The information is of point-to-point type which means that there is only one signal connected to the function block input.
The default value of the GOOSE receiver blocks output (OUT) is FALSE (0) in case there is a communication error. This handling is applicable for all signal types (binary, double binary and floating point). In addition to the default value handling, value output signal automatically carries validity information to the application function blocks. Validity information can be used in application by adding the quality function blocks.
In communication disturbance cases, GOOSE receiver blocks use default values. Application function blocks using these signals have their own handling for propagated quality information and fail-safe functionality, especially when receiving analog type of data. Exact fail-safe functionality must be checked from the function block description in the technical manual.
If one relay application function block input receives several signals from several protection relays, the input value is calculated in OR or AND operation (configured in the Application Configuration tool) from several inputs. In this case, one default signal is treated as logical FALSE (0), but the other signals can keep the function block input value active. It works similarly as the traditional galvanic signal wires connected between protection relays. The advantage in the GOOSE-based signalling is that the application always detects faulty connections, which is not the case with the Normally Open (NO) type of physically wired galvanic contacts.
In all cases, however, a separate alarm event is always generated by the GSELPRT1.Alm data object for IEC 61850 event clients.
GSELPRT1.Alm can also be used on the application side as an input in the Signal Matrix Tool's Binary Outputs sheet (signal GSELPRT ALARM). For example, it is possible to change the setting group in case one or several protection relays are disconnected from the network.