AT&T System 75, Wiring Diagram

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CHAPTER 5. AUXILIARY EQUIPMENT INSTALLATION
Installing Customer-Provided Terminal Using ADUs
Requirements
The interface between the switch and the customer’s data terminals and
host computer is through PDMs. Refer to section on installing PDMs for
details (Figures 5-21 and 5-22).
For V2 or V3 systems only, the customer’s asynchronous data terminals
can be connected through a Z3A ADU to a TN726 data line circuit pack
(Figure 5-24). Normally, the ADU is powered from the connected data
terminal. The ADU can also be remotely or locally powered using a
2012D transformer equipped with a 248B adapter. ADUs connected to
receive-only printers always require external power. The need for
external power must be determined experimentally for ADUs connected
to other devices. For details on ADU installation, refer to the Z3A
Asynchronous Data Unit User’s Manual (555-401-701).
Installation
1. Determine ADU port assignment from Data Module Form:
EXAMPLE:
Carrier Slot Circuit
2. Connect the RS-232 plug on the ADU to the data terminal.
Port Number B 02 01
3. Connect a 4-pair line cord (modular plug on both ends) from the
information outlet to the ADU (Figure 5-24).
4. Install patch cord/jumper wires at cross-connect field.
5. Administer per AT&T System 75 and System 75 XE—Implementation
(555-200-651) and AT&T System 75 and System 75 XE—Administration
(555-200-500).
Installing SMDR Interface
The interface between the switch and SMDR is through a PDM, trunk
data module (TDM), or 212-type modem. For connections between the
switch and the PDM or TDM, refer to the section on installing PDMs
(Figures 5-21 and 5-22). Administer per AT&T System 75 and System 75
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