Saturday, June 30, 2012

Mismatch of ConfRev values in IED and SCL file

The issue of how can the values of ConfRev (configuration revision) in an IED be consistent with the configuration file during the lifetime of IED has been discussed may times. The final standardized solution is now discussed in the IEC TC 57 WG 10 task force “System Management”.

Here are some hints on the issue that help to understand what to do until we get a standardized solution.

Part IEC 61850-7-2 Edition 2 defines for GOOSE Control Blocks: ConfRev – configuration revision
The attribute ConfRev shall represent a count of the number of times that the configuration of the DATA-SET referenced by DatSet has been changed. Changes that shall be counted are:
– any deletion of a member of the data-set;
– Any adding of a member to the data-set;
– the reordering of members of the data-set; and
– changing the value of the attribute DatSet.
The counter shall be incremented when the configuration changes. At configuration time, the configuration tool will be responsible for incrementing/maintaining the ConfRev value. When configuration changes occur due to SetGoCBValues, the IED shall be responsible for incrementing the value of ConfRev.
If the value of DatSet is set through a SetGoCBValues service to the same value, the ConfRev value shall still be incremented.

Part IEC 61850-6 Edition 2 defines for GOOSE and SV Control Blocks:

“The configuration revision number of this control block; mandatory. It is recommended to increment it by 10000 on any configuration change, to distinguish this from online configuration changes [by services] leading to an increment of 1 only”


In the meantime you have to implement a work-around on your own, e.g., when you implement online changes (caused by services), then the build-in IED Tool (“online tool” in the IED) has to increment the ConfRev value by 1. If you implement a change in the SCL file that is used to configure the IED then you are recommended to READ first the current ConfRev value of the IED and increment by 10,000 and “overwrite” the current value in the SCL file before you re-configure the IED.

It should be specified in the PIXIT file how your IED works (as publisher and/or subscriber).

Please note the tissue 840 (quite new) in which you can read:

“The question, how dynamic changes done online (through the IED front-panel or through communication services) relate to changes made through configuration files and if these changes shall be allowed for real use is a different topic. There is currently a task force active dealing with system management - they will need to address details on how precisely dynamic changes shall be handled compared to static (through configuration) changes.”

In the following document you find also that the issue is well known:

See §2.2.9

There is still some work to be done – you are invited to get involved in the ongoing work of the WG 10 (Project “System Management”) to provide your input on the issue “Configuration Version Control”.

A special group of the German Mirror committee of IEC TC 57 has published a requirement document for IEC 61850 Engineering Systems:

“Anforderungen an IEC 61850 Engineeringwerkzeuge” [Deutsch]

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