Question { 80919 }

what are the types of transformers

Answer

depending on application
1.Distribution
2.Power
3.Control
4.Auto
5.Isolation
6.Instrument potential
7.Instrument current
depending on construction
1.core type
2.shell type

Question { 8965 }

What about Reactive power.and role of that one?

Answer

hey guys i think reactive power is the power consumed by the
power system during starting . as no power s developed
during starting that s termed as useless power. but its not
reactive power plays a predominant role in power system

Question { TCS, 21338 }

AC current is flowing in a wire in your home how can you
measure it(name of the instrument)

Answer

tong tester and clamp on meter are the same . tong tester is
the technical name and clampon meter is the name used by
line mans

Question { Cummins, 18622 }

What is Automatic Voltage regulator(AVR)?

Answer

to understand the function of AVR first v have to understand
concept of reactive power....

all of u know reactive power..



a generator has active power and reactive power... infact
with out reactive power ther will be no generation..


reactive power is the one which is the power consumed for
the establishment of magnetic flux in the machine without
which no generation takes place....

coming to the AVR..
consider a generator supplying to the grid.. as the grid is
not purely resistive.. it generally is inductive since loads
connected to grid(consider industries)are inductive..
generator tries to draw reactive power from the grid for the
development of its magnetic flux...(under constant frequncy)




when frequncy changes ..it disturbs the magnetic flux ...so
the geneartor tries to draw more n more reactive power from
the grid.. if this happens .. rotor of the generator will
get heated due to this reactive power..


so here comes d AVR... avr produces the xtra amount of
voltage required for the machine to maintain its magnetic
fld so that (V/F) will be constant...


thats wat i feel.. inform if any corrections




when

Question { SysArc, 7500 }

What is the function of stater in tube light circuit?

Answer

Tube light requires two things to function . Very high starting voltage , and high voltage to continue the operation . The starter is a circuit which breaks at regular intervals . When you break a circuit and start again , high voltage spark takes place . This voltage is further amplified through the choke which is a transformer . Thus at the beginning the starter gives high voltage sparks . Due to this the current begins to flow through the tube and the tube begins to glow. Once the tube starts , the required voltage to sustain is quite low , which is provided by the choke .

If the starter is bad the tube does not start . If the choke is bad or if the gas is low , the tube does not sustain its light .