How to limit current? 1. Operate in the case of power off , pull the small pull switch in the lower left corner to the left gear(current regulating). 2. Pull out the current regulating insert to the 2nd and 3rd ports of the wiring port, loosen the port screw with a screwdriver, and     tighten with a screwdriver (at this time, connect to the AC power), and then the voltage digital display shows 0.00V, and the     current shows the current current parameter. 3. Adjust the current knob(on the right side) , you can adjust the desired current limit parameter, and display the current parameter     synchronously with the digital display. 0-20A/0-15A/0-10A can be adjusted in the whole process. 4. Remove the adjustment current insert and plug it back into the original insert card holder. After removing the digital display, the     voltage is about 0.90V, and the current is 0.00A. 5. Pull the pull switch in the lower left corner to the right gear(open/use). 6. The power supply is in the parameter value of the desired current. Now you can adjust the voltage knob(the voltage digital display     shows the output voltage in real time), the current does not change. And the current reaches 95% of the current limiting parameter,     overload protection starts working. 7. The current digital display shows the current value of the device load at this time, and the load current is monitored in real time. And     not to swich the current knob because the limited current parameter will change when you witch the current knob. If there is no need for current limiting, use the general equipment, without the above operation, pull the pull switch in the lower left corner to the right "open (use)" gear, and turn the (current adjustment knob) clockwise to the top. The maximum current limit at this time is 20A/15A/10A, at this time the power supply parameter is the output 0-24V 20A/0-36V 15A/0-48V10A, which is equal to a 0-24V 20A /0-36V 15A/0-48V 10A switching power supply. 1. Switching power supply, convert AC 110V/220V to DC 0-12V(0-70A)/DC 0-24V(0-40A) / DC 0-36V(0-28A) / DC 0-48V(0-20A) 1000W. 2. Come with two knob switch: a 0-12/24/36/48V DC voltage fully adjustable switch, and a current fully adjustable switch, built in a multi-loop high precision and high-end potentiometer. 3. Dual high precision digital display the real-time output DC voltage and current. 4. Smart protections: support shortage protection, overload protection, overvoltage protection, surge protection, automatic recovery function. 5. Built-in intelligent temperature control cooling fan: it start working when the temperature is up to certain value, and stop working when no need cooling. 5. Dual input voltage, built-in 110V AC/220V AC toggle switch(on the back), the defualt voltage is 220V AC. 6. Wide input voltage range, widely used in kinds of DC equipments, DC motor stepless speed adjustment, battery charging, Industrial automation, LED light strip display, student experiment, communications, etc. Specification: Product: Switching Power Supply. Type: AC/DC power. Transistor Connection: Half bridge. PCB: FR-4 double sides double layers. Input: AC 220V±15%  6A  50HZ. AC 110V±15%  12A  60HZ. Output Voltage: DC 0-48V 0-20A (Max adjustable to 50V).