Answer Posted / tareq harb

voltage regulator main purpose is to keep system output
voltage constant as much as possible under the load
changes. through controlling excitation current that is
injected to field coils.

what's prime importance of protection in electrical system.if protection system don't work properly what can happen in electrical system?

1904

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Sir,In our company there are 3 caterpillar make(capacity:(1) 3.3KV,2.5MW(2)3.3KV,2.5MW & (3)3.3KV,1.9MW) & 1 deutz make (capacity:11KV,3.8MW)gas engines utilised,all are running in paralell. There are three transformer utilised,(1) 6.25MVA,3.3KV/22KV,Impedence voltage:6.7% used for two generator,both are 2.5MW(2)5.5MVA,3.3KV/22KV,Impedence voltage:7.2% used for one generator of 2.5MW & (3) 5.5MVA,11KV/22KV,Impedence voltage:7.8% used for one generator of 2.5MW.all generator breakers capacity of 1250Amps. Sir,I want the details of fault level calculation of generator,transformer individually & for whole system. If you require any information from me.feel free for contact me sir.pl.send the answer of my question as the earliest as possible.

2120

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why is a power transformer used only occasionally?it is used to step up at generating stations?and that needs to be done all day long !!!!!!!

1865

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Showing results for capital, machinery, stock,wages, carriage in words, salaries, factory rent, repairs, fuel and power, buildings, debtors, sales, purchases, creditors, return outwords, return inwords, drawings, discount allowed, discount receivable, office expenses, bills payable, bills receivable, cash in hand, cash at bank, office rent comes under debit or credit

1515

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What is the Surge for 1.1 Phase Induction Motor(For Eg.1Hp) 2.3 Phase Induction Motor(For Eg.1Hp) 3.AirConditioner(For Eg 1Ton) 4.Refrigerator(For Eg 180Ltr or 160kW) 5.Induction Cooker 4. Ceiling Fan

2046

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In cable sizing calculation (determining the max route length of cable) why we choose the shortest length between cable length of full load current Iflc & starting current Istart?

3310

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what is the purpose of silicon dropper used in battery charger?

7443

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What is a commutator?

1040

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what is difference between speed mode and torque mode in motor?? explain in simple words please.

1588

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please send previous exams question papers

1816

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What should be the percentage increase in length of the dead end clamp for bus bar conductor (Hawthorn) after hydraulic pressing and what should be the applied pressure?

1928

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Explain about how is it working Earth fault'relay and wahts the resistance value of earth bed

1523

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1. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.

2020

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please explain to me how to calculate current,voltage,resistance with formula??

1429

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HOW WORK HEAT PLATE EXCHANGER

1975

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