DC SPD Introduction

Time:2022-6-15 Category:Technical Knowledge


DC SPD (DC Surge Protect Device), also known as DC Surge Protector, is widely used in solar system. In this article, we will introduce what DC SPD is and USFULL DC SPD.

1. What is DC SPD?

Like its name, DC SPD is designed to protect against voltage surge in DC system, and it’s widely used in solar PV system.

Voltage surge in your solar system occurs pretty often. For example, voltage surge may happen in malfunctions of your solar power station.

And lightning strikes near your solar facilities will also induce voltage surges or spikes. Since solar systems are often exposed in large open spaces, typically in fields or on the rooftops of buildings, which increases the probability of getting voltage surges induced by lightning.

And the surges are very likely to shorten the service life or even damage your solar equipment if you don’t have a protection device.

That’s why we need DC SPD to protect your solar system against voltage surges, it will release the surge to the earth through ground wire and reduce the effect of surges.


USFULL DC SPD is made of top PC material, and its anti-flame character guarantee better protection for your solar system.

On the back of the DC SPD, there is a groove, which is used to install the DC SPD to standard 35mm din rail.

USFULL DC SPD’s Uc value ranges from 660V to 1500V, and the 1000V type is most commonly used. And the nominal discharge current ranges from 20kA to 40kA. And the protection level as Up is 3.8kV.

If you don’t know how to wire this, you can see this DC SPD connection diagram and finish wiring.

In the normal condition, indicate window stays green. After experience surges for many times, the indicate window will turn to red, and that means the core of the device needs to replaced

USFULL DC SPD strictly followed IEC international SPD standard and has CE certificates.

USFULL DC SPD is used in our USFULL PV combiner box as an important component of protection.

3. Summary

DC SPD is important for PV system for protecting against voltage surge. And choose USFULL DC SPD is choosing mindful surge protection pal.

Popular Products

  • USFULL DC Surge Protect Device

    • Rated output power:Kw
    • Voltage level:V
    • Rated input current:A
    • Rated output current:A
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