Deepakkumar Yadav
What are the reasons for electric shocks? The human failure in handling the electrical components or repairing the distribution system without switching off the supply, the ultimate effect of electric shock on human body may be death. Electric shock on human body may be fatal but it may be due to Electric shock may result … Read more
There are three basic pathways electric current travels through the body 1) Touch Potential (hand/hand path) 2) Step Potential (foot/foot path) 3) Touch/Step Potential (hand/foot path) Figure illustrates these groups and the path of current through the body. 1) Touch Potential (hand/hand path) In a touch potential contact, current travels from one hand through the … Read more
Difference between MCB and RCCB, MCB vs RCCB What is Full Form of MCB Miniature Circuit Breaker What is Full Form of RCCB Residual Current Circuit Breaker 1. Protection MCB provide protection of Overload and Short Circuit RCCB provide protection of Earth leakage protection 2. Pole Available in MCB and RCCB in MCB Single pole … Read more
Voltage or Potential Transformer Q. State the specifications of PT as a protective transformer. Voltage transformers (potential transformers) are used for measurement and protection. They may be either single phase or three phase units. Voltage transformers are necessary for voltage, directional, distance protection. Primary of voltage transformer is connected to power circuit between phase and … Read more
Burden on CT Q. Define CT burden Impedance of secondary circuit is expressed in ohms and power factor. It can be expressed as apparent power and rated secondary current at specified power factor. This power factor is not the power factor of the secondary load. The circuit connected the secondary winding is termed as burden … Read more
Practical Considerations in using Gases for Insulation Purpose Air has great advantage of being low in cost, therefore it found some application at increased pressure in condensers, cables and other insulation constructions. But it does not satisfy the second requirement, since ionization of air is accompanied by emission of ozone, nitrous and nitric oxides causing … Read more
Gases as Insulating Medium Gases used as insulation must satisfy the following basic requirements Gas must be chemically inert and should not react with dielectrics, in combination with which it is used, and with other materials used in the construction of the apparatus. During the ionization of the gas, which to a certain degree is … Read more
Control of Over Voltages due to Switching and Power Frequency (a) Energization of TL in or more steps by inserting resistances and withdrawing them afterwards It is normal practice to have a series resistance with the circuit breaker contacts during switching ON and then but short circuiting this resistance after a few cycles. (b) Eliminating … Read more
Distribution of Switching Surges (EHV and UHV Systems) Switching surges originate when there is sudden release of internal energy stored in the electrostatic form (in the capacitance) or in the electromagnetic form (in the inductance). This can happen in following situations : (i) Current chopping phenomenon : Interruption of magnetizing currents (transformers/reactors re switched … Read more
Switching Surges due to External and Internal factors The above all were the protection systems against the direct lightning strokes which is purely natural and we are not having any control over it. Switching surges are the over-voltage stresses applied on the traction system, and are generally transient in nature. The surge voltage is defined … Read more