Top AC Surge Protector Manufacturer in China Setting the Standard for Reliability and Innovation At LSP, we design AC Surge Protector Devices with one purpose: uncompromising protection for your critical systems. Built on strict IEC/EN 61643-11 standards and modular architecture compatible with 3+1 and 4+0 configurations , our solutions ensure seamless integration wherever protection is needed. Using premium components from global leaders such as Phoenix Contact—featuring MOV and GDT technologies—our portfolio spans Type 1 SPDs , Type 2 SPDs , and Type 3 SPDs , delivering certified surge protection for every application, from renewable energy and telecom to industrial automation. LSP ensures long-term reliability while maintaining flexibility and compliance with international standards. How to Choose an AC Surge Protector Choosing an AC Surge Protector shouldn’t be a headache. It’s simply about matching your site’s risks to your equipment’s needs. We’ve simplified the technical details below to help you pinpoint the exact configuration for a safe, compliant, and reliable system. Quick Selection Guide for AC Surge Protectors Not sure if you need Type 1 or Type 2? Let our team confirm based on your building’s risk profile. AC Surge Protector Model Selection Rules FLP25-275/2(s) , FLP25-275/1(s)+1 FLP25-275/4(s) , FLP25-275/3(s)+1 FLP25-275/1(s) , FLP25-275/1(s)+1 LPZ 0A/0B → LPZ 2 FLP12,5-275/2(s) , FLP12,5-275/1(s)+1 FLP12,5-275/4(s) , FLP12,5-275/3(s)+1 FLP12,5-275/1(s) , FLP12,5-275/1(s)+1 LPZ 0A/0B → LPZ 2 FLP7-275/2(s) , FLP7-275/1(s)+1 FLP7-275/4(s) , FLP7-275/3(s)+1 FLP7-275/1(s) , FLP7-275/1(s)+1 SLP40-275/2(s) , SLP40-275/1(s)+1 SLP40-275/4(s) , SLP40-275/3(s)+1 SLP40-275/1(s) , SLP40-275/1(s)+1 SLP20-275/2(s) , SLP20-275/1(s)+1 SLP20-275/4(s) , SLP20-275/3(s)+1 SLP20-275/1(s) , SLP20-275/1(s)+1 Provide your system voltage and pole configuration to receive the specific part numbers for your project. Our AC Surge Protector Series Maximize Protection and Reliability for Your Electrical Systems As one of the best surge protector brands, LSP ensures unmatched protection and reliability, safeguarding your electrical systems with superior performance. Certified with 8/20 waveform and 10/350 waveform tests, our SPD endures In = 20kA (±5 times) and Imax = 40kA (±1 time), ensuring it performs excellently under both lightning and switching surges, offering complete protection to your electrical systems. Unlike traditional SPDs with basic moisture protection, our MOV encapsulation design prevents moisture infiltration, reducing failure risks and extending lifespan in humid environments, ensuring stable performance. Our SPD features an internally developed tripping mechanism that isolates and extinguishes arcs , preventing fires and ensuring safe disconnection even under extreme lightning conditions, providing maximum safety for your equipment. Our Surge Protection Device uses reinforced metal contacts (8 mm × 0.8 mm ). This robust design enhances conduction and strength, enabling the device to withstand high surges while ensuring stable, long-term protection for connected equipment. Innovative Design and Advanced Safety Features Benefit from high-precision AC surge protector with robust durability. Features such as fast response mechanisms, optimized clamping voltage, and advanced MOV/GDT components safely redirect surges, extending the lifespan of sensitive equipment while maintaining consistent performance. We use high-quality MOVs from LKD and GDTs from Vactech to ensure the stability and lightning protection performance of our AC surge protectors. Robust metal lead pins (0.8 mm thick, 8 mm wide) withstand high electrical potentials without breaking. Our R&D team’s optimized low-temperature trip mechanism and advanced soldering process enhance arc suppression and fire prevention. Every AC surge protector undergoes rigorous testing; only devices meeting our standards are approved. All AC Surge Protectors are TUV, CB, and CE certified. Our Continuous SPDs Improvement As AC SPD suppliers in China, we continually advance our technology to meet diverse lightning protection needs and deliver the best surge protectors to our customers. Why Choose LSP As Your Surge Protection Supplier? Professional Manufacturing Our manufacturing processes strictly adhere to ISO9001, ensuring compliance and efficiency. Our surge protectors are fully certified with TUV, CB, and CE, guaranteeing superior quality and suitability for global markets. Innovative R&D Strength In the electrical field, we have independent R&D capabilities. Our R&D team, with 20 years of experience, provides technical support to help you realize your technical visions. Rigorous Quality Control Our quality control system integrates advanced testing procedures, including lightning impulse tests and multiple durability evaluations, to ensure SPD reliability under surges, heat, corrosion, and fire risks. Consistency checks on solder durability and unified welding temperatures further guarantee long-term stability and safety. Comprehensive Marketing Support We offer more to our valued customers! Including high-quality corrugated cardboard packaging, 3D animation materials for marketing, and regulatory and certification support. Assured Product Guarantee We also provide 7-day return and 30-day exchange policy. Shipping costs and duties are covered by us during the warranty period.

Reliable Fast Delivery Our experienced team manages inventory and production, maintaining a steady stock of materials to handle peak periods. We complete and ship regular orders within 15 days and custom orders within 30 days, maintaining a 96% on-time rate! The Trusted Partner for Businesses Seeking Certified AC Surge Protector Device Comprehensive AC Surge Protector Solutions for Multiple Industries Our AC surge protector solutions serve diverse sectors: datacenters, LED systems, security systems, industrial installations, wind turbines, domestic and industrial photovoltaics, solar farms, energy storage, and water treatment facilities. As surge protector suppliers, we empower multiple industries with customized protection and proven expertise. Domestic/Off-grid Photovoltaic Industry Photovoltaic Energy Storage Systems Wind Turbine Installation Water Treatment Security Systems Radiocommunication What Our Customers Say about LSP's AC Surge Protector FAQ About AC Surge Protector What is an AC surge protector and why is it necessary? An AC Surge Protector (or SPD) is a safety device designed to limit transient overvoltages and divert surge currents away from sensitive equipment. It is necessary because even minor power surges caused by lightning or grid switching can degrade electronic components over time, leading to premature failure, data loss, and costly downtime. What is the difference between Type 1, Type 2, and Type 3 AC surge protectors? The types are defined by their installation location and the level of energy they can handle: Type 1: Installed at the main service entrance to protect against direct lightning strikes (10/350 μs waveform). Type 2: Installed at sub-distribution boards to protect against indirect lightning and switching surges (8/20 μs waveform). Type 3: Installed close to terminal equipment (e.g., PLCs, PCs) for “fine” protection against residual overvoltages. How do I choose the right AC surge protector for my electrical system? To select the correct AC Surge Protector, you must consider four key factors: Installation location: Determine whether the SPD is at the main service entrance (Type 1 / Type 1+2), at a distribution board (Type 2), or near sensitive equipment (Type 3 / Type 2+3). This is what selects the type. Supply system: Identify if your network is TN, TT, or IT. Surge risk: Evaluate the lightning risk and whether the building has an external lightning rod (requires Type 1). Voltage protection level (Up): Ensure the SPD’s Up is lower than the impulse withstand voltage of your equipment. How do I choose the correct Uc (Max. Continuous Operating Voltage) rating? The Uc rating of an AC Surge Protector must be higher than the maximum possible voltage of your power grid, including potential fluctuations. For a standard 230V AC system, a Uc of 275V or higher is typically recommended to prevent the SPD from activating under normal voltage swells, which would shorten its lifespan. When should I use a Type 1+2 AC surge protector instead of a standalone Type 2? A Type 1+2 AC Surge Protector is ideal for compact distribution boards where space is limited but high-energy protection is still required. It is recommended for buildings with an external lightning protection system or those fed by overhead lines, as it handles both direct lightning currents and induced surges in a single coordinated module. Does an AC surge protector need backup overcurrent protection? Yes. Every AC Surge Protector should be installed with a dedicated SSD (SPD-specific protection device, formerly referred to as SCB) upstream, unless the existing upstream protection is already below the manufacturer’s specified maximum value. The SSD ensures the SPD is safely disconnected from the grid in the event of a short circuit or thermal end-of-life condition. SSD is selected to match the SPD rating and the short-circuit capacity of the installation. Where should an AC surge protector be installed for maximum effectiveness? For the best results, the AC Surge Protector should be installed as close as possible to the point of entry or the equipment being protected. The lead wires (connecting cables) must be kept as short as possible (ideally under 0.5 meters) to minimize inductive voltage drops, which can significantly reduce the SPD’s actual protection level. How do I know when an AC surge protector needs to be replaced? LSP AC Surge Protectors feature a visual status window. A Green window indicates the device is functional, while a Red window means the internal components have degraded and the module must be replaced. For critical systems, we also recommend using SPDs with remote signaling to alert maintenance teams immediately upon failure. Can I use an AC surge protector on a DC system? No. AC surge protectors are designed, tested, and certified to IEC/EN 61643-11 for AC systems. DC circuits have no natural zero crossing, so the arc-extinguishing and follow-current behaviors are different. Using an AC SPD on a DC circuit can fail to protect and may be unsafe. For DC systems, use a dedicated DC surge protector that is tested to the appropriate DC standard. Which AC surge protector fits a TT, TN-S, TN-C, TN-C-S, or IT system? The selection depends on your earthing system, because the earthing system determines the SPD’s pole configuration and how the N–PE path is protected. The table below shows the typical configuration for LSP’s SLP40-275 Type 2 series across the five most common systems: In short: for an IT system, only three-pole devices (3+0) are used because the IT system has no neutral conductor — only three phase lines, each protected to PE. For the other systems, the “+1” suffix indicates that the neutral-to-PE path is protected by a dedicated GDT stage rather than a MOV, which is the recommended pattern when the N–PE link is exposed or when the system requires spark-gap behavior on the neutral. AC Surge Protector (AC SPD): A Complete Guide to Types, Selection, and Applications Table of Contents What Is an AC Surge Protector? (A Simple Explanation) An AC surge protector does the same job for your electrical system. In normal conditions it sits quietly and lets power flow through. When a surge arrives, it opens a low-resistance path that diverts the excess voltage to ground, protecting the equipment connected downstream. When the surge passes, it returns to its high-resistance state. A simple way to understand it: an AC surge protector works like a pressure relief valve on a water pipe. AC Surge Protector Definition and Working Principle What Is an AC Surge Protector Made Of? Metal oxide varistor (MOV). This is the core protection element. A MOV is composed of non-linear zinc oxide grains embedded in a ceramic matrix, connected between metal electrodes. Its resistance drops sharply when the voltage across it exceeds a threshold, allowing it to conduct the surge current and limit the voltage. In surge protectors, MOVs are typically square-shaped for Type 1 and Type 2 designs (where they handle higher energy), and disc-shaped for Type 3 and signal SPDs (where the energy class is lower). MOV vs Gas Discharge Tube (GDT) vs Graphite Spark Gap: Key Differences Three core protection technologies appear in low-voltage AC surge protectors: the metal oxide varistor (MOV), the gas discharge tube (GDT), and the graphite spark gap. In modern designs they are usually complementary, each handling a different part of the surge problem. In IEC/EN 61643-11, an SPD built around one of these is classified as voltage-limiting, voltage-switching, or combination type. AC Surge Protector Installation and Maintenance Ensure Business Continuity, Safeguard Your Equipment Surge Protective Device AC Surge Protector DC Surge Protector Signal Surge Protector PV Combiner box Automatic Transfer Switch Domestic/ Off-grid Photovoltaic Industry Photovoltaic Energy Storage Systems Wind Turbiner Installation Material Matters Quality Control OEM Partnerships Package & Deliver Wenzhou Arrester Electric Co., Ltd. 5th FL, Bldg 2, No. 888 Liujiang Road, Beibaixiang, Yueqing, Zhejiang 325603 China info@lsp.global +86-18968826885 +86-18968826885 Copyright © 2010-2026 Wenzhou Arrester Electric Co., Ltd. All Rights Reserved. Get A Quote Now