Low Voltage
How residual current device (RCD) works?
The residual current device (rcd) is used to detect earth fault currents and to interrupt supply if an earth current flows. The main application is to prevent electrocution but RCDs can also be used to protect equipment, especially against fire…. Read more
Jun 11, 2011 | By Edvard Csanyi
High Voltage
MiCOM P139 – Feeder Management and Bay Control
MiCOM P139 is a cost-effective one-box solution for integrated numerical time-overcurrent protection and control. The unit’s protection functions provide selective short-circuit protection, ground fault protection and overload protection in medium- and high voltage systems. The systems can be operated as… Read more
Mar 30, 2011 | By Edvard Csanyi
Protection
History of the development of busbar protection
Up to the mid 1930’s, no widescale efforts had been made to protect busbars on a unit basis. Also there was reluctance in arranging one protective equipment to cause simultaneous tripping of a large number of circuits. Before the British… Read more
Mar 02, 2011 | By Edvard Csanyi
Energy and Power
Protection Relay – ANSI Standards
In the design of electrical power systems, the ANSI Standard Device Numbers denote what features a protective device supports (such as a relay or circuit breaker). These types of devices protect electrical systems and components from damage when an unwanted… Read more
Feb 22, 2011 | By Edvard Csanyi
Protection
Distance Relays
Distance relays respond to the voltage and current, i.e., the impedance, at the relay location. The impedance per mile is fairly constant so these relays respond to the distance between the relay location and the fault location. As the power… Read more
Nov 12, 2010 | By Edvard Csanyi
