UT3EN.doc 2005-02-23
www.roger.pl
1
UT-
3
COMMUNICATION INTERFACE
I
NTRODUCTION
The UT-3 interface is used to convert signals between RS232 and RS422 standards. On RS232 side interface deliver
TXD/RXD lines, on RS422 side the TXA/TXB/RXA/RXB lines are available. Usually the UT-3 interface is used to extend a
communication distance between two devices which communicate via serial link, nevertheless, it may be also used in other
situations, e.g. where a conversion between RS232 and RS422 standards is needed. A 1200m communication distance with
a bit rate of up to 115 200 Baud can be achieved with link established by two UT-3 interfaces. Several electrical diagrams
reflecting typical applications of the interface are attached to this guide.
I
NTERFACE
I
NSTALLATION
The interface should be installed in an enclosed room far from sources of moisture and heat. The interface is supplied with
12V DC rated voltage, it consumes up to 150 mA current. The electrical connection on the side of RS422 interface should be
made using a twisted-pair computer cable and the maximum length of the connection may not exceed 1200 m. The
maximum RS232 cable is limited to 15m (originally UT-3 is delivered with 1.5m RS232 cable with connector).
Note: Unshielded cables are recommended for RS42 (UTP), shielded cables are allowed only if strong electrical disturbances
exists.
If two UT-3 interfaces are interconnected, potential of power supply minuses of both interfaces must not differ more than –7.0
to +12.0 V DC. This requirement may be met in two ways: to earth the power supply minus of each of the installed interfaces
or to make an electrical connection between power supply minuses of each of the interfaces using an additional cable
equalizing their potentials. Several examples of UT-3 interface connections are illustrated on the electrical diagrams attached
to this document.
L
ED
I
NDICATION
The UT-3 interface is equipped with three LED indicators, which signalize the current status of the serial port line and the
presence of power supply voltage. The meaning of each indicator is described in the table below.
Name of LED indicator Indicator function
POWER Power supply.
TXD Data transmitted.
RXD Data received.
Ordering information
UT-3
UT-3 interface in a plastic enclosure equipped with a ready-made connection cable to
RS232 serial connector with DB9 plug.
UT-3-MD
UT-3 interface electronic module.
Technical specification
Power supply voltage 10...15 V DC
Input current: Avg. 80 mA (max. up to 150 mA)
Range of ambient temperature 0...+55º C.
Maximum transmission range on RS232 side 15 m (50 ft)
Maximum transmission range on RS422 side 1200 m (4000 ft)
Relative humidity 10 to 95% (no condensation)
Ingress Protection IP30 (indoor use only)
Dimensions 100 x 68 x 35 (mm)
Weight 80 g
Designation of connecting terminals
Name of terminal Function
GND Negative power supply terminal
+12V Positive power supply terminal
EARTH Connection to earth potential (grounding)
TXA RS422, transmitter line A,
TXB RS422, transmitter line B,
SHLD RS422 interface cable shield
TXD RS232 interface, transmitter line
GND Signal ground on RS232 side
RXD RS232 interface, receiver line
SHLD RS232 cable shield
RXA RS422, receiver line A
RXB RS422, receiver line B
RXD
GND
TXD 2
3
5
RXD
GND
TXD2
3
5
RXD
GND
TXD2
3
5
max. 1200 m
TXB
TXA
RXB
RXA
RXB
RXA
TXB
TXA
UT-2
RACS
PC computer
RACS
RXD
GND
TXD 2
3
5
RXD
GND
TXD2
3
5
CPR32
RXD
GND
TXD2
3
5
RXD
GND
TXD2
3
5
Comm.
Interface
UT-2
Comm.
Interface
UT-2
RXD
GND
TXD 2
3
5
RACS
PC computer
RACS
max. 1200 m
TXB
TXA
RXB
RXA
RXB
RXA
TXB
TXA
Connection of remote access controller(s) to RACS system trough UT-3 link.
Connection of remote RACS network to access system trough UT-3 link.
RACS communication bus (max. 1200m)
RACS communication bus
max. 1200m
RACS remote network
Connection of remote access
controller(s) to RACS system
COM
COM
Note: A total number of controllers connected in
local and remote location must not exceed 32.
.......
Cdr106EN
PR series
Access
Controller
PR series
Access
Controller
PR series
Access
Controller
PR series
Access
Controller
PR series
Access
Controller
PR series
Access
Controller
PR series
Access
Controller
Comm.
Interface
UT-3
Comm.
Interface
UT-2
Comm.
Interface
UT-3
Comm.
Interface
UT-3
Comm.
Interface
UT-3
A
B
A
A
B
B
One or more
access controllers
max. 15m max. 15m
max. 15m
max. 15m
max. 15m
max. 15m
cdr107EN
EARTH
EARTH
EARTH
EARTH
EARTH
EARTH
+12V
+12V
+12V
+12V
+12V
+12V
GND
GND
GND
GND
GND
GND
TXA
TXA
TXA
TXA
TXA
TXA
TXB
TXB
TXB
TXB
TXB
TXB
SHLD
SHLD
SHLD
SHLD
SHLD
SHLD
TXD
TXD
TXD
TXD
TXD
TXD
GND
GND
GND
GND
GND
GND
RXD
RXD
RXD
RXD
RXD
RXD
SHLD
SHLD
SHLD
SHLD
SHLD
SHLD
RXA
RXA
RXA
RXA
RXA
RXA
RXB
RXB
RXB
RXB
RXB
RXB
+12V
+12V
+12V
+12V
+12V
GND
GND
GND
GND
GND
UT-3
Power supply of UT-3 link with two separate grounding arrangements
Power supply of UT-3 link with one ground connection and additional wire between EARTH terminals
Power supply of UT-3 link from one supply source
Note:
When UT-3 is powered from one supply source
installer must consider a supply wires gauge in
order to guarantee that in worst case (when max.
supply current is deliver to UT-3 app.150mA)
the maximum voltage dropout between UT-3 and
power supply must not exceed 1.0Vdc
UT-3
UT-3
UT-3
UT-3
UT-3
RXD
RXD
RXD
RXD
RXD
RXD
GND
GND
GND
GND
GND
GND
TXD
TXD
TXD
TXD
TXD
TXD
2
2
2
2
2
2
3
3
3
3
3
3
5
5
5
5
5
5
max. 1200 m
Power
Supply
Power
Supply
Power
Supply
EARTH
Power
Supply
Power
Supply
Note: Only one power supply
minus may be grounded
max. 1200 m
EARTH
EARTH
EARTH
max. 1200 m
/
