Mersen 44020405 K2-4P275-M four-pole Type 2 surge protection device for 230/400 V AC TNS systems, featuring a 20 kA nominal discharge current, 50 kA maximum discharge current and integrated remote indication.
£158.67
The Mersen 44020405, also known as the K2-4P275-M, is a high-performance Type 2 surge protection device (SPD) designed to protect low-voltage electrical installations against transient overvoltages caused by induced lightning surges and electrical switching events. Part of the Mersen Surge-Trap® K2 Series, this four-pole, pluggable device provides dependable surge protection for three-phase TNS power distribution systems.
Featuring a 4+0 internal configuration, the K2-4P275-M provides L-PE and N-PE protection across four poles. It has a nominal discharge current of 20 kA and a maximum discharge current of 50 kA, helping protect industrial machinery, automation equipment, control panels and sensitive electronic systems from damaging voltage transients.
The Mersen 44020405 is designed for 230/400 V AC networks and has a maximum continuous operating voltage of 275 V AC. Its integrated microswitch provides remote status indication, allowing the condition of the SPD to be monitored through a PLC, alarm circuit, SCADA platform or building management system. Pluggable protection cartridges and DIN rail mounting also simplify installation and maintenance.
Transient overvoltages can be generated by indirect lightning activity, utility network disturbances and the switching of motors, transformers or other inductive loads. These short-duration voltage spikes may damage control equipment, power supplies, variable speed drives and other sensitive electrical devices.
The Mersen K2-4P275-M safely diverts surge current away from connected equipment while its integrated microswitch provides a remote indication of device condition. Maintenance teams can connect this contact to an alarm, PLC or building management system, allowing deterioration or end-of-life status to be identified without manually inspecting the distribution board.
| Voltage | 400 V |
|---|---|
| Phase | Three Phase |
| Manufacturer | Mersen |
| Series | Surge-Trap® K2 Series |
| Model | K2-4P275-M |
| Manufacturer part number | 44020405 |
| EAN / UPC | 8435297889946 |
| Product type | Surge protection device |
| IEC SPD classification | Class II |
| EN SPD classification | Type 2 |
| UL SPD classification | Type 1 Component Assembly |
| Internal configuration | 4+0 |
| Nominal operating voltage | 230/400 V AC |
| Nominal frequency | 50 / 60 Hz |
| Maximum continuous operating voltage | 275 V AC |
| Nominal discharge current, In | 20 kA |
| Maximum discharge current, Imax | 50 kA |
| Voltage protection level, Up | ≤1.5 kV |
| Typical surge current | 5 kA over 200 impulses |
| Response time | ≤25 ns |
| Residual current | <1 mA |
| Protection modes | L-PE / N-PE |
| System configuration | TNS |
| Number of poles | 4 |
| DIN rail modules | 4 |
| IEC short-circuit withstand | 25 kA |
| UL short-circuit current rating | 85 kA |
| Maximum back-up fuse | 315 A gG |
| Thermal disconnection | Dynamic |
| Thermal protection behaviour | Open Circuit Mode |
| Remote indication | Integrated microswitch |
| Remote contact rating | 250 V AC at 0.5 A / 30 V DC at 1 A |
| Status indication | Green operational / not green replace |
| Protection rating | IP20 |
| Mounting type | DIN rail |
| Connection torque | 3 N·m |
| Solid conductor capacity | 1.5–35 mm² |
| Stranded conductor capacity | 1.5–25 mm² |
| Remote indication conductor capacity | 0.5–1.5 mm² |
| Operating temperature | -40 to +85 °C |
| Operating humidity | 5–95% |
| Maximum installation altitude | 4,000 m |
| Housing material | PA6 CT1 and PA66 CT1 |
| Housing colour | Grey, RAL 7035 |
| Flammability rating | UL94 V-0 |
| Replacement cartridge | Mersen 44020001 K2-275 |
| Dimensions (H × W × D) | 90 × 72 × 74.4 mm |
| Weight | approx. 0.435 kg |
| RoHS compliant | Yes |
| HS Code | 85363090 |
| Country of Manufacture | Spain |
The Mersen 44020405 is a Type 2 surge protection device used to protect three-phase TNS electrical installations and connected equipment against transient overvoltages caused by induced lightning surges and switching events.
The K2-4P275-M includes an integrated microswitch for remote status indication, while the standard K2-4P275 provides visual condition indication without the remote monitoring contact.
The device has a nominal discharge current of 20 kA and a maximum discharge current of 50 kA using an 8/20 µs surge waveform.
The Mersen 44020405 is designed for 230/400 V AC TNS systems and uses a four-pole 4+0 internal protection configuration.
Yes. The device uses pluggable protection cartridges, allowing individual modules to be replaced without removing the complete DIN rail base from the electrical panel.
Mersen Surge-Trap® K2 Series devices provide dependable protection against transient overvoltages while supporting electrical safety, equipment reliability and service continuity in demanding industrial and commercial installations.
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