remote control equipment - Indian Railways Institute of Electrical ...

(d) High speed inter tripping relay. In the event of failure of traction sub-station, 25 KV
supply is extended from the adjacent sub-station by closing the bridging interruptor
at sectoining post Under such emergency feed conditons, wrong phase coupling
may be caused at the overlap oppostite the failed S. S. by the pantograph of the
locomotive, rasulting in the tripping of 25 KV CB at any one of two S/S through
wrong phase coupling relay (Mho). This may result in the formation of an arc at
the overlap due to which the OHE may be damaged. The damage due to arc can
be minimised by tripping the feeder circuit breaker at the other sub-station also.
This is achieved by an inter tripping arrangement through the remote control
equipment.
(e) Auto reclosing of feeder circuit breakers single shot auto-reclosing scheme for 25 KV
feeder circuit breakers at the traction sub-station has been adopted to facilitate
reclosing of the 25 KV feeder circuit breaker authomatically once after a preset
time delay after tripping of the circuit breaker on OHE fault. This feature will help
in quick restoration of traction power supply to OHE if the fault is of transient
nature. It will also help in checking the continuance of arc in the event of the
pantograph of a moving locomotive passing the overlap opposite the feeding post.
(f) Panto Flash Over protection relay : Panto Flash Over relay is provided for
protection of OHE from flash over at insulated over lap in front of Traction sub -
station, when pantograph passes from live OHE to dead OHE across the over lap.
This relay opens the closed feeder circuit breaker to prevent melting down of
OHE. Relay can be bypassed either locally or Remotely. One relay monitors one
Line.
Principle and Operation :
When ever one of section of insulating over-lap (IOL) is tripped on intermittent fault,
and electric train enters from live to dead section of the FP-IOL, there shall be a
heavy flash over, particularly when the Panto leaves the IOL which may damage the
Panto. The extent of damage is dependent upon the intensity of current drawn by
locomitive. to indentify such situtation and trip the feeder circuit breaker connected to
the live side of the overlap.
Refer Fig. PFRS the single line diagram of typical traction substration (TSS). One
side of the insulated overlap, A or B can become dead while other section is live
due to the tripping of respective feeder CB on fault or manual tripping. This
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