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Mersen Surge Protector Type 2 SPD 3 Pole 400/690 Volt 20KA IT
Mersen STPT2-40K440V-3P Type 2 surge protection device with 40 kA Imax, 400 / 690 V AC nominal operating voltage, 440 V AC maximum continuous operating voltage, 3+0 IT / TNC configuration and pluggable DIN rail design.
This product has been discontinued
A direct replacement is available below.
Replacement product
K2-3P440 Mersen Surge Protector Type 2 SPD 3 Pole 400/690 Volt 20KA IT
SKU: 44020308
£84.12 ex VAT
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Why Choose the Mersen STPT2-40K440V-3P Surge Protection Device?
The Mersen STPT2-40K440V-3P (Part Number 83020142) is a high-performance Type 2 surge protection device (SPD) designed to protect three-phase low-voltage electrical installations against transient overvoltages caused by lightning activity and electrical switching events. As part of the Mersen Surge-Trap® Pluggable STPT2 Series, it provides dependable protection for industrial, commercial and infrastructure electrical systems.
Featuring a 40 kA maximum discharge current (Imax), 440 V AC maximum continuous operating voltage (Uc) and pluggable modular construction, this SPD supports straightforward installation, rapid cartridge replacement and reliable long-term protection in electrical distribution panels.
Designed for 400 / 690 V AC three-phase systems with a 3+0 IT / TNC configuration, the STPT2-40K440V-3P is well suited to protecting automation equipment, machine control panels, commercial switchboards, building services and critical low-voltage electrical installations.
Key Advantages
- Reliable Type 2 surge protection device for three-phase low-voltage systems.
- 40 kA maximum discharge current for effective transient overvoltage protection.
- 440 V AC maximum continuous operating voltage for higher voltage installations.
- Pluggable cartridge design simplifies replacement and maintenance.
- Compact 3-pole DIN rail mounting format for distribution boards and control panels.
- Suitable for IT and TNC network configurations.
Key Features
- Mersen Surge-Trap® Pluggable STPT2 Series.
- Type 2 / Class II surge protection device.
- 40 kA Imax maximum discharge current using 8/20 μs waveform.
- 20 kA nominal discharge current (In).
- 400 / 690 V AC nominal operating voltage.
- 440 V AC maximum continuous operating voltage (Uc).
- Three-phase, 3+0 IT / TNC configuration.
- 3-pole, 3-module pluggable construction.
- Visual indication system for device status.
- DIN rail mounting for electrical panels.
Reliable Surge Protection for Three-Phase Installations
Type 2 surge protection devices are installed within electrical distribution systems to help limit transient overvoltages before they reach sensitive connected equipment. This helps reduce equipment damage, minimise downtime and improve the reliability of critical electrical systems.
The Mersen STPT2 pluggable range combines high discharge capability with replaceable cartridges and clear device status indication, making it suitable for preventative maintenance in control panels, low-voltage switchgear and commercial distribution boards.
Typical Applications
- Three-phase electrical distribution boards.
- Industrial automation systems.
- Machine control panels.
- Commercial switchboards.
- Building management systems.
- Telecommunications and data infrastructure.
- Water treatment facilities.
- Low-voltage installations requiring 400 / 690 V AC surge protection.
Technical Specifications
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| Voltage | 690 V | |
|---|---|---|
| Phase | Three Phase | |
| Poles | 3-pole | |
| Device Type | Surge protection device | |
| SPD Type | Type 2 | |
| Earthing System | IT, TN-C | |
| Nominal Discharge Current (In) | 20 kA | |
| Remote Signal | No | |
| Manufacturer | Mersen | |
| Series | Surge-Trap® Pluggable STPT2 Series - 40kA | |
| Model | STPT2-40K440V-3P | |
| Item number | 83020142 | |
| Product type | Surge protection device | |
| SPD Type | Type 2 / Class II | |
| UL SPD type | Type 2 Component Assembly | |
| Maximum discharge current | 40 kA Imax (8/20 μs) | |
| Nominal discharge current | 20 kA In (8/20 μs) | |
| Nominal operating voltage | 400 / 690 V AC | |
| Maximum continuous operating voltage | 440 V AC | |
| System configuration | TN-C (also suitable for 400 V IT) | |
| Number of poles | 3 poles | |
| Module width | 3 modules | |
| Format | Pluggable | |
| Mounting type | DIN rail | |
| Protection rating | IP20 | |
| RoHS compliant | Yes | |
| EAN / UPC | 8435297851721 |
Frequently Asked Questions
What is the Mersen STPT2-40K440V-3P used for?
It is used to protect three-phase low-voltage electrical installations and connected equipment against transient overvoltages caused by lightning activity and switching events.
What type of surge protection device is this?
The STPT2-40K440V-3P is a Type 2 / Class II surge protection device for electrical distribution and control systems.
What is the maximum discharge current rating?
This SPD has a 40 kA Imax maximum discharge current rating using an 8/20 μs waveform.
What voltage is this model designed for?
It is designed for 400 / 690 V AC three-phase systems with a 440 V AC maximum continuous operating voltage.
How is this surge protection device installed?
The device is designed for DIN rail mounting and uses a pluggable modular format for straightforward installation and maintenance.
Trusted by Electrical Engineers Worldwide
Mersen Surge-Trap® surge protection devices are trusted by panel builders, electrical contractors and maintenance engineers to protect critical low-voltage installations from damaging transient overvoltages.
