GE D60 Instruction Manual page 586

CONTROL ELEMENTS
The scheme generates output operands
signals to the remote end(s). Choices of communications channel include remote inputs/outputs and telecommunications
interfaces. When used with telecommunications facilities, assign the output operands to operate output contacts
connected to assert the individual bits at the interface.
To make the scheme a fully operational stand-alone feature, the scheme output operands must be configured to interface
with other relay functions, output contacts in particular. Typically, you program the output operands to initiate a trip,
breaker fail, and autoreclose, and drive a user-programmable LED as per user application. When used in conjunction with
the trip output element, the scheme is pre-configured to initiate trip, breaker fail, and single-pole autoreclose actions.
DUTT SCHEME BLOCK
from a pilot cut-out switch are typically used for this purpose.
DUTT SEAL-IN DELAY
time delay is applied to this operand for coping with noisy communication channels such as a power line carrier. The
is a minimum guaranteed duration of the
SEAL-IN DELAY
scheme, the trip operands
DUTT NO OF COMM BITS
bit available, the scheme sends the direct under-reaching transfer trip command on bit number 1
responds to the direct trip command received on bit number 1
identification provided by the Phase Selector to assert the output operands
through
DUTT RX1
signals for the scheme. Typically input contacts interfacing with a signaling system are used.
The DUTT scheme requires a secure and dependable signaling system. For this reason, a series/parallel combination of
receive signal "contacts" is often used. This is accomplished by using a multi-bit communications system to transmit
redundant copies of the
5
gate) or 2-out-of-3 voting logic) with FlexLogic. The
signals.
In single-bit applications,
applications,
DUTT RX1
signals from two or more remote terminals through OR gates in the FlexLogic, and configure the resulting signals as the
inputs
DUTT RX
5-372
(DUTT TX1
— This setting allows the user to assign any FlexLogic operand to block the scheme. Contact inputs
— The output FlexLogic operand
A, B, C, and
DUTT TRIP
— This setting specifies the number of bits available on the communications channel. With only one
— These settings allow the user to select the FlexLogic operands that represent the receive
DUTT RX4
signal (often via different paths) and building appropriate security logic (such as series (AND
TX
must be used. In two-bit applications,
DUTT RX1
, , , and
DUTT RX2 DUTT RX3
through TX4) that are used to transmit the direct under-reaching
DUTT
(DUTT OP) is produced according to the DUTT scheme logic. A seal-in
pulse. As this operand activates the Trip Table of the DUTT
DUTT OP
are sealed-in for the same period of time.
3P
(DUTT RX1 setting). The scheme uses only local fault type
DUTT TRIP
settings should be associated with the final (secure) TX
DUTT RX1(4)
DUTT RX1
must be used. In multi-terminal applications, connect the RX
DUTT RX4
D60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
(DUTT TX1 operand) and
A, B, C, and 3P.
and must be used. In four-bit
DUTT RX2
DUTT