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Mersen Surge Protector Type 1+2 SPD 4 Pole 230/400 Volt 20KA TNS
Mersen STPT12-12K275V-4P Type 1+2 surge protection device with 12.5 kA lightning impulse current rating for 230/400 V AC three-phase plus neutral systems.
This product has been discontinued
A direct replacement is available below.
Replacement product
K1-4P275 Mersen Surge Protector Type 1+2 SPD 4 Pole 230/400 Volt 20KA TNS
SKU: 44120404
£245.24 ex VAT
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Why Choose the Mersen 83120144 STPT12-12K275V-4P Surge Protection Device?
The Mersen 83120144 STPT12-12K275V-4P is a high-performance Type 1+2 Surge Protection Device (SPD) developed to protect low-voltage electrical installations from lightning currents and transient overvoltages. Designed for industrial, commercial and infrastructure applications, it safeguards critical electrical equipment and power distribution systems against damaging surge events.
Part of the proven Mersen Surge-Trap® STPT12 Series, this pluggable DIN rail mounted surge protection device combines lightning current protection with transient overvoltage suppression in a compact modular design. It is suitable as the first level of protection in main distribution boards where external lightning protection systems are installed.
Designed for 230/400 V AC three-phase plus neutral (3Ph+N) electrical systems in a 4+0 TNS configuration, the STPT12-12K275V-4P delivers a 12.5 kA Iimp (10/350 μs) lightning impulse current rating per pole, providing dependable protection for modern electrical installations.
Key Advantages
- Combined Type 1+2 surge protection for lightning and transient overvoltages.
- 12.5 kA Iimp (10/350 μs) lightning impulse current capability.
- Designed for 230/400 V AC three-phase plus neutral systems.
- 4-pole pluggable modular construction for easy servicing.
- DIN rail mounting for fast installation.
- Suitable as primary surge protection at incoming distribution boards.
- Compact design for industrial electrical panels.
Key Features
- Mersen Surge-Trap® STPT12 Series.
- Type 1+2 / Class I+II surge protection device.
- 12.5 kA Iimp (10/350 μs) lightning impulse current.
- 50 kA Imax (8/20 μs) maximum discharge current.
- 230/400 V AC nominal operating voltage.
- 275 V UC maximum continuous operating voltage.
- 4-pole pluggable module.
- DIN rail mounted installation.
Reliable Protection Against Electrical Surges
Surge protection devices reduce the risk of equipment damage caused by lightning strikes and electrical switching events. Installing a Type 1+2 SPD at the incoming distribution board helps maintain system reliability, minimise downtime and extend the service life of valuable electrical equipment.
The Mersen STPT12 series is widely used in industrial, commercial and infrastructure installations where dependable surge protection is required to maintain operational continuity and protect sensitive electrical systems.
Typical Applications
- Main electrical distribution boards.
- Industrial automation systems.
- Commercial buildings.
- Manufacturing facilities.
- Critical infrastructure.
- Electrical control panels and switchboards.
Technical Specifications
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| Impulse Current Iimp (kA) | 12.5 kA | |
|---|---|---|
| Voltage | 400 V | |
| Phase | Three Phase | |
| Poles | 4-pole | |
| Device Type | Surge protection device | |
| SPD Type | Type 1+2 | |
| Earthing System | TN-S | |
| Nominal Discharge Current (In) | 20 kA | |
| Remote Signal | No | |
| Manufacturer | Mersen | |
| Series | Surge-Trap® STPT12 | |
| Model | STPT12-12K275V-4P | |
| Part number | 83120144 | |
| Product type | Type 1+2 Surge Protection Device | |
| IEC classification | Class I+II | |
| Nominal operating voltage (Un) | 230/400 V AC | |
| Maximum continuous operating voltage (Uc) | 275 V AC | |
| System configuration | TN-S | |
| Lightning impulse current (Iimp) | 12.5 kA (10/350 μs) | |
| Maximum discharge current (Imax) | 50 kA (8/20 μs) | |
| Nominal Discharge Current (In) | 20 kA (8/20 μs) | |
| Number of poles | 4 | |
| Mounting type | DIN rail | |
| Format | Pluggable | |
| Protection rating | IP20 | |
| RoHS compliant | Yes | |
| HS Code | 85363090 | |
| Country of Manufacture | Spain |
Frequently Asked Questions
What is the Mersen 83120144 used for?
It protects low-voltage electrical installations against lightning currents and transient overvoltages.
Where should this surge protection device be installed?
It is normally installed at the incoming distribution board as the primary stage of surge protection.
What electrical system is this SPD designed for?
The device is designed for 230/400 V AC three-phase plus neutral (3Ph+N) TNS electrical systems.
Is this a Type 1 or Type 2 surge protection device?
This product combines both functions and is classified as a Type 1+2 (Class I+II) surge protection device.
How is the device mounted?
The unit is designed for quick installation onto a standard DIN rail within electrical distribution panels.
Trusted for Industrial Surge Protection
Mersen Surge-Trap® surge protection devices are trusted worldwide by electrical engineers, panel builders and industrial facilities to provide dependable protection against lightning and transient overvoltages while helping maximise system uptime.
