IEC 61850 User Feedback Task Force

8-1 only maps what is defined in the ACSI.
The signature of the 7-2 SetDataValues is 1 (one) Reference. The mapping of SetDataValues therefore maps 1 (one) reference to 1 (one) MMS VariableAccessSpecification.

The "s" of values in ACSI SetDataValues is NOT determine by the usage of multiple References, but by the usage of multiple values that are needed to set a single FCD. "Values for all data attributes of A data object referenced by FCDA".

In other words: IEC 61850-7-2 also restricts the service SetDataValues to a SINGLE IEC 61850 reference.

Then we should evaluate changing 7-2 and 8-1. MMS supports the writes of multiple Variable Access Specifications and it is the same as writing a DataSet.

Remember that ACSI has an object-oriented approach. The SetDataValues service is associated to the GenDataObjectClass and not to the GenServer.

Background:
The requirement is to update multiple values in a schedule consistently.
Often only a subset of the schedule values may need to be updated, for example ValASG14 to ValASG48
Ideally the update should be done via a single message, with a single result.

Part 7.2 services appear to support two alternative methods but neither seems efficient.
- A single message with all the values whether they have changed or not
- One message per changed value

The original use case (from Japan) is short term planning within a day
A schedule is prepared a day ahead. The schedule execution starts as normal.
During the day something happens which means part of the schedule for the afternoon or evening needs to be changed.
As comment #5 - option 1: the entire schedule (maybe 96 values) must be re-written, or a series of messages sent to update individual values one by one.

An alternative modelling approach: the IED needs to support both the periodic schedule and one or more alternative, short schedules with a higher priority.
When needed the alternative schedule(s) are updated and enabled to temporarily override the base schedule.