BG Electrical CUSPDT21N Type 2 Single Phase Surge Protection Device

BG CUSPDT21N — Type 2 Single-Phase 40kA Surge Protection Device (SPD), 1-Module

The BG CUSPDT21N is a Type 2 single-phase surge protection device designed to protect domestic installations from transient overvoltages caused by lightning events, switching surges and grid disturbances. Rated at 40kA, it rapidly diverts damaging surge energy to earth in under 25ns, safeguarding all downstream circuits and connected equipment.

Its compact single-module design ensures it fits neatly into any BG Fortress consumer unit or enclosure, providing a fast, compliant way to meet BS 7671 requirements for surge protection.

The CUSPDT21N provides robust surge protection using coordinated internal pathways for both L-N and N-PE, delivering:

20kA nominal discharge current (L-N / N-PE)

40kA maximum discharge capacity

<1.5kV voltage protection level for sensitive equipment

<25ns disconnection speed

This ensures effective mitigation of transient overvoltages for the entire installation.

Designed with installers in mind, the SPD features:

Simple DIN-rail mounting

Positive visual status indicator — green = OK, red = replace

1.5–6mm² terminal capacity with secure torque settings

Compatible with 100A gG back-up fuses

At only 18mm wide, it maximises space inside modern consumer units while ensuring full system protection.

Features of the BG Type 2 Single Phase Surge Protection Device:

• Type 2 Single-Phase SPD for Domestic Installations
• 40kA Maximum Surge Discharge Capacity
• Fast
• Voltage Protection Level <1.5kV
• Nominal Discharge Current: 20kA (L–N / N–PE)
• Single-Module Width Compatible with BG Fortress Consumer Units
• Positive Status Indication (Green = OK, Red = Replace)
• DIN-Rail Mounted for Quick Installation
• Terminal Capacity 1.5–6mm² with Defined Torque Settings
• Compliant with BS EN 61643-11, BS EN 62305 & BS 7671

View All Surge Protection Devices

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