IEC 61850-7-4 defines InRef as CDC ORG, which include setSrcRef and setSrcCB. Both are defined as writable, allowing configuration changes during runtime. Additionally, intAddr in InRefs(internal IED addresses)are used to map to ExtRefs.
However, the standard currently lacks clarity and robust mechanisms for reliable dynamic source switching, leading to significant interoperability and operational challenges during implementation.
If an IEC 61850 client writes to InRef.setSrcRef or InRef.setSrcCB independently, a transient inconsistent state can occur. For example, if a GOOSE message arrives during this partial update (e.g., setSrcRef is updated but setSrcCB is not yet, or vice versa), this can lead to incorrect input signal processing by the IED causing data loss, or application malfunction, posing a significant risk to reliability in critical applications.
Furthermore, it is unclear whether IEC 61850 clients are currently expected to write corresponding manufacturer-specific internal addresses to intAddr within InRef during source switching operations, alongside setSrcRef and setSrcCB.
Proposal
Implement a mechanism similar to the "confEdit" used for Setting Groups to enable the switching of the recieving source reference in InRef. This would allow setSrcRef and setSrcCB (and potentially other related InRef attributes) to be written first and then switch via a single operation. This ensures that the IED's input configuration always transitions between valid, consistent states.
intAddr in InRef shall be treated like sAddr and managed by IED internally. When user confirms the switching via "confEdit" IED shall internally switch or manage the intAddr to the corresponding matching source reference and source CB from the ExtRef. This avoids Client to deal with intAddr which is the case today.
Discussion
Created
Status
Editor Group:
Propose to set to Future Improvement due to:
Multiple use cases for dealing with ORG for testing have been assigned to the TF IEC 61850-10-3 Ed2.
Addtionally, the TF IEC 61850-90-20 is considering the redundancy use case when GOOSE and SMV are subscribed.
Finally, the TF IEC 61850-7-500 is considering the dynamic source switching based on topology change.
The conclusions of the different TF will be considered in a later version of the standard for clarifying the usage of ORG CDC.
19 Dec 25
Approval (Future Improvement)
IntAddr is defined as an SP functional constraint, and in fact, all elements within the ORG are defined as SPs. Neither IEC 61850-7-1 nor 7-3 states that only testEna is expected to be written in runtime. This is the primary reason why dynamic InRef Source Switching can currently be interpreted as permissible. If this behavior is not intended, it should be explicitly stated to prevent misinterpretations.
Furthermore, it's not clear from standard why intAddr is modeled as a Data Attribute while sAddr is not modeled as a Data Attribute, especially since both are manufacturer-specific internal addresses and intended for tool-only use. It will be good to add the purpose in the defintion of IntAddr DA.