SIGNALLING SYSTEM AC14
General Description
SSAC14 is a 1VF system (2280 Hz) that is used for 'Out of Area' exchange lines or external extensions off PBXs.

Out of Area Exchange Lines
The system comprises of 2 parts:-
The AT 60930 which is installed at the local exchange.
The AT 60391 which is installed at the main exchange.

External Extension
The system comprises of 2 parts:-
The AT 60930 which is located at the extension end.
The AT 60391 which is located at the PBX end.

Note:
Although SSAC14 is generally 2 wire working it may be modified to provide 4 wire working. SSAC14 is a unidirectional device which will only permit dialling in one direction.

 

 
 
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Last revised: April 28, 2025

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