Question { 5563 }

As we know,charged clouds(from which lightning stroke
initiates)may be charged with either +ve charge or -ve
charge.
Now say one cluster of cloude is fully charged with +ve
charge & another cluster is fully charged with -ve charge.
In the sky these two cluster of charged clouds have come in
such a distance that, if they come clouser by some few
yeards then the lightning discharge will take place between
these two cluster of clouds. Under such a situation an
Aircraft came inbetween. what happend??

Answer

The clouds are always negatively charged body and the earth
as the positively charge body. When rain comes the
rainfalls (distilledwater) serve as the electrolyte or the
medium in between of these two charged bodies. In this
case, considering the enormous wideness of the area of
earth covered by clouds, a dielectric phenomena happens and
the cuurent travels from clouds to earth. That is what we
see as lightning.

Regarding of the plane, it serves as an incident
interrupter between these two electrically charged bodies.
Is there any news or event that a plane passes thru clouds
hit by lightning? None.

Question { 15742 }

what is the function of RMU?

Answer

The use of RMU is to assure the alternative power supply in
case one of the feeder was lost. It is because in RMU
configuration there can be a choice of power supply either
from the counterclockwise or clockwise power supply with
respect to the load.

Question { 4357 }

WHAT IS DIFFERENCE BETWEEN POTENTIAL DIFFERENCE AND E.M.F?

Answer

Potential difference and emf are two different words but
same meaning. That is a vector caused the electrons to flow
or travel.

Question { ABB, 3943 }

what are the protections in 132 kv class electrical
systems.....? hw u define that in elctrical terms..?

.
.
.pls answr

Answer

in addition, differential relays for current and voltage
are necessities also to monitor considerable leakage of
current and difference in voltage (in case of two leg
switchgear for a make and break design) to a magnitude that
will activate tripping action or prevent closing of the bus
tie.

Question { L&T, 6331 }

why secondary of c.t. will kept open ?

Answer

The secondary of ct is never open. It is always in a closed
circuit as connected to another coil that produces magnetic
force to cause deflection (The more current passing thru
the primary is the more magnitude of force to cause
deflection to the needle) to the needle used in reading
amperes such as ammeter thus serving the purpose of ct, to
be able to measure current.