What happens when a short circuit occurs in an electric circuit?

Question

Why can a short circuit be dangerous?

Answer 1

A short circuit occurs when the intended path of electrical current is short cut, bypassed, or jumped along its intended route.
When a short occurs when, for one reason or another, the electricity will essentially jump to a part of the circuit it is not supposed to and possibly cause damage.

For instance, electricity in a desk lamp, is supposed to go from one prong in the outlet, through the cord, into the lamp, into the bulb, and then return back out the cord and into the other prong of the wall outlet.
If you were to stab the cord with a ford, puncturing the insulation in the wire, the whole process would be bypassed and the current would go through the path of least resistance (fork). If you were holding the fork, the moisture of your hands would allow you to contact the electricity and your body (mostly water) would pass that current to your heart and most likely kill you.
A similar thing occurs with putting a knife in a toaster or dropping a running hair dryer in a bathtub...The current is meant to travel through the heating elements but when water touches it, the current's resistance is reduced significantly allowing the electricity to travel elsewhere.

Sometimes shorts are caused by arcing. An arc would be where the electricity jumps from one wire to another because of moisture in the air, electrical interference, sudden increase in current, or some other factor. This short is dangerous because it happens unknowingly by instelf and that will cause harm to persons nearby or start fires.

Answer 2

When a short occurs, you are eliminating any intended load on the circuit, and the current created because there is no load can become excessive.

In your house a normal circuit breaker is 15 Amps. When a short occurs, the current exceeds more then 15 Amps, and the circuit breaker will trip (open) a short time later. There is some latency so that you can have momentary overloads.

The Problem is the current and the Resistance of the wire can create heat. If the short lasts too long, the heat may melt the insulation of the wire and then cause a fire. Under a short, you may see the wire glowing red, because it is very hot.

Answer 3

A short circuit is a bypassing of the regular ciruit with no resistance ... as if you "short" the terminals in a battery.

Any power source has an internal resistance, and if you
remove the external resistance ... the circuit, light, applicance,
TV, radio, whatever, and substitute a wire with no resistance
a huge current can flow in unexpected locations, like through
the wiring in your house or in your body ... if you are the object
to short the circuit. House circuits have circuit breakers designed
to prevent dangerous currents from flowing in the wires and
causing them to melt.

If you have a circuit driven by a battery, the battery can
overheat or explode. If you have a tool in your hand it can
carry so much current that it will glow and can melt.

Answer 4

Hopefully, the fuse blows or the circuit breaker trips.
A short circuit allows a great amount of electricity (current) to flow through wires and circuits that were not designed for such loads.

They are dangerous from both an electrocution or electrical shock potential to the fire hazard they may present.

Answer 5

Due to Vibration , cause loose connection - make overheating- make Insulation failure- make short circuit- burning- All happening Due to lack of Maintenance.Poor Maintenance,poor supervision,poor Inspection & rechecks, poor quality control & Poor Quality Assurance control.