AT&T RELEASE 2 - Manual (Page 16)

INSERT THE MODULES The control unit comes with covers in place and with the following modules
already installed:
● Power supply module
● Memory module
● Line module (line board)
● Voice terminal module (station board)
You have already removed the front and top covers to mount the unit on the
wall. The power supply module is on the left inside the control unit. See
Figure 10. The memory module houses a battery that will preserve all
programming for at least four days in case of a power failure. The voice
terminal module (station board) has 10 jacks for 10 voice terminal connections,
and the line module (line board) has 4 jacks for outside line connections and
one jack for auxiliary use. Notice the protective safety latches at the bottom
of the line and voice terminal module slots.
FIGURE 10 The control unit modules.
If you did not order a second line or voice terminal module, go on to the next
procedure, "Connect the Control Unit to the AC Outlet." However, if you
have ordered the additional two modules, insert them now following the
instructions below.
CAUTION: Make sure the power cord is unplugged and the power
switch on the control unit is set to Off before you insert or remove
any modules. You risk damage to the system and the modules if the
power is on during this procedure.
12 Step 1: Installing the Control Unit