Answer / kuruvilla chacko

ohms law is applicable only to linear systems.a transformer
due to magnetic hysteresis and saturation is non linear and
doesnt follow the ohms law

what is the formula for efficiency of francis turbine and generator for hydropower? what is best way to select francis turbine and generator?

0 Answers   HAL,

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why the supply frequency in india is 50hz?

2 Answers  

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Can a transformer be used as voltage or current amplifier?

3 Answers   BPDB, REB, Riaz,

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what is AVR and tell principle and working?

10 Answers   ITC Infotech, MIOT Hospitals, YCC,

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At site, we have 30Kw motor (3 phase, 400V,50Hz) and FLC 54A as per the nameplate. At the time of starting it draws 840A instead of 390A (7.2%). As per the data sheet also its 390A starting current. it thru a dol starter from the MCC. can anyone tell what is the problem in the motor

5 Answers   ME,

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Draw SLD feeding from the SS up to distribution board of the load, calculate cable size, breaker sizes, and meter for the following case: Ground Floor: electric room, pump room, 5 shops, each is 15 KW First Floor: 5 shops, each is 15 KW Second Floor: showroom 30 KW Service Loads: water pump 3 KW (3ph) , fire pump 3 KW (3ph), and one DB service 12 KW (3ph).

0 Answers   FEWA, HMK,

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1)What will happen when 240 VDC supply is connected to 240VAC supply(DC supply +ve is connected to phase of AC supply & DC supply is to neutral of AC supply). 2)Also what will happen when 240 VDC supply is connected to 240 VAC supply in reverse polarity as of Sr. No 1.

2 Answers  

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In Aeroplane what circuitry or method use for earthing?

9 Answers   Bhel, EDA, Wind World,

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what is the multi strand cable size? 0.45mm is area of one strand & 370nos of strand.

1 Answers  

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before transformer oil dielectric strenght tests are taken the oil should be allowed to settle to remove option 1 air bubbles 2 gasses 3 contamination 4 water

0 Answers  

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Please send specifications for 1000KVA dry type transformer or where I can get the specifications?

2 Answers   PSU,

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What are the special cables required for explosion proof wiring?

2 Answers   IVRCL,

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