When selecting a LED dimming power supply, in addition to considering conventional parameters such as the dimming method (such as DALI-2, Triac, 0-10V, DMX512, etc.), power range, output voltage, and output current, it is also crucial to pay attention to performance parameters often overlooked: THD, EMI, and surge protection. These parameters are closely related to the safety, stability, and lifespan of the lighting system and the lamps.

What is THD？

THD (Total Harmonic Distortion) is an important index to measure the proportion of harmonic components in the output current or voltage of a dimming power supply. Simply put, it reflects the degree of "interference" of a dimming power supply to the power grid. The higher the THD value, the greater the interference of the dimming power supply to the power grid and the more significant the impact.

Effects of High THD

Increase the power grid loss and affect the power quality

Harmonics will increase the burden of power supply system, resulting in an increase in reactive power and a decrease in grid efficiency.

Interfere with the normal operation of precision equipment

Especially in hospitals, laboratories and other scenarios, harmonic interference can affect the accuracy of precision instruments.

Resulting in reduced efficiency of the lighting system

The "cumulative effect" of a large number of harmonic currents superposition will affect the operation efficiency and stability of the entire lighting system

Intelligent Power Supply with Low THD

The THD value of Suretron LED dimming power supply is better than the industry standard, usually less than 10%, which effectively guarantees the power quality and stability of the power grid system. It is especially suitable for use in intelligent building, industrial lighting, home lighting, hotel lighting, road lighting and other projects.

What is EMI?

EMI (Electromagnetic interference) is the phenomenon that electromagnetic energy generated by electronic equipment during operation interferes with other equipment. The high frequency switching action in LED dimming power supply is very easy to cause EMI problems.

Impact of EMI failure

Interfere with wireless communications

In places such as conference rooms, theaters and stations, electromagnetic interference can cause signal interruption

The dimming power supply itself is unstable

Strong EMI may feedback and interfere with the control circuit of the dimming power supply, causing the power supply to crash or flicker

Limit the market application of dimming power supply

It cannot be certified by country/region (EMC certification), and it cannot be legally sold or applied in some high-demand engineering projects

The advantages of Suretron LED dimming power supply in EMI

Suretron LED dimming power supply effectively suppresses EMI interference through strict EMC circuit layout and filtering scheme. At present, many products have passed EMC certification standards to ensure the reliable operation of lighting system.

What is a surge?

Surge refers to instantaneous high voltage impact, which is common in lightning strike, industrial equipment switching, large motor start-up and other scenarios. For outdoor, commercial, rail transit and other applications, surge protection capability is a key indicator that cannot be ignored.

Impact of weak surge protection

High surge protection capability

Suretron LED dimming power supply pays special attention to surge protection design, using common mode/differential mode protection circuit. Among them, Suretron constant current high-power series can easily deal with 6kV or even 10kV surge impact, which can protect the safety of power supply and lamps, especially suitable for outdoor lighting in high surge environment.

In addition to these electrical properties, what other factors will you pay special attention to in the actual selection process? Feel free to share your thoughts in the comments section, and we'll be discussing the most important issues in the next issue.