Question { Infotech, 59362 }

how does electrical train works and what type of motors are
used to drive the train?
which level of supply voltage is used?

Answer

Electric train runs by using either DC Series Motor or 3-
phase Induction motor
the train receives 25kv voltage, transformer in it steps
down the voltage to 600v ac and then converted to dc for dc
series motor and 750v ac for induction motors.

Question { Core Solutions, 13020 }

generally on the roadside v hav 11kv line which is being
step down to 440v line to line....so any1 can tell me which
type of transformer they r using whether it is star to
delta,delta to star etc...???

Answer

The transformer is Delta - Star connected Transformer i.e.,
11kv is given to Delta connected side and 440v is given to
Star connected side of the transformer.
Delta side dont have neutral, while transmission neutral is
not needed.if neutral is used totally 4 wires have to be
used otherwise 3 wires are enough. 440v side we give to
homes, there a neutral is need so connected in star.
in Delta side line voltage = phase voltage. so 11kv voltage
is same.
homes need the voltage of 230v, in star the line voltage is
not equal to phase voltage. line voltage is 440v and phase
voltage is 230v.
so the transformer needed is Delta-Star