manan gajjar


{ City } bhuj
< Country > india
* Profession *
User No # 107508
Total Questions Posted # 1
Total Answers Posted # 8

Total Answers Posted for My Questions # 0
Total Views for My Questions # 2213

Users Marked my Answers as Correct # 45
Users Marked my Answers as Wrong # 3
Questions / { manan gajjar }
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why Induction Generators are not "Black start" ? and apart from WTGs where this types of generator are generally used?

 Electrical Engineering 2213



Answers / { manan gajjar }

Question { 2621 }

what is the consuption rating of motor in one day


Answer

First calculate power consumption of motor.
P=√3*E*I*cosФ (assuming 3 phase motor)

now power consumption per day

P(kWh/day) = P(W) × t(h/day) / 1000(W/kW)

*conditions apply :D

Is This Answer Correct ?    0 Yes 0 No

Question { NPCIL, 8512 }

extremely urgent please, why a fuse is used before
voltmeter but not with a ammeter connected to a CT(current
transformer),thanks in anticipation.


Answer

Because during fault condition high transient voltage will occur thia voltage can damage voltmeter that is why we connect fuse across it, while in case of CT metering CT are made up of special core that can get saturated if voltage across its primary is beyond its limit, so no more current will flow during this condition, so there is no need to connect fuse with CT.

Is This Answer Correct ?    0 Yes 2 No


Question { NPCIL, 2971 }

why current transformer secondary is short circuited an what
will happen if connect very high resistance acrossthe
secondary side of current transformer?


Answer

In CT, high transient voltage will occur if secondary is not short circuited.
CT can withstand certain amount of burden not beyond that, if we connect more burden then CT's secondary can get damaged.

Is This Answer Correct ?    3 Yes 0 No

Question { 4560 }

Why we are using PLC instand of DCS in ESD System? can u
explain any one?


Answer

Because of the scan time.
the scan time of DCS is generally of 100ms to 1 sec. where scan time for PLC ia 10ms.

we want quick action in case of any emergency for that we are using PLC in ESD system.

Is This Answer Correct ?    2 Yes 1 No

Question { 8553 }

How to convert m3/hr in tonnes/hr


Answer

we calculate the flow generally in two types either by volume or by mass.

m3/hr unit is used for volumetric flow where tonnes/hr used for mass flow.

we can convert each other by this formula
Q(mass)= Q(volume) * Rho(density)

Is This Answer Correct ?    8 Yes 0 No

Question { Hi Spectra, 5506 }

What is the differences of Level swich( LS ) and Level Transmitter(LT)


Answer

Lavel switch is Digital input where it gives only two single either ON (1) or OFF (0).

where level transmitter gives analog output means value of the output will vary with respect to time.
generally its between 4 to 20mA.

Is This Answer Correct ?    12 Yes 0 No

Question { Edac, 3718 }

Why we are using thrust bearing at turbine side?


Answer

To withstand the axial load we are using thrust bearing in turbine.

Is This Answer Correct ?    3 Yes 0 No

Question { 4909 }

how to measure the output of RTD given the general formula of  rtd.  


Answer

RTD's output is resistance.
As we know RTD means resistance temperature detector, so we measure resistance across the terminal of RTD by multimeter.

Now assume measured resistance is "X" and RTD we are using is PT100 then,

T(temp)=(X-100)/(0.386)

*PT100 RTD shows 100 ohm at 0°c

Is This Answer Correct ?    17 Yes 0 No