At present SR have highest number of WAP 4 in form of ED shed around 115 and RPM have 66 WAP 7 and also RPM and AJJ have much amount of Eloco. But the thing is these locos are being extensively used to haul trains within Kerala and Karnataka. Also Tamil Nadu and Kerala have more kms of electric lines than Karnataka and you should know that almost 7/10 of a train in SR use Eloco. But we still have some trains like 16332 using eloco upto Guntakal, Jayanti Janta using Eloco from CAPE to Guntakal. We have many trains within Kerala using using ED locos from Trivandrum,Ernakulam to Shoranur. 4 trains use ED,RPM locos upto Mangalore also. All the trains from Ernakulam,Coimbatore,TVC,Shoranur to Chennai,Delhi, Kolkata and Guwahati (till Rake reversal takes places)use SR loco.
ED,RPM,AJJ...
more... are busy extensively now if TSS completes at Tirur what will happen to Eloco,and if Erode-Karur-Trichy and Salem-Karur-Dindigul gets completed all trains except few will get eloco. Surely all the trains will get Eloco in the route Kurla cannot get Eloco till 2020-2021.
1.Dharmapuri line is Diesel line and work for electrification hasn't started
2.RVNL,when they will complete the work who knows.