Energy and Power
Fuses – Principles of design and operation
A fuse consists of a replaceable part (the fuselink) and a fuse holder. Examples of fuse holders are shown in Fig. 1. The simplest fuselink is a length of wire. It is mounted by screw connections in a holder which… Read more
Jul 09, 2011 | By Edvard Csanyi
Energy and Power
Area classification in potentially explosive atmospheres
Area classification defines hazardous areas on the basis of the probability of a flammable atmosphere being present. It is a legal requirement under DSEAR for any employer whose business involves flammable materials in any form, and it results in the… Read more
Jul 08, 2011 | By Edvard Csanyi
Energy and Power
Generator tripping as stability control
Generator tripping is an effective (cost-effective) control especially if hydro units are used. Tripping of fossil units, especially gas- or oil-fired units, may be attractive if tripping to house load is possible and reliable. Gas turbine and combined-cycle plants constitute… Read more
Jul 06, 2011 | By Edvard Csanyi
SCADA
SCADA communication vulnerabilities
Cyber security engineering is expensive. However, the presence of vulnerabilities requires it. In this section we list vulnerabilities we typically see in SCADA systems. The order in the list of vulnerabilities does not reflect a priority in terms of likelihood… Read more
Jul 04, 2011 | By Edvard Csanyi
Electronics
Designing Raw DC Power Supplies
Every type of electrical or electronic apparatus needs a source of electrical energy to function. The source of electrical energy is called the power supply. The two main classifications of power supplies are line-operated power supplies (operated from a standard… Read more
Jul 03, 2011 | By Sa'ad Eddin
Energy Efficiency
Setting circuit breaker tripping with MS Excel spreadsheet
The protective unit of circuit breaker MUST fulfill: Instantaneous trip setting Im < Iscmin for a circuit-breaker Fusion current Ia < Iscmin for a fuse The protective unit (or device) must satisfy the two conditions: Its fault-current breaking rating must… Read more
Jul 02, 2011 | By Edvard Csanyi
Energy and Power
Fuel cells in power section
In 1839, a British Jurist and an amateur physicist named William Grove first discovered the principle of the fuel cell. Grove utilized four large cells, each containing hydrogen and oxygen, to produce electricity and water which was then used to… Read more
Jul 01, 2011 | By Edvard Csanyi
