chetan joshi


{ City } nainital
< Country > india
* Profession * electrical engineer
User No # 27076
Total Questions Posted # 5
Total Answers Posted # 6

Total Answers Posted for My Questions # 38
Total Views for My Questions # 172519

Users Marked my Answers as Correct # 240
Users Marked my Answers as Wrong # 45
Questions / { chetan joshi }
Questions Answers Category Views Company eMail

Sir, plz tell me the relation b/w KW and frequency in Variable frequency Drive?

 2 Electrical Engineering 4113

sir, plz tell me how much kvar capacitor required for 1000 amp or 500 Kw load ? what is the formula ?

CSPL,

14 Electrical Engineering 32620

Sir, plz tell me how droop setting is done in parellel operation od DG set ? please give practical example ?

Honda,

Electrical Engineering 1657

what is the CT of protection and CT of metering ? what is class 5P10 & 5P20 and class PS ?

JEE Main, ONGC, VRA,

16 Electrical Engineering 125072

what is the working difference b/w softstarter and Variable frequency drive ?

Parle,

6 Electrical Engineering 9057



Answers / { chetan joshi }

Question { Electrical, 78366 }

What is the megger value for ht


Answer

the formula to calculate magger value is < KV + 1 , where
kv is the voltage , suppose for 415 v system its value is
0.415+1=<1.5 m ohm

Is This Answer Correct ?    81 Yes 18 No

Question { 29813 }

what are the difference between protection class CT and
Class PS CT


Answer

Protection class CT are 5 p10 and 5 p 20 and PS class ct
are used where neutral point is available such that star
conneccted secondary of Transformer and alternator ,it is
used for differential protection.

Is This Answer Correct ?    25 Yes 9 No


Question { Reliance, 53827 }

where to use CT and PT?


Answer

CT is used to measure a current, and PT is used to measure
voltage, CT can be used for metering and protection purpose
in substations while Pt is used to measure voltage.

Is This Answer Correct ?    116 Yes 12 No

Question { Suzlon, 5365 }

We wish to test 60 Hz systems from a 50 Hz supply. To
acheive frequency conversion, we use a VFD. The VFD powers
40 kVA transformer, which has motor and non-motor loads on
it. Will the transformer work?


Answer

since the transformer needs AC suppy , whether it is 50 hz,
or 60 hz. so it wll work.

Is This Answer Correct ?    9 Yes 3 No

Question { 7026 }

Simple calculation of improving power factor?


Answer

KVAR Required is

KVAR = P [tan (phi 1) - tan (phi 2) ]

where P = total KW
phi 1 = angle corresponds to power factor to be improved . ie cos ph 1 = 0.9

phi 2 = angle corresponds to power factor given . ie cos ph 2 = 0.7

Is This Answer Correct ?    6 Yes 1 No

Question { Bhel, 5330 }

Excat meaning of
burden in only one word?


Answer

burden is the total load connected across the secondary side of CT. Like 10 VA , 20Va etc

Is This Answer Correct ?    3 Yes 2 No