Proxitron Piros OKSG L S18.194 S10, Руководство пользователя

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If multiple pyrometers should work together in a RS-485 bus system, every single pyrometer has to have an
own address. The ex works address is 01 with 9600 Baud. Please note that the pyrometers have to be
addressed individually before the connection. Every pyrometer needs its own address. The use of address
00 is not allowed and so it is locked ex works. The RS-485 provides a bus communication with up to 32
users.
It is absolutely important that both wires D+ and D
– are not swapped in one segment. They have to be
identical for all connected pyrometers and the master. This is the most common installation error!
The housing of the pyrometer has a direct connection to PE. So the shield connector (green/yellow) serves
only for extension and must not be connected to PE. Otherwise a ground loop can arise that leads to
interferences in the communication or to the flowing of equalizing currents. The pyrometer can be damaged
in this way.
All stations in a segment should be ideally connected one after another in a linear bus. The bus has to be
accomplished as a twisted 2-
wire line with a load resistance of 120 Ω (1/4 W). The 2-wire line should be
shielded if the length is greater than 100 m. The shield has to be applied at the bus master and must not be
connected with the shield connectors of the pyrometers.
The single pyrometers can be connected via stub for short distances (
maximum length 3 m ).
U
S
B
D-
D+
GND
R
S
-4
8
5
Interface module
RS-485 <=> USB
3310A14020
D
+
D
-
D
-
D
+
Pyrometer
Adresse 01
D
+
D
-
D
-
D
+
Pyrometer
Adresse 02
D
+
D
-
D
-
D
+
Pyrometer
Adresse 32
120 Ohm
1/4 W
By looping through the bus connection is more fail-safe and optimal. Therefore the both wires of the
connector cable are used to build a go-and-return line. The 2-wire line of the bus has to be disconnect for
that and has to be connected to the connector cable. So a total bus length up to 1200 m is possible.
.
U
S
B
D-
D+
GND
R
S
-4
8
5
120 Ohm
1/4 W
Interface module
RS-485 <=> USB
3310A14020
D
+
D
-
D
-
D
+
Pyrometer
Adresse 01
D
+
D
-
D
-
D
+
Pyrometer
Adresse 02
D
+
D
-
D
-
D
+
Pyrometer
Adresse 32
A further possibility to avoid troubles at the bus is to connect all GND wires (red). This is recommended when
using 2-wire lines without shielding.
120 Ohm
1/4 W
D
+
D
-
D
-
D
+
Pyrometer
Adresse 02
D
+
D
-
D
-
D
+
Pyrometer
Adresse 32
USB
D-
D+
GND R
S
-4
8
5
Interface module
RS-485 <=> USB
3310A14020
D
+
D
-
G
N
D
D
+
Pyrometer
Adresse 01
D
-
G
N
D
G
N
D
Bus-Master
Bus-Master
Bus-Master