i need 24v dc from 230v ac supply how we can getit ? what are the devices &its rating requied for that ? plzz i need answer urgently .thank u

3 Answers  

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What is difference between Over Current & Earth Fault protection?

0 Answers   ABC,

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Is necessary Protection CT, CLASS - 5P10 fitted at Incomer side of main Breaker ? Why ?

1 Answers  

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how it can be decided what will be the rating of CT and PT to be used in LT or HT cables?

3 Answers  

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hi pot test principal

1 Answers   NTPC,

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what are the energy savings methods that are existing in coal based power plant?

1 Answers  

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What is the In door to Out door Sub Station.

5 Answers   L&T,

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a 120 60 watt incandescent lamp has to be operated from 50 c/sec 1 phase ac supply. in order to do this a circuit element has to be connect in series with the lamp. which one of the following sries element is preferable.

1 Answers   SSC,

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When in a large power system if the demand of power is larger than the generated power the frequency of the power system drops.(assume the rated frequency is 50Hz and now it is 49Hz) So does this mean the demand is totally supplied with a lower value of generated power in a lower frequency?

1 Answers  

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what is meant by dedicated earthing?

1 Answers  

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can HT cable or HT bare conductor used for LT line? is yes what would be the current rating?

2 Answers   ACC, wbsedcl,

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We use ungrounded DC system (220V/110V) for control and protection system in substations etc. Suppose we have long 2 core DC cables running from our DCDB in control room to the load (length of around 2 to 3 km). Do we need to protect these long DC cables from earth leakages or not? If yes how?

5 Answers   Siemens,

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