Why Choose the Mersen 83120129 Surge Protection Device?
The Mersen 83120129 STPT12-12K150V-3PM 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 industrial, commercial and infrastructure power distribution systems.
This pluggable SPD combines Class I and Class II surge protection in a compact DIN rail mounted format. Its replaceable cartridge design, visual status indication and integrated remote signalling contact make it suitable for applications where quick maintenance, monitoring and long-term system reliability are important.
With a 12.5 kA lightning impulse current rating, 120/208 V nominal operating voltage and 150 V maximum continuous operating voltage, the Mersen 83120129 is ideal for protecting three-phase TNC distribution systems, control panels, automation equipment and sensitive electrical devices 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.
- 150 V maximum continuous operating voltage for 120/208 V systems.
- Integrated remote indication for external SPD status monitoring.
- Pluggable cartridge design supports quick replacement and maintenance.
- Compact 3-pole, 3-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).
- 120/208 V nominal operating voltage.
- 150 V maximum continuous operating voltage.
- 3-pole configuration for 3+0 TNC systems.
- Remote signalling contact for status monitoring.
- 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 TNC electrical systems.
- Industrial automation and control panels.
- Commercial building electrical installations.
- Switchboards, panel building and infrastructure systems.