Answer Posted / p. naik

MCB is acircuit-breaker which can provide protection only
in the cases of shor-circuit.They can only be operated
manually. MCCB's have provisions for both under/over
voltages, it has provisions for motr mechonism to be fitted
on it, which allows us to operate them electrically. MCCB's
have chnge over(NO & NC)contacts for both SD(faults) and SDE
(electrical faults) which can be utillised for providing
fault indication lamps. MCCB's have higher ratings than
MCB's. MCB's of diffrent types are B-curve(lighting
loads),C-curve(motors),D-curve(capacitive).Both operate in
almost a simillar manner having a fixed & moving contact,
but MCCB's been with more "ACCESSORIES".

iam preparing for rrb section engineer post in electrical branch.suggest the right textbook for my reference.fromwhere i will get the previous q.papers?

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Graphs of measuring power and speed on dc motor

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How can claculate to attain the desired PF in the line ( HOW Much KVAR is required ) Pls Give the formula? Equate Petrochemical 0 1 how to calculate sizing of NGTR (Transformer rating,Loading resistor value and Current rating of resistor) and what is the X/R ratio. Details : 11kV,Capacitance 1.73532 micro farads,40kA for 1sec. 0 1 What will happened. if we feed 3phase supplay to the stater with out insert the rotor. How much current will flow through the stater winnding? Equate Petrochemical 0 1 What is required of exietation to the alternater. 0 1 why star point of HT motor not earthed? Equate Petrochemical 0 1 Why we are getting low voltage in star connection? Equate Petrochemical 0 2 What's ND relay & it's functions? Equate Petrochemical 0 2 How instantanious short circuit current is calculated? its formula? Equate Petrochemical 0 2 What is servo Motor? What's the advantages of this motor over Induction motor? Equate Petrochemical 0 2 What is core CT & it's function? Equate Petrochemical 0 3 what is meant by star/delta voltages as 440/220 in a 3 phase induction motor, and why it should be connected on STAR IN 3 PHASE SUPPLY L & T 0 4 What is required of exietation to the alternater. KNB 1 23 what is the design voltage for 6.6KV 2000 KVAR HT capacitor? Consultancy 0 3 Pls explain about vfd control?Where it is used, Give some example? siemens 1 22 Please explain me abt PQ diagaram in the power sector. 0 9

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We are preparing another project which involves Waste heat recovery from a 1 MW GE Engine. The Engine in particular gives out flue gas at 487Deg C with a flow rate of 5650 kg/hour and this can be cooled to 180 Deg C. This gives a thermal output of ~ 594 KW that is available for input to VAM via heat exchanger / boiler. Additionally 581 KW will be available from engine jacket water (temperature profile 80/ 80 Deg C and a flow rate of 50m3/hr) Our estimation is that 300 TR of cooling is possible with a suitable VAM machine(s). Please advise what is the most suitable arrangement with maximum TR and min Capital expenditure. plz reply me as early as possible

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i have seen one 8.4 MW synchronous motor in a plant located in bellary it is fixed with brushless rotary rectifier ,anybody can explain its start up principle

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