GE L90 Instruction Manual page 241

5 SETTINGS
• OPEN POLE VOLTAGE INPUT: This setting is used to Enable/Disable voltage input in making a logical decision. If line
VT (not bus VT) is available, voltage input can be set to "Enable".
• OPEN POLE VOLTAGE SOURCE: This setting is used to select the source for the voltage for the element.
φ
• OPEN POLE A(C) AUX CONTACT: These three settings used to select a FlexLogic™ operand reflecting the state of
phase A circuit breaker auxiliary contact 52b type (closed when main breaker contact is open) for single-pole tripping
applications. If 2 breakers per line are being employed, both breaker auxiliary contacts feeding into the AND gate (rep-
resenting auxiliary contacts connected in series) are to be assigned.
• OPEN POLE PICKUP DELAY: This setting is used to select the pickup delay of the element.
• OPEN POLE RESET DELAY: This setting is used to select the reset delay of the element. Depending on the particular
application and whether 1-pole or 3-pole tripping mode is used, this setting should be thoroughly considered. It should
comprise the reset time of the operating elements it used in conjunction with the breaker opening time and breaker
auxiliary contacts discrepancy with the main contacts.
SETTING
OPEN POLE
FUNCTION:
Disable=0
Enable=1
SETTING
OPEN POLE BLOCK:
Off=0
SETTING
OPEN POLE A
AUX CONTACT:
AND
Off=0
SETTING
OPEN POLE B
AUX CONTACT:
AND
Off=0
SETTING
OPEN POLE C
AUX CONTACT:
AND
Off=0
SETTING
OPEN POLE BROKEN
CONDUCTOR:
Enable=1
Disable=0
SETTING
SETTING
OPEN POLE
CURRENT PICKUP:
OPEN POLE
CURRENT SOURCE:
AND RUN
A A > SETTING
B B > SETTING
C C > SETTING
SETTING
OPEN POLE
VOLTAGE INPUT:
Enable=1
Disable=0
SETTING
OPEN POLE
VOLTAGE SOURCE:
RUN
WYE DELTA AND
VA < 75% Nominal
VAG or VAB
VBG or VBC VB < 75% Nominal
VCG or VCA
VC < 75% Nominal
GE Multilin
OR
AND
AND
AND
AND
Figure 5–92: OPEN POLE DETECTOR SCHEME LOGIC
L90 Line Differential Relay
5.5 GROUPED ELEMENTS
OR
OR
OR
OR
AND
AND
SETTING
OPEN POLE
PICKUP DELAY:
FLEXLOGIC OPERAND
OPEN POLE
RESET DELAY:
OPEN POLE OP
ANY PHASE
5
A OPEN POLE OP A
B OPEN POLE OP B
C OPEN POLE OP C
827047A6.CDR
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