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K2-3P440 Mersen Surge Protector Type 2 SPD 3 Pole 400/690 Volt 20KA IT

K2-3P440 Mersen Surge Protector Type 2 SPD 3 Pole 400/690 Volt 20KA IT

Mersen 44020308 K2-3P440 Type 2 three-pole surge protection device for 400/690 V TN-C systems with 440 V AC maximum continuous operating voltage, 20 kA nominal discharge current and 50 kA maximum discharge current.

SKU: 44020308Alt SKU: K2-3P440MPN: 44020308
Price
List Price £112.16 ex VAT
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Why Choose the Mersen 44020308 K2-3P440 Surge Protection Device?

The Mersen 44020308, also identified as the K2-3P440, is a robust Type 2 surge protection device (SPD) engineered to protect three-phase low-voltage electrical installations from transient overvoltages. Part of the proven Mersen Surge-Trap K2 series, it is designed for 400/690 V TN-C electrical systems and is also suitable for 400 V IT network configurations, providing dependable protection against lightning-induced surges and switching transients.

Its reinforced pluggable design enables protection cartridges to be replaced quickly without removing the complete DIN-rail base, reducing maintenance time and minimising system downtime. A clear visual status indicator allows engineers to verify the operating condition instantly, ensuring surge protection remains fully operational.

Featuring a 440 V AC maximum continuous operating voltage, 20 kA nominal discharge current and 50 kA maximum discharge current, the Mersen K2-3P440 delivers reliable secondary surge protection for industrial switchgear, commercial distribution boards, motor control centres and critical infrastructure applications.

Key Advantages

  • Reliable Type 2 surge protection for three-phase 400/690 V electrical systems.
  • 50 kA maximum discharge current provides excellent transient overvoltage protection.
  • Suitable for TN-C systems and compatible with 400 V IT networks.
  • Replaceable pluggable cartridges simplify servicing and maintenance.
  • Visual status indication allows rapid inspection.
  • Compact three-module DIN-rail installation.

Key Features

  • Mersen Surge-Trap K2 series.
  • Type 2 / Class II surge protection device.
  • Three-pole (3+0) configuration.
  • 400/690 V AC nominal operating voltage.
  • 440 V AC maximum continuous operating voltage (Uc).
  • 20 kA nominal discharge current (In).
  • 50 kA maximum discharge current (Imax).
  • Protection mode: L-PE(N).
  • Dynamic thermal disconnection.
  • Visual operating status indication.
  • Replaceable plug-in cartridges.
  • DIN-rail mounting.

Reliable Protection for 400/690 V Three-Phase Systems

Transient overvoltages generated by indirect lightning strikes, switching operations, motors, transformers and other inductive loads can rapidly damage PLCs, drives, communication equipment, power supplies and control electronics. Installing a dedicated Type 2 surge protection device significantly reduces the risk of equipment failure and costly downtime.

The Mersen K2-3P440 combines high surge handling capability with fast response and replaceable protection cartridges, delivering dependable long-term protection whilst simplifying preventative maintenance in demanding industrial environments.

Typical Applications

  • 400/690 V TN-C distribution boards.
  • 400 V IT electrical installations.
  • Industrial switchgear.
  • Motor control centres.
  • Commercial power distribution systems.
  • PLC and automation control panels.

Technical Specifications

Voltage 690 V
Phase Three Phase
Manufacturer Mersen
Series Surge-Trap K2
Model K2-3P440
SKU / Part number 44020308
Product type Surge protection device
IEC SPD classification Type 2 / Class II
UL SPD classification Type 1 Component Assembly
Configuration TN-C (also suitable for 400 V IT)
Number of poles 3
System configuration TN-C (also suitable for 400 V IT)
Protection mode L-PE(N)
Nominal operating voltage 400/690 V AC
Maximum continuous operating voltage 440 V AC
Nominal discharge current 20 kA
Maximum discharge current 50 kA
Voltage protection level ≤2.0 kV
Response time ≤25 ns
Residual current <1 mA
Short-circuit withstand rating 25 kA
Maximum back-up fuse 315 A gG
Dynamic thermal disconnection Yes
Thermal protection behaviour Open Circuit Mode (OCM)
Status indication Green (OK) / Not green (replace)
Remote signalling No
Mounting type DIN rail
DIN rail modules 3
Housing material PA6 CT1 & PA66 CT1
Terminal tightening torque 3 Nm
Replacement cartridge Cartridge ID C34
Weight approx. 0.391 kg
EAN 8435297889915
RoHS compliant Yes
HS Code 85363090
Country of Manufacture Spain
Poles 3-pole
Device Type Surge protection device
SPD Type Type 2
Earthing System IT, TN-C
Nominal Discharge Current (In) 20 kA
Remote Signal No

Frequently Asked Questions

What is the Mersen 44020308 used for?

The Mersen 44020308 protects three-phase 400/690 V electrical installations from transient overvoltages caused by lightning activity, switching events and inductive loads.

What type of surge protection device is the K2-3P440?

It is a Type 2 / Class II surge protection device designed for secondary surge protection in low-voltage electrical installations.

Which electrical systems are compatible with this SPD?

The K2-3P440 is designed for TN-C 400/690 V systems and is also suitable for 400 V IT network configurations.

What discharge current can the device withstand?

The device provides a 20 kA nominal discharge current and a 50 kA maximum discharge current using the standard 8/20 µs surge waveform.

Can the protection cartridges be replaced?

Yes. The pluggable construction allows the protection cartridges to be replaced without removing the complete DIN-rail base, reducing maintenance time.

Trusted Surge Protection from Mersen

Mersen Surge-Trap K2 surge protection devices are trusted by electrical engineers, panel builders and maintenance professionals to protect critical three-phase electrical systems against damaging transient overvoltages.

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