Nejnavštěvovanější odborný web
pro stavebnictví a technická zařízení budov
estav.tvnový videoportál
Elektrotechnika
Archiv článků od 28.4.2014 do 26.10.2015

Archiv recenzovaných článků

zpět na aktuální články

26.10.2015
Tomáš Krempaský, RevizeKontroly.cz

Owners of residential buildings and their tenants must ensure the implementation of some activities on the technical and fire safety devices in order to ensure their safety and functionality in use. Inspections and checks are therefore not just binding on the applicable regulations, but also may prevent damage to health and property.

22.6.2015
Ing. Andrea Nasswettrová, Ph.D., Ing. Pavel Šmíra, Ph.D., Ing. et Ing. Soňa Křivánková

The paper presents the Acoustic Pack device which can record sound emitted by wood-destroying insect larvae while eating wood mass. It records the sound with up to eight sensors at once in several-hour records using high quality acoustic signal recording system. While detecting, it is also possible to hear an activity on a certain element in the structure. This makes it possible to obtain a complete view of the condition of elements with a graphic output of the activity and sound records. Thanks to these advantages, the acoustic system has become a great helper in the detection of damage and in the status analysis of attacked elements in the structure.

15.6.2015
Ing. Aleš Vodička, Ing. Pavel Mlejnek, Ph.D, Ing. Jan Včelák, Ph.D., Ing. Petr Ptáček, Ph.D., doc. Ing. Petr Kuklík, CSc.

The article describes one of the key factors affecting the lifetime of a wooden building – moisture. It shows the most common causes and effects of increased moisture inside a wooden construction. Methods of determining moisture level in it are listed and particular one suitable for continual monitoring is presented. The suitable method is measuring of the resistance and conversion to a moisture level. Corrections of the moisture level for temperature effects and wood type are included.

11.5.2015
Ing. Andrea Nasswettrová, Ph.D., Ing. Pavel Šmíra, Ph.D., Ing. et Ing. Soňa Křivánková

The paper presents a diagnostic method based on X-ray imaging of degraded wooden mass. The technology uses the reduction of image information to 2D planar transformation. A gained X-ray (RTG) image is processed in specifically designed programs. A result is an image which detects the degree of damage in wooden structural elements and includes statistical evaluation of degraded part share in the element. The method known from the medical or veterinary practice is based on a high-quality X-ray image of a diagnosed material and on a highly-efficient image processing.

4.5.2015
Ing. Michael Trnka, CSc.

In 2013, electric power generated in the Czech Republic in power plants using various primary energy resources reached 87.06 TWh (gross production). The gross domestic consumption was 70.18 TWh. The diagrams presented and the annual balance clearly show that the biggest electric power producers in the Czech Republic continue to be coal-burning power plants. The usage of electricity produced from renewable resources for regulation of the production is limited by the fact that these resources (FVT, VTE, biogas power plants and small water power plants) have an unlimited priority access to the distribution network and are not regulated in any way.

6.4.2015
Ing. Andrea Nasswettrová, Ph.D., Ing. Pavel Šmíra, Ph.D., prof. Ing. Pavel Fiala, Ph.D., Ing. Zoltán Szabó, Ph.D.

The paper presents results of specifically developed device for exact localization of the position behind a wall. It is intended for the construction sector where it is necessary to specify exact positions at both sides of the wall. The designed indicator uses the principle of electromagnetic field and it consists of a transmitting part and a receiving part. The transmitter emits electromagnetic waves at a specific frequency and by modulation from one side of the wall and on the other side; the receiver with an adjustable sensitivity evaluates and transmits the information to the operator of the position indicator. The described device makes it possible to detect position behind the wall against the initial point through the barrier thickness up to half a meter.

Prediktivní regulátor MPC (Model-based predictive control) využívá předpověď počasí a matematický model řízené budovy a minimalizuje plánovaný ener- getický výdej při dodržení požadovaného tepelného komfortu, obr. Domat
21.3.2015
Domat Control System s.r.o.

This year’s ISH fair (Installation, Sanitär, Heizung), held on March 10 to 14, 2015 in Frankfurt, Germany, had a slogan “Comfort meets technology”. It means that the companies aim to supply not only technologically advanced products, but also products with comfortable and easy operation. For systems and components for HVAC controls it means primarily easy-to-understand user interfaces with clean design. It showed primarily at room units, thermostats, and lights and blinds controllers with touchscreens and housings of simple shapes. Regarding system integrators, the point was in making configuration tools easy, and bringing part of the decision-making process to the engineering tools, thus cut down the engineering and commissioning time. Many booths claimed energy savings and energy management, which mostly meant classical SCADA systems and metering data acquisition, as energy management is expert activity, for which the SCADA and communication systems just provide the input data.

Domat Control System backed the hands-on experience this time. Visitors could try engineering and configuration tools at two test desks with both popular controllers (FC010, UC100, IPLC) and news like mark100 to markMX process stations range, programmable in Merbon IDE, the new engineering tool, which supports function blocks (FB) and structured text (ST) as well as compiling of customized function blocks. “Customers like especially support of standard communication protocols, like Modbus, OPC, and BACnet, together with more than 50 system drivers for third party systems, all of this well priced. The Domat components are used not only at homogenous building control systems, but also as a way how to integrate other technologies into third party SCADAs and management systems,” says Michal Šeda, head of product sales department. “With the most active distributors, Vedotech and S+S Regeltechnik, we discussed the market situation and acquired inspiration for further development.” Visitors were also attracted by a new room unit with hi-res colour touchscreen.

Domat Control System s.r.o. is Czech manufacturer of HVAC and energy control systems. The company was established in 2004, starting activities in energy management and control in 2008 by supplies of photovoltaic monitoring systems. About 55 % of the volume in 2013 was export.

16.3.2015
Ing. Pavel Mlejnek, Ph.D., Ing. Aleš Vodička, Ing. Jan Včelák, Ph.D.

The article describes sensor system for increased moisture detection in construction materials, especially in the wood. The assumption is that a sensor network is built-in into the construction elements of the building and it is connected to a central unit. The goal is to develop a sensor suitable for permanent installation in the construction during realization of the building. The sensor network enables early warning and fast detection of increasing moisture in the building and alert building owner or operator. The sensors will be placed at critical building’s locations with high risk of plumbing accidents. Using the installed sensor system it is possible approximately locate the place of failure, shorten detection time and substantially reduce damage and reconstruction costs.

26.1.2015
Ing. Martin Lahký

PID = Potential Induced Degradation refers to the physical phenomenon that causes seemingly inexplicable reduction in output from photovoltaic panels. Basically, the interlayer polarization leading to irreversible degradation of silicon photovoltaic panels. PID typically begins to appear after 2-4 years of operation, and may cause performance degradation of the solar panel according to the type and location of the panel in the string up to 70 percent. In case of an early solution, PID is reversible. PV module can be depolarize and return them almost original performance.

26.1.2015
Ing. Petr Žák, Ph.D., ČVUT FEL, Praha

We have been paying attention to the Issues of energy consumption and energy savings for many years. Due to discussion of global warming and its impacts in the last decade it is expected to implement procedures relating to energy efficiency in buildings and its evaluation in practice faster. The paper deals with the relationship between the photometric parameters and energy intensity lighting and discusses possible directions in search for energy-efficient lighting systems.

5.1.2015
Ing. Bronislav Bechník, Ph.D.

Extended concept of the term electricity storage can greatly increase the possibility of storing electricity from renewable sources at a time when their production exceeds demand. The electricity could be stored not only using conventional technologies which returns electricity (P2P – power-to-power), but in form of heat or gas too (P2H – power-to-heat and P2G – power-to-gas). While conventional technologies P2P and P2H too allow to store energy for several hours or at most days, P2G technology in conjunction with underground natural gas storage has sufficient capacity for seasonal accumulation.

22.12.2014
Stanislav Majcher, Ing. arch. Branislav Puskar, PhD.

The developed world consider the concept of intelligent building as a synonym for well-designed, built and functional building, which fully meets the requirements of operators, users and particularly satisfying residents of the building themselves. Of course, such a building is realized in high technology and equipped with advanced services and systems.

22.12.2014
Mgr. Oldřich Sklenář

This article tries to summarize the available information about photovoltaic power plants operated in the Czech Republic. Apart from describing the current situation, it is therefore concerned with comparisons between photovoltaics and other kinds of RES; the photovoltaic production according to region; the distribution of power production according to size of the installations; legal personality of the operators and international comparisons.

24.11.2014
Pavel Ševela, Bjarne W. Olesen

The goal of this paper was to inform about the development of the building integrated photovoltaic thermal (PV-T) system and evaluate its performance in compared to PV installation built of same photovoltaic cells. The study was collaboration among the Technical University of Denmark (DTU and Danish company RAcell (end-reference to website). This project was applied and optimized with the coupled house system on FOLD house, built in purpose of international student competition Solar Decathlon Europe 2012 held in Madrid in September 2012. The proposed PVT system was awarded with first price in Solar system integration sub-contest, during the competition SDE 2012.“Highly effective and innovative integration of PV and thermal systems that is not only a machine added to a house, but added value without creating too much attention to that machinery,” said one of the jury members about the PVT system, announcing the winner.
The PV-T is a hybrid system where the significant growth of efficiency of electricity generation is caused by cooling the cells to optimal temperature by system of embedded pipes on the backside of photovoltaic panels. The thermal part removes the heat, cools down the cells and increases its el. production up to 14,8 % according to PV system using the same cells in the same weather conditions. New solution was carried out for piping connection between panels. The house integrated PV-T system was compared with separate Photovoltaic and Thermal systems from energy and economy point of view. For annual usage of the FOLD house in Spain and Denmark was the PV-T system found as a more beneficial in compare to two separate systems.

24.11.2014
Ing. Roman Smékal

Classification of medical space (including inclusion in the appropriate group) must be carried out in cooperation with the responsible medical staff equipment that will use the wiring .

1.9.2014
Ing. Bronislav Bechník, Ph.D.

The history of photovoltaic begins with the discovery of the photoelectric effect in 1839 and later the photovoltaic effect in 1876. Practical application of photovoltaics came a century later, the earliest for power supply of satellites in 1958.
Turbulent development of the field followed, accompanied by the rapid decline in prices and increase of energy efficiency.

Office park
30.6.2014
Mgr. Adam Kučera, Masarykova univerzita

Modern buildings allow to unify monitoring and controlling of building automation and electronic systems under a common environment known as a Building Management System. Although in many environments the BMS represents an unnecessary feature that only improves the user experience, with growing size of the facility the BMS becomes essential for a building operation. BMS ensures a communication between users and devices and helps to significantly reduce costs of a system expansion. In that case, a reliability and an availability of the BMS becomes critical for a smooth operation. This article presents technical, methodical and process aspects of a high reliability in the BMS, based on experience with a long-term operation of the BMS at the Masaryk University. Fulfilling the presented principles enables the BMS to serve as a primary environment for controlling of the building operation.

12.5.2014
Mgr. Jiří Zilvar, redakce

Although more and more people in the Czech republic understand the principle of net metering, only a minority understands it's purpose as well. Due to Czech negative experience with uncorrected feed-in tariff is any other renewable energy support viewed with suspicion and scepticism. The article explains the purpose of net metering as non-financial mechanism of renewable energy support - what is it good for, what we can expect from it, who will benefit from it and who will carry the costs.

manažer s provozním řádem
28.4.2014
Bc. Martin Hablovič, VŠB-Technická univerzita Ostrava, Fakulta stavební, Katedra městského inženýrství

This article focuses on the issue of creation of operating rules that pertain to the field of operational documentation. Operating rules are an essential part of the efficient operation of the property. This article is targeted to the content site of operating rules by various functional use of objects. A method of operation of the building affects the composition of future operating rules. In this article, the individual include the composition and structure defined according to the method of use of the building.

uhlí
28.4.2014
MUDr. Magdaléna Zimová, CSc., Ing. Anna Cidlinová, MUDr. Jan Melicherčík, CSc., prof. Ing. Zdeňka Wittlingerová, CSc.

Power industry is one of the greatest producers of waste. The character of waste products from the power industry is quite different from waste arising from the other industrial sectors as concerns its composition, methods of removal and possibilities of use. There has been revealed within the solution of the project “The Resort Research Program in the Force of the Ministry of Environment” ref. no. SP2f3/118/08, bearing the name “the research of real properties of waste considered as an acceptable source of non-standard raw-materials (particularly the secondary by-products from the energy generation) in sense of actual legal requirements for the protection of health, environment and the evaluation of the acquired information for the determination of safety processes and requirements for their use”, that products used for the landscaping, in certain events do not fulfill requirements stipulated for the utilization of waste on the ground surface. It means that construction products made from remainders after the coal burning, being sold as safe, can contaminate the environment more than waste used for the same purpose.


zpět na aktuální články
 
 
Reklama