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Installation
128
Aastra 470 as of R1.2
syd-0337/1.2 – R1.2 – 11.2011
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
Ω
• Passive state (Off ): > 4 k
Ω
There are no special requirements for the cables.
Warning
Control inputs must have a floating connection.
Fig. 61
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. 68
Switch group control via the control inputs
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.
FXS control input 1
FXS control input 2
Switch positions of the switch group
Off
Off
Position 1
On
Off
Position 2
Random
On
Position 3
a
b
24 VDC
25mA
FXS interface