Aastra 470 System Manual page 154

Installation
FXS mode: Control input
If FXS interfaces are configured as control inputs, one or more of the switch groups
1...20 can be switched between position 1, 2 and 3. An external switch or a relay is
connected for this purpose. An LED can be connected to the circuit to indicate the
switch state. The no-load voltage is 24 VDC; the current is limited to 25mA.
The permissible switch and loop resistances are as follows:
• Active state (On): < 1 k
• Passive state (Off ): > 4 k
There are no special requirements for the cables.
Warning
Control inputs must have a floating connection.
Fig. 60 Connection for FXS mode: Control input
In the switch group configuration in AMS the ports are assigned to the control in-
puts of a switch group. To be able to control all 3 switch positions of a switch group,
you need 2 control inputs which switch the switch position of the switch group de-
pending on the status.
Tab. 70 Switch group control via the control inputs
FXS control input 1
Off
On
Random
Other conditions:
• The same control inputs can control one or more switch groups.
• The same switch group can only be switched by the 2 assigned control inputs.
• Control of the switch groups using the control inputs takes priority over control
using function codes.
154
a
25mA
24 VDC
b
FXS interface
FXS control input 2
Off
Off
On
Switch positions of the switch group
Position 1
Position 2
Position 3
syd-0337/1.5 – R3.0 – 05.2013
Aastra 470 ab R3.0