RTAC R151 Technical Note

With the addition of firmware version R151-V0 to the RTAC product line, the
following are some notes and additional comments about new additions or
changes in the firmware. These items are compiled from the release notes found
in Appendix A: Firmware and Manual Versions of the ACSELERATOR RTAC®
SEL-5033 Software Instruction Manual. Please note that this document does not
discuss each release note, but rather just those with additional context or conver-
sation points. This information can also be found in the SEL-5033 instruction
manual in the appropriate sections for the new or modified behavior.
Some new features or enhancements to existing features in R151-V0 include the
following:
➤ Added support for 3U SEL-3350 automation controller hardware.
➤ Added OPC UA client protocol.
➤ Enhanced the Connected IED tools in the web interface to add an
online protocol dissector for debugging serial or Ethernet communi-
cations to client and server devices.
➤ Enhanced the Sequence of Events log to store 500,000 records.
➤ Enhancements to the Check IED configuration functionality pro-
vided by SEL protocol clients and servers.
➤ Increased the Recording Group custom channel limit from 128 to
512 BOOL quantities.
➤ Improved the frequency tracking step response performance on
voltage input startup for SEL-2245-42 AC protection modules.
➤ [Cybersecurity Enhancement] Support for a Restricted BIOS with a
reduced set of functionality that provides an enhanced security
posture.
➤ [Cybersecurity Enhancement] Removed support for TLSv1.1 for
SSL/TLS connections established by protocols, HTTPS connections
to the web interface, and connections on TCP port 5432.
A collection of IEC 61850 enhancements is also included with R151-V0,
including the following changes:
➤ Added support for functional naming for MMS client and GOOSE
receive.
➤ Added support for LGOS logical nodes for GOOSE receive
messages.
➤ Enhanced MMS client to support collection of DPL, LPL, and VSS
common data classes.
➤ Enhanced MMS client to support the set point functional constraint
for common data classes CUG, ENG, ING, ORG, SPG, and TSG.
➤ Enhanced MMS server to support the set point functional constraint
for common data classes ASG, CUG, ENG, ING, ORG, SPG, and
TSG.
➤ Enhanced MMS server to support LTIM and LTMS logical nodes.
➤ Enhanced MMS server to support local-remote functionality.
➤ Enhanced GOOSE to support simulation mode.

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ACSELERATOR RTAC enhancements include the following:

➤ Added Modification Type column to main menu.
➤ Added support for logging of ACD, ACT, and ENS tag types in the
Tag Processor.
➤ Added support for IIoT libraries supporting MQTT, HTTP, and Web
Socket communications supported by XML and JSON formatting.
The following are additional comments on new features and changes in the RTAC
product line.

Addition of OPC UA Client Protocol

Firmware version R150-V0 added support for OPC UA (Open Platform Commu-
nications, Unified Architecture) server, and with the release of R151-V0. a corre-
sponding OPC UA client protocol is now supported in SEL-3350 and SEL-3555
projects. In these projects, as many as ten OPC UA clients can be added. OPC
UA client is a cost-adder option for the SEL-3350, SEL-3555, and SEL-3560
RTACs, and it can be added in the field. Features of the OPC UA client protocol
include the following:
➤ Automatic tag browsing of an OPC UA server that can be communi-
cated to from the ACSELERATOR RTAC installation; no physical
RTAC is required for this functionality to operate.
➤ Following the tag browsing operation, a simple interface to select
which tags the RTAC should poll from the server.
➤ An option to insert OPC UA variables in either structured (a dot-sep-
arated tag name representing the entire path to the variable) or
unstructured (one single, unified tag name that can be customized to
be a far shorter name).

Connected IED Enhancements, Including Online Protocol Dissector

R151 adds a real-time communication status display for client and server devices.
A green status indicates successful communications (Offline = FALSE), red sta-
tus indicates failed communications (Offline = TRUE), and gray indicates a dis-
abled device (ENO = FALSE).

For SEL-3350, SEL-3555, and SEL-3560 RTACs, an online packet dissector is

also available from the Connected IEDs page. This tool supports online trouble-
shooting of device communications by providing real-time decoding of Ethernet
and serial variations of devices of the following client/server protocols:
➤ DNP
➤ Modbus

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➤ SEL
➤ IEC 60870-5-101/104
➤ IEEE C37.118 Synchrophasors
➤ L&G 8979
➤ CP2179
➤ IEC 61850 MMS and GOOSE
The interface allows for application of display filters (matching the same syntax
used by Wireshark) as well as facilities to start and stop the capture and to down-
load a pcap file of the traffic for offline troubleshooting.

Sequence of Events Log Stores 500,000 Records

On the SEL-3350, SEL-3555 and SEL-3560 RTACs, an enhancement was made
to the SOE logging capabilities to increase the maximum number of stored events
from 30,000 to 500,000. This allows for far more capable historical context in the
SOE log and IED SER collection capabilities of the RTAC platform.

SEL Protocol Check IED Configuration Enhancements

The Check IED configuration features supported by SEL clients have been
enhanced to provide some basic historical logging of previously detected changes
as well as automatic notification of newly detected changes via an SEL server
connection to a monitoring application. If a change in an IED’s settings is
detected by an SEL client, it will now write that event to a report file in the
RTAC’s file manager, storing time stamps and SHA256 hashes of the last ten
change events.

[Cybersecurity Enhancement] Restricted BIOS for Improved Security

When R151-V0 (or one of the associated point releases of R148-V6, R149-V3 or
R150-V2) is loaded onto an SEL-3555-2 or SEL-3350 RTAC, a BIOS update will
occur (the update can take as long as 10 minutes). The new updated Restricted
BIOS has several features removed (such as remote management on the
SEL-3555-2) in the name of improving security and reducing the need for future
BIOS updates as vulnerabilities are discovered in those unused features. Of addi-

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tional note with the Restricted BIOS is that it contains no user settings and cannot
be entered by an end user via a key press at startup. Version 12.5.49152.263 is the
updated version for the SEL-3555-2/SEL-3560-2 and version 11.2.49152.142 is
the update for the SEL-3350.

[Cybersecurity Enhancement] Removal of TLSv1.1 for SSL/TSL Connections

TLSv1.1 has been deprecated. The RTAC platforms support the TLS v1.2 stan-
dard. The removal of this encrypted communications method from the RTAC
enhances the security posture of the product. External applications using TLS
connections to the RTAC (ACSELERATOR Team® SEL-5045 Software,
™ ™
ACSELERATOR Diagram Builder SEL-5035 Software, SEL Blueframe , the
Data Management and Automation (DMA) application suite, etc.) may require
updates to preserve compatibility with R151 firmware.

IEC 61850 Enhancements

R151-V0 includes a variety of IEC 61850 enhancements. For additional details
on these features, see Section 2: Communications in the SEL-5033 Instruction
Manual. New functionality includes support for the following:
➤ Automatic generation and updating of LGOS logical nodes for
received GOOSE messages. The statistics are consistent with LGOS
statistics available from SEL relays. To have ACSELERATOR Archi-
tect® SEL-5032 Software automatically generate LGOS nodes, use
CID class file version 8 or later.
➤ Simulation mode for GOOSE receive messages. The
CFG.LPHD.Sim data object (which enables or disables simulation
mode) can be managed via the logic engine or the MMS server inter-
face to turn simulation mode on or off. Simulation mode is available
if the CFG.LPHD.Sim data object exists in the server data model
regardless of the CID class file version. CID class file version 8 will
be the first CID file to automatically include CFG.LPHD.Sim in the
RTAC data model by default.
➤ Automatic generation of LTIM and LTMS logical nodes, which pro-
vide status information about the RTAC system clock and synchroni-
zation status. These data will only be automatically populated when
LTIM and LTMS are included in the CFG logical device. CID class
file version 8 will be the first CID file to automatically include LTIM
and LTMS in the RTAC data model by default.
➤ Support for local/remote control. This functionality will consider the
orcat value received by the MMS server when the logical node or
logical device is in local mode.
➤ Support for the set point functional constraint in both the MMS
server and client. This adds support for tags with data types ASG,
CUG, ENG, ING, ORG, SPG, and TSG. There is no dependency on
elements or attributes in the CID file or CID class file version.
➤ Support for functional naming in MMS client and GOOSE receive.
Functional naming will be used when the supportsLdName attribute
in the client services element in the RTAC’s CID file is set to True.
When this attribute is set to True, MMS clients will create function-
ally named tags if functionally named data is in the server’s CID file.
If the server contains no functionally named data, product naming
will be used. For GOOSE receive when functional naming is enabled

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and the publishing device has functionally named data, the functional
name will be used in the ACSELERATOR RTAC. If the publishing
device does not have functionally named data, product naming will
be used instead of the index-based naming used prior to R151. Func-
tional naming is disabled by default in CID class file version 8.

SEL-3505-3 Firmware Compatibility Updates

SEL-3505-3 units manufactured after November 11, 2022, are only compatible
with firmware revisions R148-V6, R149-V3, R150-V2, and R151-V0 or later.
This is because a hardware component change in the SEL-3505-3 that requires
updated firmware to run the new hardware port. Customers with firmware locks
on the SEL-3505-3 must update their special specs to allow ordering of new
SEL-3505-3 hardware.

Cybersecurity Fixes to RTAC Web Interface

R151-V0, along with all associated point releases (R147-V6, R148-V7,
R149-V4, and R150-V2), includes a collection of bug fixes to resolve vulnerabil-
ities in the RTAC web interface. These corrections prevent an authenticated
attacker from possibly exploiting various web functions that could cause infor-
mation leakage (user credentials, operating system files, etc.).

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RTAC R150 Technical Note Date Code 20221108