Underground cable facts for kids

An underground cable is like a hidden pathway for electricity or internet signals. Instead of being high up in the air on poles, these special cables are buried deep below the ground. They help deliver power to homes and businesses, and also carry communication signals for phones and the internet.

Safety sign to indicate a 20 kV underground cable

What Are Underground Cables?

Underground cables are a different way to move electricity and information compared to overhead cables. Overhead cables are the ones you see hanging on tall poles above the ground. In many city areas, especially where there are lots of tall buildings, you won't see many cables in the air. This is because underground cables look much nicer – they're out of sight! They are also safer because people can't accidentally touch them.

Why Do We Use Them?

There are several reasons why cities and towns choose to use underground cables:

• Looks Better: They don't block views or make the sky look messy. This is especially important in beautiful city centers.
• Safer: Since they are buried, there's less risk of people or animals touching live wires. They are also protected from storms, strong winds, and falling trees.
• More Reliable: Because they are underground, they are less likely to be damaged by bad weather like ice storms or lightning. This means fewer power outages.
• Last Longer: Even though they cost more to put in at first, underground cables often last for a very long time.

How Are They Installed?

Putting underground cables into the ground is a big job. Workers have to dig trenches, which are long, narrow ditches. The cables are then carefully placed inside these trenches. Sometimes, they use special machines to bore tunnels underground without digging up the whole street. After the cables are laid, the trenches are filled back up, and the ground is restored.

Marking Underground Cables

It's very important to know where underground cables are buried. This is because digging into them by accident can be very dangerous. To help with this, special markers are often placed on the surface at regular spots. These markers warn people about the cables below and show their path. This helps construction workers and others avoid hitting the cables when they are digging.

Images for kids

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  An underground cable marker. Markers are put at regular intervals to show the route and warn of the hazard of digging into the cable.

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  A former pylon transformer south of Markgröningen, Germany. Today, the pylon carries only a switch fed by two underground cables.

See also

In Spanish: Línea eléctrica subterránea para niños