5.14
RS-485 interface for MODBUS
RS-485 interface for networking via MODBUS, on ECblue BASIC in connection with AM-MODBUS
auxiliary module. Connection to:
“
A (D+)
”
,
“
B (D-)
”
and
“
GND
”
.
11.03.2014
v_am_modbus_connect.vsd
ID1
GND
A
(D+)
B
(D-)
ID2
GND
A
(D+)
B
(D-)
B
(D-)
ID1
GND
A
(D+)
B
(D-)
ID2
GND
A
(D+)
MODBUS
(RS-485)
MODBUS
(RS-485)
A
d
d
re
s
s
in
g
A
d
d
re
s
s
in
g
MODBUS
(RS-485)
MODBUS
(RS-485)
A
d
d
re
s
s
in
g
A
d
d
re
s
s
in
g
The connections for MODBUS
“
A (D+)
”
,
“
B (D-)
”
are available double and are connected with each other internally.
Information
•
You must ensure correct connection; i.e.
“
A (D+)
”
must also be connected on the following devices
to
“
A (D+)
”
. The same applies to
“
A (D+)
”
.
•
In addition, a "GND" connection must be established, as dissimilar potential (
over 10 V
) will lead to
the destruction of the RS-485 interface (e.g. lightning).
•
Except the data link
“
A (D+)
”
,
“
B (D-)
”
and
“
GND
”
(for automatic addressing additional
“
ID1
”
-
“
ID2
”
see following chapter) no further cable cores of the data line may be used.
•
Pay attention to suf
fi
cient distance from powerlines and motor wires (min. 20 cm).
•
A maximum of 64 participants can be directly connected to one another, and a further 63
participants via a repeater. The precise number depends on the respective master.
Example for MODBUS connection
MODBUS
26.02.2007
v_modbus_verbindung.vsd
The data line must be conducted from one device to the
next. No other type of wiring is allowed!
Always use only two wires of one lead (twisted pair) for
the connection.
Recommended wire types
1. CAT5 / CAT7 cables
2. J-Y (St) 2x2x0.6 (telephone cable)
3. AWG22 (2x2 twisted pair)
Max allowed wire length 1000 m (CAT5/7 500 m).
Assembly instructions
ECblue BASIC-MODBUS, ECblue BASIC
Electrical installation
L-BAL-F079D-GB 2044 Index 002
Part.-No.
32/80