Traction Rolling Stock - Indian Railways Institute of Electrical ...

The voltmeter UA-1, UA-2 are fitted in the control desks and have double scale on which
the auxiliary voltage and the catenary voltage can be read.
5.4.4 Voltage stabilizer for headlight (RTPR)
The circuit is protected by fuse CCRTPR. This is meant for maintaining constant voltage
for the headlights of the locomotive to ensure that these provide a uniform level of illumination and
also to protect the lamps from fusing. It also feeds 24 V supply to the measuring instruments
through switch BL1LF and BL2LF. This is also provided with a 16 V tap for dimming the headlight.
5.4.5 Selsyn Transformer (TFS)
The transformer supplies 115 V AC supply to the system which transmit the position
of the tap changer GR to the control desk for indication after stepping down 230 V AC
supply.
5.4.6 Static Battery Charger CHBA
The static battery charger is fed from the supply of Arno converter. The unit comprises
of a stepdown transformer, magnetic amplifier and rectification unit. The charger is able to give an
output voltage of 110V DC and a load 20 Amps.
5.5 TRACTION CONTROL CIRCUIT
5.5.1 Compressed air for operation of pantographs and high voltage circuit breaker
When the pressure in the auxiliary air reservoir and in the compressed air lines to the
pantographs and the high voltage circuit breaker exceeds 5.5kg/cm² the pantographs may be
raised and the high voltage circuit breaker can be closed.
If the pressure lies below this value or drops while the pantographs are being raised it will
be necessary to start up the auxiliary compressor set. This is done by closing the switch ZCPA.
The pressure can be observed on the pressure gauge mounted above auxiliary
reservoir for pantograph in AC1 cubicle in Cab1
5.5.2 Operation of pantographs (Ref. fig. 5.5.2)
The pantographs are operated by the pantograph selector switch ZPT1 or ZPT2 in the
drivers desk. For this purpose the driver requires the operating key of the pantograph selector
switch.
The same operating key is required for unlocking the interlocking box BV and can be
removed from this box only when the key for the high voltage compartment doors have been
inserted and the roof earthing switch HOM has been opened or brought to normal working
position.
Further, the operating key of the pantograph selector switch can be removed or fitted
only in the zero position.
The pantograph selector switches have the following positions.
Position 0
– The two solenoid valves VEPT1 & VEPT2 are switched off the