Question { 9411 }

How do you protect your appliances from harm in case of
neutral failure in a three phase power supply set up.

Answer

Whenever neutral fails in three phase system, the connected
loads will get connected between phases owing to floating
neutral.Hence depending on load resistance across these
phases, the voltage keeps varying between 230V to 400V.A
suitable servo stabilizer with wide input voltage range with
high & low cutoff may help in protecting the equipments.

Question { 4701 }

Does human body can effect the electric shock when stand on
Insulated material?

Answer

When you isolate yourself from the ground by standing on an
insulator and touch a live wire, depending on the
resistivity of the inulator, a small current may flow
through your body to the ground and if it is negligible, you
may not feel anything. but if you wet your body and carryout
the the same experiment, then you may be at risk of a shock
as yor body resistance would have come down drastically.All
said and done, the resistivity of the material chosen as
inulator is very important.

Question { 5474 }

how many winding in the single phase transformer?

Answer

Single phase transformer can have more than one winding in
both primary and secondary.These are known as tappings that
are used for selecting different voltages.