GE UR Series Instruction Manual page 191

5 SETTINGS
BF1 PH AMP HISET PICKUP:
This setting is used to set the phase current output supervision level. Generally this setting should detect the lowest
expected fault current on the protected breaker, before a breaker opening resistor is inserted.
BF1 N AMP HISET PICKUP (valid only for 3-pole breaker failure schemes):
This setting sets the neutral current output supervision level. Generally this setting should detect the lowest expected fault
current on the protected breaker, before a breaker opening resistor is inserted. Neutral current supervision is used only in
the three pole scheme to provide increased sensitivity.
BF1 PH AMP LOSET PICKUP:
This setting sets the phase current output supervision level. Generally this setting should detect the lowest expected fault
current on the protected breaker, after a breaker opening resistor is inserted (approximately 90% of the resistor current).
BF1 N AMP LOSET PICKUP (valid only for 3-pole breaker failure schemes):
This setting sets the neutral current output supervision level. Generally this setting should detect the lowest expected fault
current on the protected breaker, after a breaker opening resistor is inserted (approximately 90% of the resistor current).
BF1 LOSET TIME DELAY:
This setting is used to set the pickup delay for current detection after opening resistor insertion.
BF1 TRIP DROPOUT DELAY:
This setting is used to set the period of time for which the trip output is sealed-in. This timer must be coordinated with the
automatic reclosing scheme of the failed breaker, to which the breaker failure element sends a cancel reclosure signal.
Reclosure of a remote breaker can also be prevented by holding a Transfer Trip signal on longer than the "reclaim" time.
BF1 PH A INITIATE / BF1 PH B INITIATE / BF 1 PH C INITIATE: (only valid for 1-pole breaker failure schemes)
These settings select the FlexLogic™ operand to initiate phase A, B, or C single-pole tripping of the breaker and the phase
A, B, or C portion of the scheme, accordingly.
φ
BF1 BKR POS1 B / BF1 BKR POS 1
These settings select the FlexLogic™ operand to represents the protected breaker early-type auxiliary switch contact on
poles B or C, accordingly. This contact is normally a non-multiplied Form-A contact. The contact may even be adjusted to
have the shortest possible operating time.
φ
BF1 BKR POS2 B (valid only for 1-pole breaker failure schemes):
Selects the FlexLogic™ operand that represents the protected breaker normal-type auxiliary switch contact on pole B (52/
a). This may be a multiplied contact.
φ
BF1 BKR POS2 C (valid only for 1-pole breaker failure schemes):
This setting selects the FlexLogic™ operand that represents the protected breaker normal-type auxiliary switch contact on
pole C (52/a). This may be a multiplied contact. For single-pole operation, the scheme has the same overall general con-
cept except that it provides re-tripping of each single pole of the protected breaker. The approach shown in the following
single pole tripping diagram uses the initiating information to determine which pole is supposed to trip. The logic is segre-
gated on a per-pole basis. The overcurrent detectors have ganged settings.
Upon operation of the breaker failure element for a single pole trip command, a 3-pole trip command should be given via
output operand "BF1 TRIP OP".
GE Power Management
φ
C (valid only for 1-pole breaker failure schemes):
L90 Line Differential Relay
5.5 GROUPED ELEMENTS
5-107
5