ives ▁was ▁ 4 , 3 0 9 . ▁As ▁part ▁of ▁its ▁modern isation ▁plan , ▁Indian ▁Rail ways ▁imported ▁eigh teen ▁ 6 , 0 0 0 - hor se power ▁thy rist or ▁locomot ives ▁with ▁technology ▁transfer ; ▁they ▁are ▁now ▁produced ▁at ▁the ▁Ch itt aran jan ▁Lo comot ive ▁Works ▁( CL W ). ▁Indian ▁Rail ways ▁have ▁developed ▁cho pper ▁technology ▁for ▁DC ▁electric ▁multiple ▁units ▁in ▁collaboration ▁with ▁the ▁B hab ha ▁At omic ▁Research ▁Centre ▁( B AR C ), ▁and ▁ 2 0 ▁motor ▁coach es ▁with ▁cho pper ▁technology ▁will ▁be ▁placed ▁in ▁service . ▁In ▁addition ▁to ▁being ▁less ▁maintenance - int ensive , ▁cho pper ▁technology ▁is ▁expected ▁to ▁have ▁an ▁energy ▁sav ings ▁of ▁ 3 0 ▁to ▁ 3 4 ▁percent ▁in ▁sub urban ▁service . ▁ ▁Equ ip ment ▁To ▁reduce ▁maintenance ▁costs ▁and ▁improve ▁the ▁reli ability ▁of ▁power - supp ly ▁systems , ▁CO RE ▁has ▁adopted ▁state - of - the - art ▁technology : ▁cast ▁res in ▁transform ers , ▁SF 6 ▁circuit ▁break ers ▁or ▁vac u um ▁switch ge ar , ▁long - c ree page ▁solid - core ▁ins ul ators ▁and ▁P TF E - neut ral ▁sections . ▁E ight - w he e led , ▁self - prop elled ▁O HE ▁ins pection ▁cars ▁have ▁been ▁introduced ▁to ▁improve ▁maintenance , ▁and ▁an ▁O HE ▁recording ▁car ▁has ▁been ▁requested ▁to ▁monitor ▁the ▁performance ▁of ▁overhead ▁equipment