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IS it important to make a stability test for Sepam before the commissioning protection functions such as 64REF?

Generally, In Fact, we do not test the functionality of SEPAM (or other relays, generally talking) but by doing this test and by checking the wiring we guarantee that relay commissioning is done correctly as 64REF is stable. Furthermore, if the fault is simulated on “out zone” area to be sure that wiring is done correctly and relay won’t trip in out zone area as shown in the schematic below.

As you see a fault is shown in “out zone” area and by related CT connection the both current calculated inside relay from I1,I2 and I3 ∑3I , an Io measured in Io or I’o have same direction, so according to 64REF formula the current seen by 64REF would be zero. If the CT connection is done wrongly then 64REF will trip for out zone and not in zone faults. 
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