Termination switch on secondary side
The SITRANS I300 can be used in two different ways:
● As an end point in a bus segment to supply and communicate with a single device. For
example a Siemens flow meter with Modbus output. In this case the termination switch has
to be switched ON.
● To communicate with multiple EIA-485 IS devices, connected to the secondary side. In this
case the devices farthest away have to be terminated.
Set the termination switch to the appropriate position for your application.
Setting the termination switch on secondary side
Switch position
Termination
2)) 21
Termination switch on secondary side
right
ON
left
OFF
6.3
Setting the data rate
To set the data rate, put the DIP switch to the appropriate position. Refer the table below for the
corresponding switch settings. The DIP switch is located on the secondary side (bottom) of the
SITRANS I300. In default the setting of the DIP switch is 19.2 kbps. Make sure the data rate
matches the data rate of the EIA-485 network (primary side).
2
1
2
1
;
;
N
7(50,1$7,21
21
2))
21 ;
N
N
N
N
N
N
N
N
0
; ;
; ; ;
; ;
;
L
; ;
; ;
;
;
; ;
;
;
; ; ;
;
,6
(,$,6
% $ % $
5
;
7
;
Figure 6-1
DIP switch
Commissioning
6.3 Setting the data rate
SITRANS I300 Isolating power supply with EIA-485 interface
Operating Instructions, 01/2019, A5E45099319-AA
29
