Planning of protection systems has been a significant task in order to achieve an efficient behavior of distribution systems. Feeders that offer high robustness and reliability are essential to ensure continuous energy delivering to all customer loads. Since distributed generation (DG) has increased its penetration in distribution systems, it has become necessary to place protective devices (such as reclosers) in order to allow DG islanded operation, which decreases the energy not supplied. This paper addresses efficient placement of normally closed reclosers (NCRs). A multi-objective optimization is defined to reduce SAIDI, SAIFI, and system costs. This approach yields optimal planning of NCRs by applying the non-dominated sorting differential evolution algorithm (NSDE). The NSDE is implemented in Matlab, while the power system is modeled in DigSILENT in order to employ a co-simulation environment. Simulations are developed on a real test feeder for two cases: i) without DG; and ii) with 6 MW penetration of distributed sources.