why the CT ratio secondary is always divided by 5 for eg(
75/5,80/5,50/5)

Answer Posted / iamdon

CT is used mainly for Instrumentation(Measurement and
protection system) purposes thats why it is also termed as
instrument transformer.The measuring and protecting devices
are not rated to sustain high currents.What a CT does is,
it lowers the current in secondary side so that measurement
as well protection can be done at a reduced level of
current.

The digit in CT ratio of secondary side is IS standard for
rated secondary current so that uniformity among manufactures
be established.
The various values of secondary currents are
1)in the range of 0-5 amp e.g, 1A,5A
2)in the order of mA(particularly 40mA)in case of digital
devices for measurements and protection.


Perhaps Shayam had ingnored this fact.It cann't be any
number.

Author:arbelectbit@yahoo.com

Is This Answer Correct ?    15 Yes 2 No



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