. ▁ ▁Sign alling ▁Sign alling ▁systems ▁are ▁also ▁being ▁upgrad ed , ▁with ▁the ▁sem aph ore ▁sign alling ▁system ▁being ▁replaced ▁by ▁a ▁col oured - light ▁sign alling ▁system . ▁Col our ▁light ▁signals ▁are ▁more ▁visible ▁to ▁train ▁drivers , ▁impro ving ▁safety ▁and ▁efficiency . ▁The ▁inter lock ing ▁system ▁is ▁being ▁changed ▁to ▁panel ▁or ▁relay ▁inter lock ing . ▁ ▁SC AD A ▁The ▁ 2 2 0 - 1 3 2 - 2 5 ▁k V ▁power - supp ly ▁network ▁for ▁elect r ification ▁extends ▁along ▁the ▁track ▁for ▁about ▁. ▁It ▁is ▁rem ot ely ▁controlled ▁from ▁the ▁division ▁control ▁centre ▁to ▁ensure ▁an ▁un inter rupted ▁power ▁supply ▁to ▁the ▁track ▁overhead ▁equipment . ▁In ▁elect r ification ▁projects , ▁a ▁micro processor - based ▁super vis ory ▁control ▁and ▁data ▁ac quisition ▁control ▁system ▁is ▁replacing ▁the ▁earlier ▁electro - me chan ical ▁St row ger ▁system ▁of ▁remote - control ▁equipment . ▁SC AD A ▁can ▁te lem eter ▁voltage , ▁current , ▁maximum ▁demand ▁and ▁power ▁factor ▁on ▁a ▁real - time ▁basis , ▁en abling ▁control ▁of ▁maximum ▁demand ▁and ▁elect rical ▁cost . ▁The ▁system ▁also ▁provides ▁automatic ▁troubles ho oting ▁and ▁isol ation ▁of ▁fault y ▁sections . ▁ ▁Tele communic ation ▁ ▁Opt ical ▁fib re ▁communic ations ▁Indian ▁Rail ways ▁have ▁implemented ▁communic ations ▁technology ▁using ▁optical ▁fib re ▁cable . ▁On ▁ 3 1 ▁March ▁ 2 0 1 2 , ▁ 4