Heavy rain caused short circuit that led to fire at Newton MRT: SMRT VP Khoo Hean Siang

XIN MSN News, 14 Feb 2013
SMRT’s executive vice president of Trains, Khoo Hean Siang, said the incident could have been due to cable insulation issues.
He said: "Because of the heavy rain these few days, water could have seeped into the tunnel. ... It could be that the water seeped into the cable and caused this problem to occur. We are sending the cable to the lab to carry out a check (on) whether or not the insulation could have deteriorated."
Mr Khoo added that a similar incident occurred at Dhoby Ghaut MRT station in 2007. Full story

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SMRT Train's Executive Vice President: Heavy rain could be the cause to burnt cable at Newton MRT - Hardwarezone Forum