Answer Posted / prashant singh
the main factor to deside defferential relay is used in
transformer or motor or generator is-
1. the current ratio of primary & secondary winding.
2. the current ratio in motor o/p terminal and star
terminal of machine.
3. same as generator.
in normal machine like transformer we connect a ct
to the primary & secomdary winding. and after connecting ct
we take both side ct terminal and joint in differential
connection, in this connection the resultant current is
zero. if any foult is generate resultant is not zero. and
this is due to fault.
Is This Answer Correct ? | 1 Yes | 0 No |
Post New Answer View All Answers
what are the basic insulation levels & what its Unit
Application Comparison between 22KV (UE)and 33KV (E) system. Are we allowed to use 33KV (E) cable in lieu of 22KV (UE) cable. What are the technical disadvantages.
define as synchronous generator
What happens to a line-frequency of high-frequency transformer when it is first energized/ re-energize?
Can you tell me more about pu systems (per unit systems )calculation in large power systems? how to get the base for voltage and power in generator, transformator and transmission lines?
What is the mechanism of WTI
How seriving & testing of the HT & LT breakers are done. What are the standard Ir values on which we can come to know the test is passed or failed?
What is the maximum operating temperature for a thermoplastic insulated cable?
What is the loss of transformer of 220kv/11kv, 63/80 MVA and 18.05% impedance
Two bulbs of 100w and 40w respectively connected in series across a 230v supply which bulb will glow bright and why?
what is load despatching
75 kw motor take 45 amp in no load delta in star 10 amp but in load it will take 160 amp but IR velue of winding above 500 at 1kw ph to earth and ph to ph. what problem it should be?
use of PIR in ehv breaker
11 kV line deraction check by an Engineer.
WHAT CAUSED THRESHOLD VOLTAGE TO EXIST?