how does relay works?

16 Answers  

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whay we transmit power in 3phase no in 4 or 2 or 5......etc?

4 Answers   CCCL,

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In a star-star connected h.t transformer why we use NGR on the secondary (l.t)side.

3 Answers   Star, TATA,

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my question is that....few days ago i had installed a three phase motor starter for an electric saw.the motor will run and make the hydraulic pressure which will be goes to pressure cylender by up and down lever.two number of limitswitches are also installed on cylinder for safety of motor.now when the arm of cylinder reaches to the upper or lower limit it will cut the motor's line.and motor will be stop.now wana know that what will i do that motor runs continue after the limitswitch cut it down but it shold not be made any pressure.pls answer me in brief.

3 Answers  

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if the stetor speed (N S) increase by 20% then the rotor speed will be increased by 20% is it true. ?

4 Answers  

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What is the difference between KW & KVA ?

9 Answers  

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UPS battery Back time = no.of Batteries * Ah of the Battery / output KVA * 130 ? what is the 130 means ? can any one help? because all are using this formula how its came 130?

2 Answers  

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Main CT ration is 400/5, meter CT ratio is open type: -/5A. What is the Multiplying factor of the meter, considering same PT ratio.

1 Answers  

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how to calculate transformer turn primary & secondary side 11kv to 420v

0 Answers  

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What is the differance between negative dc voltage and positive dc voltage because some circuit uses -24,-5,-12,- 15,volt dc supply

10 Answers   eLab, Hero Honda, NTPC, Suzlon, Teradyne,

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What is substation?

5 Answers   KSEB, Neolite,

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After synchronizing the running generator with grid, the avr getting tripped and the generator breaker also oettong tripped, before tripping the avr the pf meter of generator is showing leading pf please kindly give a suggestion to rectify this problem.

2 Answers   Thermax,

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