Power-line Surge voltages and Surge Currents – Causes and Effects
I. Causes Surge voltages and surge currents occurring in low-voltage ac power circuits can be caused by: Lightning surges. Lightning surges are the result of a direct flash to the …
Earth Fault Higher Than Three Phase Fault
In a power system, almost always three phase fault current is higher than the earth-fault current. However, earth fault current near the generator is higher than three phase fault. What …
Selecting 80% or 100%-Rated Molded Case Circuit Breakers According to Philippine Electrical Code
Introduction Molded Case Circuit Breakers (MCCBs) are used as protection devices to ensure safe operation of electrical circuits against overload, short circuit, and ground faults. MCCBs are used in residential …
Modernization of Electrical Substation Automation Systems Using IEC61850
The most important international standard for substation automation systems is IEC 61850 and its related standards. The installation of IEDs in substations, when combined with IEC61850, enables interoperability, flexibility, and …
IEC 61850 Changed Electrical Protection, Control and Monitoring
Intelligent Electronic Devices Electrical protection is as fundamental to the generation, transmission and distribution of electricity as generators, transformers and transmission lines. A couple of decades ago microprocessor based relays …
Electromagnetic Compatibility (EMC) and its Importance in Power Quality
Electromagnetic Compatibility (EMC) refers to the ability of electronic and electrical systems, devices, and equipment to operate in their intended electromagnetic environment without causing or experiencing interference. This interference can …