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Mersen 44020408 K2-4PG320 Type 2 surge protection device for 277/480 V AC TT and TNS systems with 20 kA nominal discharge current and 50 kA maximum discharge current.
£112.89
The Mersen 44020408, also known as the K2-4PG320, is a high-performance Type 2 surge protection device (SPD) engineered to safeguard low-voltage electrical installations against transient overvoltages caused by lightning activity and switching events. Part of the trusted Mersen Surge-Trap® K2 Series, this four-pole SPD is designed for reliable protection of three-phase power distribution systems operating on 277/480 V AC networks.
With a 20 kA nominal discharge current and a 50 kA maximum discharge current, the K2-4PG320 delivers dependable protection for electrical panels, industrial machinery, commercial buildings and critical infrastructure. Its pluggable construction enables rapid replacement of protection modules while reducing maintenance time and system downtime.
Designed with a 3+1 protection configuration, the device provides effective L-N and N-PE protection for TT and TNS earthing systems. The integrated visual status indicator allows maintenance personnel to verify operational status at a glance, ensuring continued protection of valuable electrical equipment.
Voltage transients generated by indirect lightning strikes, utility switching and large inductive loads can damage automation equipment, control panels, drives and other sensitive electrical systems. The Mersen K2-4PG320 safely diverts surge currents away from connected equipment, reducing the risk of costly failures and downtime.
Its compact pluggable design makes installation and maintenance straightforward, while the robust construction ensures long service life in demanding industrial and commercial environments.
Tick the specs you need, then view products that match.
| Voltage | 480 V | |
|---|---|---|
| Phase | Three Phase | |
| Poles | 4-pole | |
| Device Type | Surge protection device | |
| SPD Type | Type 2 | |
| Earthing System | TN-S, TT | |
| Nominal Discharge Current (In) | 20 kA | |
| Remote Signal | No | |
| Manufacturer | Mersen | |
| Series | Surge-Trap® K2 Series | |
| Model | K2-4PG320 | |
| Manufacturer part number | 44020408 | |
| Product type | Type 2 surge protection device | |
| Configuration | TN-S, TT | |
| IEC SPD classification | Type 2 / Class II | |
| UL classification | Type 1 Component Assembly | |
| Nominal operating voltage | 277/480 V AC | |
| Maximum continuous operating voltage (Uc) | 320 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, TT | |
| Protection modes | L-N / N-PE | |
| Number of poles | 4 | |
| Short-circuit withstand (SCCR) | 85 kA | |
| Maximum back-up fuse | 315 A gG | |
| Protection rating | IP20 | |
| Mounting type | DIN rail | |
| Connection torque | 3 N·m | |
| Operating temperature | -40 to +85 °C | |
| Maximum 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. 0.442 kg | |
| HS Code | 85363090 | |
| Country of Manufacture | Spain |
The Mersen 44020408 is a Type 2 surge protection device designed to protect three-phase electrical installations from transient overvoltages caused by lightning and switching events.
It is designed for 277/480 V AC TT and TNS systems using a four-pole 3+1 protection configuration.
The surge protector provides a nominal discharge current of 20 kA and a maximum discharge current of 50 kA.
Yes. The K2-4PG320 features pluggable cartridges that allow damaged protection modules to be replaced without removing the complete base.
The integrated visual indicator displays green during normal operation and changes when replacement of the protection module is required.
Mersen Surge-Trap® surge protection devices are trusted worldwide to improve electrical system reliability and protect valuable industrial, commercial and infrastructure assets against damaging transient overvoltages.
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