Power System Overvoltages and Insulation Coordination – Part 1
Note: This is the first part of power system voltages and insulation coordination. Insulation coordination is dealt with for three phase AC systems with nominal voltages Un > 1kV in …
The Effect of Earthing Methods
Earthing the System Neutral Most earthed systems employ some method of earthing the system neutral at one or more points. Effectively Earthed System A system is effectively earthed when the …
Normative and Informative Annexes Compliance
The terms ‘normative’ and ‘informative’ are commonly used in IEC and other derivative standards to define applications of annexes. A normative annex is an integral part of a Standard which …
Sub-synchronous torsional interaction (SSTI)
Definition Sub-synchronous torsional interaction (SSTI) is a phenomenon in power systems where mechanical torsional oscillations of a turbine-generator shaft interact with the electrical sub-synchronous frequency components of the power system. …
Voltage and Frequency Limits of Electric Motors – IEC 60034-1
Electric motors rated for use on a fixed frequency power supply, combinations of voltage variation and frequency variation are classified as being either zone A or zone B, in accordance …
Earth Leakage Circuit Breaker and Residual Current Circuit Breaker – Application, Operation and Limitations
International Standards Protection of human life, Equipment against earth leakage is an important aspect which needs to be taken into consideration. There are different international standards which are clearly defining …