Q1 stops conducting as its base voltage is 0V now and it is no longer biased. Now the switch is closed i.e The circuit is ‘shorted’, the output voltage drops to 0V as there exists no potential difference. As long as the green light is on, there is no short circuit. During this time Red LED D2 remains off as there is no flow of current through it. The current flows through the green LED D1 and it turns ON. When the power supply is ON, transistors Q1 and Q2 get biased and start conducting. The circuit is shorted when the switch is closed.Ĭurrent chooses the path that offers the least resistance. A switch is used to replicate the shorting of the circuit. LEDs are connected in order to identify the flow of current and the presence of a short circuit. The circuit is powered by a 5V DC supply. The circuit discussed here uses two simple transistors to protect the circuitry from short circuit. A short circuit protection circuit can be built using relays, transistors and even basic diodes. There are many ways to override the short circuit. The short circuit protection circuit discussed below plays the same role of a fuse in the household electric circuits. Hence, using circuits that protect the circuit from short circuiting are important. A short circuit can cause significant damage to the components such as ICs, rendering them useless. We might make wrong connections or connect the wrong terminals i.e., anything can go wrong. Similarly, while working with smaller circuits, we are always at the risk of a short circuit. A fuse is used to stop the surplus current.
A surplus of current then flows through the appliances and can damage all the other household appliances if not stopped. We often encounter short circuits in our daily life too! Electrical appliances stop working after a sudden spark sometimes, this is due to short circuits in their internal circuitry. Short circuits are common while working with electricity. The IC would be damaged due to the excess current that would pass through it. Imagine if there was an expensive IC connected to the nodes where the short circuit occurred. Hence, the total current present in the circuit goes through the short. If the resistor R2 is shorted by some problem, the current chooses to go through the least resistance path i.e., the short. Hence the current that flows through is the same and is equal to half of the total current in the circuit. The above figure shows the flow of current through the short circuit in a practical case.Ī battery of 5V is connected in parallel with the two resistors of equal resistance. Ideally, an infinite amount of current passes through the short circuit.