http://i92.photobucket.com/albums/l34/jaws677/ETAP_zpse29a761a.jpg
The
problem I have is that the TCC for Main Sub Incomer1 and Main Sub
Incomer2 (Two parallel breakers) are below the TCCs for FNC Feeder
Relay and Furnace Incomer Relay. With both Main Sub incomers closed
this should not be the case as they will share the current flowing to the
Furnace load. We need to coordinate the breaker with both Main Sub Incomers
closed.
For
now I have combined all parallel breakers as one so that I could get an idea of
the settings, but this is obviously not ideal.
I
was wonder if there is a better way to do this.
If
you look a the example in the Third Edition of the Protective Relay Application
Guide (PRAG), 1987 you will see that they combine that current for the two
parallel relays 1 and 2 on the TCC. (red line third from the right)
http://i92.photobucket.com/albums/l34/jaws677/PRAG1_zps17572d6d.jpg
http://i92.photobucket.com/albums/l34/jaws677/PRAG2_zpsc6c72de4.jpg
ETAP Parallel Feeding Breakers , TCCs and Coordination
