Surge Protection Devices (SPDs)

The Ultimate Protection for Your Electrical Systems

02 August 2023

Welcome to Lewden's dedicated product focus page on Surge Protection Devices (SPDs). As leaders in the electrical industry, we're committed to providing comprehensive insights about SPDs, their functionality, applications, and our top-notch product offerings in accordance with the BS7671:2018+A2:2022 regulation.

What is an SPD?

A Surge Protection Device (SPD) is a critical safety device designed to protect electrical installations and sensitive equipment from the detrimental effects of voltage surges. SPDs form the front line of defense in your electrical system, shielding your devices and installations from the destructive impacts of power surges, which can stem from atmospheric conditions like lightning or alternatively from equipment switching.

How Does a Surge Protector Work?

A surge protector works by rapidly diverting the excess voltage from a surge to the ground, thus preventing it from flowing through the equipment connected to your system. It essentially absorbs and discharges surges that occur in the electrical system. It's important to note that these devices do not influence or interrupt the load current of distribution circuits as they are connected in parallel to the outgoing circuits on the distribution board.

Applications of Surge Protection Devices

SPDs are increasingly becoming a standard requirement in a wide range of facilities due to the critical protection they provide. Some of their major applications include areas housing medical equipment, emergency lighting, fire alarm panels, data centres, power stations, cultural heritage buildings like museums and libraries, commercial establishments, and residential complexes. Essentially, any area where a power surge can lead to serious human injury, significant service interruption, or a large-scale impact on individuals, SPDs are of paramount importance.

The Importance of SPDs

SPDs ensure the continuity of critical operations, preserving human safety and preventing damage to cultural heritage, commercial, industrial, and residential spaces.

Why are Power Surge Protectors Critical?

Electrical surges carry a risk of causing significant disruption, degradation, damage, or even destruction to the connected electrical equipment and wiring. The repercussions of a lightning strike can extend up to 2km away, causing irreparable damage. Implementing robust surge protection measures as mandated by the 18th edition wiring regulations (BS7671:2018+A2:2022) can mitigate these risks, protecting not just your electrical systems but also maintaining business continuity and public safety.

Implementing BS7671:2018 +A2:2022  Regulations

The BS7671: 2018 +A2:2022 regulations necessitate that if the consequence of a surge could result in serious injury to or loss of human life, failure of a safety service, or significant financial or data loss, then protection against surge shall be provided.

In all other cases, protection against surges shall be provided unless the owner of the installation declares it is not required due to any loss or damage being tolerable and they accept the risk of damage to equipment and any consequential loss

Types of Surge Protection Device

At Lewden, we offer a variety of SPDs, each designed to meet specific protection needs.

Type 1 SPDs

These devices are built to protect against the effects of a lightning surge. They are installed at the origin of the electrical installation, guarding against direct lightning currents entering the system from outside the premises.

Type 2 SPDs

Designed for use within sub-distribution boards located downstream of a type 1 device or at the origin of an installation where there's little risk from direct lightning strikes.

Lewden's products feature a standard 5-year warranty period, highlighting our commitment to quality and customer satisfaction. Remember, our surge protection devices aren't just a regulation requirement - they're your first line of defence against the detrimental effects of power surges. Trust Lewden for comprehensive, reliable surge protection solutions.

Note: For detailed information on individual products, please click on the product links.

Why Choose Lewden SPDs?

  • Safety & Compliance: Our SPDs meet all the requirements set by the 18th edition wiring regulations (BS7671:2018+A2:2022). They provide protection where the risk of transient overvoltages could lead to severe consequences.
  • Flexibility: Our SPDs are designed for various applications, including Type 1 and Type 2 surge protections and suitable for single or three-phase applications. They are compatible with both TN (TN-S & TN-C-S) and TT earthing arrangements.
  • Durability: Lewden SPDs are designed to handle a large number of high capacity voltage surges over time, with a typical service life of 5-10 years (depending on the rate and energy content of surges).
  • Guarantee: All Lewden surge protection devices come with a 2-year warranty period as standard.
  • Easy Monitoring: Our SPDs are fitted with an integral-coloured flag or remote signalling contact, which provides an easy indicator of their health or end-of-life status.
Protect your valuable electrical installations today with Lewden's SPDs. Contact our team for more information.
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