SKU: 83120125Alt SKU: STPT12-12K440V-2PMMPN: 83120125
Mersen Surge Protector Type 1+2 SPD 2 Pole 230/400 Volt 20KA IT/TNS R.I

Mersen Surge Protector Type 1+2 SPD 2 Pole 230/400 Volt 20KA IT/TNS R.I

Mersen STPT12-12K440V-2PM Type 1+2 pluggable surge protection device with 12.5 kA lightning impulse current, 440 V maximum continuous operating voltage, 2 pole 2+0 IT/TNS configuration, remote indication and DIN rail mounting.

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Why Choose the Mersen 83120125 Surge Protection Device?

The Mersen 83120125 STPT12-12K440V-2PM is a robust Type 1+2 Surge Protection Device (SPD) designed to protect low voltage electrical installations against transient overvoltages caused by lightning strikes and switching events. As part of the Mersen Surge-Trap® Pluggable STPT12 Series, it provides reliable first-stage surge protection for industrial, commercial and infrastructure applications.

This pluggable SPD combines Class I and Class II surge protection in a compact DIN rail mounted format. The replaceable cartridge design, visual indication and integrated remote signalling contact make it suitable for installations where straightforward maintenance and system monitoring are important.

With a 12.5 kA lightning impulse current rating, 440 V maximum continuous operating voltage and 2-pole 2+0 IT/TNS configuration, the Mersen 83120125 is ideal for protecting distribution boards, control panels, automation equipment and sensitive electrical systems from damaging voltage surges.

Key Advantages

  • Combined Type 1+2 surge protection for incoming electrical installations.
  • 12.5 kA lightning impulse current (Iimp) for reliable surge handling.
  • 440 V maximum continuous operating voltage for IT and TNS systems.
  • Integrated remote indication for monitoring SPD status.
  • Pluggable cartridge design for quick maintenance and replacement.
  • Compact 2-pole, 2-module DIN rail format.

Key Features

  • Mersen Surge-Trap® Pluggable STPT12 Series.
  • Type 1+2 / Class I+II surge protection device.
  • 12.5 kA Iimp (10/350 μs).
  • 50 kA maximum discharge current (Imax 8/20 μs).
  • 400 V AC nominal operating voltage.
  • 440 V maximum continuous operating voltage.
  • 2-pole configuration for 2+0 IT / TNS systems.
  • Remote signalling contact for status monitoring.
  • DIN rail mounted IP20 construction.

Reliable Protection Against Electrical Surges

Surge protection devices help protect electrical systems by safely limiting transient overvoltages before they reach connected equipment. This reduces the risk of damage to switchgear, control systems, drives, PLCs, instrumentation and other sensitive electrical components.

The Mersen STPT12 range is designed for use as the first level of protection in main distribution boards and incoming power supply panels. Its Type 1+2 rating makes it suitable for installations exposed to atmospheric surges and locations requiring coordinated protection against lightning currents and voltage spikes.

Typical Applications

  • Main low voltage distribution boards.
  • Incoming power supply panels.
  • Industrial automation and control systems.
  • Commercial building electrical installations.
  • Switchboards and panel building.
  • Infrastructure, utilities and exposed electrical networks.

Technical Specifications

Voltage 400 V
Manufacturer Mersen
Series Surge-Trap® Pluggable STPT12
Model STPT12-12K440V-2PM
SKU 83120125
Product type Type 1+2 Surge Protection Device
IEC classification Class I+II
Lightning impulse current (Iimp) 12.5 kA (10/350 μs)
Maximum discharge current (Imax) 50 kA (8/20 μs)
Nominal operating voltage (Un) 400 V AC
Maximum continuous operating voltage (Uc) 440 V
System configuration 2+0 IT / TNS
Network type 1Ph+N, 230 / 400 V AC
Number of poles 2
Number of modules 2
Mounting type 35 mm DIN rail
Protection rating IP20
Remote indication Yes
Format Pluggable
Dimensions (W × H × D) approx. 42 × 90 × 117 mm
Weight approx. 0.382 kg
HS Code 85363090
Country of Manufacture Spain

Frequently Asked Questions

What is the Mersen 83120125 used for?

It is used to protect low voltage electrical installations from transient overvoltages caused by lightning and switching events.

What type of surge protection does this device provide?

The Mersen 83120125 provides combined Type 1+2 / Class I+II surge protection.

Does this SPD include remote indication?

Yes. The device includes remote indication, allowing the surge protection status to be monitored externally.

What is the maximum continuous operating voltage?

The Mersen 83120125 has a 440 V maximum continuous operating voltage.

Where is this surge protection device typically installed?

It is typically installed on a DIN rail inside main distribution boards, incoming panels or electrical switchboards.

Trusted for Critical Power Protection

Mersen Surge-Trap® surge protection devices are trusted by electrical engineers, panel builders and industrial facilities worldwide for dependable protection of electrical distribution systems and sensitive connected equipment.

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