ProSoft Technology PLX8X-MNET-61850 - Manual (Page 168)

Reference PLX8x-MNET-61850 ♦ Communication Gateway
User Manual Modbus TCP/IP to IEC 61850
Page 168 of 228 ProSoft Technology, Inc.
May 14, 2014
Configured GOOSE messages for an IED are not re-subscribed upon a
reconnect. There is no need, because GOOSE messages are of an EtherType
packet, not an IP packet. GOOSE messages are addressed by MAC address,
not IP address. (Essentially it is a broadcast message.)
Configured Reports for an IED return to a Must try to Enable state, and follow the
startup sequence.
If MMS Reset (meaning the stream is out of step) is issued by the gateway or the
IED, then the gateway issues a disconnect and reconnects to the IED. If the IEC-
61850 driver receives a short packet (short MMS read) then it issues a MMS
Reset.
6.5 Processing the Commands
The command processing options are:
Continuous polling
 Messages will be issued to the server each time the command is next on the
polling list.
Timed polling
 Commands will issue a message when the time has expired and the
command is the next command in the polling list.
Data change event
 Commands will be loaded into a queue when any value in a tag mapped to
the command changes. The queue is always checked before processing the
scan list giving event commands a higher priority. IEC 61850 GOOSE data
has priority over any other command processing.
Client tag mapping is command based. Each command has one tag mapped to
the Modbus registers being written or read by the Client. When reading registers
from a server, the data returned in the response is placed in tags in the tag
database. When writing registers to a server, the data is taken from tags in the
tag database. This tag mapping is done at the individual command level. The
tags are mapped within ProSoft 61850 Configuration Manager.