Protocol Server Attachment To A Client; Several Identical Client Connections - ABB RELION Series Communication Protocol Manual

Section 3
Vendor-specific implementation
3.1.2
3.1.3
10
By default, instance 1 is always instantiated in the protection relay, but needs to be set
"On" to be activated. Since the protection relay's native IEC 61850 data model
restricts client limit to five, the protection relay can have only five client connections
in total, regardless of the protocols to which the clients belong. This includes the MMS
clients and other communication protocol clients.
Protocol instances are identified with numbers 1...5. There are different and unique
setting and monitoring parameters for each instance in the HMI menu. Instance
numbers can be freely used. However, it is recommended to use the instances in the
numerical order. For example, instance 1 is to be used if there is only one client
connection and instances 1 and 2 when there are two clients.

Protocol server attachment to a client

After its activation, an instance should be attached to the intended client.
If the client is in a serial connection, the instance must be attached to the intended
serial port.
In case of a TCP client, the instance must be first attached to the physical Ethernet port.
If there are several TCP client connections, the protection relay must be able to
distinguish between the clients. There are two setting parameters in an instance.
• Client IP: When the client makes the TCP connection, its IP address is checked.
This instance is given to the client with this IP address. It is also possible to use
the address "0.0.0.0" if no client IP address is to be defined. In this case, the
client's IP address is ignored.
• TCP port: This parameter can be used in conjunction with the Client IP address
setting, thus allowing only a certain IP address at a specific TCP socket port
number.

Several identical client connections

If several clients access the same protocol data, the client connections must still be
kept apart. Also the number of each instance used for each client must be noted so that
if there are problems with the communication, the line diagnostic data for instances
follows the same instance number rule.
In case of sequential event data transaction and a TCP client connection, it is essential
that a reconnecting client is given back the same instance to which it was attached
before disconnecting. This way, the event reading resumes from the point where the
client left off, provided that no event overflow has occurred while the client was
absent. If multiple client connections are used, the distinguishing between different
client connections must be ensured by using the Client IP and TCP port parameters.
1MRS758757 A
REC615 and RER615
Communication Protocol Manual