The Metro Rail Transit 3 (MRT-3) management on Thursday explained there's no ''negligence'' in the power supply glitch in one of its trains last September 6.

In a press briefing, MRT-3's chief Engineer Oscar Bongon said a short circuit caused the Overhead Catenary System (OCS) to be cut at the Guadalupe Station (going northbound).

"Based on joint investigation of DOTr ( Department of Transportation) MRT-3 and our service provider Sumitomo, the root cause was initially from the train. There was a short circuit in the electrical box that induced high current," said Bongon.

"The train tracks have negative (energy) during the short circuit, while the electrical box was positive. The negative and positive had a connection which ignited fire in the electrical component of the train," he added.

MRT-3 Director for Operations Michael Capati said the damaged electrical box, placed under the train, fell to the tracks when a bolt which holds it melted. The high voltage generated by the short circuit then cut the Overhead Catenary System, he added.

No passenger was harmed but the smoke coming from one of the train cars caused some riders to panic.

The management said the train driver reported a failure even before arriving Guadalupe Station. The driver was then instructed to re-initialize and when no issue was detected, the train proceeded to operate until the small explosion happened.

Capati said there was no negligence within the management during the incident.

"We don't look at it as negligence because all our train undergoes a lot of checking. We don't release trains that doesn't pass by our thorough train preparation and preventive maintenance," he said.

Capati reiterated that Sumitomo was held responsible for the incident as the train's service provider. Still, he said the problem also stemmed from the poor condition of their trains and the tracks.

"They have a TOR (Terms of Reference), it's their responsibility if something ahppened to the train lines, if there is a failure, because the scope of work and maintenance is from the provider," he said.

He said the MRT-3 is set to undergo full rehabilitation next year.

"Part of the full rehabilitation program of Sumitomo is to replace all defective PCU (Protection and Control Unit)," he added. Cristina Eloisa Baclig/DMS