LSP specializes in surge protection solutions for low-voltage power networks, offering a comprehensive range of Type 2 surge protection devices (SPDs) for sub-distribution applications.
Designed for single-phase and three-phase systems, the portfolio supports TT, TN, and IT earthing systems in accordance with IEC 61643-11.
With controlled protection level (Up), reliable 8/20 μs discharge capacity, and long-term thermal stability, LSP Type 2 SPDs ensure dependable protection under repetitive surge conditions.
OEM and project-specific customization enable seamless integration with switchgear systems.
Type 2 / Class II
Type 2 surge protection device for transient overvoltages
8/20 μs Waveform
Distribution Boards
For installation in distribution and sub-distribution boards
Low Protection Level
Voltage protection level (Up), IEC 61643-11
Type 2 surge protection devices are intended for sub-distribution systems, limiting transient overvoltages at the distribution level. In AC networks, they reduce residual surge voltage caused by switching operations or nearby lightning, protecting downstream equipment.
Type 2 SPDs are typically installed in distribution boards or control cabinets, connected in parallel to the busbar system. When coordinated with upstream Type 1 SPDs, they form an effective multi-stage surge protection concept.
Type 2 surge protection devices (SPDs) are designed around dedicated energy-handling components and protective mechanisms to achieve controlled residual-voltage limitation, repeated surge-withstand capability, and stable long-term operation in low-voltage distribution systems.
Type 2 SPDs provide distribution-level transient overvoltage protection and limit residual surge voltage (Up) according to standard 8/20 μs waveforms. They ensure repeated surge capability and coordination with upstream and downstream SPDs. Internal MOVs and GDTs absorb energy and maintain thermal stability, supporting reliable operation under varying conditions.
It is intended for repeated transient events occurring under normal operating conditions, rather than single high-energy lightning impulses.
Within a coordinated protection concept, the Type 2 SPD works together with upstream surge protection devices to control transient stress at the distribution level and reduce surge propagation within the electrical system.
Unlike Type 1 lightning current arresters, Type 2 SPDs are not designed for direct lightning strikes. They are engineered to continuously suppress medium-energy surges, protecting the insulation and dielectric strength of sensitive equipment in the distribution system.
In distribution systems, when a transient overvoltage occurs, the internal MOV (Metal Oxide Varistor) of the Type 2 surge protection device (SPD) transitions from high impedance to low impedance, shunting the surge current to ground. After the surge, the Type 2 SPD returns to its high-impedance state, ready for subsequent events.
This mechanism limits the residual voltage (Up) across downstream circuits, ensuring it remains within the impulse withstand voltage (Uoc) of connected equipment. The Type 2 surge protector provides reliable surge protection type 2 for sensitive devices, preventing insulation stress and potential damage.
2. Add thermal disconnect devices and status indicator modules.
3. Assemble modular units and secure internal bus bars.
4. Close the outer and inner shells, ensuring proper alignment.
5. Mount the assembled SPD onto the DIN rail system.
6. Verify module functionality and overall assembly quality.
The selection of a Type 2 SPD emphasizes long-term surge endurance and residual voltage control rather than single high-energy impulse performance.
| SLP40-275 | Description |
| 20 kA | Rated surge current |
| 40 kA | Maximum surge current |
| ≤ 1.5 kV | Residual voltage at SPD terminals |
| 275 V AC | Maximum continuous operating voltage |
Type 2 SPDs provide transient overvoltage protection at the distribution level. With high-performance MOVs, low-temperature tripping devices, and modular design, Type 2 surge protection devices limit residual voltage (Up) and protect downstream equipment. The design emphasizes repeated transient events, long-term reliability, and system integration, supporting practical applications in distribution circuits.
Feedback comes from site engineers, facility managers, and project leads with experience using Type 2 SPDs. Observations focus on reliable operation, preventing unexpected shutdowns, and overall installation performance.
Yes. Three-phase Type 2 surge protection devices are designed for commercial or industrial installations, providing effective surge diversion and protection for sensitive electrical equipment.
20 kA Type 2 SPDs are designed for residential and small commercial distribution systems, providing effective Type 2 surge protection devices for sensitive appliances and electronics. 40 kA Type 2 SPDs are suitable for high-demand commercial or industrial systems, offering robust Type 2 surge protection for critical equipment and heavier loads.
Yes. Many Type 2 SPD surge protectors feature pluggable modules, allowing fast replacement without rewiring, ensuring uninterrupted type 2 surge protection.
Yes. Type 2 AC surge protection devices and AC SPD Type 2 models are compatible with DIN-rail installations and modular panels, enabling easy integration and maintenance.
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