Type büS

büS networks with maximum

network expansion

37

13.2

Star topology with a junction box

If a passive junction box is used, all the cables are stub lines. With a baud rate of 500 kbit/s, a total stub line

length of 25 metres is permitted. The maximum length of each stub line is limited to 5 metres. If all the stub

lines have the same length, the position of the termination resistor is irrelevant.

Junction box

Device 1

Device 3

Device 4

Device 5

Device 2

5 m

5 m

5 m

5 m

0.5 m

5 m

TR

PS

TR

Termination resistor

Diagnostics

TR

PS

Power supply

Measurement

point

MP

MP

Fig. 42: Star topology with a junction box

13.3

Tree topology with a junction box

With a tree topology, a total cable length of 94 metres was measured with 23 devices in the network. The

stub line length varies between 1 and 10 metres.

Device 1

Device 3

Device 4

Device 5

Device 6

Device 2

10 m

5 m

10 m

5 m

0.5 m

10 m

5 m

TR

PS

Termination resistor

Diagnostics

TR

PS

Power supply

Measurement point

MP

MP

Device 7

Device 9

Device 8

1 m

TR

Device 10

Device 11

Device 12

Device 13

Device 14

1 m

1 m

1 m

1 m

1 m

1 m

1 m

Device 18

Device 19

Device 20

Device 21

Device 22

3 m

3 m

3 m

3 m

3 m

3 m

3 m

3 m

Device 15

Device 16

Device 17

MP

10 m

7 m

Fig. 43: Tree topology with a junction box