Short Circuits: Why Do They Happen?
A short circuit can be the reason why an electronic device is not functioning properly. It occurs when electrons take an unintended path. Connecting the negative and positive terminals of a battery will cause a short circuit. Here's a deeper look at what short circuits are:
Reasons for Short Circuits The primary cause of a short circuit is when two components of a device are improperly connected. A resistor, for example, can become imbalanced if one side should be connected to a positive rather than a negative energy source.
Many times, bad connections result from careless soldering work, in which a piece of solder drips on the circuit board. Another common reason for a short circuit is when a piece of metal falls onto the circuit board, such as after cutting the legs of a resistor. It can be difficult to remove the metal, which can cause multiple shorts, if it falls underneath the board. Short circuits can also be caused by damaged components, such as pins on a transistor.
The most dangerous type of short is when bare wire is exposed to other bare wire due to worn insulation. This type of connection can cause electric shock and even a spark that could start a fire. When electrons take a shorter path, it reduces resistance, which increases heat. The more wire or metal heats, the greater the potential for burns and fires. Short circuits may also result from loose connections that allow neutral live wires to cross. Sometimes wire can be exposed due to rodents chewing on cords.
How to Detect a Short Circuit The obvious signs of a short are when you see sparks, flames or smoke after flipping a switch. Since a short causes a circuit breaker to trip, the remedy is to flip the breaker in the opposite direction.
An effective way to identify a short circuit is to use a multimeter with a continuity checker. This device beeps when it detects a connection between its two measurement probes. Using the probes, you merely touch the places you want to test for connections and listen for beeps.
