- Maintenance of Traction Power Supply installations
- Maintenance of Traction Overhead equipment
- Supervisory Remote Control System
- Construction activities pertaining to this section
- Monitoring of energy conservation in Electric Traction
- Monitoring of Railway Electrification Works
Progress of Electrification on South Central Railway
Electrification on SCR started with the electrification of Vijayawada - Gudur section in 1980. By the end of July 2016, a total of 2,479 Route kms and 6,140 Track kms have been electrified, spreading over five divisions Secunderabad, Hyderabad, Vijayawada, Guntur and Guntakal of SCR. Out of the total 5,746 (BG) Route kilometers of track on SCR, 2,479 Route kilometres i.e., 43% of the total track have been electrified .
- Vijayawada - Gudur
- Vijayawada - Guntur - Nallapadu
- Vijayawada - Kazipet - Ballarshah
- Visakhapatnam - Vijayawada
- Gudur - Renigunta – Tirupati – Pakala – Katpadi
- Renigunta – Kadapa - Guntakal
- Kazipet - Secunderabad - Hyderabad – Sanathnagar – Tandur - Wadi
- Guntur - Tenali
- Samalkot - Kakinada
- Motumarri – Jaggayapeta - Mellacheruvu
- Dornakal - Karepalli - Singareni collieries – Bhadrachalam - Manuguru
- Manikgarh – Gadchandur
- Sanathnagar - Lingampalli Under Multi Modal Transport
- Secunderabad - Falaknuma System of twin cities
Electrification under progress:
- Guntakal – Wadi
- Nallapadu – Guntakal
- MMTS Phase – II
- Mellacheruvu – Jhanpad
- Vijayawada – Machilipatnam, Gudivada-Bhimavaram & Narsapur –Nidadavolu
- Guntakal –Bellary
- Guntur-Tenali (Doubling)
Total Route Km.
Total Track Km.
System of working of Electric Traction :
The Electric supply from the State Grid is availed at 220/132 KV, 2 Phase and is stepped down to 25 KV, Single Phase at the Traction sub-stations. This 25 KV single phase supply is fed to the over head conductor system consisting of a grooved contact wire suspended from catenary wire by flexible droppers. There is a continuous sliding contact between the pantograph pan of the locomotive and the bottom of the contact wire. The pantograph of the locomotive when raised applies a pressure of 7.0 Kg/Cm² against the contact wire which ensures the continuous and smooth collection of current from the Over Head Conductor to the locomotive. The 25 KV supply is further stepped down and rectified and fed to the Traction Motors. The return current flows through the loco wheels to the Rails and form the Rails to the earthed terminal of the traction transformer thus completing the single phase electric circuit. As the rails are earthed, it is ensured that the potential of the return current, is not increased above the earth potential. This ensures that there is no electric hazard to the public coming in contact with electrified tracks. The speed variation of the locomotive is achieved by varying the input voltage to the traction motors.
- In the newly electrified sections, 21.6/30.24 MVA Power Transformers have been provided at Traction Sub-stations (TSS). The capacity of these transformers can be increased from 21.6 MVA to 30.24 MVA by switching on forced air circulation fans.
- The switch gear at the TSSs is of state-of-art SF-6/ vaccum type. These switch gears require less maintenance as compared to oil switch gears, which were in use so far.
- Provision of improved version of distance protection relays at TSSs to avoid spurious circuit breaker trippings and consequent interruptions to OHE power supply.
- Provision of insulated copper cadmium catenary wire under Foot Over Bridges/ Road Over Bridges to avoid power supply interruptions to OHE on account of bird/ monkey menace.
- Provision of PTFE type short neutral sections in OHE to avoid stalling of Goods trains in gradient section.
- The manually operated isolators at major yards have been motorized to facilitate quick isolation of faulty section of OHE and to reduce the detention to trains to main lines during breakdowns/ unusual occurrences.
- Contactless Remote Sensing Device is used for identifying hot spots pertaining to connectors of the OHE jumpers, Busbars etc., of the TSSs/ Switching stations and to plan attention prior to failure.
- Provision of long creepage Insulators for the OHE situated in polluted zone to avoid flash over and consequent failure of insulators.
- Provision of Hybrid Insulators where OHE is prone for stone pelting activity by miscreants/cow-boys.
- Provision of High speed Auto reclosures to all feeder circuit breakers to minimize power supply interruption to OHE.
- Provision of Numerical relays in place of electromagnetic type relays.
Special Features of SCADA:
- PC based computer remote control system with the following special features have been installed at Secunderabad, Hyderabad, Vijayawada and Guntakal.
- All operations of Circuit Breakers, Interruptors etc., situated in the Sub-stations and Switching Stations over the length of Railway line can be remotely operated from the Divisional Control Office by simple commands through key board/mouse
- The status of different equipment and values of voltages and currents are continuously monitored and displayed on the video monitors attached to the operator workstations.
- Automatic fault isolation is done by SCADA system in case of faults on OHE
- All the operations of the TPC and events are automatically logged in the system
- All the traction masts and structures are earthed properly so as to negate any possibility of electric shock due to any leakage of power. Sufficient clearances are maintained with earthed structures. A working clearance of two meters is maintained from the live OHE.
Some of the Safety Tips to be followed by "PUBLIC"to Safely travel in Electrified section are here under:
- Do not carry vertically long poles/ any other articles in the vicinity of overhead live conductors.
- Do not touch/ walk on Rails.
- Do not travel on roof of coaches and wagons, as overhead live conductors are fatal.
- Tress-passing in electrified station yards is strictly prohibited for your own safety.
- Do not project any metallic parts from Foot over bridge / Road over bridge towards live wires and conductors.
- Do not pour water from Road over bridges/ Foot over bridges on the overhead wires and conductors.
- Do not lean out from compartment while train is in motion.
- Do not travel on top of Road vehicles passing through Level Crossing Gates.
- Do not try to pass through Level Crossing Gates with consignments higher than the height gauge level.
- Do not forget that Overhead Traction wires are always live and dangerous.