Please use another Browser

It looks like you are using a browser that is not fully supported. Please note that there might be constraints on site display and usability. For the best experience we suggest that you download the newest version of a supported browser:

Internet Explorer, Chrome Browser, Firefox Browser, Safari Browser

Continue with the current browser

Line surge arresters


We supply non-gapped and externally gapped line surge arresters for overhead lines for up to 800 kV. Line surge arresters offer the most economical and effective lightning protection on new and existing overhead line systems. Special areas of application include e.g. areas with high lightning frequency, poor soil or tower grounding resistance (e.g. for sandy or rocky ground), unprotected overhead lines (without ground wire), reducing switching impulse current overvoltages in high-voltage systems, and providing extended station protection.

Do you have any questions? Are you looking for more information about our line surge arresters? We have experts to assist you with any issue.
Contact the customer service

Product overview

Overview of our line surge arresters

We offer line surge arresters for system voltages of 12 kV to 800 kV. Siemens line surge arresters can be directly installed without an external spark gap (NGLA, non-gapped line arrester) or with an external spark gap (EGLA, externally gapped line arrester).

Our product families


Non-gapped line arresters (NGLA) – line surge arresters without spark gap

Non-gapped line surge arresters (NGLA) offer a high degree of mounting flexibility and operational reliability. Depending on the tower design and the arrangement of insulators and lines, these arresters can either be installed directly on the insulators or on the tower.

Thanks to their high energy absorption capacity, non-gapped line arresters offer a very high level of protection against overvoltages caused by lightning and network-generated switching impulse current overvoltages.

To galvanically isolate the line surge arrester from the line voltage in the unlikely event of a fault or thermal overload, a disconnector is installed in series. It automatically and immediately disconnects the line surge arrester from the line voltage. This allows the affected overhead line to continue to be used until replacement can be scheduled.

In addition to the line surge arresters, the new ACM advanced monitoring system can be installed to provide arrester condition monitoring. This system monitors wirelessly and provides detailed information about leakage currents and converted energy.


Technische Daten


Externally gapped line arresters (EGLA)– line surge arresters with external spark gap

EGLA line surge arresters have an external spark gap placed in series that galvanically isolates the active part of the arrester from the line voltage in normal conditions. In case of lightning, the spark gap is ignited and the overvoltage is safely discharged to the ground. EGLA line surge arresters prevent all insulator flashovers caused by lightning strikes. As such, EGLA increases network stability as well as the availability of the overhead line.

An additional benefit of EGLA line surge arresters is that there is no leakage current, because the series gap disconnects the active part of the EGLA from the system voltage.

This compact design is often the only option to install line surge protectors on existing towers with very small clearances.

Siemens EGLA line surge arresters are available for system voltages of up to 550 kV.

All Siemens EGLAs are designed and tested to comply with the latest IEC 60099-8 standard, which became effective in January 2011.


Software analysis for customer-specific applications

Siemens optionally offers software analysis (simulation) based on Cigré studies to examine and conduct preliminary tests of customer-specific applications as a way of determining the optimal, cost-effective solution. With this approach, the customer only needs to equip particular phases or individual line segments with line surge arresters, and can still ensure sufficient lightning protection of the overhead line.