difference between directional and non directional over current relay
difference between directional and non directional over current relay
(OP)
hi
I am a new engineer and want to know what is the precise difference between the AC directional over current relay (67) and ac non directional over current relay (51). In which case we have to use 67 and when to use 51. whether they can be used interchangebly or can not be used in that way. How does it affect in protection coordination.
regards
simatic
I am a new engineer and want to know what is the precise difference between the AC directional over current relay (67) and ac non directional over current relay (51). In which case we have to use 67 and when to use 51. whether they can be used interchangebly or can not be used in that way. How does it affect in protection coordination.
regards
simatic






RE: difference between directional and non directional over current relay
Please start from:
http
page 57.
Simple answer: directional is usually used in a closed ring connection, paralleling circuits and more and more.
Good Luck.
Slava
RE: difference between directional and non directional over current relay