Constantly changing dynamics of the power generation systems and increasing interest in power generation from distributed photovoltaic (DPV) systems is challenging for transmission and distribution systems, making things complicated for service providers. The lack of control and visibility over these DPVs from system operators causes problems in the power distribution system, especially during grid disturbances. The researcher's concern increased towards understanding the effects of grid disturbance on DPV inverters for a reliable network. Although technical standards provide guidance to DPV inverters for expected performance and behaviour, some guidelines are unclear under different grid disturbances. The behaviour of grid-connected inverters to voltage disturbances is critical for designing load composite models and tuning their parameters in planning power reserve requirements. The behaviour of single inverters is insufficient to understand the response of multiple inverters under such grid disturbances as distribution networks comprise several integrated DPV inverters. For this reason, the sensitivity analysis of 31 single-phase grid-connected DPV inverters was experimentally analyzed for fast voltage sag disturbance. DPV inverters behaviour is classified as i) ride-Through, ii) power curtailment, and iii) disconnection. The undesirable behaviour of DPV inverters threatens the stability of power systems with high DPV generation. The objective is to provide evidence to system operators for proper power scheduling and help in standard development.