9424200996 79-7
BE1-11m Troubleshooting
Why don't the targets or trip LED work properly?
If a protective element is tripping at the desired level, but the targets aren't behaving as expected, use
BESTCOMSPlus to verify that the targets are enabled for the protective function. Refer to the Fault
Reporting chapter for detailed information about targets.
Trip LED behavior depends on the pickup and trip expression of the protective function. When the
functions pickup expression is true and the trip expression is false, the Trip LED flashes. In other words, a
flashing LED means that a protection element is in a picked up state and is timing toward a trip. When
both the pickup and trip expression is true, the Trip LED lights steadily. The Trip LED also lights steadily
when neither expression is true but latched targets exist. When resetting a target, the Trip LED will not
turn off if the fault is still present. The truth table of Table 79-1 serves as an aid to interpreting Trip LED
indications.
Table 79-1. Trip LED Truth Table
Why are voltage dependent elements (51/27, 27, 59, 32, 55) not operating as expected
when testing by secondary injections?
The BE1-11m has the ability to distinguish a loss of fuse from a loss of voltage. Check the sequence of
events for a Fuse Loss alarm. If a Fuse Loss alarm is active, voltage dependent elements will not
operate. Refer to the Fuse Loss (60FL) chapter for information on applying voltage and current so the
BE1-11m does not detect a fuse loss. Fuse Loss protection can also be disabled for the protection
element being tested.
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