Low voltage electrical installations
Low voltage electrical installations (0 – 0,4 KV) , interiors and exteriors. Companies whose products we use:
Low current installations
Fire detection and signalization systems
The fire is a complex phenomenon, which has a random character and an uncontrolled evolution. Because of its violent nature, it represents a constant danger for us. In many cases fire produces the loss of human lives and produces great material losses. In order to avoid these disasters, the buildings are equipped with fire detection and signaling systems. The role of these installations is the continuous surveillance of the protected space, the correct fire detection, and the activation of the alarm system in case of fire. Such a system has the following components: signaling central unit; automatic detection of smoke and temperature; manually signaling buttons; sonorous and visual warning; the circuitry of the system. Besides the warning operations, the installation is capable to activate the following functions: lock of anti-fire doors; turn on the smoke and hot gases evacuation system; shutdown the supply of electrical energy; shutdown the climate system; automatic alarm through telephone line; start the extinguisher, open evacuation doors etc.
Efraction control, acces control
The requirements of a well-designed alarm system are as follows: reliable reaction in the shortest time possible; minimal rate of false alarms; announcement of the intervention institutions in the shortest time; possibility of post-event analysis in order to recover some of prejudices; and to improve the prevention methods for unwanted events.
The functions of surveillance are: surveillance of an open space; surveillance of a delimited space (attack from exterior on the walls, windows and doors); presence surveillance in a closed space (room, hall).
Detection methods of burglary attempts: detection of door and window openings using magnetic, inductive, or mechanic contacts; aggression detection with the help of buttons or panic pedals; infrared and microwave movement detection; windows breaking detection with active, passive, and acoustic methods; detection of wall penetration with vibration detectors.
In general there are two identification methods used in the access control systems: the use of an ID which is in the possession of the solicitor and the use of a biometric ID.
ID manufacturing technologies: magnetic cards – in order to read the card, it has to be moved in front of a magnetic reader device; proximity cards – reading the card doesn’t require physical contact with the reader; Wiegand effect cards – contain conductors in layers with variable thickness, and send impulses to the reader when they are in magnetic fields; smart cards – contain built-in microprocessor and offer a high level of security.
Biometric ID methods: fingerprint analysis; palm analysis; voice recognition; physiognomy recognition.
Surveillance systems with Closed Circuit Television
Closed circuit TV surveillance systems are made up by using black & white or color cameras, switches, monitors, and acquisition boards for computers depending on the demands and the location of use. The complexity of these systems is determined by the components which are used. The most important component of these systems is the camera, which has the following characteristics:
- Resolution – the camera’s capability to reproduce images in detail (typical medium resolution is 380 lines for a black & white camera and 330 lines for a color camera);
- Sensibility – the camera’s ability to function in low light conditions (the higher is sensibility the lower is Lux level);
- Lenses – with fixed or variable focal length;
- Supply voltage 12Vcc, 220Vca.
Images can be recorded using a DVR (Digital Video Recorder) or directly on a computer’s hard disk drive.
The image switchers are used when the images from two or more cameras are viewed on one monitor. The most known one is the analog video switcher. Several video inputs can be individually selected with the press of a button.
The monitors are used to visualize the images captured by the video cameras or those recorded.
One of the important functions of the cable TV systems is to provide the possibility to watch different TV shows at the same time in various places.
The main components of the systems are: cable TV entry signal amplifier, section distributor, line amplifiers, distribution network made up by using derivers and splitters; connection elements: couplings, plugs etc.
When placing a cable TV system, are taken into consideration the room numbers, lines length, signal level, signal loss from derivers, splitters and coaxial cables.
The telephone lines have already UTP cables (FTP), the phones are analog or digital, or IP phones. A computer network is not simply just a data network, from the software settings can be selected which plug will be used for the computers and which one for the phones.
One of the important functions of the sound system is that provides the possibility to address to a large group of people at the same time with a minimal effort. Sound systems are used to make announcements for clients or employees, to play ambient music or to make emergency announcements.
At the beginning, such systems were made up by using: a microphone or sound source unit; mixing unit; amplification station; loudspeakers network, boxes; volume adjustment elements, power supply source. Nowadays sound systems can be integrated in complex multimedia systems that makes possible video conferences, remote control etc.
PA Audio - Video
The traditional sound systems have been already changed by audio – video systems, with audio – video servers in rack, which may have several independent areas in the building. This allows the storage of more movies and audio albums – from which the customer is allowed to pick which one he/she wants – along with TV channels, Blue-ray, DVD and radio stations. In each zone can be selected an audio / video source, independently of other areas.
Industrial Automation for operation lines, water plants, wastewater treatment plants, SCADA, Factory monitorizing(BMS) and so on.
Companies whose products we use:
- Phoenix contact
BMS provides more comfort and less energy consumption.
The electricity which is implemented in today’s buildings in general is not up-to-date. Of course we are not talking about electrical equipment such as TV, phone, fax, or computer, but the energetic network of the building. While the development of the hidden components is performance oriented, the development of the visible components (e.g. switches, plugs) is advancing toward a better aesthetics. Even if the TV remote control is a common thing for everyone, the concept of remote controlling in a building is still rare. But let’s ask the following question: would we buy a TV without a remote control today? Today’s world is full with such systems and services, which are already basic requirements. For this reason it was necessary to integrate our buildings in a well-designed automation system. We want to automate our buildings (factories, institutions, and houses) by mounting various mechanisms which can react in an intelligent way to different exterior influences such as sunlight, rain, or temperature variation. Doing this we can achieve a pleasant relationship between man, nature, and functionality.
A comparison between the electrical installations used in past years and today’s demands reveals that there are major differences. If until now it was enough if we could turn on/off or switch on/off, it is not anymore. Nowadays we need other, more sophisticated functions like administration, command, surveillance, energy, and time management. At this point the traditional technics reach their limits. The functional networks are isolated - lacking communication with each other - and they also require a big amount of wiring which leads to high costs and an increased fire risk. In contrast, the bus systems are much more economical and well developed. They allow high speed data transfers using just one communication cable. In this way the system is capable to react to different events that may occur.
There are more than one specialized systems for BMS, such as: KNX, LAN, and so on. In the last years, from KNX system has been developed the KNX open system, also known as KNX . For its capacity to include all automation systems, it became an international standard: ISO/IEC 14543-3 (for details see www.konnex.org).
The need for a greater flexibility, comfort and minimal energy consumption has led to the development of a building surveillance system. The bus technique used in these systems is regulated by KNX . The producers that are KNX members guarantee the compatibility of their products with the bus system. In this way it’s possible to use products from different KNXA member companies in the same bus system. While the traditional electrical installations reach their limits, the achievement of a greater comfort and the aspiration for more and more functions in electrical installations can be solved in a clear and economical way with the Instabus system.
Some of the KNXA member companies: ABB, Stotz-Kontakt, AEG, Busch-Jaeger, Gira, Grasslin, Kopp, Legrand, Merten, Siemens, Zumtobel.
Corelaton with KNX devices
In the past few years there has been a significant increase regarding the requirements of electrical installations, especially in the industrial and banking sectors, but also in office buildings and hotels. Here we name just a few of them: comfort, low prices, short installation time, dynamics, and security.
In order to satisfy these requirements a higher data transfer is needed, which in the case of traditional installations leads to a significant wiring increase. In this way the error spotting and correcting would be too hard and the installation prices would go up. The traditional systems are isolated ones, where the components lack communication with each other, unless a substantial technical and financial effort is made.
Despite the multiple demands the KNX accomplish, the system remains economical and clear in construction. All the communication between the components in order to achieve different functions (command, control, surveillance, and signaling) is done with bifilar cable (two wire cable). The components from the bus are connected to these cables. The information reaches the components in a digital form, a telegram data. Every component receives this telegram, but only that one reacts to it which finds its address in the telegram.
Areas of utilization
Lighting control and surveillance: general illumination; automatic light control depending on light conditions, time (day, week, or year), or presence; manual control; on/off, dimming; centralized control; safety illumination.
Blinds control: centralized control depending on wind speed, weather, illumination, snow, ice… and so on; manual control; positioning.
Climate and ventilation control: control in rooms depending on humidity, weather; air introduction and extraction control, depending on humidity, temperature, air quality; temperature supervision and signaling control.
Surveillance, signaling, and data acquisition: centralized and unique commands; display and pushbuttons for user interface; computer visualization and control with dedicated software.
Fire alarm: optical and ionization sensors; warning in case of temperature increase; alarm through dispatcher or telephone.
Burglary alarm: infrared presence sensors; door/window opening/break signaling; phone alarm.
Access control: access with card or personalized code.
In factories it is also possible the registration and surveillance of different temperature or pressure values, leakage and level signaling, and so on. The use of the KNX system is worthwhile especially in the case of factories, banks, hotels, and office buildings. In the case of particular houses the investment is recovered in more than 5 years. The economical functioning can be observed when besides the illumination control the climate control (separated in rooms) and the load management at the consumers is also included.
A comparison of the KNX system with the traditional installation
The KNX system brings the following advantages:
Modern technology: Using the new information technologies, the system represents the modern technology with its properties and multiple functions.
Hierarchic and decentralized construction: The KNX system doesn’t need a central processing unit, because each component of the bus has its own intelligence. There are 3 different levels in the system: (1) component; (2) line (containing up to 64 components); (3) zone (containing up to 12 lines) and the system which is made up by max. 15 zones. A short circuit on a line or a voltage drop will not influence the other lines because of the hierarchic construction of the system. This leads to an increased reliability of the system. Except the power supply of the components (done through the bus cable), the information exchange is separate. The information is transmitted from a line to the other only if the recipient is present on the other line, in this way solving the collision of information. The fluent, error free functioning of the system depends on the design as well.
Economical functioning of the building: Using the KNX system and implementing the energy management makes possible to lower the operating cost of the building. At the same time with optimal energy usage we can preserve the environment.
Bigger flexibility: It is easy to reprogram or to reposition the components, if the functionality of the building changes or if we want to change some of the existing functions.
Extension of the system is made easily: The system can be implemented in a building in several steps (years or floors). It is also possible to extend the system.
Easy design and installation: Because of its topology, the design of the KNX system becomes an easy task. In this way it’s possible to make shorter the installation period.
Lower fire risk: The amount of cables in the system is smaller, which lowers the fire risk.
Compatible components: Thanks to KNXA the components from different member companies can be replaced depending on the preferences.
Remote control: The system’s components can be controlled by infrared, and in some cases the data transfer by infrared connection is also possible. There are also components which can receive commands through Internet.
Nowadays, the KNX system control from distance can be made through Smart Phones.
Napa Impex Ltd designs and executes any type of project, starting from particular houses up to photovoltaic parks of several megawatts.