9 feb. 2008

INSTALATII ELECTRICE INDUSTRIALE



Lucrarea de fata prezinta o parte din problemele instalatiilor electrice, adresandu-se celor care practica meseria de electrician. La baza ei sta o bogata literatura de specialitate cat si o experienta profesionala de peste douazeci de ani a autorului.




Structura cartii:

Capitolul 1. Componentele instalatiei electrice, documentatiile tehnico - economice corespunzatoare cat si problematica autorizari electricienilor conform regulamentelor in vigoare.
Capitolul 2. Elementele de baza teoretice din electrotehnica: electrostatica, electrocinetica,
electromagnetismul si curentul alternativ.
Capitolul 3. Caracteristicile principale ale materialelor conductoare si izolatoare cel mai des
folosite insistand asupra conditiilor care sunt impuse de normativele in vigoare la
folosirea acestora in instalatiile electrice.
Capitolul 4. Notiuni de tehnica iluminatului, realizarea instalatiilor de iluminat si dimensionarea coloanelor si circuitelor de iluminat.
Capitolul 5. Instalatiile interioare de forta; dimensionare, verificare si protectie. Am inclus tot
in acest capitol si o mica prezentare a motoarelor electrice deoarece finalitatea
acestor instalatii este alimentarea si comanda actionarilor cu motoare electrice.
De asemenea am considerat necesar ca acest capitol sa contina si date
despre instalatiile de forta prefabricate (bare capsulate) si liniile de contact.
Capitolul 6. Compensarea energiei reactive, dimensionarea si realizarea instalatiei de
compensare.
Capitolul 7. Instalatiile de legare la pamant .
Capitolul 8. Instalatiile de protectie contra traznetului. Dupa notiunile teoretice sunt
prezentate cateva instalatii de paratraznet.
Capitolul 9. Utilizarea microprocesoarelor la comanda actionarilor electrice. Sunt prezentate
notiunile de baza si exemple de aplicatii de actionari electrice comandate de
microprocesor (pornirea si reglarea vitezei motoarelor asincrone).
Capitolul 10. Mutatoare: Redresoare, convertoare de frecventa, variatoare de c.c., etc. Teorie
si aplicatii.
Capitolul 11. Acumulatoarele electrice. Scheme uzuale si aplicatii. Redresoare pentru
incarcarea acumulatoarelor.
Capitolul 12. Masurarile, verificarile si incercarile instalatiilor electrice. Este un capitol
important deoarece orice instalatie electrica trebuie sa respecte si sa satisfaca
normativele si normele in vigoare.
Capitolul 13. Normele de protectia muncii specifice
Capitolul 14. Lista normelor, normativelor si legilor in vigoare care trateaza instalatiile
electrice.
Capitolul 15. Anexe. Se prezinta date generale, simboluri, constante cel mai des folosite in
electrotehnica.









Automation and control of pumps located at a large distance from the water tank

Automation and control of pumps located at a large distance from the water tank

Author: Sorin MORANCEA, Melior Electroinstal SRL Hunedoara, moranceas@yahoo.com


A water supplying system is generally consisting in a collector (located near user) and one or more pumps located near the water source (wells, lakes, etc.). Water is being pumped by these pumps through the piping system and sent towards the collector. Most of the times, pumps are located at an adequate distance which doesn?€™t allow to be connected with a control cable to the collector. This fact makes impossible their control by traditional method. And thus the necessity of pumps being controlled by radio waves or more recently, by GSM, had arisen.
The level sensor is calculating the level from the collector and transmits it through the control cables to the control box. Here, the signal is being transmitted by GSM to the control board, activating the pump. This control board includes the safety equipment, climate-proof equipment, as well as the control equipment for starting pumps functioning. The communication equipment makes possible for the control board and the supplying board necessary for the functioning of the pump to stay in touch permanently. The scheme was conceived in such a way as to allow some manual, local or remote controls.
The GSM communication system is made by Siemens and consists of: communication modem, adjustable automat, the energy supply source and the magnetic aerial. This communication system is functioning by GPRS method. This system of transferring data files (GPRS) is a relatively new method added to GSM service which allow for the information being transmitted and received through a mobile-phone network. The maximum speed up to 171.2kbps are obtained using 8 access ways in the same time, thing which makes GPRS being three times higher than the transmission speed through nowadays communication networks and ten times higher than the rapid data transfer (CDS) through GSM networks. Speed is one of the main advantages of the GPRS as compared to CDS. High speed and instant connection is a very important feature for crucial applications.
Some economical calculations can be made in order to check the amount of energy saved through this automation.