The fully charged voltage of a single lithium iron phosphate (LiFePO₄) cell is 3.65 V. Formula for calculating the number of strings: Number of strings = Full-charged battery pack voltage ÷ 3.65 V Example- 48 V battery pack: 48 ÷ 3.65 ≈ 13 strings (actual 13 × 3.65 = 47.45 V).- 60 V battery pack: 60 ÷ 3.65 ≈ 16 strings (actual 16 × 3.65 = 58.4 V). Remember: 18.25 V indicates a fully charged LiFePO₄ battery pack with 5 strings (3.65 V × 5)....

  The fully charged voltage of a single NCM/NCA cell is 4.20 V. Formula for calculating the number of strings: Number of strings = Full-charge voltage of battery pack ÷ 4.20 V Example- 48 V battery pack: 48 ÷ 4.20 ≈ 12 strings (actual 12 × 4.20 = 50.4 V).- 60 V battery pack: 60 ÷ 4.20 ≈ 14 strings (actual 14 × 4.20 = 58.8 V). Remember: 21.0 V indicates a fully charged 5-string NCM battery pack (4.20 V × 5)....

If a switching power supply is faulty, 90% of faults can be located by following the four steps of "Inspect - Test - Disconnect - Replace":   1. Inspect After powering off for 5 minutes, visually inspect the housing for bulging, burning, blown fuses, or capacitor leakage, taking photos for record.   2. Test Use a multimeter in the DC range to measure the main capacitor: 300 V ±10% at no load. Below 250 V indicates a defective rectifier bridge or filter. Measure the output: No load should be ±5% of the nominal value; short circuit should be 0 V, the fuse is intact, and the secondary rectifier is broken.   3. Disconnect Unplug the load and use a 30 W/12 V automotive light bulb as a dummy load: If the light bulb lights normally, the power supply is OK, and the problem lies with the load. If it does not light or flickers, proceed to the n...