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SPD Surge Protection Devices

Showing 81–100 of 109 results

Surge Devices 30080 Surge Devices Type 3 8A Single Phase Varistor and EMC/EMI Filter Surge Arrester

Surge Devices Type 3 8A Single Phase Varistor and EMC/EMI Filter Surge Arrester

Delivery usually within 1-3 working days*
SKU: 30080
£133.50
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Surge Devices 30017 Surge Devices Type 3 25A Single Phase Varistor and EMC/EMI Filter Surge Arrester

Surge Devices Type 3 25A Single Phase Varistor and EMC/EMI Filter Surge Arrester

Delivery usually within 1-3 working days*
SKU: 30017
£195.00
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Surge Devices LSPDPV600 SPD Type 1 & 2 600V DC for Solar/PV Installations

SPD Type 1 & 2 600V DC for Solar/PV Installations

1 In stock
More available within 1-3 working days*
SKU: LSPDPV600
£121.77

2-£119.33£2.44£121.77
3-£118.12£3.65£121.77
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Surge Devices LSPDPV1000 SPD Type 1 & 2 1000V DC SPD for Solar/PV Installations

SPD Type 1 & 2 1000V DC SPD for Solar/PV Installations

Delivery usually within 1-3 working days*
SKU: LSPDPV1000
£225.09

2-£220.59£4.50£225.09
3-£218.34£6.75£225.09
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Surge Devices SP30 Surge Devices Pluggable Data Signal Line 30V SPD for 4/20mA Signals

Surge Devices Pluggable Data Signal Line 30V SPD for 4/20mA Signals

Delivery usually within 1-3 working days*
SKU: SP30
£66.42
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Surge Devices SP48 Surge Devices Pluggable Data Signal Line 48V SPD for 4/20mA Signals

Surge Devices Pluggable Data Signal Line 48V SPD for 4/20mA Signals

Delivery usually within 1-3 working days*
SKU: SP48
£66.42
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Surge Devices 610216 Surge Devices 24V DC Cost-Effective Space Saving SPD

Surge Devices 24V DC Cost-Effective Space Saving SPD

Delivery usually within 1-3 working days*
SKU: 610216
£40.59
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Surge Devices D-24/BNC Surge Devices Co-Axial BNC CCTV Arrester

Surge Devices Co-Axial BNC CCTV Arrester

Delivery usually within 1-3 working days*
SKU: D-24/BNC
£66.42
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Surge Devices SY4-POE Surge Devices Type 3 3kA/5kA 1A Cat 6 Power Over Ethernet SPD

Surge Devices Type 3 3kA/5kA 1A Cat 6 Power Over Ethernet SPD

Delivery usually within 1-3 working days*
SKU: SY4-POE
£95.94
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Surge Devices 630043 Surge Devices BS POE 7.5V Power Over Ethernet SPD

Surge Devices BS POE 7.5V Power Over Ethernet SPD

Delivery usually within 1-3 working days*
SKU: 630043
£88.56
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Surge Devices DP1LSA180 Surge Devices Single Telephone Surge Arrester for Installation Into Krone LSA Disconnection Strips

Surge Devices Single Telephone Surge Arrester for Installation Into Krone LSA Disconnection Strips

Delivery usually within 1-3 working days*
SKU: DP1LSA180
£16.24
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Surge Devices DP10LSA180 Surge Devices 10 Pair Telephone Surge Arrester for Installation Into Krone LSA Disconnection Strips

Surge Devices 10 Pair Telephone Surge Arrester for Installation Into Krone LSA Disconnection Strips

Delivery usually within 1-3 working days*
SKU: DP10LSA180
£140.22
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Surge Devices TELCO/EB Surge Devices Earth Bar for DP1LSA180

Surge Devices Earth Bar for DP1LSA180

Delivery usually within 1-3 working days*
SKU: TELCO/EB
£9.59
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WCED Consumer Units

WCED Cable Pack Kit – Forked Terminal Live, Neutral & Earth Cable

5 In stock
More available within 1-3 working days*
SKU: Kit1-CP
£2.00

3-£1.90£0.10£2.00
5-£1.85£0.15£2.00
10-£1.80£0.20£2.00
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Hager VA4T2SDSPD Type 2 Surge Protection Metal Enclosure with 100A Main Switch

Hager VA4T2SDSPD Type 2 Surge Protection Metal Enclosure with 100A Main Switch

Delivery usually within 1-3 working days*
SKU: VA4T2SDSPD
£151.60
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Hager VA4T2SDSPD Type 2 Surge Protection Metal Enclosure c/w Doors and 100A Main Switch

Hager VA4T2SDSPDD Type 2 Surge Protection Metal Enclosure c/w Doors and 100A Main Switch

Delivery usually within 1-3 working days*
SKU: VA4T2SDSPDD
£166.75
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Hager VA2T2SPD Type 2 Surge Protection Enclosure with L&N Cable

Hager VA2T2SPD Type 2 Surge Protection Enclosure with L&N Cable

Delivery usually within 1-3 working days*
SKU: VA2T2SPD
£136.43
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Niglon SP12S-1PN 50kA Type 1+2 Surge Protection Device

Niglon SP12S-1PN 50kA Type 1+2 Surge Protection Device

Delivery usually within 1-3 working days*
SKU: SP12S-1PN
£139.26
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Niglon NSA2-240 Type 2 Surge Protection Kit with Cables

Niglon NSA2-240 Type 2 Surge Protection Kit with Cables

1 In stock
More available within 1-3 working days*
SKU: NSA2-240
£24.04
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Niglon SP12S-3PN 50kA Type 1+2 Surge Protection Device

Niglon SP12S-3PN 50kA Type 1+2 Surge Protection Device

Delivery usually within 1-3 working days*
SKU: SP12S-3PN
£386.68
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More products

Showing 81–100 of 109 results

Surge Protection Devices (SPDs) – Essential Protection for Electrical Systems

A Surge Protection Device (SPD) protects electrical systems from transient overvoltages, commonly known as power surges. These voltage spikes originate from lightning strikes, power grid switching, or internal electrical disturbances. Without protection, surges can damage sensitive equipment, disrupt operations, and lead to costly repairs.

To prevent these issues, SPDs detect excessive voltage and divert it safely to the earthing system, ensuring electrical systems remain stable. BS 7671, the UK wiring regulations, outlines conditions where SPDs may be necessary. Since specific requirements depend on factors like system design and risk assessments, consulting a qualified electrical professional is always recommended.

Types of Surge Protection Devices (SPDs)

SPDs fall into three main categories, each providing different levels of protection:

Type 1 SPD – Main Incoming Protection
  • Installed at the origin of the electrical installation, usually in industrial, commercial, and high-risk environments.
  • Handles direct lightning strikes by discharging high-energy surges safely to earth.
  • Protects buildings with lightning protection systems (LPS) or external surge arresters.
  • BS 7671 recognises Type 1 SPDs for installations that require protection against direct lightning strikes.
  • Common applications: Large commercial buildings, industrial sites, and locations with high lightning exposure.
Type 2 SPD – Secondary Protection for Distribution Boards
  • Positioned at the distribution board to safeguard downstream circuits from switching surges and transient overvoltages.
  • Protects equipment like computers, HVAC systems, and automation controls in commercial, industrial, and residential properties.
  • Limits internally generated surges caused by motors, fluorescent lighting, and circuit breakers.
  • BS 7671 specifies conditions where Type 2 SPDs should be installed, particularly when overvoltages pose risks such as loss of life, public service disruption, or financial loss.
  • Common applications: Office buildings, homes, factories, and retail premises.
Type 3 SPD – Localised Device Protection
  • Installed at the equipment level to provide fine protection for sensitive electronics such as computers, medical equipment, and entertainment systems.
  • Works alongside a Type 2 SPD since it cannot handle large surge currents on its own.
  • Available as plug-in adaptors or DIN rail-mounted solutions, making them ideal for specific appliances.
  • Common applications: Workstations, televisions, routers, and other high-value electronics.
SPDs and BS 7671 Compliance

The UK wiring regulations, BS 7671 (IET Wiring Regulations), outline guidelines for installing SPDs. These regulations assess several factors, including:

  • Exposure to external surge risks, such as lightning strikes.
  • Installation type, focusing on safety-critical applications.
  • Potential damage caused by transient overvoltages, including financial loss and equipment failure.

Although BS 7671 provides essential criteria, a qualified electrician should always evaluate an installation to confirm the appropriate SPD setup.

Which Electrical Systems Require SPDs?

SPDs play a crucial role in protecting electrical systems across various settings, including:

  • Commercial Buildings – Shields office computers, servers, and security systems from power surges.
  • Industrial Sites – Prevents damage to motor-driven equipment, control panels, and production machinery.
  • Residential Properties – Preserves smart home devices, electrical appliances, and heating systems.
  • Data Centres – Ensures continuous operation of servers and networking infrastructure.
  • Healthcare Facilities – Protects medical equipment and emergency systems from electrical disruptions.
  • Renewable Energy Installations – Prevents surge-related failures in solar inverters and wind turbine controllers.
Why Install a Surge Protection Device?
  • Prevents Equipment Damage – Stops power surges from degrading electrical components.
  • Reduces Downtime – Minimises costly repairs and operational disruptions.
  • Ensures BS 7671 Compliance – Meets regulatory requirements in installations where surge protection is necessary.
  • Improves Fire Safety – Lowers the risk of fires caused by overvoltage stress on electrical wiring.

Selecting the Right SPD for Your Installation

Choosing the right SPD depends on system voltage, exposure level, and equipment sensitivity. When selecting an SPD, consider:

  • Nominal Voltage (Uₙ) – Matching the SPD to the system’s operating voltage.
  • Maximum Discharge Current (Imax) – Determining the surge-handling capacity required.
  • Installation Location – Identifying whether protection is needed at the main panel, distribution board, or directly at the equipment level.

For comprehensive protection, combining Type 1, Type 2, and Type 3 SPDs creates a layered defence against surges. Since regulations and requirements vary, a qualified professional should assess each installation to ensure compliance with BS 7671 and site-specific needs.

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