GE UR series Instruction Manual page 243

5 SETTINGS
Enchanced stability angle
Stability angle
Integrator
Trip request
Trip output
ARMED LED
Enchanced stability angle
Stability angle
Integrator
Trip request
Trip output
ARMED
• 87PC PICKUP DELAY: This setting specifies a pickup delay for the phase comparison element. This delays the start of
the coincidence detection by specified time. It does not affect start of the signal transmittal to the remote terminal.
• 87PC STOP TX: This setting selects a FlexLogic™ operand that is used to stop signal transmittal to the remote termi-
nal. This can be used in blocking schemes to accelerate tripping at the remote end and in tripping schemes to prevent
tripping at the remote end, if desirable.
• 87PC TX RESET DELAY: This setting specifies a time delay to prolong signal transmission to the remote end after
FDL drops off and is recommended for blocking schemes only. If mixed current is greater than 0.02 pu, then square
pulses will be transmitted. If mixed current is less than 0.02 pu, then continuous blocking signal will be transmitted for
blocking schemes.
• 87PC RESET DELAY: This setting is used to seal-in the output phase comparison element after operating by the time
defined by this setting. A value of 30 ms or higher is recommended. A value of 0 ms operates the element during inte-
grated coincidence only, meaning that the
• 87PC TRANS BLOCK PICKUP: This setting increases sensitivity during and after the clearing of an external fault and
prevents false tripping during transient current intervals. If a pickup delay is used, the this setting must be increased by
the time specified in the
87PC PICKUP DELAY
• 87PC TRANS BLOCK RESET: Resets transient blocking and allows tripping.
• 87PC CHNL LOSS TRIP WINDOW: This setting is applicable to the 2TL-UB-DPC-2FC scheme only. If a loss of carrier
is detected in the course of the fault, a trip is allowed for the time defined by this setting (default value is 0). The trip is
blocked after the expiration of this time window.
• 87PC HIGH-SPEED CONTACT 1 and 87PC HIGH-SPEED CONTACT 2: These settings allow decreasing of the trip-
ping time by up to ¼ of the power cycle by bypassing FlexLogic™ execution and sending trip command directly from
the 87PC function to the contact output. These setting are used for breaker 1 and 2 (if used) trip coil connections.
Phase comparison signals are important for the analysis of 87PC operation. As such, they are recorded in oscillography. A
list of the 87PC channels recorded in oscillography is shown below.
GE Multilin
Second coincidence timer
(a)
Second coincidence timer
(b)
Figure 5–45: ENHANCED TRIP SECURITY
output operand is set and reset on every cycle.
87PC OP
setting.
L60 Line Phase Comparison System
5.5 GROUPED ELEMENTS
Trip reset timer
Trip reset timer
831798A1.CDR
5
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