Power supply is not a device to be operated by itself, so proper operation might not be secured due to wrong operation or matching to load. The below table shows symptoms which are often considered a power supply failure. Please check these points before returning it to the factory.
| Symptom | Cause | Check point |
|---|---|---|
| No output voltage | Wrong connection (especially input side) | Check the connection again. |
| Output voltage does not increase | Insufficient input current | Try with proper input power supply |
| Capacitance of input current is insufficient | ||
| Overcurrent condition | Check if voltage increase without load | |
| Output wire is broken | Check the conductivity | |
| Impedance of voltmeter to measure voltage monitor is not proper | Try with a voltmeter with over 10 MΩ impedance | |
| Voltage monitor is not correct | Impedance of voltmeter to measure voltage monitor is not proper | Try with a voltmeter with over 10 MΩ impedance |
| Current monitor is not correct There is offset |
Measure with ammeter | |
| Impedance of voltmeter to measure current monitor is not proper | ||
| Offset voltage is not cancelled | Cancel the offset referring to example of circuits in datasheet | |
| Make high frequency sound | Overcurrent condition | Check if there is still sound with rated load or without load |
| Ripple noise is larger than the datasheet specification | Noise is add on from outside | Try with input power supply with no noise |
| Shield the input wire | ||
| Earth at one point | ||
| Keep away from noise source |