Abstract – This paper proposes the design of an algorithm to
detect fault in underground cable for blocking auto-reclosing in
distribution feeder of Metropolitan Electricity Authority (MEA).
The algorithm consists of two major steps. First, overcurrent
detection algorithm is applied to compare fault current with
current setting. Next process, the impedance detection is used to
identify the fault location base on comparing between the
measuring and the setting of impedance value. Finally, these
results (current & impedance) are used to make a decision of
auto-recloser blocking. This paper also shows the results from
software simulation and hardware simulation.