Why are switching power supplies prone to malfunctions? Be sure to pay attention to these details when choosing!

Some customer friends only focus on a few important parameters such as power, output voltage, efficiency, etc. and then hastily complete the selection when choosing a switching power supply. Finally, due to neglecting some small details, the power supply malfunctioned shortly after use.

For example, the factory building has an indoor environment that is not exposed to sunlight or rain, but is filled with metal dust; the application environment of beauty and teaching instruments is good, but there are strict requirements for noise; the equipment in the suburbs is powered from the power grid, and there is significant harmonic interference in the power grid. Faced with these special factors, choosing a conventional and universal switching power supply is very risky, and the failure rate of the power supply is thus increased.

Let's talk about the hidden dangers of these often overlooked details and how to avoid these "fatal risks" from the initial power selection.

1. Indoor Environment - Textile Machinery

The most headache inducing issue in the textile machinery industry is undoubtedly the issue of cotton wool. As shown in the figure below, cotton wool will inevitably drift towards every corner. The high-power power supply product comes with a fan, which makes it easier to suck the surrounding cotton wool into the fan and power supply, thereby causing malfunctions.

Pain point one: The malfunction includes the cotton wool jamming the fan, causing damage to the fan. The fan is damaged, and the power supply cannot dissipate heat which will cause the  power supply thermally damaged; This also includes the exposed metal pins of high-voltage devices (high-voltage capacitors, semiconductors). If sparks occur due to product abnormalities, there is a risk of igniting cotton wool and causing fire.

Solution: The LMF350-23BxxUH series adopts a fanless design, so there is no need to worry about fan damage that may cause equipment abnormalitie.The product adopts a glue filling process to seal the pins of high-voltage devices and avoid exposure.

Pain point 2: Textile equipment has a motor type load, which requires high-power startup at the moment of startup, and only requires small power to maintain operation after steady state. Many power supplies enter over power protection during the startup phase due to excessive output power, resulting in abnormal device startup and inability to function properly.

Solution: The LMF350-23BxxUH series has a "1.5 times transient overpower" performance to ensure normal equipment startup and meet motor applications.

2. Outdoor Environment - DC Pile

Charging stations are mostly installed outdoors, with large temperature differences throughout the year, and the outdoor environment is relatively humid and dusty.

Pain point 1: In outdoor environments, wind and rain can cause high humidity, which can easily damage the surface mount components on the PCB, leading to abnormal power supply and equipment malfunction.

Solution: The LMF200-23BxxUH product adopts a gluing process to encapsulate the PCB surface mount components, without fear of dust and moisture; Simultaneously improving the production process and enhancing corrosion resistance.

Pain point 2: In remote areas, highways, and other places, there are significant fluctuations in the power grid, especially at night, which can easily exceed the input voltage of conventional power sources (264Vac), leading to overvoltage damage to internal components; At the same time, outdoor lightning strikes are common, and lightning surges can easily damage the power supply, which requires the power supply to have high reliable EMS performance.

Solution: LMF200-23BxxUH product is a "305 full working condition" shell switch power supply, with an input voltage of up to 305Vac, fearless of power grid fluctuations; At the same time, EMS achieves level 4 protection, and the lightning surge protection performance reaches differential mode 2KV/common mode 4KV.

3. Switching power supply selection: pay attention to details and prescribe the right medicine for the situation

In different application environments, the operating conditions that equipment power supplies may face may vary greatly, and most of them are loss factors, such as power grid fluctuations, electromagnetic interference, metal dust, humidity, salt spray corrosive gases, temperature differences, and so on. The power supply is the core component of the equipment. Choosing the right power supply not only saves maintenance costs in the later stage, but also helps to enhance the competitiveness and brand power of the equipment. Choosing appropriate and reliable product designs for different application scenarios is the key.