3.2.3. STAR TYPE CONNECTION FOR DEVICES WITH RS422 INTERFACE – CONFIGURATION
OF 2-PORT RS485-OUT
Using the ADA-4044H, configured for operating with 2-port, 4-wire RS485 (the microswitch RS-485 PORT in position 4W), it's possible
to:
- connect 2 devices with 4-wire RS422 interface to 2-wire and 4-wire RS485 bus,
- separate other segments of RS422 bus from main network – what increases the operational reliability,
- convert RS485 to RS422 interface and inversely.
During the connecting, pay attention to the proper implementation of the connection according to the following drawings
Fig 7. Star type connection of devices with RS422 interface to 2-wire RS485 bus. Conversion of 2-wire RS485 network to 4-
wire RS422 network, device separation from main 2-wire network, extending the main bus by a further segments of 1200m,
signal amplification.
10
ADA-4044H
R
S
48
5(
2W
)
co
n
n
ec
to
r
R
x+
R
x-
G
N
D
T
x+
/
A
T
x-
/
B
IN
co
n
n
ec
to
r
R
S
48
5(
4W
)
O
U
T
co
n
n
ec
to
r
R
S
48
5
(4
W
)
R
2+
/A
4
R
2-
/B
4
T
2+
/A
3
T
2-
/B
3
R
t
R
t
V
ss
+
V
ss
-
V
ss
-
V
ss
+
P
o
w
er
s
up
p
ly
R
1+
/A
2
R
1-
/B
2
T
1+
/A
1
T
1-
/B
1
R
t
R
t
A
D
A
-4
04
4
H
S
L
A
V
E
SLAVE
R
S
48
5(
2W
)
co
n
n
ec
to
r
-
-
G
N
D
A
B
R
t
M
A
S
T
E
R
MASTER
Ma
in
R
S48
5 (
2W
) b
us
-
-
G
N
D
A
B
R
t
RS422
connector
Tx+
Tx-
GND
Rx+
Rx-
Rt
Rt
S
L
A
V
E
R
S
4
22
RS
422
con
nec
to
r
Tx+
Tx-
GN
D
Rx+
Rx-
Rt
Rt
S
LA
V
E
R
S
4
22
S
e
g
m
en
ts
o
f
2
xR
S
42
2
b
u
s
Summary of Contents for ADA-4044H
Page 15: ...15 ADA 4044H...
