$95 HD/LINKer - Invensys Rail

7.1 MODULE CONFIGURATIONS
Document No.: SIG-00-97-08 Version: C
SECTION VII
CIRCUIT CONFIGURATIONS
7-1
CIRCUIT CONFIGURATIONS
The HD/LINK module consists of independent Vital Parallel Input (VPI) channels, Vital Relay Output
(VRO) channels, and internal I/O channels.
The VPI channels are enabled to sense the state of relay contacts, while the VRO channels are
enabled to drive vital signaling relays. Internal input channels are enabled to sense the output of
other internal channels, and internal output channels are enabled to drive other internal input
channels.
The channels of an HD/LINK module can be configured to perform a variety of signaling functions
as described in the following paragraphs. HD/LINK module configuration is determined by the MCF
data stored in the External Configuration Device (ECD) of the interface connector.
7.1.1 Designation and Identification
In the following discussion, each HD/LINK module configuration is shown by a block diagram,
showing the interconnection and interrelationship between the configured channels. Within each
channel block, the type of channel and channel number are identified.
Included with each block diagram are two unique symbols that define the attributes of the
configuration: external and internal.
� The external symbol designates that the configured channels are connected to external vital I/O.
� The internal symbol designates that the configured channels interact only with internal I/O
events generated within one or more interconnected channels of the module.
In the graphic representation of a functional configuration, two numbers separated by a dash
identify each symbol. The first number corresponds to the assigned module number within the
group. The second number corresponds to the I/O channel used in the configuration.