The protection relays are capable of vertical communication between the protection relay and monitoring and control systems (clients) such as PCM600 or ZEE600. Each protection relay can communicate to five separate clients to receive events, read or write data (an active PCM600 connection is considered to be a client). The protection relay can report data in either buffered or unbuffered mode and execute direct or select-before-operate control sequences according to the control commands sent by the client.
The protection relays are also capable of horizontal or peer-to-peer communication. They can be programmed to publish (send) information to and subscribe (receive) information from other devices according to IEC 61850-8-1 and IEC 61850-9-2 LE or IEC 61869-9.
IEC 61850 standard Edition 2 increased several identification string lengths which affects communication engineering and interoperability. Table 1 lists the identification length values to be considered especially with third-party tools. ABB tools generally check the length values.
| Object | Edition 1 length | Edition 2 length | Description |
|---|---|---|---|
| IED name | 28 (32-4) | 60 (64-4) | Excluding the longest LD name length of 4 characters |
| Report control block name | 14 | 30 | Without a two digit RCB instance number |
| Data set name | 32 | 32 | |
| RptID | 65 | 129 | Report Identifier |
| GoID | 65 | 129 | GOOSE Identifier |
| MSVID | 65 | 65 | Multicast Sampled Value Identifier (length as in 61850-9-2 LE) |
|
Control Block |
Maximum data sets |
Maximum length |
Description |
|---|---|---|---|
|
GoCB |
8 |
120 data objects or attributes in total 80 data objects or attributes per data set |
The sending GOOSE data sets can have in total 120 data objects or attributes in the GOOSE data sets. To minimize the message-handling load in the receiving and sending protection relays, it is recommended to limit the data object and attribute amount to 20 per data set. |
|
RCB |
27 |
Edition 1: 256 data attributes Edition 2: When the data attribute level is used, maximum 80 data attributes can be configured per data set. When the data object level is used, maximum 80 data objects can be configured if the limit of 300 attributes per data set is not reached before that. Structured data objects contain more data attributes. |
The recommendation is to use data objects when creating reporting data sets. The maximum number of reporting data sets is affected by the used GOOSE data sets. The number of data sets is shared with GOOSE meaning that therecan be minimum 21 data sets for reporting. |
|
SVCB |
1 |
16 and 48 data attributes for the IEC 61850-9-2 LE and IEC 61869-9 profiles respectively. |
The sending sampled value data set has a fixed set of 16 data attributes, as defined in IEC 61850-9-2 LE, with four current and four voltage measurement values with corresponding quality attributes. When the IEC 61869-9 profile is used, the dataset can have a maximum of 48 data attributes which can be configured by the user according to the target application. Every measurement value must be followed by its respective quality attribute. |