Laboratory power supplies usually provide one control for the output voltage and one for the output current. While the output voltage can be easily observed and verified by the user, the current control is difficult to understand for many users, which is due to the function of the overcurrent limitation. First of all, it should be mentioned that you can force a voltage to a load and, for example, you can also supply a 12V device with only 9V, but you cannot force a load to take out a higher current than it needs. If, for example, the load connected to the laboratory power supply only uses “0. 5 A”, the current limit can also be set to “5 A” or “10 A”, the load will still only use “0. 5 A. ” Secondly, a load may require more power than the laboratory power supply supplies. Thus, a load that requires 15 A and connected to a 5 A laboratory power supply is always ensured that the laboratory power supply switches to the “CC” constant current mode, outputs its maximum current but causes the output voltage to collapse. The current control of the laboratory power supply acts only as an overcurrent limitation, which regulates the voltage when the current exceeds the maximum set value.