Installation
118
Aastra 470 as of R1.2
syd-0337/1.2 – R1.2 – 11.2011
Connection
Tab. 58
Connection of BRI-S terminal interfaces
S bus configuration
The S bus is a four-wire, serial ISDN bus based on the DSS1 protocol (ETSI standard).
It starts in each case at an BRI-S interface of the communication server. Four bus
configurations are possible, depending on the line length and the number of ter-
minals:
Tab. 59
S bus configurations depending on line length and the number of terminals.
Note
The maximum number of terminals per S bus depends on the power
requirements of the terminals (see
).
Fig. 50
S bus, short
Communication server
Cable cores
Connection socket
Socket
Pin
BRI-S sig-
nal
BRI-S sig-
nal
Pin
Socket
1
–
–
1
2
–
–
2
3
c
c
3
4
f
f
4
5
e
e
5
6
d
d
6
7
–
–
7
8
–
–
8
S bus
Short
Short, V-shaped Long
Point-to-point
Length (max.)
Server
↔
terminal
Terminal 1
↔
Terminal 4
150 m
–
2
×
150 m
–
500 m
20 m
1’000 m
–
Number of terminals (max.)
8
8
4
1
1.
2.
3.
max. 150 m
2 x 100
Ω
Communica-
tion server
8. Connection
point