Westermo MDW-45 - Manual (Page 11)

11 6617-2203
Fuctional description
The MDW-45 is an RS-422/485 to RS-232 converter. This device can be used in multid-
rop and point to point applications to connect devices like PCs, PLCs, drives and other
automation equipment.
In 2-wire half duplex applications (RS-485) the MDW-45 can automatically control the
state of the data bus based just on the data it receives. This allows the unit to be used
with equipment that has no handshaking signal. The maximum transmission rate possible
is 115.2 kbit/s.
RS-422/485 RS-232
3
4
T+
T−
TD LED TD LED
3
TD
CTS
LED
S2:4
F1
0V
+5V
1
2
R+
R−
RTS
CTS
RD
RD
LED
7
8
2
B
B
0V SG
S1:6
DSR
6
+5V
5
S2:2
S2:1
S2:3
Power
supply
Isolated power supply
0V
+5V
+5V
Bus termination
0V
B
B
+5V
Bus termination
0V
B
B
A
A
A
RTS LED
MCU