During voltage adjustment, it was found that the no-load voltage could not be increased.
Some operators prefer to turn the "current adjustment" potentiometer all the way to the left, resulting in the inability to adjust the power supply's unloaded voltage. This indicates a lack of substantial understanding of "current adjustment." Because even when the power supply is unloaded, it consumes a tiny amount of current, and by turning the "current adjustment" to zero, not even a tiny current is released, of course, the unloaded voltage cannot be increased. Therefore, the "current adjustment" should generally not be turned to zero (rotating it to about a quarter turn to the right will prevent the above situation). General operation method: When using the power supply as a voltage regulator, turn the current adjustment knob fully counterclockwise and maintain it. Adjust the voltage adjustment knob to control the output DC voltage value. When using the power supply as a current source, turn the voltage adjustment knob fully counterclockwise and maintain it. Adjust the current adjustment knob to control the output DC current value. Aviation Power Supply
Output with voltage but no current, or with current but no voltage
In either scenario, the power supply operates normally. Operators should check if their load is properly connected, if there are any short circuits or open circuits in the load, and whether the load meets the specifications, among other factors. In extreme cases, if the power supply outputs voltage (constant voltage state) and the load line is broken, the natural output current will be zero. Similarly, if the power supply outputs current (constant current state) and the load is short-circuited, the natural output voltage will be zero. 400Hz Variable Frequency Power Supply
The power supply provides both voltage and current outputs, but when trying to adjust the voltage, it can't be increased anymore, or when trying to increase the current output, it can't be boosted further.
This is due to the operator's lack of clarity regarding the "constant voltage" and "constant current" concepts. If the "constant voltage" light is on, it indicates that the power supply is operating in constant voltage mode (where voltage takes the lead). At this point, the output current size is determined by the load, not by the operator's adjustment—meaning the current is in a passive role. If you turn the "current adjustment" knob clockwise at this time, the current will not increase. However, if you turn the "voltage adjustment" knob clockwise, the output voltage will rise, and the output current will also increase accordingly—voltage is the main factor, while current is secondary.
Likewise, if the "constant current" light is on, it indicates that the power supply is operating in constant current mode. At this point, the output voltage is not adjusted in but determined by the load. Only by adjusting the "current adjustment" knob will the output current change, and the output voltage will also vary accordingly. Here, the current is primary, and the voltage is secondary. In summary, it's essential to understand the primary and secondary relationships. When the power supply is in "constant current" mode, adjust the current; when it's in "constant voltage" mode, adjust the voltage to change the voltage and current on the load. 400HZ power supply
