A short circuit is an electrical problem that occurs when 2 electrical wires come into direct contact with each other. This usually happens when the insulation on the wires is damaged. The electrical current then suddenly increases significantly, which can lead to overheating and even fire.
The current takes a shortcut
A little theory: in every electrical installation, there are always at least 2 wires:
- The current enters through one wire.
- It flows out again via the other wire.
In between is an electrical appliance, such as your washing machine, shaver, television, computer, etc., which uses the current to operate.
If the plastic insulation around the wires is damaged, the 2 wires can come into direct contact with each other. The current then no longer flows through the appliance, but takes a shortcut. That is exactly where the name 'short circuit' comes from.
A short circuit means a fire hazard
Normally, an electrical appliance offers resistance to the current. You can compare this to a dam that slows down the water of a river. This keeps the current limited and safe.
In the event of a short circuit, this resistance disappears. It is as if the dam suddenly breaks: the current has free passage and becomes extremely strong. The wires heat up quickly and the insulation material can melt and cause a fire in your home.
How is your installation protected against this?
To protect your home against short circuits, every electrical cable is equipped with an automatic circuit breaker. This automatically cuts off the current as soon as it detects an abnormally high current.
In addition, you also have a main switch (or a residual current device that acts as a main switch), which can switch off the power in your entire home in one movement.
Furthermore, every electrical installation must be equipped with earthing. This allows excess current to flow safely into the ground.
Did you know?
In the past, switches consisted of a wire through which the current flowed. This very fine wire was designed to melt if the current became too strong. This automatically caused a power cut and thus protected the installation.
The word ‘fuse’, from the Latin verb ‘fundere’ (to melt), refers to this mechanism. Nowadays, that technology has been replaced by automatic circuit breakers, which are faster and more reliable.