Basic Definition of Constant Voltage Mode and Constant Current Mode
The so-called constant voltage mode refers to the working mode in which the current value of the load changes within the rated range, while the output voltage of the DC power supply remains stable. That is, when the load changes and the output current changes, the output voltage remains at the set voltage value and remains unchanged.
The constant current mode refers to the working mode in which the resistance value of the DC load changes within the rated range, while the output current of the DC power supply remains stable. That is, when the resistance value of the load changes and the output voltage changes, the output current remains at the set current value and remains unchanged.
The working mode state of a DC power supply with a constant voltage/current mode should be determined based on the nature of the load. In general, when the load is loaded with rated voltage and the actual load current value is less than the set current value, the DC power supply operates in constant voltage mode; When the actual load current value is greater than the set current value, the DC power supply operates in constant current mode.
The states of constant voltage mode and constant current mode are complementary, that is, the DC power supply either operates in constant voltage mode or in constant current mode. Therefore, before operation, users should first set the required voltage or current value correctly based on the nature of the load and the resistance value of the load, and choose the usage mode that meets the load requirements.
Capacitive load application:
Because capacitive loads often cause an increase in output voltage, especially when the output voltage is adjusted from high to low, it can lead to a slow decrease in output voltage. Therefore, when in use, connecting a power resistor in parallel to the output terminal of the DC power supply and a diode in series between the output and the load can achieve better performance.
Inductive load application
When switching on or off the DC power supply or changing the output voltage, the inductive load will generate reverse induced electromotive force, which will affect the operation of the DC power supply and even cause damage to it. At this time, a diode is connected in series between the output end of the DC power supply and the load, and an RC absorption circuit consisting of a power resistor and a capacitor is connected in parallel at the load end, which can effectively protect the DC power supply.
