GE D90 Plus Instruction Manual page 280

CONTROL ELEMENTS
272
RX1, RX2, RX3, RX4
Range: any FlexLogic™ operand
Default: OFF
These settings select FlexLogic™ operands to represent the permission receive signals
for the scheme. Contact inputs interfacing with a signaling system are typically used.
These settings must be used in conjunction with the loss-of-guard signals, otherwise the
scheme will not unblock and thus fail to operate. These settings are used as follows.
– In single-bit applications,
– In two-bit applications,
– In four-bit applications,
Loss of Guard 1, Loss of Guard 2, Loss of Guard 3, Loss of Guard 4
Range: any FlexLogic™ operand
Default: OFF
These settings select FlexLogic™ operands to represent the loss-of-guard receive signals
for the scheme. Contact inputs interfacing with a signaling system are typically used.
Each loss-of-guard signal must correspond to the same receive signal from the same
communications channel (that is,
communications channel, and the same for channels 2, 3 and 4, if used). These settings
are used as follows.
– In single-bit applications,
– In two-bit applications,
must be used.
– In four-bit applications, all receive and loss-of-guard signals must be used.
Events
Range: Enabled, Disabled
Default: Enabled
This setting enables and disables the logging of directional comparison unblocking
scheme events in the sequence of events recorder.
The directional comparison unblocking scheme logic is shown below.
must be used.
RX1
and must be used.
RX1 RX2
through must be used.
RX1 RX4
and
RX1 Loss of Guard 1
and
Loss of Guard 1 RX1
with
Loss of Guard 1 RX1
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 7: PROTECTION
must be from the same
must be used.
and with
Loss of Guard 2 RX2