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SPD Surge Protection Devices

Safeguard your electrical systems with our SPD Surge Protection Devices. Engineered to protect against voltage spikes and electrical surges, these devices enhance the safety and longevity of your equipment. Suitable for residential and commercial use. Shop now for dependable surge protection.

Showing 1–20 of 110 results

WCED WEC440SP Meter Supply Isolator with Surge Protection WCED WEC440SP Meter Supply Isolator with Surge Protection

WCED WEC440SP Meter Supply Isolator with Surge Protection

89 In stock
More available within 1-3 working days*
SKU: WEC440SP
£29.99

34£28.49£1.50£29.99
59£26.99£3.00£29.99
1019£25.49£4.50£29.99
2099£24.74£5.25£29.99
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WCED WME440SP Metal Meter Supply Isolator with Surge Protection

Metal Meter Supply Isolator with Surge Protection

1 In stock
More available within 1-3 working days*
SKU: WME440SP
£35.45

3-£33.68£1.77£35.45
5-£32.79£2.66£35.45
10-£31.91£3.55£35.45
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WCED WME3P40SP WCED Type 2 20kA/40kA 3P+N Surge Arrestor with Metal Enclosure 1

WCED Type 2 20kA/40kA 3P+N Surge Arrestor with Metal Enclosure

Delivery usually within 1-3 working days*
SKU: WME3P40SP
£34.49

3-£32.77£1.72£34.49
5-£31.90£2.59£34.49
10-£31.04£3.45£34.49
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FuseBox SPDCUKITT2 FuseBox SPDCUKITT2 Type 2 Surge Protection Device Kit 1

FuseBox SPDCUKITT2 Type 2 Surge Protection Device Kit

10 In stock
More available within 1-3 working days*
SKU: SPDCUKITT2
£25.50
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WCED WSPD240KIT2 Type 2 40kA Surge Arrestor SPD Kit with Busbar and Earth Link 1

Type 2 40kA Surge Arrestor SPD Kit with Busbar and Earth Link

14 In stock
More available within 1-3 working days*
SKU: WSPD240KIT2
£16.95

3-£16.10£0.85£16.95
5-£15.68£1.27£16.95
10-£15.26£1.70£16.95
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WCED WSPD440 WCED Type 2 20kA/40kA 3P+N Surge Arrestor 1WCED WSPD440 WCED Type 2 20kA/40kA 3P+N Surge Arrestor 2

WCED Type 2 20kA/40kA 3P+N Surge Arrestor

Delivery usually within 1-3 working days*
SKU: WSPD440
£25.50

3-£24.23£1.28£25.50
5-£23.59£1.91£25.50
10-£22.95£2.55£25.50
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hager-vme02spd-surge-protection-kit

Hager VME02SPD Type 2 Surge Protection Kit

Delivery usually within 1-3 working days*
SKU: VME02SPD
£34.86
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WCED WMCUSP440C 3 Phase SPD with 40A Curve C 4 Pole MCB

WCED WMCUSP440C 3 Phase SPD with 40A Curve C 4 Pole MCB

Delivery usually within 1-3 working days*
SKU: WMCUSP440C
£59.90

3-£56.91£3.00£59.90
5-£55.41£4.49£59.90
10-£53.91£5.99£59.90
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WSPD240KIT1 2 Pole Double Module Type SPD with Cable Links

WSPD240KIT1 2 Pole Double Module Type SPD with Cable Links

1 In stock
More available within 1-3 working days*
SKU: WSPD240KIT1
£16.95

3-£16.10£0.85£16.95
5-£15.68£1.27£16.95
10-£15.26£1.70£16.95
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WCED WSPDT2-CB 1 module 40kA 2 Pole SPD Kit

WCED WSPDT2-CB 1 module 40kA 2 Pole SPD Kit

6 In stock
More available within 1-3 working days*
SKU: WSPDT2-CB
£25.95

3-£24.65£1.30£25.95
5-£24.00£1.95£25.95
10-£23.36£2.60£25.95
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WCED WMCUSP463C 3 Phase SPD with 63A Curve C 4 Pole MCB

WCED WMCUSP463C 3 Phase SPD with 63A Curve C 4 Pole MCB

Delivery usually within 1-3 working days*
SKU: WMCUSP463C
£59.90

3-£56.91£3.00£59.90
5-£55.41£4.49£59.90
10-£53.91£5.99£59.90
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WCED WRCUSP440C 4 Pole SPD + 4 Pole 40A C Curve Type A RCBO with Metal Enclosure

WCED WRCUSP440C 4 Pole SPD + 4 Pole 40A C Curve Type A RCBO with Metal Enclosure

Delivery usually within 1-3 working days*
SKU: WRCUSP440C
£80.25

3-£76.24£4.01£80.25
5-£74.23£6.02£80.25
10-£72.23£8.03£80.25
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WCED WEC440SPT12 WCED Stand Alone Type 1 & 2 SPD with Main Switch 1WCED WEC440SPT12 WCED Stand Alone Type 1 & 2 SPD with Main Switch 2

WCED Stand Alone Type 1 & 2 SPD with Main Switch

Delivery usually within 1-3 working days*
SKU: WEC440SPT12
£74.25

2-£71.28£2.97£74.25
3-£68.31£5.94£74.25
4-£65.34£8.91£74.25
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WCED WSPD240 Type 2 40kA Surge Arrestor (SPD) 1

Type 2 40kA Surge Arrestor (SPD)

5 In stock
More available within 1-3 working days*
SKU: WSPD240
£17.16

3-£16.30£0.86£17.16
5-£15.87£1.29£17.16
10-£15.44£1.72£17.16
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WCED WFMS100/3FSP WCED Metal Fused Main Switch with 3 Fuses & SPD 1WCED WFMS100/3FSP WCED Metal Fused Main Switch with 3 Fuses & SPD 2

WCED Metal Fused Main Switch with 3 Fuses & SPD

Delivery usually within 1-3 working days*
SKU: WFMS100/3FSP
£65.40

3-£62.13£3.27£65.40
5-£60.50£4.91£65.40
10-£58.86£6.54£65.40
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Live Electrical SA140 Live Electrical 1 Pole 20kA/40kA Type 2 Surge Protective Device

Live Electrical SA140 1 Pole 20kA/40kA Type 2 Surge Protective Device

9 In stock
More available within 1-3 working days*
SKU: SA140
£9.55
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WCED WSPDTE-4 WCED 4 Pole 4 Module Type 1+2 SPD

WCED 4 Pole 4 Module Type 1+2 SPD

3 In stock
More available within 1-3 working days*
SKU: WSPDTE-4
£106.18

3-£100.87£5.31£106.18
5-£98.22£7.96£106.18
10-£95.56£10.62£106.18
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Live Electrical EMCU4-SP Live Electrical 4 Way Metal CU with 20/40kA SPD and 100A Main Switch 1Live Electrical EMCU4-SP Live Electrical 4 Way Metal CU with 20/40kA SPD and 100A Main Switch 2

Live Electrical 4 Way Metal CU with 20/40kA SPD and 100A Main Switch

8 In stock
More available within 1-3 working days*
SKU: EMCU4-SP
£33.99
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Live Electrical SAMODKIT240 Live Electrical SPD Kit SA240 Type 2

Live Electrical SA240 SPD Type 2 Kit

Delivery usually within 1-3 working days*
SKU: SAMODKIT240
£25.90 £21.90
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WCED WRDUSP440C 4 Pole SPD + 40A C Curve Type A RCD with Metal Enclosure

WCED WRDUSP440C 4 Pole SPD + 40A C Curve Type A RCD with Metal Enclosure

Out of stock
This item cannot be back-ordered
SKU: WRDUSP440C
£63.90

3-£60.71£3.20£63.90
5-£59.11£4.79£63.90
10-£57.51£6.39£63.90
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Showing 1–20 of 110 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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