Table of Contents
Advertisement
2 CALCULATION OF SETTINGS
1202: NUMRCVR - Select Number Of Receivers
Set NUMRCVR equal to the number of receivers to be used with the selected scheme.
1203: TRIPMODE - Select 1-Phase / 3-Phase Trip Mode (Single Phase Tripping model only)
Any one of the following modes of tripping can be selected:
1.
3POLE -with this selection, three-pole tripping will be initiated for all faults regardless of the fault type
2.
1POLE -with this selection, single-pole tripping will be initiated for single line to ground faults and three-pole tripping
will be initiated for all multi-phase faults
3.
1POLEZ2 - with this selection, tripping will be the same as with the 1POLE setting with the additional feature that sin-
gle-pole tripping will also be initiated for Zone 2 time delayed single-line-to-ground faults
1204: CARRSTART - Function to Start Carrier in BLOCKING Scheme
This setting determines the function that will be used to start carrier (in addition to the phase and ground distance blocking
functions) when a BLOCKING scheme is selected. Any one of the following can be selected:
1.
DIR - with this selection, carrier will be started by the operation of the NB and IPB functions.
2.
IPB - with this selection carrier will be started by the operation of the IPB function.
3.
FD - with this selection will be started by the operation of the fault detector (FD) function.
1205: WKINFTRIP - Select Weak Infeed Tripping in HYBRID Scheme
This setting determines if the Weak Infeed Trip logic will be used when a HYBRID scheme is selected. One of the following
can be selected:
1.
YES - with this selection, the Weak Infeed Tripping logic is enabled.
2.
NO - with this selection, the Weak Infeed Tripping logic is disabled, but the Channel Repeat (Echo) logic remains in
service.
A Voltage Fault Detector (VFD) is used with the Current Fault Detector (FD) in the Hybrid scheme. The weak sides produce
little or no fault current at the weak terminal and the current values may not be sufficient to pick up the FD flag. In such
cases, the VFD is used to detect unbalance conditions or disturbances.
1301: TL1PICKUP - Trip Integrator
•
Step Distance Scheme: Timer TL1 is not used in a step distance scheme, therefore it is not necessary to make a set-
ting because any setting that is made will be ignored.
•
Blocking Scheme: Timer TL1 delays tripping at the local end until a blocking signal can be received from the remote
end of the line for an external fault beyond the remote terminal. The setting is determined by:
1.
The worst-case time coordination between the remote blocking functions and the local pilot tripping functions.
2.
The total remote-transmitter-keying to local-receiver-output time delay, which is equal to the back-to-back
channel time plus the channel propagation time.
Based on the above, use the following setting: TL1PICKUP = 3 + channel time + propagation time, where channel time
and propagation time are entered in milliseconds.
•
PUTT, POTT1, POTT2 and HYBRID Schemes: For these schemes, timer TL1 provides security against spurious
channel output during external faults within the reach of the overreaching trip functions. TL1PICKUP should be based
on the maximum output, if any, expected from the channel under these conditions.
•
Phase Identified Channel Schemes: For the HYBRIDP scheme, TL1PICKUP should be set to the larger of the fol-
lowing:
TL1PICKUP = 10 – channel time – propagation time, or TL1PICKUP = 3
GE Power Management
ALPS Advanced Line Protection System
2.3 PROTECTION SETTINGS
2.3.15 SCHMTIMERS
2-33
2
Advertisement
Table of Contents
