Street lighting plays a huge role in human life. Thanks to the lanterns, the movement of people and cars in the dark becomes safer and more comfortable. A condition for the effective operation of street lamps is the presence of a special device that turns them on and off in accordance with a given mode. Most often, the role of such a device is performed by a photo relay FR-601 or similar models.
Content
- Street lighting
- Sources of light
- Photo relay device
- Characteristics of different IEK models
Street lighting
To organize lighting on the streets of cities, lamps are used, fixed on poles. They are activated in two ways: manual and automatic. Manual control is carried out by specialists who are constantly on duty at the control room.
Automatic adjustment is more convenient because it allows you to control the level of illumination using timers or sensors. In this case, the constant participation of a person is not necessary.
There are very serious requirements for the luminaires installed on the streets. They must be of high quality, reliable and safe for others. The service life of such devices should be quite long. These conditions are fully met by LED lamps. Halogen, fluorescent and incandescent lamps can serve as a worthy alternative to them.
Outdoor lighting installed in different places has certain characteristics. Lanterns are used to illuminate:
-
Major roads and highways. For this, the devices are equipped with a reflector that concentrates the light beams in one direction. For the purpose of economy, lighting structures are mounted at a high height and a considerable distance from each other. - Roads of secondary importance. To increase visibility, lamps with reflectors or lamps of diffused light are used. The transparent cover of the shade diffuses the rays over long distances.
- Pedestrian sidewalks, bike paths and parks. They are illuminated only by diffused light. Lanterns have shades in the form of a cylinder or a ball with transparent relief rings. The power is determined by the distance at which the supports are located.
When installing various information objects (signboards, banners, billboards, etc.), artificial lighting is also used with the help of spotlights and special-purpose lamps. Traffic signs and house numbers are highlighted in the same way.
Sources of light
The light that illuminates streets, roads and houses must have a high brightness and degree of diffusion.. There are several options for luminaires with the following characteristics:
-
Oil. They were used for a long time, they worked at the expense of burning oil. - Kerosene. They use the principle of burning kerosene. The wick present in the lantern is placed at one end in a container with fuel, at the other end it is clamped by the burner mechanism.
- Gas. They give light during the combustion of lamp gas, as well as hydrogen, methane, propane, etc. Previously, they were often used for street lighting, now they are used by tourists as portable lamps.
- Incandescent lamps. The glow comes from an incandescent body that is heated to a very high temperature by electricity. Part of such a lamp is a tungsten coil, protected from external influences by a glass bulb. Previously, vacuum flasks were used, now they are filled with an inert gas to minimize heat loss.
- Arc. Lighting in them occurs due to an electric arc that takes place between two electrodes. The arc lamp can be filled with inert gas, metal or salt vapors. Depending on the properties of the filler, the light spectrum is different.
- Induction. Plasma serves as a source of light radiation in them. Its formation occurs due to the ionization of the gas under the action of a high-frequency magnetic field. Induction-type lamps can work from 60 to 150 thousand hours, the number of on / off switches in them is unlimited. They show a high degree of light transmission even after long-term use, turn on and off with lightning speed. After the end of their service life, they must be disposed of.
The most modern source of street light is a new generation of devices - LED lamps. With their help, it is possible to achieve tangible savings, reducing the amount of electricity consumed from 2 to 10 times. Such lamps are compact, resistant to mechanical damage and weather changes, and durable.
In the design of a street lighting device, an important role is played by the support. It is carried out in the form of a concrete, metal (less often - wooden) post, mast, cable or fixing cable.
Photo relay device
The design of modern street lamps provides for a device that allows them to automatically regulate their work. Such devices are called photo relays. They are based on a built-in switchboard or remote sensor. The latter is located in a separate sealed case, characterized by increased protection against adverse external factors.
Most relays have a programming function. It allows you to turn off and on the lights at different times depending on the season. Thanks to the preset programs, the lighting is automatically switched off earlier in summer than in winter.
In addition to the automatic mode of operation, the devices have a manual control method. With the help of a built-in switch, a specialist servicing the equipment can independently control it in the event of emergency situations or for the purpose of preventive checks.
Different photo relays have different sensitivity, which, when connected, is regulated using different resistances. The shutdown threshold is regulated by a resistor that controls the initial voltage.
The field of application of devices based on photosensors is very wide. Photo relays with certain properties are used in different fields.
A device containing a photosensitive element inside a housing automatically turns on the lighting at dusk and turns it off at dawn. It has a transparent and durable body that allows it to react to sunlight and at the same time protects it from damage.
Some relays of this type are additionally equipped with a timer. On it, you can fix a specific time period, after which the mechanism will be triggered, turning on or off the lighting. Timers can have different programmed intervals. In some models - an hour or a day, in others - a week, in others - a year. This allows you to distinguish between different periods (not only day or night, but also holidays and weekends).
In some devices, the response threshold can be adjusted using a special switch. When it is set to positive, the photocell will be triggered by the slightest blackout (in a thunderstorm, cloudy weather). When switched to minus, it is only activated at night.
Characteristics of different IEK models
Manufacturers of devices intended for lighting control produce various models of light relays, differing in technical characteristics and properties. The FR-601 brand device with a diameter of 63 mm and a height of 77 mm is widely used. It is intended for use in a single-phase AC power supply with a voltage of 230 V and a frequency of 50 Hz and consumes 0.45 W. Illumination in it is regulated in the range from 5 to 50 lux.
According to user reviews, FR 601, also called twilight switch, is easy to install and operate, and is inexpensive, suitable for indoor lighting control, as well as highlighting shop windows, advertisements, etc.
Another type of photo relay for street lighting - IEK FR-602 - has a similar operating principle. Its body, made of non-combustible plastic, contains a board with functional elements - a variable resistor, a diode, a control relay, a photoresistor and two transistors. The casing of the device with a remote sensor is airtight and highly durable. FR-602 is used to illuminate the entrances of multi-storey buildings, public buildings, enterprises, entrances to private territory.
