Kindly go through
bit.ly/dzpIcq
bit.ly/bntdpZ
REFUND DUE TO LATE RUNNING OF TRAINS :
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cancellation charge or clerkage shall be levied and full fare shall be refundable to all passengers holding Reserved, RAC, and Waitlisted tickets, if the journey is not undertaken due to late running of the train by more than 3 hours of the scheduled departure of the train from the journey commencing station provided that the ticket is surrendered upto the maximum time limits prescribed in clause (c) of sub-rule (1) of rule 6 .Which is given below:
Full refund will be permitted even after the departure of train in the event of train running more than 3 hours late and that the time limits will be up to 3 hours if the distance of the ticket is up to 200Kms., up to 6 hours if the distance of the ticket is 201-500 Kms. and up to 12 hours after the departure of the train if the distance of the ticket is more than 500 Kms.

Your mind is not really here Mr Basu, but in catching your bus to Ooty, that too, thanks to me :) LOL..
The rules you quote are for originating trains ! The question is whether the person who is arriving at NDLS late by another train, and misses a train leaving later than his train's arrival what would be the refund !
@Kerala Express Traveller: There is NO concept of pairing or connecting train in your case. If Kerala Express is likely to reach NDLS late, and you miss the DDN Shatabdi, you...
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must file a TDR online if it is an e-ticket. If it is i-ticket, you can file TDR, and obtain permissible refund from the counter at NDLS/NZM wherever you get down.
In case your Kerala Express is running inordinately late, say by 3 or or more hours, ask the Station Master to provide Train delayed Report, scan it, and file TDR online in case of etickets, and if it is i-ticket, obtain the same report, present it alongwith the DDN ticket, and hopefully you MAY get full refund.
Good wishes.