Surge protectors and lightning arrester is not the same thing. Although both have the function of preventing overvoltage, especially preventing lightning overvoltage, there are still many differences in application.

1. The rated voltage of the arrester is from ﹤3kV to 1000kV, and the low voltage is 0.28kV and 0.5kV. The rated voltage of the surge protective device is ≦1.2kV, 380, 220~10V~5V.

2. Surge arrester is generally installed on the primary system to prevent the direct intrusion of lightning waves and protect overhead lines and electrical equipment; while SPD surge protective devices are mostly installed on the secondary system after the arrester eliminates the direct intrusion of lightning waves, or the arrester There are no supplementary measures to eliminate the lightning waves; therefore, the arrester is mostly installed at the incoming line; the SPD is mostly installed at the end of the outgoing line or at the signal circuit.

3. The arrester is to protect electrical equipment, and the surge protector is mostly to protect electronic instruments or instruments;

4. Because the lightning arrester is connected to the electrical primary system, it must have sufficient external insulation performance, and the appearance size is relatively large, and the surge protector can be made small due to the low voltage.

5. The withstand voltage level of electrical equipment and electronic equipment is not on the same order of magnitude, and the residual voltage of the overvoltage protection device should match the withstand voltage level of the protected object.

6. Surge arrester is mainly used in power stations, lines, distribution stations, power generation, capacitors, motors, transformers, iron and steel smelting, and railways. Surge protectors are mainly used in low-voltage power distribution, cabinets, low-voltage electrical appliances, communications, signals, machine stations, and machine rooms.

7. Technically speaking, the arrester does not reach the level of the surge protector in terms of response time, pressure limiting effect, comprehensive protection effect, and anti-aging characteristics.

What is a Surge Protector?

A surge protector is a protective device used to prevent transient voltage surges from damaging electrical equipment. It can detect abnormal voltage peaks in the system and quickly divert excess energy to the ground, thereby preventing voltage surges from causing damage to sensitive equipment.

What is a Lightning Arrester?

A lightning arrester is a device used to protect buildings, power systems, and equipment from direct lightning strikes and induced lightning damage. By directing the lightning current directly to the ground, the lightning arrester effectively prevents high-voltage lightning strikes from causing serious damage to equipment or buildings, thus becoming the first line of defense against lightning strikes.

Functional Analysis: Suppressing Surges vs. Diverting Lightning

Surge protector: Specifically used to suppress surge voltages generated internally in the system (such as transient overvoltages caused by power grid fluctuations, load switching, equipment startup, etc.), by directing excess current to the ground to prevent damage to electrical equipment.

Lightning arrester: Mainly used for diverting lightning strikes, preventing the huge energy impact caused when lightning directly hits buildings or power systems. The lightning arrester provides a low impedance path to divert the lightning current into the ground, thereby avoiding equipment and structural damage.

Installation Location: Internal vs External

Surge protector: usually installed internally in the power system, such as distribution boards, terminal equipment, photovoltaic combiner boxes, etc., to provide protection for the equipment. Surge arresters are generally installed at the power inlet of the system or at the front end of equipment to mainly prevent voltage surges within the system.

Lightning arrester: typically installed externally in the system, especially on building roofs, communication base station antennas, external transmission lines, etc., to prevent external lightning strikes from causing harm to the system. The installation position of lightning arresters ensures that they can preferentially guide lightning currents into the ground.

Voltage Withstand Capability: Dealing with Internal Surges vs. Direct Lightning Strikes

Surge protector: designed to withstand and dissipate low to moderate intensity voltage surges, typically transient voltages ranging from several kilovolts to tens of kilovolts. Its goal is to protect equipment from overvoltages generated by grid disturbances, equipment switches or load switching.

Lightning arrester: able to withstand extremely high voltages and currents, generally designed for strong voltages and currents caused by lightning strikes, with voltages typically reaching hundreds of kilovolts or higher. Its main task is to protect buildings, power systems and equipment from the effects of lightning direct current.

Choose the Right Surge Protector and Lightning Arrester to Fully Protect the Electrical System

To provide comprehensive electrical protection for the system, it is necessary to consider system requirements, potential risks, and environmental conditions comprehensively and make wise equipment choices.

High-risk Areas should Prioritize the Installation of Lightning Arresters:

- In high lightning strike risk areas (such as communication towers, power lines, substations, etc.), lightning arrester should be installed at the entrance end of buildings or systems to safely guide the lightning current into the ground.

- For photovoltaic systems or wind farms, lightning arrester should be added to the input end of combiner boxes or inverters to prevent huge impacts from lightning on the system.

Internal Surge Protection must be Installed with Surge Protector:

- Install surge protector at the front end of distribution cabinets, branch circuits, and terminal equipment to effectively suppress transient voltage surges within the system.

- In photovoltaic systems, industrial automation equipment, and communication systems, surge protector can prevent damage to equipment from surge voltages and increase the service life of the equipment.

Forming a multi-level protection barrier through the combination of “lightning arrester + surge protector”.

- Level 1 protection: Use lightning arrester at the main distribution cabinet or system entrance to guide lightning current into the ground.

- Level 2 protection: Install surge arresters in distribution boxes or branch lines to suppress residual surges.

- Level 3 protection: Install fine surge arresters at terminal equipment to prevent residual voltage from damaging sensitive devices.

Can surge protector replace lightning arrester?

The working mechanism and application scenarios of the two are completely different, so they cannot be substituted for each other.

Surge protector function: Mainly used to suppress surges in the system, such as transient overvoltages caused by motor starting, load switching, or power grid fluctuations. It absorbs and guides excess voltage to maintain it at a safe level, thus protecting terminal equipment from surge damage.

Lightning arrester function: Specifically designed to prevent direct lightning strikes or induced lightning strikes, quickly diverting huge lightning currents into the ground to prevent high-voltage currents from entering the power system and protecting buildings and electrical equipment from damage caused by lightning strikes.

Surge protector cannot handle high voltage and current shocks caused by lightning strikes; the energy of a lightning strike far exceeds the capacity of a surge protector.

While lightning arrester can prevent intrusion of lightning strikes, they cannot suppress surges within the system; therefore, they cannot replace the function of surge protector.