1)Why electric shock is feel ?? n in a Electric Train why
we didnt feel that ?
2)What is the reason for transformer Noise ??
3)What is relation b/w Transmission Lines & Communication
Lines ?
4)Which material is used for making Transformer oil & How u
measure its dielectric strength & Name the test ?
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Answer Posted / rajkumarsripelli
ya....this is rajkumarsripelli Testing engineer trasformer
division...
4ans: The dielectric strengh can be caluculated by oil
insulation breakdown test by using an equipment called as
oil insulation breakdown kit..in this kit will be having
two electrodes seperated by small distance in a small glass
tank.in that small tank we will be filling the oil to
test . by applying the required voltages like 10kv or
20kv ,30kv....(this voltages depends on tha transformer
ratings)between the electrodes we can see the results..
for example suppose we have oil of unknownbreak downvalue
(suppose 50KV)
. To test this oil we have to fill this oil into kit(tank)
and voltage will applied between the electrodes..from 0v to
60kv..so here the voltage will be increased slowly...if the
voltage reaches 49kv inside the tank we will not find any
flash over between the electrodes but when it reaches 50kv
the flash over will be taken between the two
electrodes...so by this test we can conform that given oil
is having breakdown value at 50kv...so this oil will be
used in transformers which are opearated with 33kv
voltages that means oil insulation breakdown value should
be double as compared to its normal operating volages...
thank u....
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