CommFront CVT-485A-1 User manual

Revision: 2.1 www.CommFront.com Page 1 of 4
Industrial Port-Powered RS232 

RS485 Converter
(Part Number: CVT-485A-1)
http://www.CommFront.com
Revision: 2.1 www.CommFront.com Page 2 of 4
■ INTRODUCTION
The CVT-485A-1 is a slim, rugged, industrial grade, port-powered RS-232 to
RS-485 onverter, whi h an be used to onvert any standard RS-232C port into a
two-wire half-duplex RS-485 port and vi e versa. It supports multi-drop RS-485
networks and an be used to ommuni ate with one loop of up to 128 units of
RS-485 devi es. The unit features very high power effi ien y (less than 8mA) and
supports data dire tion auto-turnaround. It omes with a 5-way terminal blo k
whi h an be atta hed to the onverter se urely without using s rews and nuts,
and the innovative sele table 120-Ohm end-of-line terminator design makes the
termination easier than ever before, thus making the unit an ideal solution for
qui k installation and spa e-restri ted appli ations.
■ FEATURES
•Port-powered with higher sensitivity and higher power effi ien y.
•Designed for qui k installation and spa e-restri ted appli ations.
•Supports 128 nodes of RS-485 devi es.
•Operates reliably from 300 to 115,200 baud.
•Industrial grade en losed in a rugged, rustless ABS housing.
•Plug and play (hot-pluggable, data format auto-sensing and self-adjusting).
•Data dire tion auto-turnaround, no software drivers or flow ontrol is required.
•Operating temperature: -40ºF to 185ºF (-40ºC to 85ºC).
•Built-in 600W surge prote tion, 15kV stati prote tion and ir uit prote tion.
•Built-in sele table 120Ω terminator for system reliability and easy installation.
•Rugged 5-way terminal blo k requires no s rews and nuts.
•Surfa e Mount Te hnology manufa tured to RoHS and ISO-9001 standards.
•Safety: Stri tly ertified by TUV (Cert No. SG-CE-090012).
•5-year manufa turer’s warranty.
■ SPECIFICATIONS
Compatibility: EIA/TIA RS-232C standard and RS-485 standard
Power Sour e: Port power from RS-232 data line
Current Consumption: Less than 8mA
Baud Rates: 300 to 115,200bps (auto-sensing and self-adjusting)
Distan e: RS-232 side: 16ft (5m); RS-485 side: Depending on
power from RS-232 port, will transmit up to 4000ft
(1.2km) at 19,200bps
Conne tor: RS-232 side: DB-9 Female; RS-485 side: 5-Way Terminal
Blo k
Max. number of drops: 128
End-of-Line Terminator: 120Ω (built-in, sele table)
Surge Prote tion: 600W
Stati Prote tion (ESD): Up to 15KV
Dimensions (H x W x
D):
0.63 x 1.3 x 2.7 in (16 x 32 x 69 mm) (with termination
board)
Weight: 1.0 oz (28 g) (with termination board)
Operating Temperature: -40ºF to 185ºF (-40ºC to 85ºC)
Operating Humidity: Up to 90% RH (no ondensation)
Industrial Port-Powered RS232/RS485 Converter
Part Number: CVT-485A-1
Communi ations made easy

Revision: 2.1 www.CommFront.com Page 3 of 4
■ PIN ASSIGNMENT
RS-232 Side (DB-9 Female Conne tor):
Pin: 1 4 6 7 8 2 3 5
Signal: DCD DSR DTR CTS RTS TX RX GND
Fun tion: tied together tied together TX RX GND
Note: Some software requires handshake line
a knowledgements. To satisfy the requirements,
the CVT-485A-1's handshake lines (RS232
side) are tied together (DCD, DSR, and DTR
tied together, CTS and RTS tied together).
Therefore, you don't have to modify your
existing software.
RS-485 Side (Terminal Blo k):
Terminal Blo k: A B G 120
Fun tion: RS485+ RS485- GND Tie to turn ON the 120Ω end-of-
line terminator
■ CONNECTIONS
Revision: 2.1 www.CommFront.com Page 4 of 4
■ 12 -OHM END-OF-LINE TERMINATION
Turn on the 120Ω end-of-line terminator (default: OFF) on both ends of the RS-
485 bus when the data rate is over 19.2kbps or the RS-485/RS-422’s distan e
ex eeds 660ft (200m).
■ TROUBLESHOOTING
Perform a loopba k test by using CommFront’s 232Analyzer software: Conne t two
numbers of CVT-485A-1 to your PC’s COM ports and run two instan es of the
232Analyzer software, then send ommands from one COM port, you should
re eive an e ho of the ommands sent on the other COM port. By performing a
simple loopba k test like this, you an test both the transmitter and re eiver of the
onverter. This is very helpful when you are in doubt about the performan e of
your onverter.