GE B90 - Bus Differential

CHAPTER 5: SETTINGS GROUPED ELEMENTS
B90 LOW IMPEDANCE BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 5-155
5
Each of the six setting group menus is identical. Setting group 1 (the default active group) is active automatically when no
other group is active.
If the device incorrectly switches to group 1 after power cycling, upgrade the firmware to version 7.31 or later to correct
this issue.
5.6.3 Bus differential
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  BUS DIFFERENTIAL  BUS ZONE 1(6) DIFFERENTIAL
Up to six zones of bus differential protection are provided, depending on the software options. The operation of these
elements is completely dependent on the dynamic bus replica, which must be defined first. Both restrained (biased) and
unrestrained (unbiased, instantaneous) bus differential protection functions are provided for each bus differential zone.
The biased bus differential function has a dual-slope operating characteristic (see figure below) operating in conjunction
with saturation detection and a directional comparison principle (see the logic diagram in this section).

 BREAKER FAILURE

See page 5-160

 VOLTAGE ELEMENTS

See page 5-168

 CURRENT ELEMENTS

See page 5-169

 END FAULT PROTECTION

See page 5-176
 BUS ZONE 1
 DIFFERENTIAL

BUS ZONE 1 DIF
FUNCTION: Disabled
Range: Disabled, Enabled

BUS ZONE 1 DIF
PICKUP: 0.100 pu
Range: 0.050 to 6.000 pu in steps of 0.001

BUS ZONE 1 DIF
LOW SLOPE: 25%
Range: 15 to 100% in steps of 1

BUS ZONE 1 DIF
LOW BPNT: 2.00 pu
Range: 1.00 to 30.00 pu in steps of 0.01

BUS ZONE 1 DIF
HIGH SLOPE: 60%
Range: 50 to 100% in steps of 1

BUS ZONE 1 DIF
HIGH BPNT: 8.00 pu
Range: 1.00 to 30.00 pu in steps of 0.01

BUS ZONE 1 DIF
HIGH SET: 15.00 pu
Range: 0.10 to 99.99 pu in steps of 0.01

BUS ZONE 1 DIF
SEAL-IN: 0.400 s
Range: 0.000 to 65.535 s in steps of 0.001

BUS ZONE 1 DIF SUPV:
On
Range: FlexLogic operand

BUS ZONE 1 DIF TRIP:
Off
Range: FlexLogic operand

BUS ZONE 1 DIF BLK:
Off
Range: FlexLogic operand

BUS ZONE 1 DIF
TARGET: Latched
Range: Self-reset, Latched, Disabled

BUS ZONE 1 DIF
EVENTS: Disabled
Range: Disabled, Enabled