Metro services hit due to electrification problem

Delhi Metro services were disrupted today, the second time in five days, on Line 3 between Karol Bagh and R K Ashram Metro stations for over an hour due to over head electrification problems.
"The metro services were disrupted from 12:40 PM to 2:00 PM due to a problem in an insulator located on the over head electrification poles near R K Ashram Metro station," DMRC Corporate Communications Executive Director Anuj Dayal said.
It is the second time in five days since August 16 that an insulator has failed on Line 3.
"Prima facie it appears to be design defect in these insulators," Dayal said.

Thousands of commuters were left stranded on the station due to the unprecedented delay. Passengers travelling on the route are also frustrated about frequent recurrence of the snag.
To rectify the recurring problem, DMRC has decided to provide sealant at all existing insulators as a short term measure and plans to replace insulators as a permanent solution.

"There are about 2,776 insulators falling between R K Ashram and Dwarka Metro stations which are being attended to during the night hours after the closure of the train services," Dayal said.
However, DMRC will be able to replace only 25 insulators per night as the time available to work on such activities is about three to four hours, he said.

In urban Mass Rapid Metro operations, overhead electric supply poles are located at a distance of 40 meters with two insulators on each OHE mast.
Thus, the Metro electrical engineers will have to locate the faulty insulator after checking all insulators in that particular section.
The insulators used in Line 3 are made up of Ethyl Venyl Acetate, which was the prevalent technology when these insulators were installed. However, for the recent Metro corridors, insulators with silicon rubbers have been used, which is much advance over the earlier technology and the likelihood of such faults occurring on this type of insulators is less, Dayal said.