Which of the following is an example of symmetrical fault?

The correct answer is option 1):(L - L - L)

Concept:

Symmetrical faults:

• The symmetrical fault is a fault where all phases are affected so that the system remains balanced
• A three-phase fault is a symmetrical fault As symmetrical faults result in balanced conditions,
• they may be analyzed using per-phase analysis
• L-L-L , L-L-L-G faults are symmetrical faults

Unsymmetrical Faults:

• Unsymmetrical faults are the faults that lead to unequal currents with unequal phase shifts in a three-phase system
• The unsymmetrical fault occurs in a system due to the presence of an open circuit or short circuit of transmission or distribution line
• It can occur either by natural disturbances or by manual errors
• The natural disturbances are heavy wind speed, ice loading on the lines, lightning strikes and other natural disasters.
• L-G, L-L, and L-L-G faults are asymmetrical faults.