How Does An Electrical Transmission System Work?

Dec. 27, 2021

HDPE Pin Type Insulation Device

An overhead line (also known as a transmission line, power line, power cable, and coaxial cable) is a group of suspended cables and wires used to transmit electricity between two or more separate locations so that it can be handled safely and efficiently for consumer use.

How Does An Electrical Transmission System Work?

An overhead wire electrical transmission system allows electricity to be transmitted across the country - creating a seamless, fast supply of electricity across the country. The network is essential to ensure a reliable and regular supply of electricity to our homes, workplaces, and other facilities.

There are two types of overhead lines: transmission lines and distribution lines. Transmission lines carry high voltage 'primary' power between generators and substations, which can then be safely 'stepped down' to a lower voltage level using transformers before being publicly distributed.

Distribution lines are the cables that supply this reduced 'secondary' power to individuals, businesses, and other places of daily use.

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Transmission Line Conductors

Conductors are components attached to transmission lines to promote the passage of electricity from one location to another. They also help to boost the safety of the electrical network.

The four main types of conductors used on overhead lines are AACs (All Aluminium Conductors); AAACs (All Aluminium Alloy Conductors); ACARs (Alloy Reinforced Aluminium Conductors), and ACSRs (Steel Reinforced Aluminium Conductors).

ACSR conductors – and to a lesser degree, AAACs – are the most frequently used conductors on modern transmission lines. As lightweight conductors with high capacitance ACSRs and AACs are also cost-effective – making them ideal for use in high voltage lines requiring multiple or bundled conductors.

Transmission line insulators

Insulators restrict the power flow at defined points in the electrical network. They are used in transmission lines and contribute to the safety and support of the structure by strengthening the line and keeping the conductors separated.

Transmission line insulators can be loosely split into two categories depending on the installation process: pin insulators (installed above the line) and suspension insulators (installed to hang below the line).

For high voltage lines, modular (multiple units) suspension insulators are usually used to handle the higher levels of resistance required. They are made from a series of adjustable insulating discs and can be easily increased or decreased as required.

 Lightning Arrester

Transmission Line Fittings

A variety of hardware accessories are fixed to transmission lines, poles, and towers to assist in the smooth transition of electricity from one place to another. Some of the most common fittings used on transmissions lines and supports include:

Cross arms: A bar attached horizontally to a pole to support its insulators and other hardware;

Guy wires: Strong steel cables that reinforce the structure of a utility pole;

Spacers: Components that keep live conductors on a line a safe distance apart;

Dampers: Devices that protect fragile cables and wires in an outdoor environment;

Earth Wires: Provide a layer of shielding between the line and harsh climatic conditions;

Lightning Arrestors: Safety devices that redirect lightning away from the live line into the ground.

As a composite insulator fittings manufacturer, Taporel Electric produces all kinds of power fittings, including EYE and Clevis, ball and socket, hanging Ring, Y- head, T-head, steel foot, steel cap, flange, and other line accessories. 

We manufacture more than 200 series and 1000 varieties, such as composite insulator fittings, power line fittings, sub-station fittings, power station fittings, and cable accessories, which have been exported to Europe, the United States, and the Middle East for 10 years. Let us help you find the best composite insulator fittings for your project. When you contact us, please provide your detailed requirements. That will help us give you a valid quotation.