Intruduction – Westermo MD-45 User Manual
Page 17
17
6157-2003
1. Intruduction
The MD-45 is used to convert between RS-422/485 and RS-232/V.24 signals. This device
is often used in multidrop applications connected to a PC or PLC.
In 2-wire half duplex applications (RS-485) the direction of the bus can be controlled
by data which means that the converter turns the bus depending on the data sent on the
bus. This makes it possible to use the unit with equipment that has no handshaking sig-
nals. The maximum transmission rate possible is 115.2 kbit/s.
CHANNEL
3
PWR
RD
TD
DCD2
DCD3
DCD4
CHANNEL 2
POWER
LD-01 DC
CHANNEL
4
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
R+
R-
T+
T-
T+
T-
R+
R-
CHANNEL
3
PWR
RD
TD
DCD2
DCD3
DCD4
CHANNEL 2
POWER
LD-01 DC
CHANNEL
4
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
R+
R-
T+
T-
T+
T-
R+
R-
CHANNEL
3
PWR
RD
TD
DCD2
DCD3
DCD4
CHANNEL 2
POWER
LD-01 DC
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
R+
R-
T+
T-
T+
T-
R+
R-