Question { 3983 }

If my sfu is 64 Amp & its link is 32 Amp then at what
amp.my sfu will trip???

Answer

Your link is 32 Amps so if any more than that specified
32Amps current occurred means then the fuse link will trip
i.e. its blown out that fuse wire.

That 64Amps is mentioned the Switch Fuse Unit(SFU) withstand
capability.i.e. that SFU Unit can withstand upto 64Amps.

Question { 7815 }

why battery is connected in parallel ?

Answer

Battery connected in series:
If batteries are connected in series then the output
voltage is increased.

Battery connected in parallel:
If the batteries are connected in parallel than the
output current is increased

Note:
The batteries are connected in parallel or series it
only deponds upon needs of output increased current/
increased voltage.

Question { 7212 }

in three pin plug 6 Amp. 220v AC rating.
why earth pin diameter is higher than ohter two pin? what its
purpose ?

Answer

I think Mr.Kishore kumar said answer is correct.i.e. R=Pl/a
area of the conductor increases resistance
value dicreases .so high leakage current flows it thats why
the area of the earthing pin is big compare yhe phase and
neutral pins.

Question { CDS, 23108 }

Difference between MCC and PDB

Answer

MCC:
The MCC means Motor control center. in this MCC
connects the Motors.

PDB:
The PDB means Power distribution board. In this PDB
connects only the feeders(power supply feeders)... i.e the
distribution board means to distribute the powers only...

Question { 8962 }

What difference between MCB,MCCB,RCCB,ELCB please explain briefly with its rating.

Answer

MCB means Miniature Circuit Breaker -- it is used for upto
100Amps in the motor feeders.

MCCB menas Moulded case Circuit Breaker -- it is used for
25oAmps to 800Amps in the motor feeders.

ELCB means Earth Leakage Circuit Breaker -- it is used to
trip the Circuit breaker if any leakage fault occured means.

RCCB means Residual Current Circuit Breaker -- A residual
current device (RCD), or residual current
circuit breaker (RCCB), is an electrical wiring device that
disconnects a circuit whenever it detects that the electric
current is not balanced between the phase ("hot") conductor
and the neutral conductor. Such an imbalance is sometimes
caused by current leakage through the body of a person who
is grounded and accidentally touching the energized part of
the circuit.

Question { 4420 }

I need a 33/690V Dry type transformer.How to select IP
class for this transformer.This will be an outdoor
transformer located in a highly polluted environment.

Answer

you choose IP 65 protection with canopy for that dry type
transformer..

Question { 5486 }

what is the difference b/w neutral and ground?

Answer

Ground:
It doesnot give a zero reference point of the voltage
It doesnot maintain a voltage stability of the system
If any fault happens in the system means then the fault
current will passes to the ground terminal.

Neutral:
It gives a return path of current.
It maintains the voltage stability of the system.
It gives a zero reference point of the voltage.

NOTE:
In Practically the Neutral wire is connected to Earth
in the nearest substation.....

Question { 3848 }

Pls any send the cable selection chart.
at azeemk30@gmail.com

Answer

for which application you need cable selection chart???

Question { Siemens, 11672 }

what is the rating of power
generation in india?

Answer

415v, 6.6kv, 11kv, 20kv.......

Question { BARC, 87040 }

how to measure earth pit resistance

Answer

The earth pit resistance is measured by Megger meter. This
measurement will be done on every two months once in the site.

Question { 27540 }

How can decide the MVA rating of power transformer for
substation like 220/132, 132/66, 66/33kv etc or even higher
kv rating of substation????
Send me the strictly technical answer that shows your strong
technical aptitude.

Answer

The MVA rating is only based upon the generating MW capacity
of the plant.
For Example:
50MW is generated in the Powerplant.(i.e. Generator
capacity is:50MW,11kV,0.8P.F,3000RPM)
Now we like to connect this 50MW power to the E.B.grid
then we use one Step UP Transformer i.e. to step up the
voltage from 11kV to 220kV.
Now we can calculate the MVA rating of that step up
transformer as:
i) MVA = MW/costeta
MVA = 50/0.8 = 62.5MVA.

This is the answer.....

By,
Karthik(Engineer)

Question { 6898 }

can we use the step down transformer to step up transformer

Answer

ya,its possible.. for ex: using a 11kv/415volt step down
transformer, in this primary voltage is 11kV and the
secondary voltage is 415volt(step down transformer)... now
we giving the input voltage to the 415volt side of the
transformer now the primary voltage is 415volt and secondary
voltage is 11kV(step up transformer).....
The step up and step down transformer is deponds upon
the input voltage is feeding side of the transformer(Primary
or secondary side)

Question { Meinhardt, 3233 }

can we run all LT motors at 360 volts which are normally
rated 415+/-10% voltage rating

Answer

The above answer is correct. While we can run the motor
using the 360Volt then the motor will rotate only the lesser
amount of speed than the rated 3000/1500 rpm. and it cannot
give sufficient output...and also produces a heat in the
motor winding.......

Question { 5665 }

what is the use of 6.6kV/6.6kV Transformer???

Answer

Thanks for your answer...This type of transformer is only
for isolation purpose or any other purpose???

Question { 2462 }

After fault clearing in Tr line, whether the Metering core of
CT is comes to normal condition from saturation region & its
works as a normal condition?

Answer

yes,metering core C.T comes to normal position after fault
clearing in the Transmission line....