ProSoft Technology PLX8X-MNET-61850 - Manual (Page 174)

Reference PLX8x-MNET-61850 ♦ Communication Gateway
User Manual Modbus TCP/IP to IEC 61850
Page 174 of 228 ProSoft Technology, Inc.
May 14, 2014
6.6.6 Report Control Block BRCB (Clause 14)
Buffered Report Control Block (BRCB)
A Buffered Report Control Block (BRCB) is associated with a DATA-SET. BRCB
data is queued up, or buffered, in the IED, and sent sequentially to the connected
IEC-61850 Client. The size of the buffer is defined by the IED. BRCB is used so
that data will not be lost due to communication control or loss of connection.
There are procedures required around the reporting, and the IED may only report
to one Client.
Unbuffered Report Control Block (URCB)
An Unbuffered Report Control Block (URCB) is associated with a DATA-SET.
URCB data is sent immediately to the connected IEC-61850 Client. If the
transport data flow is not fast enough to support the movement of this data, some
may be lost. The IED can have multiple instances of the URCB data, and
manages the separation of the instances to the IEC-61850 Clients.
6.6.7 Control (Clause 17)
There are 5 types of control models defined:
 Status-only
 Direct-with-normal-security
 Select Before Operate SBO-with-normal-security
 Direct-with-enhanced-security
 Select Before Operate SBO-with-enhanced-security
Enhanced Security tends to be used only for high-voltage sites.
SBO includes a Select step, used to check that the control may be valid and to
eventually lock a resource.