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Mersen Surge Protector Type 1+2 SPD 4 Pole 230/400:400/690 Volt 20KA IT

Mersen Surge Protector Type 1+2 SPD 4 Pole 230/400:400/690 Volt 20KA IT

Mersen STPT12-12K440V-4P Type 1+2 surge protection device with 12.5 kA lightning impulse current rating and 440 V UC for 230/400 V AC and 400/690 V AC three-phase plus neutral systems.

SKU: 83120148Alt SKU: STPT12-12K440V-4PMPN: 83120148
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List Price £333.54 ex VAT
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Why Choose the Mersen 83120148 STPT12-12K440V-4P Surge Protection Device?

The Mersen 83120148 STPT12-12K440V-4P is a high-performance Type 1+2 Surge Protection Device (SPD) designed to protect low-voltage electrical installations from lightning currents and transient overvoltages. Developed for industrial, commercial and infrastructure environments, it helps protect distribution systems, control panels and sensitive electrical equipment from damaging surge events.

Part of the trusted Mersen Surge-Trap® STPT12 Series, this pluggable DIN rail mounted surge protection device combines lightning current discharge capability with transient overvoltage protection in a compact modular design. It is suitable as the first stage of surge protection in main distribution boards and incoming power supply panels.

Designed for 230/400 V AC and 400/690 V AC three-phase plus neutral (3Ph+N) systems, the STPT12-12K440V-4P provides a 12.5 kA Iimp (10/350 μs) lightning impulse current rating. Its 440 V UC maximum continuous operating voltage makes it suitable for higher voltage installations requiring dependable surge protection.

Key Advantages

  • Combined Type 1+2 surge protection for lightning currents and transient overvoltages.
  • 12.5 kA Iimp (10/350 μs) lightning impulse current capability.
  • Suitable for 230/400 V AC and 400/690 V AC three-phase systems.
  • 440 V UC maximum continuous operating voltage.
  • 4-pole pluggable modular design for easier servicing.
  • DIN rail mounting for quick installation in electrical distribution panels.
  • Ideal as first-stage surge protection in incoming power supply panels.

Key Features

  • Mersen Surge-Trap® STPT12 Series.
  • Type 1+2 / Class I+II surge protection device.
  • 12.5 kA Iimp (10/350 μs) lightning impulse current.
  • 50 kA Imax (8/20 μs) maximum discharge current.
  • 20 kA In (8/20 μs) nominal discharge current.
  • 400/690 V AC nominal operating voltage.
  • 440 V UC maximum continuous operating voltage.
  • 4-pole, 4-module pluggable format.

Reliable Protection Against Lightning and Voltage Surges

Surge protection devices help reduce the risk of equipment damage caused by lightning strikes, switching operations and transient overvoltage events. Installing a Type 1+2 SPD at the main distribution board provides a robust first line of defence for downstream electrical equipment and control systems.

The Mersen STPT12 series is engineered for demanding electrical environments, offering dependable surge protection for switchboards, automation systems, industrial machinery, commercial facilities and infrastructure installations where operational continuity is essential.

Typical Applications

  • Main electrical distribution boards.
  • Industrial automation systems.
  • Commercial building electrical installations.
  • Manufacturing facilities.
  • Infrastructure and utility installations.
  • Electrical control panels and switchboards.
  • Higher voltage three-phase distribution systems.

Technical Specifications

Voltage 690 V
Phase Three Phase
Manufacturer Mersen
Series Surge-Trap® STPT12
Model STPT12-12K440V-4P
Part number 83120148
Product type Type 1+2 Surge Protection Device
IEC classification Class I+II
Nominal operating voltage (Un) 400/690 V AC
Maximum continuous operating voltage (Uc) 440 V AC
System configuration TN-S (also suitable for 230/400 V IT)
Protection modes L-PE / N-PE
Lightning impulse current (Iimp) 12.5 kA (10/350 μs)
Maximum discharge current (Imax) 50 kA (8/20 μs)
Number of poles 4
Number of modules 4
Mounting type DIN rail
Format Pluggable
Standards EN 61643-11 / IEC 61643-11
RoHS compliant Yes
HS Code 85363090
Country of Manufacture Spain
Poles 4-pole
Device Type Surge protection device
SPD Type Type 1+2
Earthing System IT, TN-S
Nominal Discharge Current (In) 20 kA
Remote Signal No

Frequently Asked Questions

What is the Mersen 83120148 used for?

It is used to protect low-voltage electrical installations against lightning currents and transient overvoltages.

What type of surge protection device is this?

The 83120148 is a Type 1+2 / Class I+II surge protection device designed for lightning current discharge and transient overvoltage protection.

What electrical system is this device designed for?

It is designed for 230/400 V AC and 400/690 V AC three-phase plus neutral installations using 4+0 IT or TNS configurations.

What does the 440 V UC rating mean?

The 440 V UC rating refers to the maximum continuous operating voltage that the surge protection device can withstand during normal operation.

Where should this SPD be installed?

It is typically installed in the main incoming distribution board as the first stage of surge protection for the electrical installation.

Trusted for Industrial Electrical Protection

Mersen Surge-Trap® surge protection devices are trusted by electrical engineers, panel builders and industrial facilities worldwide to provide dependable protection against lightning currents, switching surges and transient overvoltages.

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