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Mersen Surge Protector Type 1+2 SPD 4 Pole 230/400 Volt 20KA TT
Mersen STPT12-12K275V-4PG Type 1+2 pluggable surge protection device with 12.5 kA lightning impulse current, 275 V maximum continuous operating voltage, 230/400 V AC nominal voltage, 4 pole 3+1 TT configuration and DIN rail mounting.
This product has been discontinued
A direct replacement is available below.
Replacement product
K1-4PG275 Mersen Surge Protector Type 1+2 SPD 4 Pole 230/400 Volt 20KA TT
SKU: 44120400
£261.18 ex VAT
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Why Choose the Mersen 83120138 Surge Protection Device?
The Mersen 83120138 STPT12-12K275V-4PG is a high-performance Type 1+2 Surge Protection Device (SPD) designed to protect low voltage electrical installations against transient overvoltages caused by lightning activity and switching events. As part of the Mersen Surge-Trap® Pluggable STPT12 Series, it provides reliable first-stage surge protection for three-phase plus neutral TT power distribution systems.
This pluggable SPD combines Class I and Class II surge protection in a compact DIN rail mounted format. Its 3+1 TT configuration provides coordinated protection between live conductors and neutral, with additional protection between neutral and earth, making it suitable for incoming supply panels and installations exposed to atmospheric surges.
With a 12.5 kA lightning impulse current rating, 230/400 V nominal operating voltage and 275 V maximum continuous operating voltage, the Mersen 83120138 is ideal for protecting main distribution boards, switchboards, control panels and sensitive electrical equipment from damaging voltage surges.
Key Advantages
- Combined Type 1+2 surge protection for low voltage installations.
- 12.5 kA lightning impulse current (Iimp) for robust surge handling.
- 275 V maximum continuous operating voltage for 230/400 V systems.
- 3+1 TT configuration for three-phase plus neutral networks.
- Pluggable cartridge design supports fast replacement and maintenance.
- Compact 4-pole, 4-module DIN rail format.
Key Features
- Mersen Surge-Trap® Pluggable STPT12 Series.
- Type 1+2 / Class I+II surge protection device.
- 12.5 kA Iimp (10/350 μs).
- 50 kA maximum discharge current (Imax 8/20 μs).
- 20 kA nominal discharge current (In 8/20 μs).
- 230/400 V nominal operating voltage.
- 275 V maximum continuous operating voltage.
- 4-pole configuration for 3+1 TT systems.
- DIN rail mounted IP20 construction.
Reliable Protection Against Electrical Surges
Surge protection devices help protect electrical systems by safely limiting transient overvoltages before they reach connected equipment. This reduces the risk of damage to switchgear, control systems, drives, PLCs, instrumentation, power supplies and other sensitive electrical components.
The Mersen STPT12 range is designed for use as the first level of protection in main distribution boards and incoming supply panels. Its Type 1+2 classification makes it suitable for installations exposed to atmospheric surges and applications requiring coordinated protection against lightning currents and voltage spikes.
Typical Applications
- Main low voltage distribution boards.
- Incoming power supply panels.
- Three-phase plus neutral TT electrical systems.
- Industrial automation and control panels.
- Commercial building electrical installations.
- Switchboards, panel building and infrastructure systems.
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, TT | |
| Nominal Discharge Current (In) | 20 kA | |
| Remote Signal | No | |
| Manufacturer | Mersen | |
| Series | Surge-Trap® Pluggable STPT12 | |
| Model | STPT12-12K275V-4PG | |
| SKU | 83120138 | |
| Product type | Type 1+2 Surge Protection Device | |
| IEC classification | Class I+II | |
| 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) | |
| Nominal operating voltage (Un) | 230/400 V AC | |
| Maximum continuous operating voltage (Uc) | 275 V | |
| System configuration | TN-S, TT | |
| Network type | TN-S, TT | |
| Protection modes | L-N / N-PE | |
| Number of poles | 4 | |
| Number of modules | 4 | |
| Mounting type | 35 mm DIN rail | |
| Protection rating | IP20 | |
| Format | Pluggable | |
| EAN / UPC code | 8435297851523 |
Frequently Asked Questions
What is the Mersen 83120138 used for?
It is used to protect low voltage electrical installations against transient overvoltages caused by lightning activity and switching events.
What type of surge protection does this device provide?
The Mersen 83120138 provides combined Type 1+2 / Class I+II surge protection.
What electrical system is this SPD designed for?
It is designed for 3 phase plus neutral, 3+1 TT systems operating at 230/400 V AC.
What is the maximum continuous operating voltage?
The device has a 275 V maximum continuous operating voltage, making it suitable for 230/400 V AC systems.
Where is this surge protection device typically installed?
It is typically installed on a DIN rail inside main distribution boards, incoming panels or electrical switchboards.
Trusted for Critical Power Protection
Mersen Surge-Trap® surge protection devices are trusted by electrical engineers, panel builders and industrial facilities worldwide for dependable protection of power distribution systems and sensitive connected equipment.
