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Mersen Surge Protector Type 1+2 SPD 4 Pole 277/480 Volt 20KA TNS
Mersen STPT12-12K320V-4P Type 1+2 surge protection device with 12.5 kA lightning impulse current rating and 320 V UC for 277/480 V AC three-phase plus neutral TNS systems.
This product has been discontinued
A direct replacement is available below.
Replacement product
K1-4P320 Mersen Surge Protector Type 1+2 SPD 4 Pole 277/480 Volt 20KA TNS
SKU: 44120412
£264.86 ex VAT
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Why Choose the Mersen 83120146 STPT12-12K320V-4P Surge Protection Device?
The Mersen 83120146 STPT12-12K320V-4P is a high-performance Type 1+2 Surge Protection Device (SPD) designed to protect low-voltage electrical installations from lightning currents and transient overvoltages. Developed for industrial, commercial and infrastructure environments, it helps protect distribution systems, control panels and sensitive electrical equipment from damaging surge events.
Part of the trusted Mersen Surge-Trap® STPT12 Series, this pluggable DIN rail mounted surge protection device combines lightning current discharge capability with transient overvoltage protection in a compact modular design. It is suitable as a first stage of protection in main distribution boards and incoming power supply panels.
Designed for 277/480 V AC three-phase plus neutral (3Ph+N) electrical systems in a 4+0 TNS configuration, the STPT12-12K320V-4P provides a 12.5 kA Iimp (10/350 μs) lightning impulse current rating per pole. Its 320 V UC maximum continuous operating voltage makes it suitable for higher voltage three-phase installations requiring dependable surge protection.
Key Advantages
- Combined Type 1+2 surge protection for lightning currents and transient overvoltages.
- 12.5 kA Iimp (10/350 μs) lightning impulse current capability.
- Designed for 277/480 V AC three-phase plus neutral TNS systems.
- 4-pole pluggable modular design for easier maintenance.
- 320 V UC maximum continuous operating voltage.
- DIN rail mounting for straightforward installation in electrical panels.
- Suitable as primary surge protection in incoming power distribution boards.
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.
- 277/480 V AC nominal operating voltage.
- 320 V UC maximum continuous operating voltage.
- Designed for 3Ph+N, 4+0 TNS electrical systems.
- 4-pole, 4-module pluggable format.
- DIN rail mounted installation.
Reliable Protection Against Lightning and Voltage Surges
Surge protection devices help reduce the risk of equipment damage caused by lightning strikes, utility switching and transient overvoltage events. Installing a Type 1+2 SPD at the main distribution board provides a robust first line of defence for the wider electrical installation.
The Mersen STPT12 series is engineered for demanding electrical environments, offering dependable surge protection for switchboards, automation systems, industrial machinery and building services where operational continuity is essential.
Typical Applications
- Main electrical distribution boards.
- Industrial control panels.
- Commercial building electrical systems.
- Manufacturing facilities.
- Infrastructure and utility installations.
- Automation equipment and switchboards.
Technical Specifications
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| Impulse Current Iimp (kA) | 12.5 kA | |
|---|---|---|
| Voltage | 480 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 | STPT12-12K320V-4P | |
| Part number | 83120146 | |
| Product type | Type 1+2 Surge Protection Device | |
| IEC classification | Class I+II | |
| Nominal operating voltage (Un) | 277/480 V AC | |
| Maximum continuous operating voltage (Uc) | 320 V AC | |
| System configuration | TN-S | |
| Lightning impulse current (Iimp) | 12.5 kA (10/350 μs) | |
| Number of poles | 4 | |
| Number of modules | 4 | |
| Mounting type | DIN rail | |
| Format | Pluggable | |
| Standards | EN 61643-11 / IEC 61643-11 | |
| RoHS compliant | Yes | |
| HS Code | 85363090 | |
| Country of Manufacture | Spain |
Frequently Asked Questions
What is the Mersen 83120146 used for?
It is used to protect low-voltage electrical installations against lightning currents and transient overvoltages.
What type of surge protection device is this?
The 83120146 is a Type 1+2 / Class I+II surge protection device designed for lightning current discharge and transient overvoltage protection.
What electrical system is this device designed for?
It is designed for 277/480 V AC three-phase plus neutral (3Ph+N) systems using a 4+0 TNS configuration.
What does the 320 V UC rating mean?
The 320 V UC rating refers to the maximum continuous operating voltage that the surge protection device can withstand during normal operation.
Where should this SPD be installed?
It is typically installed in the main incoming distribution board as the first stage of surge protection for the electrical installation.
Trusted for Industrial Electrical Protection
Mersen Surge-Trap® surge protection devices are trusted by electrical engineers, panel builders and industrial facilities worldwide to provide dependable protection against lightning currents, switching surges and transient overvoltages.
