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K2-4P275 Mersen Surge Protector Type 2 SPD 4 Pole 230/400 Volt 20KA TNS

K2-4P275 Mersen Surge Protector Type 2 SPD 4 Pole 230/400 Volt 20KA TNS

Mersen 44020404 K2-4P275 Type 2 surge protection device for 230/400 V AC TNS systems with a 4+0 configuration, 20 kA nominal discharge current and 50 kA maximum discharge current.

SKU: 44020404Alt SKU: K2-4P275MPN: 44020404
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List Price £135.62 ex VAT
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Why Choose the Mersen 44020404 K2-4P275 Surge Protection Device?

The Mersen 44020404, also known as the K2-4P275, is a robust Type 2 surge protection device (SPD) designed to protect low-voltage electrical installations against transient overvoltages caused by indirect lightning strikes and switching events. As part of the Mersen Surge-Trap® K2 Series, this pluggable four-pole SPD provides reliable protection for 230/400 V AC TNS electrical systems.

Featuring a 4+0 protection configuration, the K2-4P275 protects all live conductors individually, making it particularly suitable for TNS earthing systems. With a 20 kA nominal discharge current and a 50 kA maximum discharge current, it safeguards sensitive electrical equipment including control panels, switchboards, automation systems and industrial machinery.

Its reinforced pluggable design allows rapid replacement of protection cartridges without removing the DIN rail base. A built-in visual status indicator provides immediate confirmation of operational status, helping minimise maintenance time while ensuring continuous surge protection.

Key Advantages

  • Reliable Type 2 surge protection for three-phase TNS electrical systems.
  • 50 kA maximum discharge current for effective protection against transient overvoltages.
  • 20 kA nominal discharge current for dependable long-term performance.
  • 4+0 protection configuration providing individual protection on all phases.
  • Designed specifically for 230/400 V AC TNS networks.
  • Pluggable cartridges enable quick maintenance and replacement.
  • Visual end-of-life indicator simplifies routine inspection.
  • Compact DIN rail mounting for straightforward installation.

Key Features

  • Mersen Surge-Trap® K2 Series.
  • Type 2 / IEC Class II surge protection device.
  • UL Type 1 Component Assembly.
  • Four-pole 4+0 configuration.
  • 230/400 V AC nominal operating voltage.
  • 275 V AC maximum continuous operating voltage (Uc).
  • 20 kA nominal discharge current (In).
  • 50 kA maximum discharge current (Imax).
  • Visual operational status indicator.
  • Reinforced pluggable surge protection modules.
  • DIN rail mounting.
  • Suitable for TNS earthing systems.

Reliable Protection for TNS Electrical Installations

Electrical equipment is vulnerable to damaging voltage transients generated by lightning activity, switching operations and utility disturbances. The Mersen K2-4P275 safely diverts these surge currents away from connected equipment, helping reduce costly downtime and extending the service life of electrical assets.

Its 4+0 architecture provides dedicated protection for each live conductor within TNS systems, making it an excellent choice for industrial switchboards, commercial distribution panels and critical electrical infrastructure where dependable surge protection is essential.

Typical Applications

  • Industrial electrical distribution boards.
  • Commercial switchboards.
  • Motor control centres.
  • Automation and PLC control panels.
  • Building services installations.
  • Manufacturing facilities.
  • HVAC control systems.
  • TNS low-voltage electrical networks.

Technical Specifications

Voltage 400 V
Phase Three Phase
Manufacturer Mersen
Series Surge-Trap® K2 Series
Model K2-4P275
Manufacturer part number 44020404
Product type Type 2 surge protection device
Configuration TN-S
IEC SPD classification Type 2 / Class II
UL SPD classification Type 1 Component Assembly
Nominal operating voltage 230/400 V AC
Maximum continuous operating voltage (Uc) 275 V AC
Nominal Discharge Current (In) 20 kA
Maximum discharge current (Imax) 50 kA
Voltage protection level (Up) ≤1.5 kV
System configuration TN-S
Number of poles 4
Short-circuit current rating 25 kA
Maximum back-up fuse 315 A gG
Protection rating IP20
Mounting type DIN rail
Connection torque 3 N·m
Solid conductor capacity 1.5 to 35 mm²
Stranded conductor capacity 1.5 to 25 mm²
Operating temperature -40 to +85 °C
Maximum installation altitude 4,000 m
Housing material PA6 CT1 & PA66 CT1
Flammability rating UL94 V-0
Dimensions (H × W × D) 90 × 72 × 74.4 mm
Weight approx. 0.435 kg
RoHS compliant Yes
HS Code 85363090
Country of Manufacture Spain
Poles 4-pole
Device Type Surge protection device
SPD Type Type 2
Earthing System TN-S
Nominal Discharge Current (In) 20 kA
Remote Signal No

Frequently Asked Questions

What is the Mersen 44020404 used for?

The Mersen 44020404 is a Type 2 surge protection device that protects three-phase TNS electrical installations from transient overvoltages caused by lightning and switching events.

What is the difference between the K2-4P275 and K2-4PG275?

The K2-4P275 uses a 4+0 configuration for TNS systems, while the K2-4PG275 features a 3+1 configuration designed primarily for TT and TNS networks.

What surge current can the K2-4P275 withstand?

The device has a nominal discharge current of 20 kA and a maximum discharge current of 50 kA per phase.

Can the protection modules be replaced?

Yes. The surge protection cartridges are fully pluggable, allowing individual modules to be replaced without removing the complete base from the DIN rail.

Where is the Mersen K2-4P275 typically installed?

The device is commonly installed in electrical distribution boards, industrial control panels and commercial switchboards operating on 230/400 V AC TNS systems.

Trusted Surge Protection from Mersen

Mersen Surge-Trap® K2 Series surge protection devices help improve electrical system reliability by protecting valuable equipment against damaging transient overvoltages in commercial, industrial and infrastructure installations.

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