What causes a breaker to trip

A breaker (also known as a circuit breaker) trips when it detects an abnormal condition in the electrical circuit, such as:

  1. Overcurrent: When the current flowing through the circuit exceeds the rated capacity of the breaker or the wiring. This can be caused by:
    • A short circuit (a direct path between two conductors)
    • A ground fault (a path between a conductor and ground)
    • A fault in the load (e.g., a faulty appliance)
  2. Overvoltage: When the voltage in the circuit exceeds the rated voltage of the breaker or the wiring. This can be caused by:
    • A power surge or spike
    • A fault in the electrical distribution system
  3. Ground fault: When there is an unintended path between a conductor and ground, such as:
    • A faulty appliance or device
    • A damaged or worn-out wire
    • A lightning strike
  4. Arc fault: When there is an unintended electrical discharge between two conductors, such as:
    • A faulty appliance or device
    • A damaged or worn-out wire
    • A lightning strike
  5. Overheating: When the breaker or wiring is subjected to excessive heat, such as:
    • A faulty appliance or device
    • A wiring issue (e.g., loose connections)
    • A fire or other heat source
  6. Capacitive loading: When the circuit is subjected to a high amount of capacitive loading, such as:
    • A large number of fluorescent lights
    • A high-power motor
  7. Inrush current: When the circuit is subjected to a high inrush current, such as:
    • A motor starting up
    • A compressor or pump turning on
  8. Electromagnetic interference (EMI): When the circuit is subjected to electromagnetic interference from other devices or sources, such as:
    • Radio frequency interference (RFI)
    • Electromagnetic pulses (EMPs)

When a breaker trips, it opens the circuit to prevent further damage or electrical shock. It's an important safety feature that helps protect people and equipment from electrical hazards.