AT&T 518-600-016 There are various types of jacks on the line and station, Function as follows

MODULE JACKS	There are various types of jacks on the line and station
	modules (Figure 2-3).Each type of jack has a specific
	function as follows:
	●	Analog station jacks. These jacks are for analog
		voice terminals, analog data devices, and accessories.
	●	Basic telephone jacks. These jacks are for basic
		telephones with Touch-Tone or rotary dial capability.
		Do not connect MERLIN II system analog voice
		terminals to basic telephone jacks.
	●	Digital station jacks. These jacks are for digital voice
		terminals, digital voice/data sets, MPDMs, MTDMs,
		etc.
	●	Outside line jacks. These jacks are for outside lines
		provided by the local telephone company. You can
		also connect an optional loudspeaker paging device
		and/or music source to any of these jacks.
	●	Power Failure Telephone (PFT) jacks. These jacks
		are for basic telephones only. In case of a power
		outage, basic telephones plugged into these jacks

become operational. They do so by bridging onto the lowest line of the group of four line jacks with which they are associated. Do not use MERLIN II system voice terminals as power failure telephones.

Tie line jacks. These jacks are for a transmission facility dedicated to interconnect two private switching systems.

2-14 Wiring the System