Large power system disturbances and their consequences, represent a challenging problem for the power industry and especially for the network system operators, the ones who are responsible for the network operation at large, its security and reliability. This fact has reinforced interest in the new generation of monitoring systems with the aim to gain if possible a precise and maximum knowledge about those disturbances and their impact. Most of these severe events with impact on the entire system typically occur in or near the transmission network and are therefore best monitored at transmission system level. This puts great demands on the equipments and in general restricts the use of the data since it becomes property of the transmission system operator. Synchronized Phasor Measurement System has emerged as a powerful tool to improve power systems performance and reliability and fault localization possibility. Typical example of fault event that occurred in the transmission system and which was well registered by Phasor Measurement Units (PMU) that are installed in the distribution system will be shown in this paper.