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K1-3P320-M Mersen Surge Protector Type 1+2 SPD 3 Pole 480 Volt 20KA TNC Remote Indication
Mersen 44120305 K1-3P320-M Type 1+2 surge protection device with 320 V AC maximum operating voltage, remote signalling, 12.5 kA lightning impulse current and pluggable DIN rail construction for three-phase TNC systems.
£224.81
Why Choose the Mersen 44120305 K1-3P320-M Surge Protection Device?
The Mersen 44120305 K1-3P320-M is a high-performance Type 1+2 Surge Protection Device (SPD) designed to protect three-phase low-voltage electrical installations against lightning currents and transient overvoltages. As part of the established Mersen Surge-Trap® K - K1 Series, this pluggable surge protector provides first-level protection for industrial, commercial and infrastructure power distribution systems.
Designed for installation within a main distribution board, the K1-3P320-M combines substantial surge-handling capability with a compact DIN rail mounted format. Its replaceable pluggable modules simplify maintenance, while the integrated microswitch enables remote monitoring of the device condition from a control panel, building management system or other signalling circuit.
With a 320 V AC maximum continuous operating voltage (Uc), a 3+0 protection configuration and a 12.5 kA lightning impulse current per pole, the K1-3P320-M is suitable for three-phase TNC systems with a nominal operating voltage of 277/480 V AC. Its visual condition indicators and remote signalling contact help maintenance teams identify when replacement is required.
Key Advantages
- Combined Type 1+2 protection against lightning currents and induced voltage surges.
- Integrated remote signalling microswitch for convenient condition monitoring.
- Pluggable modular construction simplifies maintenance and cartridge replacement.
- Suitable for 277/480 V AC three-phase TNC systems.
- Compact DIN rail design supports space-efficient panel installation.
- Helps protect switchgear, drives, controls and other sensitive electrical equipment.
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.
- 12.5 kA lightning impulse current (Iimp).
- 20 kA nominal discharge current (In).
- 50 kA maximum discharge current (Imax).
- Three-pole 3+0 protection configuration.
- Visual Green (OK) / Not Green (Replace) status indication.
- Integrated remote indication microswitch.
- Pluggable DIN rail mounted format.
Reliable Protection Against Electrical Surges
The Mersen K1-3P320-M diverts high-energy surge currents away from connected equipment before damaging overvoltages can reach critical components. This helps reduce the risk of failures in switchgear, motor drives, automation controls, power supplies and other sensitive electrical systems.
Its combined lightning-current and surge protection, remote monitoring capability and replaceable modules make it particularly suitable for installations where system availability and straightforward preventative maintenance are important.
Typical Applications
- Main three-phase electrical distribution boards.
- Industrial automation and control panels.
- Manufacturing and processing facilities.
- Commercial and institutional buildings.
- Data centres and telecommunications facilities.
- Water and wastewater treatment installations.
- Infrastructure and utility systems.
- 277/480 V AC three-phase TNC power networks.
Technical Specifications
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| Impulse Current Iimp (kA) | 12.5 kA | |
|---|---|---|
| SPD Type | Type 1+2 | |
| Voltage | 480 V | |
| Phase | Three Phase | |
| Poles | 3-pole | |
| Device Type | Surge protection device | |
| Earthing System | TN-C | |
| Nominal Discharge Current (In) | 20 kA | |
| Remote Signal | Yes | |
| Manufacturer | Mersen | |
| Series | Surge-Trap® K - K1 Series | |
| Model | K1-3P320-M | |
| Part number | 44120305 | |
| EAN | 8435297888178 | |
| 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 | |
| Nominal operating voltage (Un) | 277/480 V AC | |
| Lightning impulse current (Iimp) | 12.5 kA | |
| Nominal Discharge Current (In) | 20 kA | |
| Maximum discharge current (Imax) | 50 kA | |
| Rated short-circuit withstand capability | 25 kA | |
| Configuration | TN-C | |
| Number of poles | 3 | |
| Protection modes | L-PE (N) | |
| System compatibility | TN-C | |
| Mounting type | DIN rail | |
| Format | Pluggable | |
| Status indication | Green (OK) / Not Green (Replace) | |
| Remote indication | Integrated microswitch | |
| Remote contact capacity | 250 V AC / 0.5 A; 30 V DC / 1 A | |
| Protection rating | IP20 | |
| Operating temperature | -40 to +85°C | |
| Maximum operating altitude | 4,000 m | |
| Tightening torque | 3 N m | |
| Dimensions (H × W × D) | Approx. 90 × 72 × 98 mm | |
| Weight | Approx. 0.52 kg | |
| RoHS compliant | Yes |
Frequently Asked Questions
What is the Mersen 44120305 K1-3P320-M used for?
It provides Type 1+2 protection for three-phase electrical installations against lightning currents, switching transients and other temporary surge events.
Does the K1-3P320-M include remote monitoring?
Yes. The device includes an integrated microswitch that can remotely indicate whether the surge protection modules remain operational or require replacement.
Which electrical systems is this SPD suitable for?
The K1-3P320-M is designed for three-phase TNC systems with a nominal operating voltage of 277/480 V AC.
What surge current ratings does this device provide?
It has a lightning impulse current rating of 12.5 kA, a nominal discharge current of 20 kA and a maximum discharge current of 50 kA.
How is the Mersen 44120305 installed?
The unit mounts onto a standard DIN rail inside an electrical distribution board. Its pluggable modules can be replaced without removing the complete base assembly.
Trusted Protection for Three-Phase Electrical Systems
Mersen Surge-Trap® K Series surge protection devices are specified by electrical engineers and panel builders for dependable protection of industrial, commercial and infrastructure power distribution systems.
