What is the purpose of a surge arrester used in a transmission line explain briefly?

A surge arrester is a protective device for limiting voltage on equipment by discharging or bypassing surge current. It prevents continued flow to follow current to ground and it is capable of repeating these functions as specified per ANSI standard C62.

What is a line surge arrester?

Line surge arresters (LSA) are designed to prevent ground faults and short circuits in power lines caused by lightning or switching overvoltages.

How do you protect transmission lines from lightning?

Measures to increase the lightning withstand level of a transmission line and reduce lightning related hazards include: decreasing grounding resistance of towers; adjusting protection angle of the shield wire; using a lightning protection differentiation design for double circuit towers; installing additional lightning …

How does a surge arrester protect equipment from damage caused by a lightning strike?

A surge arrester is a device to protect electrical equipment from over-voltage transients caused by external (lightning) or internal (switching) events. To protect a unit of equipment from transients occurring on an attached conductor, a surge arrester is connected to the conductor just before it enters the equipment.

Where is the surge arrester best installed?

As most surge protectors are installed in parallel to the power panels, normally the best place to install the device is on the main service or panel feeding the facility.

Where are surge arresters used?

These are protective devices used to limit the voltage on apparatus by discharging surge current. The applications of surge arresters mainly include protecting homes to substations. These are mounted on CBs (circuit breakers) in homes, pad-mounted, on pole-mounted transformers and substations.

How does a surge arrester work?

A surge arrester works by diverting the extra voltage into the earth wire, rather than flowing through the electronic devices, while at the same time allowing the normal voltage to continue along its path.

What happens when lightning strikes a transmission line?

When lightning strikes an overhead transmission line, the stroke current is diverted to ground. The current can take three paths. Normally, strokes hit the shield wires placed above the phase conductors, and the current flows to ground through the towers.

What are the effects of lightning on overhead transmission line?

Lightning affects the performance of power lines by both direct and indirect effects where the transient high voltages may cause flashover on the electrical equipment on the power line. Direct lightning strikes, may intercept with line conductors, towers or shielding wires.

Is lightning arrester effective?

It’s important to note that an arrester does not stop lightning, since that would actually be dangerous. It does, in fact, limit and mitigate the electrical charge, but divert is the accurate term, as it sort of gives the lightning a safe route to travel, rather than through your important electrical devices.

How does a surge arrester operate?

Where is surge protection required?

Surge protection (type 1 or type 2) should be fitted at the origin of the supply to the property. This can be installed inside the existing consumer unit, fed from the consumer unit and fitted in its own enclosure, or fed from the supply tails and fitted in its own enclosure.

Why install a surge arrester on a transmission line?

For the past 20 years, surge arrester installation has also become a means to improve the lightning performance of transmission lines. In fact, with arresters, a transmission line can become virtually lightning proof.

Can a line arrester be used to protect equipment?

A line arrester is not generally used to protect equipment. Substation type arresters as well as distribution type arrester can be used for line protection and in this case are then considered line arresters. Transmission Line Arresteris a line arrester applied on a transmission line.

How do you improve the Lightning outage rate of a transmission line?

If you wish to improve the lightning outage rate of a transmission line, there are two ways to do it. The first and most often used is to improve the tower ground resistance. This is done most often since up until 20 years ago, it was the only option.

How does lightning protection work with ohgw lines?

When a line is fitted with arresters on each tower and each phase, the tower ground resistance becomes a non-factor in the system lightning protection, even if the lines are equipped with an OHGW. This is because the arresters do an excellent job of sharing the current of the lightning stroke with nearby towers and other phases.