Answer / a.p.nanjappa

150kw , 440 is a large motr. the starting current of this
induction motor will be 5-8 times depend on drive ex-fan.
and coast for 6-8s to attain full speed.
so, the new contactor shall be good quality , with
overload,instantaneous with time delay shall be selected.
Reverse rotation protection, vibrations,
Unbalnced current protection optional.
LV power cable terminal box cable connection and support.

what is AVR and tell principle and working?

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How to check the specific gravity of the two 12 V batteries connected in series to a 24 V UPS and inverter ? will we have to disconnect all the connections and turn off the UPS and inverter or not ? will we have to check specific gravities in each cell of the two batteries ? what is the name of the instrument that is used to check the specific gravity and whats the procedure to check the specific gravity with it ? thanks

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1KVA transformer of different frequencies of 50hz,100hz,500hz&1000hz. which one of these transformer has big size? Give reason

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how to determine the cable size...pls explain me with the formula taking particular load....does the factors like impedance & short circuit rating influence the cable size, if so how....

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Why colled 440V to 3-phase supply.

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How can we calculate the efficiency of a Running (On-Load) Motor ? What parameters are required and what is the method ?

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Hello friends., my question is related to testing of current transformer... A Ct having knee point voltage of 750 volts., and I have two step up transformer's of rating 230 v to 440 volts., can I obtain the value of 750 volts by using the two transformer's.... If yes then how could I connect the transformer's to obtain knee point voltage?? thank you in advance

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what is KWH

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how is reactive power controlled on the transmission system

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why should a transformer be never connected to dc supply

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