Echelon SmartServer 2.2 - Manual (Page 285)

286 Using the SmartServer as Network Management Tool
template used by the Modbus device.
You can edit the unit strings in the data point's Configure - Data Point
Web page. To open this Web page, click the General option above the
navigation pane on the left side of the SmartServer Web interface, and
then click the data point. The Unit String property is located in the upper
portion of the Web page.
This property is only displayed in Driver mode; it is not displayed in
General mode.
Poll Rate Displays the frequency in which the SmartServer polls the data point. The
recommended minimum poll rate is 30 seconds; the maximum poll rate is
1 second. Setting this value to 0 turns off polling. The default poll rate
for Modbus data points is 10 seconds.
This property is only displayed in Driver mode; it is not displayed in
General mode.
Description Displays a description of the Modbus data point. This description has no
effect on network operation, but you can use it to provide additional
documentation for as-built reports.
This property is only displayed in Driver mode; it is not displayed in
General mode.
Tip: You can configure the data points on a Modbus device by creating one data point, and then
duplicating it (right-click the data point and click Duplicate on the shortcut menu) to create the
required number of data points. This enables the start addresses of the Modbus data points to be
calculated automatically. You can then use the Overview - Data Points Web page to modify the
start addresses, functions, format descriptions, and names of the duplicate Modbus data points
accordingly. See Creating a Duplicate Dynamic Data Point in Chapter 4, Using the SmartServer
Web Interface, for more information on duplicating data points.
7. Click Submit to save any changes.
Designing an M-Bus Network
You can design and operate an M-Bus network with the SmartServer. The M-Bus (Meter Bus) is a
European standard for remote reading of meters. It can be used for supply meters, as well as sensors
and actuators.
The SmartServer has an M-Bus driver that uses the M-Bus protocol (EN 1434-3) to communicate with
M-Bus devices on the network. On an M-Bus network, the SmartServer functions as the master to the
slave M-Bus devices. The M-Bus driver on the SmartServer conforms to the following serial
parameters: 9600-8-None-1-None.
Designing an M-Bus network entails creating and configuring M-Bus channels, devices, and data
points. After you design an M-Bus network, you can use the SmartServer applications to read and
write to the M-Bus devices. For more information on the M-Bus protocol, go to
www.m-bus.com .
Creating and Configuring M-Bus Channels
The SmartServer can interface with slave M-Bus devices on 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.