Westermo GD-01 - Manual (Page 3)

3 6196-2211
Functional description
The GD-series of modems are modem for wireless data transmissions over the public
GSM network. The GSM-modem can be used to link PLC:s, data loggers, security and
surveillance systems or for data acquisition.
The GSM services supported by the Westermo GD-modems are Circuit Switched Data,
Fax, SMS and GPRS. A data communication link can be established to another
GSM modem, to an analogue modem or to a digital ISDN adapter. The protocol
used when connecting to an analogue modem is V.21, V.22, V.22bis, V.23, V32 or V.34.
The protocol used when connecting to an ISDN adapter is V.110. A connection can be
established either via AT-commands (ATD…) or via the RS-232 signal DTR. The DTR
connection is made to a preconfigured number. The unit can send and receive FAX
according to Fax Class 2 Group 3. SMS messages can be transmitted or received.
A SMS send session can be initiated by either an AT command or by a positive
transition of the DTR signal. Sending and receiving of packet data is possible with
the GPRS service.
The GD-xx series of GSM modems is available in two versions:
the GD-01 and the GD-02.
Wireless connection
to GSM network
SMA
connector
RF
Interface
SIM
card
RS-232
driver
Isolated
power supply
LED:s
GSM
Engine
Serial data
12–36 V DC
9-pos
D-sub
2-pos
screw
connector
5-pos
screw
connector
GD-01: