GE UR Series L90, Инструкция по эксплуатации

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5-340 L90 Line Current Differential System GE Multilin
5.8 INPUTS/OUTPUTS 5 SETTINGS
5
VIRTUAL OUTPUT 1 ID:
"Trip"
VIRTUAL OUTPUT 1 EVENTS:
"Disabled"
5.8.5 REMOTE DEVICES
a) REMOTE INPUTS/OUTPUTS OVERVIEW
Remote inputs and outputs provide a means of exchanging digital state information between Ethernet-networked devices.
The IEC 61850 GSSE (Generic Substation State Event) and GOOSE (Generic Object Oriented Substation Event) stan-
dards are used.
The sharing of digital point state information between GSSE/GOOSE equipped relays is essentially an extension to Flex-
Logic, allowing distributed FlexLogic by making operands available to/from devices on a common communications net-
work. In addition to digital point states, GSSE/GOOSE messages identify the originator of the message and provide other
information required by the communication specification. All devices listen to network messages and capture data only from
messages that have originated in selected devices.
IEC 61850 GSSE messages are compatible with UCA GOOSE messages and contain a fixed set of digital points. IEC
61850 GOOSE messages can, in general, contain any configurable data items. When used by the remote input/output fea-
ture, IEC 61850 GOOSE messages contain the same data as GSSE messages.
Both GSSE and GOOSE messages are designed to be short, reliable, and high priority. GOOSE messages have additional
advantages over GSSE messages due to their support of VLAN (virtual LAN) and Ethernet priority tagging functionality.
The GSSE message structure contains space for 128 bit pairs representing digital point state information. The IEC 61850
specification provides 32 “DNA” bit pairs that represent the state of two pre-defined events and 30 user-defined events. All
remaining bit pairs are “UserSt” bit pairs, which are status bits representing user-definable events. The L90 implementation
provides 32 of the 96 available UserSt bit pairs.
The IEC 61850 specification includes features that are used to cope with the loss of communication between transmitting
and receiving devices. Each transmitting device will send a GSSE/GOOSE message upon a successful power-up, when
the state of any included point changes, or after a specified interval (the
default update time) if a change-of-state has not
occurred. The transmitting device also sends a ‘hold time’ which is set greater than four times the programmed default time
required by the receiving device.
Receiving devices are constantly monitoring the communications network for messages they require, as recognized by the
identification of the originating device carried in the message. Messages received from remote devices include the mes-
sage
time allowed to live . The receiving relay sets a timer assigned to the originating device to this time interval, and if it
has not received another message from this device at time-out, the remote device is declared to be non-communicating, so
it will use the programmed default state for all points from that specific remote device. If a message is received from a
remote device before the
time allowed to live expires, all points for that device are updated to the states contained in the
message and the hold timer is restarted. The status of a remote device, where “Offline” indicates non-communicating, can
be displayed.
The remote input/output facility provides for 32 remote inputs and 64 remote outputs.
The L90 provides an additional method of sharing digital point state information among different relays: direct messages.
Direct messages are only used between UR-series relays inter-connected via dedicated type 7X communications modules,
usually between substations. The digital state data conveyed by direct messages are direct inputs and direct outputs.
b) DIRECT MESSAGES
Direct messages are only used between UR-series relays containing the type 7X UR communications module. These mes-
sages are transmitted every one-half of the power frequency cycle (10 ms for 50 Hz and 8.33 ms for 60 Hz) This facility is
of particular value for pilot schemes and transfer tripping. Direct messaging is available on both single channel and dual
channel communications modules. The inputs and outputs on communications channel 1 are numbered 1-1 through 1-8,
and the inputs and outputs on communications channel 2 are numbered 2-1 through 2-8.
Settings associated with direct messages are automatically presented in accordance with the number of
channels provided in the communications module in a specific relay.
c) LOCAL DEVICES: DEVICE ID FOR TRANSMITTING GSSE MESSAGES
In a L90 relay, the device ID that represents the IEC 61850 GOOSE application ID (GoID) name string sent as part of each
GOOSE message is programmed in the
SETTINGS

PRODUCT SETUP

COMMUNICATIONS

IEC 61850 PROTOCOL

GSSE/GOOSE CONFIGURATION

TRANSMISSION

FIXED GOOSE

GOOSE ID
setting.
NOTE