Answer / nagarajan

Ring main units not only used for High voltage,for LV
distribution purpose also it is being used.during the
operating of RMU back feedings possibilities are ther so we
must ensure after the isolation because two individual
power sources are connected to the RMU. So first isolate
both the source and make earth main circuit.Discharge if it
is high voltage side.Put lock out and tags caution lables
on the both the sources.

Answer / prabhu gnanasekaran

RMU Stands for RING MAIN UNIT.
iF IT IS Power motor control center there will be 2 i/c
with a tie switch whereas if one fails the bus - coupler
gets closed then the routine loads are supplied this
arrangement is provided inorder to avoid the interruption
in power cut.
RMU also falls on the same concept but there will be 2 or
more incoming cable from different sub station but of same
voltage levels.
RMU comes into picture for uninterpted power supply for
industrial sectors also for other sectors.
RMU IS a big topic on protection and other basic things
which cannot be concluded in this.
it is crisp information that all

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