Are you looking for power transmission cables for your high-voltage application? HT XLPE cables are the way to go. They provide high efficiency with excellent durability while ensuring safety. This article provides a detailed guide on high-voltage HT XLPE cables and helps you select the right cable for your application.
What are High Voltage HT XLPE cables?
High Voltage HT XLPE cables are insulated cables that are designed to safely carry high-voltage electrical current over long distances. They are often used in transmission lines, substations and other electrical infrastructure.
Materials Used to Manufacture High Voltage HT XLPE Cables
High Voltage HT XLPE Cables are composed of the inner conductive core with an insulating layer, followed by an inner sheath, armour and outer sheathing.
The conductor is made of either copper or aluminium, covered by an insulating layer.
The most distinctive component of XLPE cables is the insulating layer, which is typically made of cross-linked polyethene (XLPE). This XLPE insulation is strong and resistant to wear and tear, making it ideal for long-term use. Apart from that, it is also resistant to most chemicals, allowing it to be used in applications where other materials would be prone to damage.
The XLPE layer is covered by the inner sheathing, generally made of PVC. This sheathing is then followed by metal armour which provides strength and durability to the cable.
The outer jacket is available in a variety of materials, including PVC, rubber and EPDM. The jacket also shields the cable from env ironmental elements like moisture, extreme temperatures and UV radiation.
Things to consider when buying HT XLPE cables
To ensure efficient transmission of the intended power while maintaining the safety of the cable, it is important to consider your requirements. It is critical to select the best-suited HT XLPE cable based on the size of the conductor, voltage grade, number of cores and type of conductor of the cable.
Size of the conductor
The size of the conductor of a High Voltage HT XLPE cable determines the amount of current it can carry. The larger the size of the conductor, the more current it can safely handle.
Generally, a 12-22kV 95 sq. mm. single-core copper conductor XLPE cable has a current carrying capacity of around 230 to 345 amps. Compared to that, a 1000 sq. mm. single-core copper conductor XLPE cable has a current carrying capacity of around 660 to 1240 amps.
Voltage grade of the cable
The voltage grade of a High Voltage HT XLPE cable indicates the maximum working voltage that the cable can sustain without breaking down. To ensure safe operation, it is advised to select a cable with a voltage grade higher than the expected operating voltage. High Voltage HT XLPE cables are available in a range of voltage grades, from 6kV to 33kV, and some special grades can even go as high as 66kV.
Number of cores in the cable
The number of cores in a High Voltage HT XLPE Cable refers to the number of individual conductors in the cable. Single-core cables are typically used for short-distance, low-voltage applications such as between a transformer and a switchboard, whereas three-core and four-core cables are typically used for longer-distance, higher-voltage applications such as between two substations.
Type of conductor
There are two types of conductors available in HT XLPE cables: Copper conductor and aluminium conductor.
Copper has a high electrical and thermal conductivity, which makes it very efficient for transmitting electricity while minimising the risk of overheating. Furthermore, corrosion resistant property of copper makes it a great choice for long-term use in harsh environments.
On the other hand, aluminium is cost-effective, making it a great option for budget-conscious projects. However, aluminium is comparatively less efficient and is more prone to oxidation and corrosion than copper. As a result, it is not suitable for applications where efficient transmission of power and corrosion resistance are of utmost importance.
Benefits of using high voltage XLPE cables over PVC cables
The difference between an XLPE cable and a PVC cable lies in the insulating material used to cover the conductors of each core of the cable. However, this simple difference provides various advantages to XLPE cables over PVC cables.
The use of XLPE offers improved electrical performance, greater flexibility and enhanced safety. The improved electrical performance of HT XLPE cables allows for more efficient energy transfer.
Additionally, their low capacitance and inductance values result in minimal voltage drop and impedance, allowing them to deliver power with fewer energy losses. As a result, XLPE cables offer around 25-30% higher current carrying capacity than PVC cables.
Finally, XLPE is comparatively more durable than PVC, thereby providing better strength to the cable with an operating temperature range of around 90℃ to -90℃.
Raise Quotation for HT XLPE Cables online at L&T-SuFin
High Voltage HT XLPE Cables are highly recommended for applications where high voltage current is to be transmitted over a long distance with minimal energy loss. However, you need to analyse your requirement and select the best-suited cable to minimise cost while ensuring safety. L&T-SuFin offers a wide range of HT XLPE Cables to choose from for all your applications. Their affordable prices and excellent logistic support make them the leading marketplace in the domain.