Echelon SmartServer 2.2 - Manual (Page 269)

270 Using the SmartServer as Network Management Tool
This property is only displayed in Driver mode; it is not displayed
in General mode.
Note: The actual poll rate for a data point is determined by
calculating the greatest common devisor of all the poll rates set for
the data point in the applications to which it has been added.
For example, if a Data Logger polls a data point every 5 seconds,
and an Alarm Generator polls the same data point every 7 seconds,
the SmartServer’s internal data server will poll the data point every
1 second.
Therefore, set poll rates in the SmartServer’s applications that are
the same for a given data point, or poll rates that are at least
multiples of each other.
For example, if a Data Logger polls a data point every 5 seconds,
and an Alarm Generator polls the same data point every 10 seconds,
the SmartServer’s internal data server will poll the data point every
5 seconds.
6. Click Submit to save any changes.
Connecting L
ON
W
ORKS
Data Points with L
ON
W
ORKS
Connections
You can create L ON W ORKS connections in the SmartServer tree or OpenLNS tree to bind the network
variables of L ON W ORKS devices that are in the same network. Creating L ON W ORKS connections with
the SmartServer is comparable to creating connections with OpenLNS CT. You select a hub network
variable in the OpenLNS tree and then select one or compatible target network variables in the same
network. Network variables must have the same type to be compatible. Once you create L
ON W ORKS
connection, the target data points will receive all updates from the hub (source) in the connection. This
process of connecting network variables is called binding, and the logical connections are thought of as
virtual wires.
L ON W ORKS connections created with the SmartServer always use Subnet/Node ID addressing. You
can use an OpenLNS application such as OpenLNS CT to select a different addressing mode such as
group or broadcast for L
ON W ORKS connections.
For more information on creating L ON W ORKS connections, see Creating L ON W ORKS Connections in
Chapter 4.
Designing a Modbus Network
You can design a Modbus network with the SmartServer. This entails creating and configuring
Modbus channels, devices, and data points. After you design a Modbus network, you can use the
SmartServer applications to read and write to the holding registers on the Modbus devices. For more
information on the Modbus protocol, go to
www.modbus.org .
Creating and Configuring Modbus Channels
The SmartServer can interface with slave Modbus devices on TCP/IP, RS-232, and RS-485 channels.
The RS-232 channel protocol is the Electronic Industries Association (EIA) standard for the
interchange of serial binary data between two devices. The RS-485 channel protocol is a data protocol
used for transmitting data over longer distances.
Creating Modbus Channels
To add a Modbus channel to the local SmartServer network, follow these steps:
1. Right-click the network icon, point to Add Channel, and then select Modbus.