CHAPTER 6: COMMUNICATIONS
INTER-RELAY COMMUNICATIONS
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
159
Figure 144: Inter-relay communications commands
The following teleprotection command is available.
Clear Teleprotection Counters
This command clears the number of teleprotection lost packets count.
Inter-relay communications
The inter-relay communications settings are used to configure inter-relay communications
for direct inputs and outputs and teleprotection inputs and outputs.
Select the
Settings > Communications > Inter-Relay
menu item to open the inter-relay
communications configuration window.
Figure 145: Inter-relay communications configuration settings
The following settings are available for each inter-relay communications channel.
Inter-Relay Application
Range: None, Direct I/O, Teleprotection, Direct I/O Redundant
Default: None
This setting selects the inter-relay communications application for each channel.
This setting can be selected as “Direct I/O”, “Direct I/O Redundant”, or “Teleprotection” to
enable direct inputs and outputs. If a channel is set to “None”, then that transmitter’s
output is disabled.
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.
One of the redundancy values should be selected 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 will be 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. The user should 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