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K1-4PG320-M Mersen Surge Protector Type 1+2 SPD 4 Pole 277/480 Volt 20KA TT Remote Indication

K1-4PG320-M Mersen Surge Protector Type 1+2 SPD 4 Pole 277/480 Volt 20KA TT Remote Indication

Mersen K1-4PG320-M Type 1+2 surge protection device with integrated remote signalling, 320 V AC operating voltage, 3+1 configuration and pluggable DIN rail mounting for TT and TNS 277/480 V AC electrical systems.

SKU: 44120409Alt SKU: K1-4PG320-MMPN: 44120409
Price
List Price £403.75 ex VAT
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Manufacturer Lead Time

£403.75

Why Choose the Mersen 44120409 K1-4PG320-M Surge Protection Device?

The Mersen 44120409 K1-4PG320-M is a premium Type 1+2 Surge Protection Device (SPD) engineered to protect three-phase low-voltage electrical installations from lightning currents and transient overvoltages. Part of the trusted Mersen Surge-Trap® K - K1 Series, this pluggable surge protector combines exceptional surge protection with integrated remote signalling, making it ideal for industrial, commercial and critical infrastructure applications.

Designed for installation within the main distribution board, the K1-4PG320-M features a modular pluggable construction that enables rapid replacement of protection cartridges during servicing. Its integrated microswitch allows remote monitoring of the device status, enabling maintenance personnel to receive fault notifications without opening the enclosure, reducing downtime and simplifying preventative maintenance.

With a 320 V AC maximum continuous operating voltage (Uc), a 3+1 protection configuration and a 12.5 kA lightning impulse current (Iimp), the K1-4PG320-M is designed for TT and TNS 277/480 V AC three-phase electrical systems, providing dependable protection against direct lightning currents and switching surges.

Key Advantages

  • High-performance Type 1+2 surge protection for three-phase installations.
  • Integrated remote signalling microswitch for continuous status monitoring.
  • 3+1 protection configuration optimised for TT and TNS systems.
  • Pluggable cartridge design enables fast servicing and replacement.
  • Compact DIN rail mounted housing saves valuable enclosure space.
  • Protects sensitive electrical equipment against lightning strikes and transient overvoltages.

Key Features

  • Mersen Surge-Trap® K - K1 Series.
  • IEC Class I+II / Type 1+2 surge protection device.
  • 320 V AC maximum continuous operating voltage (Uc).
  • 12.5 kA lightning impulse current (Iimp).
  • 20 kA nominal discharge current (In).
  • 50 kA maximum discharge current (Imax).
  • Four-pole 3+1 protection configuration.
  • Integrated remote indication microswitch.
  • Green (OK) / Not Green (Replace) visual status indication.
  • Compact pluggable DIN rail mounted construction.

Reliable Protection Against Electrical Surges

The Mersen K1-4PG320-M safely diverts damaging lightning currents and transient overvoltages away from connected electrical equipment before they can affect switchgear, PLCs, variable speed drives, automation systems and other sensitive electronics. This helps reduce maintenance costs, minimise downtime and improve overall installation reliability.

Its combination of high surge capacity, integrated remote monitoring and pluggable cartridge design makes it an ideal solution for industrial facilities, commercial buildings, utilities, renewable energy installations and other critical power distribution systems.

Typical Applications

  • Main three-phase distribution boards.
  • Industrial automation systems.
  • Commercial buildings.
  • Manufacturing facilities.
  • Infrastructure projects.
  • Renewable energy installations.
  • Water treatment plants.
  • TT and TNS 277/480 V AC three-phase electrical systems.

Technical Specifications

SPD Type Type 1+2
Voltage 480 V
Phase Three Phase
Manufacturer Mersen
Series Surge-Trap® K - K1 Series
Model K1-4PG320-M
Part Number 44120409
EAN 8435297887690
Product type Type 1+2 Surge Protection Device (SPD)
IEC SPD Type Class I+II
UL SPD Type Type 1 Component Assembly
Maximum continuous operating voltage (Uc) 320 V AC (L-N), 255 V AC (N-PE)
Nominal operating voltage (Un) 277/480 V AC
Lightning impulse current (Iimp) 12.5 kA (L-N), 50 kA (N-PE)
Nominal Discharge Current (In) 20 kA (L-N), 50 kA (N-PE)
Maximum discharge current (Imax) 50 kA (L-N), 100 kA (N-PE)
Protection modes L-N / N-PE
Configuration TN-S, TT
Number of poles 4
System compatibility TN-S, TT
Protection level (Up) ≤1.5 kV
Following current (Ifi) 100 A
Rated short-circuit withstand (ISCCR) 25 kA
Remote indication Integrated microswitch
Maximum back-up fuse 315 A gG
Mounting type DIN rail
Format Pluggable
Housing material PA6 CT1 & PA66 CT1
Protection rating IP20
Operating temperature -40°C to +80°C
Tightening torque 3 Nm
Dimensions (H × W × D) Approx. 90 × 72 × 90 mm
Weight Approx. 0.616 kg
RoHS compliant Yes
Poles 4-pole
Device Type Surge protection device
Earthing System TN-S, TT
Nominal Discharge Current (In) 20 kA
Remote Signal Yes

Frequently Asked Questions

What is the Mersen 44120409 K1-4PG320-M used for?

It provides Type 1+2 surge protection for three-phase electrical installations against lightning currents, switching surges and transient overvoltages.

Does this model include remote monitoring?

Yes. The K1-4PG320-M includes an integrated microswitch that enables remote indication of the surge protection device status for easier maintenance planning.

Which electrical systems is this SPD suitable for?

The device is designed for TT and TNS 277/480 V AC three-phase electrical distribution systems.

What surge current ratings does the device provide?

The SPD provides a 12.5 kA lightning impulse current, 20 kA nominal discharge current and 50 kA maximum discharge current on the line modules.

How is the K1-4PG320-M installed?

The surge protection device installs onto a standard DIN rail inside the main electrical distribution board and features replaceable pluggable cartridges for fast servicing.

Trusted Protection for Critical Electrical Systems

Mersen Surge-Trap® K Series surge protection devices are trusted by electrical engineers and panel builders worldwide to deliver dependable protection against lightning strikes and transient overvoltages in critical power distribution installations.

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