GE M60 Instruction Manual page 347

CHAPTER 5: SETTINGS GROUPED ELEMENTS

— This setting selects the FlexLogic operand that represents the protected breaker normal-type auxiliary
BF1 BKR POS2 C
switch contact on pole C (52/a). This can be a multiplied contact. For single-pole operation, the scheme has the same
overall general concept 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 segregated on a per-pole basis. The overcurrent detectors have ganged settings. This setting is valid only
for single-pole breaker failure schemes.
Upon operation of the breaker failure element for a single pole trip command, a three-pole trip command needs to be
given via output operand .
BKR FAIL 1 TRIP OP
Figure 5-117: Single-pole breaker failure initiate logic
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M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL 5-219