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K2-4PG320-M Mersen Surge Protector Type 2 SPD 4 Pole 277/480 Volt 20KA TT Remote Indication
Mersen 44020409 K2-4PG320-M Type 2 surge protection device for 277/480 V AC TT and TNS systems with 50 kA surge capacity and integrated remote indication.
£129.82
Why Choose the Mersen 44020409 K2-4PG320-M Surge Protection Device?
The Mersen 44020409, also known as the K2-4PG320-M, is a premium Type 2 surge protection device (SPD) designed to safeguard low-voltage electrical installations from transient overvoltages caused by indirect lightning strikes and switching events. Part of the Mersen Surge-Trap® K2 Series, this pluggable four-pole SPD combines high surge capacity with integrated remote status indication, making it ideal for industrial, commercial and critical infrastructure applications.
Designed for 277/480 V AC three-phase networks, the K2-4PG320-M features a 3+1 protection configuration with L-N and N-PE protection modes for TT and TNS earthing systems. With a 20 kA nominal discharge current and 50 kA maximum discharge current, it provides reliable protection for control panels, automation systems, motor control centres and other sensitive electrical equipment.
Its reinforced pluggable design enables rapid replacement of surge modules without removing the DIN rail base, while the integrated microswitch allows remote monitoring through building management systems, PLCs or alarm circuits. This reduces maintenance time and helps ensure continuous protection of critical installations.
Key Advantages
- Reliable Type 2 surge protection for industrial and commercial electrical installations.
- 50 kA maximum discharge current for effective transient suppression.
- 20 kA nominal discharge current for dependable protection performance.
- 277/480 V AC operation for three-phase power systems.
- 3+1 protection configuration supporting TT and TNS networks.
- Integrated remote indication microswitch for status monitoring.
- Visual green status indicator simplifies maintenance inspections.
- Compact DIN rail mounting with pluggable replacement cartridges.
Key Features
- Mersen Surge-Trap® K2 Series.
- Type 2 / IEC Class II surge protection device.
- UL Type 1 Component Assembly.
- Four-pole 3+1 configuration.
- 277/480 V AC nominal operating voltage.
- 320 V AC maximum continuous operating voltage (L-N).
- 20 kA nominal discharge current (In).
- 50 kA maximum discharge current (Imax).
- Integrated remote alarm microswitch.
- Green operational status indicator.
- Pluggable modules for simplified servicing.
- DIN rail mounting.
Advanced Surge Protection with Remote Monitoring
Electrical installations are frequently exposed to damaging voltage transients created by lightning activity, switching operations and utility disturbances. The Mersen 44020409 safely diverts these transient currents away from connected equipment, helping minimise downtime, maintenance costs and premature equipment failure.
Its integrated remote indication contact allows maintenance teams to monitor surge protection status remotely via PLCs, SCADA systems or building management platforms, enabling preventative maintenance and improved operational reliability.
Typical Applications
- Industrial power distribution panels.
- Commercial electrical switchboards.
- Motor control centres.
- Manufacturing and automation systems.
- Building management systems.
- Critical infrastructure and utilities.
- HVAC and process control equipment.
- 277/480 V three-phase electrical installations.
Technical Specifications
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| 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 | Yes | |
| Manufacturer | Mersen | |
| Series | Surge-Trap® K2 Series | |
| Model | K2-4PG320-M | |
| Manufacturer part number | 44020409 | |
| EAN | 8435297887676 | |
| Product type | Type 2 surge protection device | |
| Configuration | TN-S, TT | |
| IEC SPD classification | Class II / Type 2 | |
| UL SPD classification | Type 1 Component Assembly | |
| Nominal operating voltage | 277/480 V AC | |
| Maximum continuous operating voltage (L-N) | 320 V AC | |
| Maximum continuous operating voltage (N-PE) | 255 V AC | |
| Maximum discharge current (Imax) | 50 kA | |
| Voltage protection level (L-N) | ≤1.5 kV | |
| Voltage protection level (N-PE) | ≤1.5 kV | |
| Voltage protection level (L-PE) | ≤1.8 kV | |
| Protection modes | L-N / N-PE | |
| System configuration | TN-S, TT | |
| Number of poles | 4 | |
| Short-circuit current rating | 100 kA | |
| Following current | 100 A | |
| Maximum back-up fuse | 315 A gG | |
| Remote indication | Microswitch | |
| Remote contact rating | 250 V AC / 0.5 A, 30 V DC / 1 A | |
| Protection rating | IP20 | |
| Mounting type | DIN rail | |
| Connection torque | 3 N·m | |
| 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. 0.442 kg | |
| RoHS compliant | Yes | |
| HS Code | 85363090 | |
| Country of Manufacture | Spain |
Frequently Asked Questions
What is the Mersen 44020409 used for?
The Mersen 44020409 is a Type 2 surge protection device designed to protect three-phase electrical systems from transient overvoltages caused by lightning and switching events.
What is the difference between the K2-4PG320 and K2-4PG320-M?
The K2-4PG320-M includes an integrated remote indication microswitch, allowing the operational status of the surge protector to be monitored remotely.
What electrical systems is this SPD suitable for?
The device is designed for 277/480 V AC TT and TNS systems using a four-pole 3+1 protection configuration.
Can the surge protection modules be replaced?
Yes. The pluggable protection cartridges can be replaced individually without removing the complete DIN rail base.
How is the condition of the surge protector monitored?
The unit incorporates both a green visual status indicator and a remote microswitch contact for continuous local and remote condition monitoring.
Trusted Surge Protection from Mersen
Mersen Surge-Trap® K2 Series surge protection devices are trusted worldwide to provide reliable protection against transient overvoltages while supporting the long-term reliability of industrial, commercial and infrastructure electrical systems.
