Normal operation from the first train on the JR Yamanote Line

On the afternoon of the 20th, the Yamanote Line was expected to operate at a reduced frequency of about 10% due to electrical system trouble at a substation of JR East, but the restoration work has been completed and the line has been operating as usual since the first train.

On the afternoon of the 20th, six lines in the Tokyo metropolitan area, including the Yamanote and Saikyo lines, were suspended for up to 4 hours and 20 minutes due to electrical system trouble at a JR East substation in Shibuya, Tokyo.

Due to this problem, JR East initially expected to reduce the number of trains on the Yamanote Line by about 10% from the first train, but the restoration work has been completed and trains are running as usual from the first train.

On the other hand, according to JR East, damage was found in the cables outside the substation, and they are continuing to investigate the cause in detail.

Source: https://www3.nhk.or.jp/news/html/20210621/k10013095191000.html