3Com NBX 100 Installation Manual page 201

5 Install the telephone support bracket in the wall mount position as shown
in Figure 65.
6 Connect the AC power cord to the back of the telephone.
7 Hang the telephone on the mounting screws.
Be sure that the telephone slides down about ½-inch after you slip it over
the heads of the mounting screws. If you cannot slide it down, remove
the telephone and back out the mounting screws slightly.
8 Make sure the telephone sits firmly against the wall.
If necessary, remove the telephone and tighten the mounting screws
slightly.
9 Use the telephone's AC power converter to connect the telephone to an
AC wall outlet.
Connecting Telephones to the LAN 201