What to Consider When Selecting a Switching Power Supply
What should be noted when choosing a switch power supply?
In order to extend the lifespan of switch mode power supplies, it is recommended to choose models with an additional 30% output power rating. For example, if the system requires a 100W power supply, it is recommended to choose a power supply with an output power greater than 130W, and so on, which can effectively improve the lifespan of the power supply. In addition, it is necessary to consider the working environment temperature of the power supply and whether there are additional auxiliary heat dissipation devices. The rated output of the power supply will be reduced in high ambient temperatures. Select various functions according to the application requirements: protection functions: overvoltage protection (OVP), over temperature protection (OTP), overload protection (OLP), etc. Application functions: signal function (POWER GOOD, POWER FAIL), remote control function, telemetry function, parallel function, etc. Special functions: Power factor correction (PFC), uninterruptible power supply (UPS). Select the required safety regulations and electromagnetic compatibility (EMC) certifications.
May I ask if POWER can be used for 45~440Hz? If so, are there any other impacts?
Switching power supplies can generally be used within this frequency range. However, if the frequency of use is too low, it will cause a decrease in efficiency. For example, when the input voltage is 230VAC and the rated load is used, the efficiency is 84% when the frequency of the input AC power is 60Hz. However, if the frequency of the input AC power is reduced to 50Hz, the efficiency is 83.8%; When it is too high, it will cause the PF value of models with PFC function to decrease, and also increase the leakage current. For example, when the input AC frequency is 60Hz and the rated load is 230VAC, the power factor is 0.93 and the leakage current is 0.7mA; when the input AC frequency is 440Hz, the power factor decreases to 0.75 and the leakage current increases to 4.3mA.
