LSP provides Type 1 SPD (Surge Protector Device) solutions for low-voltage power systems, designed for installation at the main service entrance where lightning-induced surge currents enter the system.
Our designs focus on long-term thermal stability, reliable follow-current extinction, and mechanical integrity under high-energy impulse conditions – key factors that determine whether a Type 1 Surge Protection Device can perform predictably throughout its service life.
All solutions comply with IEC 61643-11 and are supported by coordinated protection guidance and application-level technical support for EPCs, OEMs, and system integrators worldwide.
Type 1
First-stage lightning current protection
10/350 μs
Service Entrance
High-Energy Design
Type 1 SPD (Surge Protector Device) – Handles indirect lightning currents (Iimp 10/350 µs), up to 25 kA at the main service entrance. Universal Compatibility – Works with TN‑S, TN‑C, and TT systems. Reliable & Certified – IEC/EN 61643‑11 certified, engineered for long-term stability.
Type 1 SPD (Surge Protector Device) is installed at the main service entrance of an electrical system and is designed to handle high-energy surges from indirect lightning strikes, providing protection against severe transient events for equipment and circuits within the system.
Type 1 SPD (Surge Protector Device) is a high-energy surge protective device for low-voltage AC systems.
It is installed at the main service entrance as the primary stage of protection.
The device is designed to withstand high-current surges from lightning strikes and line transients.
It intercepts high-energy surge currents, reducing the impact on downstream equipment and loads. This ensures reliable system operation.
| Parameter | FLP25-275 | Engineering Significance |
| Iimp | 25 kA | Surge current withstand at 10/350 µs waveform |
| In | 25 kA | Capability to repeatedly discharge multiple surges |
| Imax | 100 kA | Peak discharge current capability |
| Up | 1.5 kV | Residual voltage across SPD after surge discharge |
According to IEC/EN 61643‑11, Type 1 SPD (Surge Protector Device) is a Class I device (equivalent to Class B in German standards).
It must pass 10/350 µs lightning impulse testing to demonstrate high-energy surge withstand capability.
This class indicates it can handle large-magnitude surge currents and serves as the primary unit in a coordinated surge protection system.
LSP’s Type 1 SPD (Surge Protector Device) FLP25 series is specifically designed for the main service entrance of low-voltage power systems. It features robust MOV/GDT components and an engineered internal structure and has undergone rigorous testing. Suitable for installation at LPZ 0/1 boundaries, it provides predictable and reliable protection, effectively handling high-energy surges and direct lightning currents.
FLP25 series Type 1 SPDs are installed at the main service entrance at the LPZ 0/1 boundary, providing system-level surge protection for low-voltage power distribution. They mitigate high-energy surges and transient overvoltages across residential, commercial, industrial, energy storage, data center, wastewater treatment, and EV charging applications.
The performance verification of Type 1 SPD (Surge Protector) focuses on their ability to withstand 10/350 µs lightning currents and high-energy impulses. Performance is verified through standardized lightning impulse, current handling, and safety tests in accordance with IEC 61643‑11 / EN 61643‑11 standards, confirming stability, reliability, and controlled failure behavior when installed at the LPZ 0/1 boundary as front-line protection.
LSP’s Type 1 SPD (Surge Protector Device) is designed and tested according to IEC/EN 61643‑11. Certified by TÜV, CE, and CB, compliant with ISO 9001 quality management. Suitable for first-line protection at the main service entrance of low-voltage power systems at LPZ 0/1 boundaries. Ensures safe and reliable system operation under high-energy lightning surges.
LSP production facilities use automated equipment and perform electrical testing on critical components, with housings and metal parts manufactured using high-precision molding and stamping. Finished Type 1 SPDs (Surge Protectors) undergo systematic quality control to ensure predictable performance in critical low-voltage power systems.
Type 1 SPDs (Surge Protector) must be installed according to electrical standards. They are connected in parallel ahead of the main distribution panel or circuit breaker, with wiring following standard diagrams and remote signaling terminals. This ensures front-line protection at the LPZ 0/1 boundary.
The following field feedback summarizes real-world applications of Type 1 SPD (Surge Protector) in low-voltage power distribution systems. The comments are provided by engineers involved in installation, operation, and maintenance across residential, industrial, infrastructure, and EV charging projects. They focus on the performance of Type 1 SPD (Surge Protector Devices) at the main service entrance, including operational continuity, reduced surge-related disturbances, and maintenance practicality.
A Type 1 SPD (Surge Protector) is designed to handle high-energy surges caused by direct lightning currents or severe transient events. In engineering practice, it is installed at the origin of the electrical installation, typically at the main distribution board (MDB), to prevent lightning current from entering downstream power systems.
Type 1 SPDs are applied before the main breaker and are tested with a 10/350 µs waveform, representing direct lightning currents.
Type 2 SPDs are installed downstream of the main breaker and are tested with an 8/20 µs waveform, addressing residual surges caused by switching operations or indirect lightning effects.
In most projects, engineers prefer to install a Type 1 SPD as close as possible to the main incoming supply to minimize residual voltage and ensure predictable protection.
For effective operation, Type 1 SPDs (Surge Protector) are installed before the main breaker and coordinated with a suitable backup protective device (MCCB/MCB or fuse).
Keeping the total connection length (L + N + PE) within 0.5 m is critical to limit inductive voltage rise during lightning current discharge.
Type 1 SPDs (Surge Protector) are defined by their ability to withstand a 10/350 µs lightning current waveform. Engineers typically focus on the impulse current rating (Iimp), which indicates how much lightning current the device can safely discharge without loss of function.
Type 1 SPDs (Surge Protector) are commonly applied in installations exposed to high lightning risk, including:
Yes. Type 1 SPDs are available for both single-phase and three-phase networks. In practice, three-phase configurations are more common in industrial and commercial systems, while single-phase units are used in smaller or decentralized installations.
While Type 1 SPDs (Surge Protector Device) are most commonly applied in AC power systems, dedicated versions are also used in DC applications, such as large photovoltaic systems or DC distribution networks. The selection is based on system voltage, polarity, and grounding concept.
LSP's Type 1 SPDs combine high-energy discharge capability with stable electrical characteristics. The use of MOVs for line protection, GDTs for N-PE paths, and compliance with IEC/EN 61643-11 testing ensures consistent performance under repeated lightning stress.
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