DC power supply test method
1. Output voltage adjustment
When manufacturing a switch power supply, * * testing steps are to adjust the output voltage to within the specified range. Only after completing this step can we ensure that the subsequent specifications can be met.
Usually, when adjusting the output voltage, the input AC voltage is set to the normal value (115Vac or 230Vac), and the output current is set to the normal value or full load current. Then, a digital voltmeter is used to measure the output voltage value of the power supply and adjust its potentiometer (VR) until the voltage reading is within the required range.
2. Power adjustment rate
The definition of power regulation rate is the ability of a power supply to provide a stable output voltage when the input voltage changes. To measure the power adjustment rate, the following equipment is required:
A. A power supply that can provide variable voltage capability, at least able to provide an input voltage range of * low to * high for the tested power supply.
B. A root mean square AC voltmeter is used to measure the input power supply voltage.
C. A precision DC voltmeter with an adjustment rate at least ten times higher than that of the tested object.
D. Variable load connected to the output terminal of the tested power supply.
The testing steps are as follows: After the tested power supply is thermally stabilized under normal input voltage and load conditions, measure and record its output voltage values at Min (low) Normal (normal) and Max (high) input voltages. The power regulation rate is usually measured as the percentage deviation of the power output voltage caused by changes in the input voltage under a normal nominal load.
3. Load adjustment rate
The definition of load adjustment rate is the ability of a power supply to provide stable output voltage when the output load current changes. The required equipment and connection method are similar to the adjustment rate of the measured power supply, but the difference is that a precise ammeter and an output series connection with the measured power supply are required.
The testing steps are as follows: After the tested power supply is thermally stabilized under normal input voltage and load conditions, measure the output voltage value under normal load, and then measure and record the output voltage values (Vmax and Vmin respectively) under low (Min) and high (Max) loads. The load adjustment rate is usually the percentage of power output voltage deviation caused by changes in load current under a normal fixed input voltage.
4. Comprehensive adjustment rate
The definition of comprehensive adjustment rate is the ability of a power supply to provide stable output voltage when the input voltage and output load current change. This is a comprehensive test of power regulation rate and load regulation rate, which can provide more accurate performance verification of the power supply under changing input voltage and load conditions.
