i have 400/230v transformer and didnt done the neutral
eatrhing. i connected one lamp to one phase and neutral to
the earth. but the lamp is not glowing. again i connected
neutral to earth and repeated the same. then the lamp is
glowing. in the first condition i tested with a line tester
also, at that time the tesrer is glowing what is happening
i dont know can any one help me?

Answer Posted / amit khamesra

Very Simplr. As second point of trafo sec ( 230 V ) was not
grounded the current did not get the return path upto the
source. In second attempt. the second terminal being
earthed, the current got the return path thru earth.Hence
the lamp glow.

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