ABB COM600 3.4, User Manual

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Attributes 5.4.
General about attributes 5.4.1.
In addition to item tags for process data (indications and commands), the OPC servers
and clients also provide some item tags for controlling the devices and retrieving status
information from them. These item tags are called attributes.
There are three categories of attributes: IEC101 Slave OPC Client attributes, IEC101
Channel attributes and IEC101 Device attributes. These attributes are described in the
following subsections.
Client attributes 5.4.2.
Table 5.4.2-1 Client attributes
Description Value or Value range/ Default Property / Para-
meter
The version information of the Protocol
Stack. Value: Version information Protocol Stack Ver-
sion
Channel attributes 5.4.3.
Table 5.4.3-1 Channel attributes
Description Value or Value range/ Default Property / Para-
meter
Basic
The state of the channel - whether it is in
use or not. When a channel is not in use,
no data can be transmitted on it, and no
data is received from it. The channel
attributes can be read as usual. Generally,
a channel must be taken out of use by
setting this attribute to 0 before the chan-
nel attributes can be written.
When a channel is stopped by setting the
In use attribute to 0, all data transmission
on the channel ceases. However, before
that, the protocol stack executes to the
end all on-going data transactions. For
example, the of the station in turn is com-
pleted.
0 = Not in use, the channel
communication is stopped.
1 = In use.
In use
Modem Signal
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Station Automation COM600 3.4
1MRS755382
IEC 60870-5-101 Slave (OPC) User's Manual