Sensaphone SCADA 3000 Users manual - Manual (Page 266)

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SCADA 3000 User’s Manual
the entire length by connecting it to the building earth ground. For best results, use ferromag-
netic conduit near critical sources of electrical interference. You can use aluminum conduit in
non-critical areas.
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
signal 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 ter-
mination set to the OUT position. As a result, only 1 module (plus the main unit) should ever
have the termination activated. The diagram following illustrates proper termination of the
communications bus.
Figure 7: Correct bus termination