Bus termination, Bus termination -4 – Sensaphone SCADA 3000 Users manual User Manual
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SCADA 3000 User’s Manual
Each module must be configured with its own unique address using the BUS ADDRESS
jumpers. You may mix & match up to 15 modules to suit your application’s requirements. The
example below shows a Bus Address setting of 9.
Address
Jumper Code
1
A B B B
2
B A B B
3
A A B B
4
B B A B
5
A B A B
6
B A A B
7
A A A B
8
B B B A
9
A B B A
10
B A B A
11
A A B A
12
B B A A
13
A B A A
14
B A A A
15
A A A A
Figure 5: Setting the Bus Address
Bus Termination
Located on each module is a jumper labeled BUS TERM. This jumper is used to terminate
the 4-wire communications bus.
Figure 6: Bus Termination jumper
Termination is required at the extreme ends of the communications network to minimize sig-
nal reflections that would otherwise cause data communication errors. To activate the Bus
Termination, move the jumper to the IN position. Note that this should only be activated if
the module is at the very end of the network. All other modules in between should have the
termination set to the OUT position. As a result, only 1 module should ever have the termina-
tion activated. The diagram below illustrates proper termination of the communications bus.