditions of metro tunnels: dust and dirt deposits heat up and then dry out and then the cap sticks in the socket which makes it difficult to replace a failed lamp. As a result, low-cost conventional filament lamps are an ineffective and costly light source for underground facilities.
Conventional light sources have been replaced by advanced industrial LED based lighting systems in order to maximize tunnel lighting while saving as much money as possible. These lighting systems are protected from overheating and short circuits. Their use enables power consumption to be considerably reduced and possible electrical overload to be prevented.
A top quality and reliable industrial lighting fixture must show the ultimate durability and robustness since it is designed to operate on a continuous basis. It must also show excellent lighting performance, providing savings on lighting because of the low power consumption and, not least, it is almost maintenance-free throughout its operational life due to a high degree of dust and moisture protection (normally, IP 67). The estimated lifetime of continuous operation is not less than 50,000 hours, which equals 12 years of service life.
LED product units manufactured in Russia meet strict lighting requirements for tunnels. High-quality LED based lighting fixtures are not produced in China; neither do they contain Chinese components.
The operational efficiency of LED based lighting systems in metro tunnels can be illustrated by AtomSvet’s long-term project for OAO Mosmetrostroy.
Project work was started by AtomSvet as early as in November 2012. Because of the high humidity Mosmetrostroy faced a serious challenge of lighting a segment of the main line tunnel under construction. All conventional light sources failed after a short time; thus it was necessary to find a good substitute. The main criterion for selection of new lighting devices was reliability of the equipment and its failure-free operation in severe conditions of high humidity.
AtomSvet ran a trial of four 22W lighting fixtures of the AtomSvet® Plant LV low-voltage series. The trial lasted for four months during which the lighting systems proved themselves.
Based on the results of the trial, a pilot project was started in the Building & Construction Department No.11 of Metrostroy LLC. More than 400 low-voltage lighting fixtures were delivered by AtomSvet. Over several months the energy saving was measured in kilowatts by the chief power engineer of the Building & Construction Department as part of testing. After the trials it was concluded that the payback period of AtomSvet lighting systems is around 7 months for the tunnel segment 1.3 km long. And the cost saving was around 2.5 mln rubles.
“Since transformers in a section of about 300 m supply 36 V to filament lamps, there is a significant voltage drop at the end of the tunnel,” says Sergey Katin, Low-Voltage Equipment Project Manager of AtomSvet LLC. “To ensure that the luminous flux complies with the lighting requirements throughout the tunnel, technical specialists increased the output voltage to 45 V at the construction site, thus, leading to additional power consumption. The use of AtomSvet lighting systems, which consume 3.5 times less energy than filament lamps, enabled the voltage drop in this section to be minimized. It should also be noted that AtomSvet produced a batch of project-specific lighting fixtures – with an increased voltage threshold of 50 V (the standard threshold is 36 V).”
This measure ensured the full compliance with the lighting requirements and helped to save money and energy: if filament lamps were used, Mosmetrostroy would have to install intermediate transformers every 300 m with an output voltage of 45 V. When AtomSvet low-voltage lighting systems are used, intermediate transformers are installed at every 450 m with an output voltage of 36 V.
“In July 2013, during construction of the line in the Likhobory depot, more than 200 AtomSvet ® Plant LV LED based lighting systems were installed with an operating voltage of 36 V,” – says Igor Rudenok, chief power engineer of Building & Construction Department -1 of Metrostroy LLC. “As a result , the lighting quality increased to 200 lx (50 lx are required); in shaded areas it was not less than 100 lx. Furthermore, power consumption load was 5 times less in the lighting network and thus power consumption was also reduced. It was estimated that savings on power costs for the lighting network of tunnels 5.6 km long in the Lublinska-Dmitrovka subway line using AtomSvet LED based lighting systems at the end of construction will be not less than 9.3 mln rubles.”
The above examples show that AtomSvet LED lighting systems can reliably replace conventional light sources and, ultimately, help to make big savings. So far more than 800 AtomSvet®Plant LV 31 W lighting systems have been supplied for Mosmetrostroy’s needs.
It is planned to continue and extend cooperation between two enterprises, not only regarding the application of low-voltage equipment. AtomSvet has already delivered its standard AtomSvet® Plant 220 V lighting systems for a number of subway construction sites for the purpose of security lighting and area illumination instead of mercury arc lamps and metal halide lamps.
Can't decide?Contact our manager
or fill out the form on the web site
and we will try to help you out?