Westermo TD-22 - Manual (Page 3)

4 6177-2203
Introduction
The Westermo TD-22 is an industrialised dial and leased line modem. This modem has been
developed to be used in industrial applications and has some features you would not expect to find on
a normal modem.
Terminal data rates of up to 19.2 kbit/sec can be handled using data compression and error
correction. Direct mode connections with the maximum line modulation speed of 2,400 bit/sec can
be made.
Lease line 2 and 4 wire connections can be made as well as multidrop half duplex V.23 connections.
The modem can also be used on ordinary twisted pair cables to provide long distance asynchronous
communications.
A watchdog facility continually monitors the power supply and internal hardware as well as the
operational software. In the event of a problem the modem automatically resets. This feature has
been included to make the unit more suitable for use in unmanned locations.
The TD-22 is available in two standard versions for power supply by 230VAC or 12-36VDC. Special
115VAC and 36-55VDC models are also available on request.
Westermo have implemented commands often left out of standard modems like &D to allow
hardware controlled dial out on receipt of a hardware signal and &A to prevent aborts on connection
when extra characters are received.
The TD-22 can handle 11 data bits and has a special 2 stop bit mode to allow the unit to be used in
applications many modems can’t handle.
The TD-22 has been designed with the engineer in mind, hence the extensive information on the
command set, S registers, DIP switched and error codes. We have endeavoured to include all
necessary information however if you need more please do not hesitate to call us.
Safety
This equipment should only be installed by professional service personnel. If the unit is intended for
permanent connection to mains supply, there should be a readily accessible
disconnect device (circuit breaker) incorporated into the fixed wiring.
All ports on this equipment are designed for connection to TNV circuits.
The mains connection is classified as excessive voltage
Description of the above classifications are given in EN60950:1992.