Schweitzer Engineering Laboratories SEL-351-5, Instruction Manual

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5.24
SEL-351-5, -6, -7 Relay Instruction Manual
Date Code 20070117
Trip and Target Logic
Directional Comparison Unblocking (DCUB) Logic
q From Figure 5.10 ; w Figure 5.1 .
Figure 5.11 Unblocking Block Logic Routing to Trip Logic
PTRX1, PTRX2—Permissive Trip Receive Outputs
In two-terminal line DCUB applications (setting ECOMM = DCUB1),
PTRX1 asserts for loss-of-channel or an actual received permissive trip.
In three-terminal line DCUB applications (setting ECOMM = DCUB2),
PTRX1 or PTRX2 assert for loss-of-channel or an actual received permissive
trip (for the respective Channel 1 or 2).
The PTRX1/PTRX2 Relay Word bits are then routed in various combinations
in
Figure 5.7 to control Relay Word bit PTRX, depending on enable setting
ECOMM = DCUB1 or DCUB2. Relay Word bit PTRX is the permissive trip
receive input into the trip logic in
Figure 5.1 .
Installation
Variations
Figure 5.13 shows output contacts
OUT105
and
OUT107
connected to separate
communication equipment, for the two remote terminals. Both output contacts
are programmed the same (OUT105 = KEY and OUT107 = KEY).
Depending on the installation, perhaps one output contact (e.g., OUT105 =
KEY) could be connected in parallel to both transmitter inputs (
TX
) on the
communication equipment in Figure 5.13 . Then output contact OUT107 can be
used for another function.
Figure 5.12 Connections to Communications Equipment for a Two-Terminal
Line DCUB Scheme (Setting ECOMM = DCUB1)
ECOMM = DCUB2
UBB1
ECOMM = DCUB1
to TRIP
Logic
w
UBB
UBB2
q
Relay
Word
Bit
Relay
Word
Bits
Setting
Setting
(—)
OUT105
OUT105 = KEY
TX
(+)
TRIP
(RX)
RX
TX
GUARD
(RX)
IN104
SEL-351
(Partial)
IN105
To / From
Remote
Terminal
PT1 = IN104
LOG1 = IN105