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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.