In daily use, due to the complex application environment and component damage, there may be no output after the ultra-low temperature start switching power supply is powered on, which will make the subsequent circuit unable to work normally. So, what are the common reasons for ultra-low temperature start switching power supply?
1. Lightning strike, surge or voltage spike at input
Check whether the fuse, rectifier bridge, plug-in resistor and other devices at the input front end of the product are damaged, and analyze the radio wave waveform through differential test. It is recommended to use in an environment that meets the EMS conditions in the technical manual. If it needs to be used in a worse environment, EMC filter and anti surge device shall be added at the front end of the product.
2. The input voltage exceeds the specification of the power supply product
Check whether the fuse, plug-in resistor, large capacitor and other devices at the input end of the product are in good condition, and test the input voltage waveform to judge. It is recommended to adjust the input voltage, use a power supply with appropriate voltage as the input, or replace it with a higher input power supply.
3. Foreign matters such as water drops or tin slag adhere to the product, resulting in internal short circuit.
Check whether the ambient humidity is within the specified range. Secondly, disassemble the product and check whether there are sundries on the surface of the patch and whether the bottom surface is clean. It is recommended to ensure that the test (use) environment is clean, the temperature and humidity are within the specification range, and the product is coated with three proofing paint when necessary.
4. The input line of ultra-low temperature startup switch power supply is disconnected or the port of the connecting line is in poor contact.
Troubleshooting: test whether the input voltage is normal from the input terminal at the bottom of the product. It is recommended to replace the intact connecting line, and the snap of the connecting line port should be clamped to avoid poor contact.
When everything is ready and officially started, no output or hiccups and jumps are found. It may be caused by external environmental interference or damage to external components, such as excessive output load or short circuit / capacitive load exceeding the specification value, resulting in instantaneous overcurrent during startup.
At this point, we recommend that the customer change the drive mode of the back-end load and do not use the direct drive of the power supply product.
Post time: Jun-13-2022