How Would You Identify the Lightning Arrester?

When browsing any electrical store online, you'll likely find dozens of products labeled “surge protector.”For consumers outside the electrical industry, it's often difficult to distinguish between these similar-looking protective devices. Today, we'll guide you on how to properly identify lightning arresters.

Understanding SPD Categories: T1, T2, and T3

SPDs are classified into three types based on their functions and installation points. Misidentifying these categories is the most common mistake when selecting surge protection devices:

Key Identification Parameters Beyond Categories

1. Rated Voltage (Uc)

Must match the normal operating voltage of the protected system.

For example, in a home with 220V circuits, you shouldn't select a surge suppressors with a rated voltage below 220V. You may consider YRO's 275V lightning arrester devices for safe margin.

2. Maximum Discharge Current (Imax)

This is the peak lightning or surge current an SPD can safely absorb and divert within a short time.

If an SPD is rated at 40kA, that means it can handle up to 40,000 amperes of surge current instantly without damage.

3. Voltage Protection Level (Up)

The maximum residual voltage present across the SPD terminals during a surge event.

In simpler terms, while the SPD reduces the overvoltage, a portion of the “leak-through” voltage still reaches your equipment (also called residual voltage). This voltage will not exceed the Up value.

For example, an SPD with Up = 1.8kV can limit the voltage seen by your equipment to below 1.8kV during a surge. The lower the Up, the better the protection.

Certifications Are Critical

Third-party certifications like CE, TUV, or UL are important indicators of SPD quality. These aren't just decorations but represent that the product has passed rigorous testing in surge handling capability, fire resistance, and service life.

Take YRO as an example—their lightning arrester devices have obtained CE certification and comply with IEC 61643-11 standards, ensuring they meet international safety and performance requirements.

Replaceable Module Design

High-end SPDS often adopt a plug-in design (modular structure). After a surge occurs, only the internal modules need to be replaced, without the need to replace the entire set of equipment. It is highly suitable for use in solar combiner boxes or industrial control cabinets and is easy to maintain.

YRO's modular SPD supports hot-swapping, helping users quickly restore protection functions and reduce downtime.

Frequently Asked Questions

Can one surge suppressors protect the whole house?

While a T1 surge arrester device installed at the main panel provides the first line of defense, comprehensive protection requires a layered approach. T1 alone may not fully protect sensitive electronics—T2 or T3 devices should also be installed at the load points. This ensures the surge energy is dissipated in stages rather than overwhelming a single device.

How often should an SPD be replaced?

SPDs are not permanent. They should be replaced:

When the status indicator turns red (often after multiple surges).

Or approximately every 3–5 years, as MOV components degrade over time.

Can AC and DC surge protectors be used interchangeably?

No, they cannot.

AC and DC systems have different voltage behaviors, interruption methods, and polarity. You must choose a dedicated AC or DC SPD. Incorrect usage can lead to ineffective protection or even equipment failure.

Does an SPD require grounding?

Yes, grounding is mandatory.

The SPD must be properly grounded to safely divert surge current to earth. Poor or missing grounding can render the device ineffective and may lead to discharge failure or electrical fires.

Conclusion

Surge protectors aren't just another component — they're a frontline defense for your power system. Knowing how to identify a high-quality SPD will save you from breakdowns, system failures, and safety risks.

At YRO, we offer a wide selection of AC and DC surge suppressors tailored for solar systems, control cabinets, industrial panels, and EV infrastructure. With in-house R&D and more than a decade of production experience, we provide both standard models and OEM solutions to help your electrical systems stay protected — always.

Need a reliable lightning arrester for your next project? Contact YRO today for OEM/ODM inquiries or bulk pricing.