GE b30, Instruction Manual, Page: 423 / 632

CHAPTER 5: SETTINGS GROUPED ELEMENTS
B30 BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 5-215
5
Main path sequence
Figure 5-109: Breaker failure main path sequence
The current supervision elements reset in less than 0.7 of a power cycle for any multiple of pickup current as shown in the
following figure.
Figure 5-110: Breaker failure overcurrent supervision reset time
Settings
BF1 MODE
— This setting is used to select the breaker failure operating mode: single or three pole.
BF1 USE AMP SUPV
— If set to "Yes," the element is initiated if current flowing through the breaker is above the supervision
pickup level.
BF1 USE SEAL-IN
— If set to "Yes," the element is sealed-in if current flowing through the breaker is above the supervision
pickup level.
BF1 3-POLE INITIATE
— This setting selects the FlexLogic operand that initiates three-pole tripping of the breaker.
BF1 RETRIP PICKUP DELAY
— This setting specifies a pickup delay for the re-trip command. Set this delay longer than the
possible spurious contact input activation duration due to transients or temporary DC grounds, taking into account the
contact input de-bounce time to avoid re-trip operation for such transients.
BF1 PH AMP SUPV PICKUP
— This setting is used to set the phase current initiation and seal-in supervision level. Generally this
setting detects the lowest expected fault current on the protected breaker. It can be set as low as necessary (lower than
breaker resistor current or lower than load current)—high-set and low-set current supervision guarantee correct operation.