Short Circuit Current Calculation | Transformer to LV Panel, SMDB & DB Explained

Hello everyone and welcome back to my channel Rashi Pal. In today's video, we are going to learn one of the most important topic in electrical design that is short circuit current calculation. We will start from the basic concept understand what shortcircuit current actually means and then go step by step through a real

calculation example. By the end of this video you will able to calculate fault current at any point in the electrical system like a transformer panel or load end. So the question arises here what is short circuit current actually? So whenever two points in an electrical circuit that are normally at different voltage comes in contact with each other

like uh a face to face or we can say phase to neutral or face to earth then short circuit happens. During this condition the current bypasses the normal load and flow through a very low resistance path. Because the resistance is very small, the current suddenly increase to a very high value. This high current is called

short circuit current or we can say fault current. It can be 10 to 20 times greater than the normal current and can cause serious damage to cable circuit breaker and equipment if not properly controlled. That's why before designing any electrical system we must calculate short circuit current at every point so that we can select safe and suitable

protection device. So now next question arises why do we need to calculate short circuit current? Actually short circuit current calculation help us to select circuit breaker with proper braking capacity and uh verify bus bar and cable with with stand capacity. So always ensure overall safety and reliability of the system. Now let's take an practical