If a fan get trip and run in reverse direction due to system flow. Now in this condition during starting how can a VFD bring this negative speed to zero and later run in forward direction?

2 Answers   Aditya Birla, Siemens,

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if 11 lead acid batteries each 200 amph are connected in series so that combinly they can produce 110 volts dc. question is how much backup it can provide ? 2) how can we calculate that how much amprere and voltage is required to charge them . thanks in advance !

1 Answers  

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Why carbon brushes are used in motors?

6 Answers   BARC,

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Does VT metering core can be used for synchronizing.

1 Answers   Shrishti Power Technologies,

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What is the si unit

2 Answers  

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How do you calculate the actual power consumption of an inductive load appliance. Say, a deep freezer of 200watts

0 Answers  

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what is droop control?

0 Answers   BARC,

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what is the role of energy meter in distribution system ?

0 Answers  

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which calss ct's,pt', use protection,meatering and others

1 Answers  

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Why size of HT cable is less then LT cable inspite of the fact that voltage is higher in HT cable?

2 Answers   L&T,

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practicalLY what is impedence ...?

2 Answers  

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Why Stabilising Resistor used in REF circuit ?

0 Answers  

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