Mitel Aastra 470 System Manual page 146

Installation
Fig. 57 Connection for FXS mode: Phone/fax
Ports 1.5 and 1.6 on the call manager card and in each case the first two ports of
FXS cards (X.1 and X.2) are designed for long lines. The no-load voltage at these
ports is 51 VDC. All the other ports have a no-load voltage of 30 VDC. The loop cur-
rent is limited to 25 mA on all ports.
Tab. 69 Cable requirements for FXS mode: Phone/fax
Core pairs  cores
Stranded
Wire diameter, core
FXS resistance
Line length 0.6 mm diameter
Screening
FXS mode: 2-wire door
In this mode 2-wire door intercoms with DTMF control functions can be connected.
The no-load voltage in this mode is 24 VDC. The loop current is limited to 25 mA.
Fig. 58 Connection for FXS mode: 2-wire door
146
a
b
FXS interface
Ports for long lines
1  2
only with lengths > 200 m
0.4 ... 0.8 mm
max. 2  625 
max. 10 km
not required
a
b
FXS interface
Normal ports
1  2
only with lengths > 200 m
0.4 ... 0.8 mm
max. 2  250 
max. 4 km
not required
Aastra 470 as of R3.2
syd-0337/1.6 – R3.2 – 09.2014