1.10 Conversation FeaturesFeature Guide 891.10.10 Calling Party Control (CPC) Signal DetectionDescriptionA CPC (Calling Party Control) signal is an on-hook indication (disconnect signal) sent from an outside (CO)line when the other party hangs up. To maintain efficient utilisation of outside (CO) lines, the PBX monitorseach line's status and when a CPC signal is detected on a line, the PBX disconnects the line and alerts theextension with a reorder tone.Conditions• CPC Signal Detection is programmable for incoming outside (CO) line calls ( CPC SignalDetection—Incoming [420]) and for outgoing outside (CO) line calls ( CPC Signal Detection—Outgoing [421]).• If a CPC signal is detected during a call between a caller using the DISA feature ( 1.15.6 DirectInward System Access (DISA)) and an extension or an outside party, the call will be disconnected.• It is possible to select whether the PBX detects the reverse signal from incoming outside (CO) line callsfor the duration ( CPC Signal Detection—Incoming [420]) specified through system programming (Incoming Reverse [153]).
