Instruction manual

12 i .LON 100 e3 Hardware Guide
Table 1.2
i .LON 100 Server GSM Modem Connections
GSM Modem DB 9
Pin
i .LON 100 Screw
Terminal
Enclosure Marking
1 Not connected N/A
2 Pin 23 RXD
3 Pin 24 TXD
4 Not connected N/A
5 Pin 25 GND
6 Not connected N/A
7 Pin 21 RTS
8 Pin 22 CTS
9 Not connected N/A
In order to connect M-Bus devices to an i .LON 100 server, you will need a level
converter. This level converter should be connected to the RS-232 interface of the
i .LON 100 server and to the M-Bus devices. This converts the M-Bus signals to
RS-232 signals and supplies the M-Bus devices with power (like the Echelon Link
Power Transceivers).
Depending on the number of M-Bus devices you are going to connect to the
i .LON
100 server, different classes of level converters are available. There are
converters that can drive only 3 M-Bus devices, and there are converters that can
drive 20, 60, or as many as 250 devices. Examples and more information on
these level converters can be found at the following websites:
• www.relay.de
(Level Converter PW3, PW20, PW60)
• www.stv-automation.de
(BIALON MPW-20 M-Bus)
• www.hydrometer.de
(HYDRO-CENTER 25, 60, 250)
For more information on the M-Bus, refer to the M-Bus User Group at www.m-
bus.com.
If the RS-485 and EIA-232 ports are physically connected to a device other than a
GSM modem or an M-Bus device, a special custom software driver must be
provided by Echelon to support the intended application and enable
communications over the port. Check Echelon’s website at www.echelon.com
for
availability.
Figure 1.5 shows the EIA-232 and RS-485 port terminals (circled in red).