WHY IS RESTRICTED EARTH FUALT PROTECTION NEEDED?? WHY CANT
DEIFFERENTIAL PROTECTION SUFFICE???
Answer Posted / tomson philip
REF Protection- There may be number of feeders down-
stream on the T.F.So if an earth fault occurs in one
of such feeders, that fault should not disturb the
transformer.If the transformer is not protected with REF
what happens is, everytime there is a fault some where
on it's feeders,the T/F will trip and all feeders will
be affected. This will go on happening from feeder to
feeder and consumers get in to trouble unnecessarily. But
with REF ,the transformer will trip only when there is
earthfault within T/F itself, which very very seldom
only occurs.In other words T/F tripping restriced to fault
within cases only.But the case of out-going feeders is
not so safe as to avoid earth fault.They may be in
a jungle where tree branches can touch the conductor
and cause a tripping.So T/F with REF will not trip in
such situation and power interruption will be only in
the feeder affected.
Is This Answer Correct ? | 8 Yes | 8 No |
Post New Answer View All Answers
Is the installation of the filter cloths necessary before spreading the gravels at the transformer yards?
What is the approximate value of stacking factor?
what is ps impedance test
how invertor convert the dc into ac give brif detail
how to increase or decrease speed in DC shunt motor by DC convertor
how will we calculate the copper wire load..
WHAT IS THE DIFFERENE IN ACTION OF MCB,MCCB,RCCB
A 3 phase transformer's (Y-Y) Y and B phase is (Y and B connection not broken) broken from neutral and R and Nutral connection is ok, what will be the relay tripping and why
How select ELCB for 32amp. socket having quantity 12Nos. We have to do this wiring in PLANT. Please Also explain the incoming cable specification.
What is instrumental error?
how do i commission a distribution transformer knowing all its ratings and transformation ratios?d
what is differentila pilot supervision in the incomer control panel in the power station?
What do you mean by distribution transformers?
IN dc capacitive reactance is??
Instrument connected to a single phase supply