7.3.2
Bus interruption (switch 1)
Bus interruption DIP switch 4 can be set to define how the data transmission unit
should behave in the event of loss of visual contact (see Chapter 3.7.4, page 19).
Set DIP switch 4 on the connection circuit board (switch 1) in accordance with your
requirements (see Fig. 33).
Attention !
For operation with Suconet K and the RS485 MPI protocol, the bus
interruption switch must be deactivated (switch position 0).
If a Profibus system consisting of 2 or more nodes is located on the other side of
the data transmission unit, the bus interruption switch must also be deactivated.
DIP switch
4
Bus interruption
0
No output to the bus if visual
contact is lost : Tristate-
condition; behaves as in
the case of line interruption.
1
If visual contact is lost bus
occupation is simulated until
visual contact with the
data transmission units is
re-established.
The setting for simulated bus access is shown in
the example for the case of visual contact loss.
7.3.3
Termination (switch 2)
A terminating resistor must be connected at both ends of a bus segment line. If the
data transmission unit is the last node of a bus segment, the terminating resistor
must be activated.
Use switch 2 of the connection circuit board to set the terminating resistances on
DIP switches 1, 2 in accordance with your requirements (see Fig. 33).
Attention !
Termination must not take place within a bus segment!
Both switches must be either on 1 or on 0.
DIP switch
1, 2
Termination
00
Switch position terminated
11
Switch position not terminated
In the example, no termination is set.
Notice:
Should problems occur during commissioning or if the data transmission path can-
not be put into service, refer to Chapter 8, "Error Diagnosis".
Leuze electronic
DDLS 170
41
