Answer / george

oil emersed xformer- uses oil for cooling system

dry type xformer uses only his housing for cooling system.
we call it heat sink

Answer / raza

In Oil transformer, Mineral Oil is used for insulation and
cooling pupose but in dry type transformer, no any kind of
oil is used. In dry type transformer, other methods of
cooling are used i.e. air cold, water cold etc. and for
insulation purpose air, vaccume etc. are used.

In generation,transmission and distribution voltage frequency is either 50HZ or 60 HZ;why are only these frequencies?

2 Answers  

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What is the harm if we install primary side 11 KV VCB at a distance of one Km from the 11/3.3KV 12.5 MVA transformer through 11 KV cable.

4 Answers  

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what is the difference betwteen overcurrent and short circuit fault?

3 Answers  

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why is only master neutral contactor is made to switch in synchronization of dg sets

4 Answers   Honeywell,

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what is meant by impedance & transient protection?

0 Answers  

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i am using auto transformer for starting of induction motor to provide reduse voltages...but the principle of a tansformer according to definition"which transform energy to on circuit to another circuit with constant power and constant frequency". so if i am using reduse voltage then current obsely hige because power is same.but we use auto transfarmer for starting of induction motor to give low current.but here according to definition we are giving hige current.

0 Answers  

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Hi My Dear All Friends, There is one question it is widely used in Power Project's High Voltage Engineering. Question- What is the diffrence between Earth fault and Back up Earth Fault....???? . . . . . . Have A Good Day

1 Answers  

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what do you mean by every IC 74 first digit.why are you using this no.why not using another no.

0 Answers   Jaypee,

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which type of ICs can be used in resonant power converter?

1 Answers  

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Why the rating of dc machine is in HP??/ Do reply guys..Its very important......

4 Answers   Apollo,

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plz send me HPCL apptitude paper.. maulik_elect@yahoo.co.in

0 Answers   HPCL,

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a 3 phase slip ring induction motor is wound for 4 poles on stator and 6 poles on rotor; when 3 phase balanced voltage source at 50 hz is applied to motor it will run at a)1500rpm b)1000rpm c)750 rpm d)zero rpm

13 Answers   Essar, PSPCL, PSTCL,

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