Answer Posted / hitesh ambaliya
hopkinson's test is also known as regenerative test.There
are three methods of test of dc machine.1st is direct method
, 2nd is indirect and 3rd is regenerative .here in
hopkinson's test two identical machines are used. identical
means same ratings.one machine act as motor and second as
generator. both machines are mechanically coupled.now when
supply is given to the motor there is losses and output
given to the generator. so it produce power which is given
to the supply.so it is back to back test.so her less power
supply is required. approximately 3.7 v.the advantages of
this method is that less power is require. 2nd is this test
performs on full load test thus we can find temprture rise
on load.disadvantage of this test is that to get two
identical machines.
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