Chennai train services to southern districts were disrupted for nearly three hours on Friday evening after smoke was detected in a signalling panel room at Karunguzhi station near Chengalpet, leaving several thousand passengers stranded and delaying trains by up to four hours.
The disruption affected the rail section between Chengalpattu and Madurantakam after railway staff noticed smoke in the panel room following a downpour. Officials switched off the electronic equipment and trains were operated manually through the affected section while the problem was assessed.
At least six southbound express, Chennai-bound and suburban services were affected, according to the report. Nine trains originating from Egmore and travelling towards southern destinations, including the Tiruchendur, Kollam, Kanyakumari, Pearl City, Pothigai, Nellai and Pandian expresses, ran between two and four hours late.
The affected section is part of a busy route linking Chennai with several southern districts. The delays stranded passengers at stations and disrupted journeys during the evening period, when long-distance and suburban services operate alongside other rail traffic.
Railway officials said switching off the electronic equipment helped prevent further damage. Manual operations allowed trains to pass through the affected section during the disruption, although services continued to face delays while inspections were carried out.
Signalling systems regulate the movement of trains and are a core safety component of railway operations. The incident also drew attention to the vulnerability of signalling equipment during the monsoon, when heavy rain and water exposure can affect railway electrical and control infrastructure. Former Divisional Railway Users’ Consultative Committee member R Mathiazhagan called for preventive inspections of signalling panels across Southern Railway’s jurisdiction.
“It is very important that Southern Railway checks the condition of signalling panels across its jurisdiction. Regular maintenance is essential, especially during the monsoon, as signalling systems play a crucial role in allowing trains to move safely. If the issue had worsened, it could have led to a tragedy,” Mathiazhagan said.
The signal system resumed after inspections by about 9 pm, following which services gradually returned to normal. A railway official said inspection teams would be formed and further action would be taken to determine what caused the signal panel failure.
