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Surge, lightning and device (Type 1,2 & 3) protection for building installations

To operate a building and the electrical devices within it according to safety standards, effective lightening and surge voltage protection is indispensable. To ensure you choose the correct devices, quality, capacity and longevity are particularly important – only if these are granted will downtime and repairs be prevented in the long run. The ‘Safe Energy Control’ product range from Phoenix Contact takes lightning and surge voltage protection to a new level with its redesigned spark gap technology.

Suitable points of installation

To implement an effective surge protection concept for buildings, the endangered power lines must first be identified. The necessary protective devices can only be installed after identifying the lines that carry power into or out of the building to be protected. The necessary protective devices are deployed in steps – the most powerful protective device is installed directly at the building entry, and the one with the fastest response characteristic is installed directly before the end device to be protected.

Optimal protection at the building entry (Type 1 – Lightning)

Just as important as in industrial environments is the protection of the main and sub-distribution boards in single-purpose buildings and private housing. The best point to protect the building and the electronic devices within it is directly where the main power enters the building. If there are no protective devices that are sufficiently powerful at this point, there can be no effective protection concept. The most important question in this context that arises during planning is whether or not the building has external lightning protection.

Buildings with external lightning protection can experience immense lightning energy in the event of a direct lightning strike. In this case, VDE regulations require a Type 1 lightning current arrester. Spark gap technology has established itself as the most efficient solution for this type of lightning current arrester. The Type 1 arrester from the SEC (Safe Energy Control) product range is equipped with a novelty: Spark gap technology that is free of secondary power supply currents (see note 1 below). The improved system protection that results from this increases system availability and reduces downtime (see note 2 below). The Type 1 arresters from the SEC range can also be operated in systems that are protected up to 315A with a single-branch configuration without any backup fuse of their own. If systems with larger rated currents are forced to dispense with the arrester backup fuse due to a lack of space, the Type 1 arrester provides an interesting solution. The new FLT-SEC-Hybrid protective device is the first pluggable combination of Type 1 lightning current arrester and built-in backup fuse.

Protection of the main and sub-distribution boards (Type 2 – Surge)

For buildings without external lighting protection systems and low lightning risk, Type 2 surge voltage protectors at building entry are sufficient. In any case, however, these protective devices are also used downstream from Type 1 for additional system protection in sub-distribution. This way, coupled surge voltages are safely reduced to levels acceptable for downstream systems.

The new Type 2 arrester from Phoenix Contact’s SEC range has been given two special functions. On one hand, the Valvetrab SEC arrester is the world’s narrowest surge voltage protector on the market. On the other, the device can also be operated in systems that are protected up to 315A with a single-branch configuration without any backup fuse of their own. This not only saves space but also plenty of time and money during installation. A further advantage of this design is a significantly higher protection level due to the shortened cable distances.

Protection of end devices (Type 3 – Device)

The last stage of protection in an all-encompassing protection concept is where Type 3 surge voltage protectors come to the fore. These protective devices, also referred to as ‘fine protection,’ are used directly before the end devices to be protected, shielding them from coupled peak voltages in the cables. The Type 3 arresters from the SEC range are available for all common rated voltages and can also be used without in many systems without backup fuses. The redesigned internal disconnect device for the arrester allows installation in both AC and DC systems. This significantly expands its potential areas of deployment.


The correct choice of lightning current and surge voltage protector is the first step for effective building grid protection. Only an all-encompassing protection concept can mitigate the consequences of surge voltages in buildings over the long term. The new SEC product range from Phoenix Contact greatly simplifies both the choice and installation of a suitable protective device. Optimally harmonised protective devises ensure the safe interaction of the individual arrester types. The redesigned spark gap, which is free of secondary power supply currents, as well as the ability to do without a backup fuse for any type of application or arrester, both take surge protection to a new level. If the status display of an arrester from the SEC range indicates that replacement is necessary, an additional advantage is available to the customer: Phoenix Contact will replace the plugs free of charge for up to five years after purchase.


  1. SEC –Safe Energy Control: The new Safe Energy Control (SEC) product range stands for long service life and high performance for lightning and surge voltage protection – these arresters provide very reliable protection. The redesigned spark gap in combination with Type 2 and Type 3 arresters offers indispensable protection concept for power supplies. The SEC components’ uniform, compact design and universal pluggability are satisfying the growing customer demand for an easy-to-install full-scale package.
  2. Power supply secondary current: Power supply secondary current is the portion of the current flow that, following the discharge of surge voltage, flows from the power grid through the spark gap. This secondary current can last for several milliseconds at the intensity of a short circuit current. This makes secondary currents a load on the entire system, and they may well cause voltage drops and associated malfunctions. Moreover, they may trigger an upstream device for overload protection.

For further information on lightning, surge and device protection please contact us. Additional information can also be obtained on Safety Energy Control technology from the download below.


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