why Batteries & Battery chargers are used in substation? what is the different between UPS & battery charger?

4 Answers   DLF,

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STATE AND EXPLAIN SUPER POSITION THEOREM.

3 Answers   ABB,

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capacitor applied voltage is 1100VDC & capacitance value is 82uF how to calculate current of capacitor.

2 Answers  

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Define corner frequency?

0 Answers  

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Dear All, In a 400V power system, ratio of three current transformers installed incoming switchgear is 4000/1. Maximum three phases short circuit current of this system is 48kA. One CT is installed on neutral of upstream transformer (6/0.42kV, solidly earthed) for 51G protection. Would you please inform me about the correct CT ratio of this current transformer (on neutral)?? Thanks a million

2 Answers  

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what is the difference between relay and a contactor.

5 Answers   Siemens,

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What do you mean by linear and bilateral network?

20 Answers   Automation, Disa, EGCB, Infosys, OPTCL, TICT,

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when we have to use UPF wattmeter and LPF wattmeter? what is the difference between UPF and LPF wattmeter in terms of construction?

4 Answers  

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How we calculate the size of ht cable for any transformer

0 Answers   WalMart,

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advantages & Disadvantages of Solar power system?

2 Answers  

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what is divercity factor?

4 Answers   ABB,

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what is rating providing of contactor,relay,fuse unit for motor output power

2 Answers  

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