CHAPTER 3: IEC 61850 COMMUNICATION
The name of the SCL Log file is "urscl.log". This file is stored in the UR in a RAM file system, thus the file content is volatile
and is lost when the UR is powered off.
3.9.2 SCL file storage on UR
To provide high reliability storage of the CID file in the UR, two copies are maintained in non-volatile memory. One is the
working copy and the other is the backup copy. The working copy is the configuration that is currently active in the device,
and the backup copy is the last known good copy. Thus, if a CID file storage operation is not completed properly, due to a
loss of control power for example, the last good CID file is still be available for use. If a CID file transfer is halted partway
through, or if the UR rejects a transferred CID file, the working file settings are still in effect.
ICD and IID files obtained from a UR are created on demand when requested by a client, and thus are not stored in the UR
file system. The IID file is always up to date at the time that it is requested.
3.9.3 Generation Of CID files
CID files can be produced by EnerVista, a third party Subsystem Configuration Tool (SCT), or even by editing the XML file
manually using a text editor. It is recommended that CID files not created by EnerVista that are intended for use in a UR, be
imported into EnerVista to check for errors prior to being transferred to a UR.
3.9.4 Schema version used by UR/EnerVista
All IEC 61850 SCL files, including ICD, IID, and CID files are formatted as XML and follow some version of the IEC 61850 XML
UR firmware 7.4 uses IEC 61850 Edition 2, SCL schema version "2007", revision "B", release 1, date 2014-07-18.
It is very important that all CID files sent to the UR are well-formed XML, and are valid according to this IEC schema version.
Note that the UR itself does not contain a schema validator. Validate the CID file schema on a computer before the file is
transferred to the UR. While the UR performs a number of parsing and data validation checks as described as follows, send
only syntactically valid files to the UR.
3.9.5 CID file processing steps
When a file transfer protocol is initiated to send a CID file to a UR, the UR remains in its current operational state until the
completion of the file transfer and file validation processes. That is, if the IN SERVICE indicator is on, the UR remains in
service, if the IN SERVICE indicator is off, the UR remains out of service.
Upon completion of the file transfer, the UR parses the file and performs a number of validation checks. First, the file is
parsed and the data is extracted and stored in internal data structures. To accomplish this, each element and attribute is
parsed and the associated data is converted for local storage. Since the file can contain multiple IED elements, the UR
locates the "target" IED element and then extracts the appropriate information. See the
Configured IED description (CID)
section on page 3-239 for a description of the CID file contents.
If the file is found to be valid, the UR takes itself out of service (the IN SERVICE indicator turns off if it is currently on), and the
new configuration is applied. This includes all IEC 61850 configurations in the standard part of the CID file, and the UR
settings in the Private settings element of the CID file. If the file is valid, the UR returns to service (the IN SERVICE indicator
turns on) if it was in service before the file validation. The CID file import is complete.
If the file is found to be invalid, the existing UR settings remains in place.
In either case, check the urscl.log file to determine if there were any issues found with the CID file.
3.9.6 SCL log file format and examples
The urscl.log file is a simple text file that contains a number of individual entries describing the CID file validation process.
Each entry has a timestamp and a description. The entries are categorized as follows:
INFORMATION — This entry is for information purposes and does not indicate a problem with the CID file
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