1. Leakage: After the seal of the electrolytic capacitor is damaged, the electrolyte leaks out,
   causing corrosion of surrounding components or short circuits.
2. Appearance deformation and expansion: If the shell of an non-polarized Bipolar Aluminum Electrolytic Capacitors deforms,
   expands, or bulges, it is usually due to internal gas production (such as electrolytic decomposition) causing the shell to deform,
   and in extreme cases, it may burst.   
3. Abnormal sound: If the non-polarized Bipolar Aluminum Electrolytic Capacitors emits abnormal "crackling", "
   popping" discharge sound or "buzzing" dull sound during operation, it indicates that there must be a fault inside the capacitor,
   and it should be stopped immediately for further inspection and treatment or replaced with a new one.
4. Switch tripping or fuse blowing: If the NP Aluminum Electrolytic Capacitors bank switch experiences an accident tripping or
   high-voltage drop and the fuse is blown, it should be shut down and the capacitor can only be put back into operation after
   confirming that there is no fault.

• Measure capacitance value: Use a multimeter or capacitance meter to measure the actual capacitance of the capacitor and compare it with the nominal value.
  If the difference is large (more than 20%), it may be damaged.
• Leakage test: Use an insulation resistance tester (megohmmeter) to measure the leakage resistance of the capacitor.
  If the leakage resistance value is significantly low, it indicates that the capacitor may have leakage problems.
• Short circuit and open circuit test: Use a multimeter to measure whether the capacitor is short circuited or open circuited.
  If it displays as short circuited (resistance close to 0 ohms) or open circuited (resistance infinite), the capacitor is damaged.
• Equivalent series resistance (ESR) test: Use an ESR tester to measure the equivalent series resistance of a capacitor.
  If the ESR value is high, it indicates that the internal losses of the NP Aluminum Electrolytic Capacitors have increased and may be damaged.

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