This paper addresses the impact of the dynamic network reconfiguration (DNR) on the observability of harmonic voltages and currents in smart distribution systems. Optimal placement of power quality monitors (PQMs) is generally applied without taking into account the DNR. A test case is implemented and two indexes are proposed to assess the impact of the dynamic reconfiguration on the harmonic observability. The results show the need for new formulations for optimal placement of PQMs, where a configuration of the PQMs is selected while the impact of the DNR is as low as possible.