How to debug the DC stabilized power supply charger.
Debug steps
1. Visual inspection of the whole machine
After the circuit is installed, carefully check whether the components are wrongly installed or missing, check whether the solder joints have false welding, virtual welding, lap welding, continuous welding, etc., and check whether the polarity of the rectifier diode and electrolytic capacitor is reversed. , Whether the power cord is damaged, whether the lead connector is short-circuited, etc. If there is any problem, troubleshoot it in time. The resistance test can be carried out after checking it once and confirming that it is correct.
2. Measure static resistance
After the visual inspection is correct, perform power-on measurement of static parameters. Because the secondary load of the transformer should have a certain resistance value, and the DC resistance value is about 200Ω, use the resistance gear of the multimeter to detect the power plug. If the measured resistance value is lower than the secondary resistance value, the secondary load is short-circuited.
3. Check power supply safety
Check the key parts such as the secondary of the transformer and the output end of the rectifier, focusing on checking whether there is any obvious short circuit. If there is an obvious short circuit, it must be thoroughly checked and checked until the fault is eliminated. After checking, it can be powered on. After the power is turned on, you should concentrate, do not rush to measure the data and observe the results, and carefully feel whether there are abnormal phenomena such as smoke, ignition, odor, abnormal sound, abnormal heat, etc. If there is any abnormal situation, turn off the power immediately. Re-energize the test after the fault is eliminated, and beware of expanding the fault or even causing an accident. The normal situation should be that the power indicator light is on.
4. Measure the output voltage
Use a multimeter with a DC voltage of 10V to measure the DC voltage on the cross output plug (pay attention to the polarity of the red and black test leads of the multimeter), which should correspond to the indication of the toggle switch S1. Change the position of the toggle switch S1, and the output voltage should change accordingly (100% deviation from the nominal value of the panel is normal, and the value should be slightly higher than the rated voltage value when there is no load).
Toggle switch S2 to measure the output voltage polarity, which should be consistent with the panel position.
