Underground cables are electrical cables that are buried underground for power transmission and distribution, telecommunications, or data transmission. These cables are protected from physical damage and environmental factors such as water, heat, and cold.
There are several types of underground cable, including:
- Copper cables: these are the most common type of underground cables and are used for electrical power transmission and distribution.
- Aluminum cables: these are similar to copper cables but are less expensive and have a slightly lower conductivity.
- Fiber optic cables: these are used for telecommunications and data transmission. They are made of glass or plastic fibers that transmit light signals.
- High-voltage cables: these are used to transmit high-voltage electricity over long distances and are typically made of aluminum or copper.
- XLPE cables: these are made of cross-linked polyethylene and are used for high-voltage power transmission. They are known for their durability and resistance to chemicals and abrasion.
- PVC cables: these are made of Polyvinyl Chloride and are used for low voltage power distribution and control circuits.
There are several ways to lay cable in the underground, including:
- Direct burial: this method involves burying the cable directly in the ground without any additional protection. This method is typically used for copper and aluminum cables.
- Ducts: this method involves placing the cable in a protective duct or conduit before burying it in the ground. This method is used for both power and telecommunications cables.
- Trenching: this method involves digging a trench in the ground and laying the cable in the trench before covering it back up. This method is used for both power and telecommunications cables.
- Plowing: this method involves using a plow to bury the cable in the ground. This method is often used for fiber optic cables, as it allows for precise depth control and minimal damage to the cable.
- Horizontal directional drilling (HDD): This method involves drilling a hole underground, and pulling the cable through the hole. This method is often used where trenching or plowing is not feasible, such as under a river or a road.
- Aerial: This method involves laying the overhead cable, on poles. This method is used for power distribution and telecommunications.