Inter-Relay Communication Actual Values - GE D90 Plus Instruction Manual

CHAPTER 6: COMMUNICATIONS

Inter-relay communication actual values

PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
If the application is different for a channel pair (channels 1 and 2), then the channels are
treated independently and provide 96 inputs and outputs per channel.
Select one of the redundancy values in cases where redundancy is important.
Redundancy works on channel pairs (1 and 2). To enable redundancy for a channel pair,
both channels 1 and 2 must be set to the same application setting and redundancy
specified. Otherwise, the channels are treated independently. If channel redundancy is
enabled, then channel 1 becomes the primary channel and channel 2 the secondary
channel. In the event the primary channel fails, the data is accepted from the channel
pair twin (channel 2).
In redundancy mode, the secondary channels become dormant and report their direct
input states as off. In this case, only the primary channel is active and the use of the
secondary channel operands is not recommended. You program all logic to use the
primary channel operands when using redundant mode. In redundancy setting mode,
the channel 1 direct inputs and outputs are transmitted and received by both channels
when the IEDs are configured in a redundant ring. This provides a greater level of
security if one of the rings become disconnected. Use this mode when interfacing with
UR-series devices.
Inter-Relay Baud Rate
Range: 64 kbps, 128 kbps
Default: 64 kbps
This setting selects the baud rate for each inter-relay communications channel. All
interconnected devices must use the same baud rate for communications to operate
properly.
Protocol Encoding
Range: Default, G.703 Octet Internal Clock, G.703 Octet External Clock, G.703 Internal
Clock, G.703 External Clock, Diff. Manchester, C37.94 Internal Clock, C37.94 External Clock
Default: Default
For RS422 communications, only the "Default" value is available. For channels with G.703
communications, the "Default," "G.703 Internal Clock," "G.703 Octet Internal Clock,"
"G.703 External Clock," and "G.703 Octet External Clock" values are available. For
channels with fiber communications, the "Default," "Diff. Manchester," "C37.94 Internal
Clock," and "C37.94 External Clock" values are available.
The "Default" value defaults the communications to a connection in a higher order
system as shown in the table.
Table 12: Default value encoding
Protocol encoding
Octet timing
Timing
Fiber protocol
When an internal value is selected, the inter-relay communications card supplies the
clock for communications. When an external value is selected, the clock is supplied by
the external device connected to the inter-relay communications card.
The inter-relay actual values provide diagnostics to troubleshoot the inter-relay card when
there is a problem. These values are useful for the factory and the user if the inter-relay
card is not functioning properly. Each fiber transceiver contains a digital diagnostic
monitoring interface (DDMI) that provides the transceiver actual values.
Channel type
G.703 Fiber
Enabled N/A
External clock External clock
N/A C37.94
INTER-RELAY COMMUNICATIONS
RS422
N/A
N/A
N/A
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