(2) Remove the power cable stub (fig.
the red and white leads of the pov
2) from storage cabinet No. 6. If
cable stub to the neutral bus b
and the black lead to the phase-1,
the power source is a 50- to 60-
phase-2, or phase-3 bus bar.
cycle per second (cps), 120-240 -
(4) Remove the cover from the power
volt, single-phase, three-wire dis -
cable stub connector. Connect the
tribution system, connect the red
power cable stub to one end of the
and white leads of the power cable
stub to tie neutral bus bar and the
AN/MSC-31 power cable.
(5) Remove the cover fro m the IN
black lead to one of the 120-volt
bus bars of the commercial source.
POWER 115V AC receptacle in the
power and signal entrance box (fig.
(3) If the power source is a 50- to 60-
8) and connect the other end of tie
cps, 120-208-volt, 3-phase, four-
wire distribution system, connect
Section Ill. SIGNAL CONNECTIONS
pling procedures. Do not force or twist
the connectors during installation. Never
Signal circuits may be terminated at the
drop or place an uncovered 26-pair con-
AN/MSC-31 by the use of a 26-pair cable
nector on the ground.
and field wire connections.
(1) Cover removal.
a. Switchboards Circuits. Line termi-
nations for the SB-22(*)/PT may be com-
(a) With each hand, grasp the knurled
pleted by connecting a 26-pair cable at the
collar on each end of the con-
power and signal entrance box (fig. 8) or
nector and turn the collars until
by connecting field wire at the binding
the open position is reached (A
b. Intershelter Communication Circuits.
(b) Disengage the cam on top of the
Line terminations for the local telephone
cover from the slot on the con-
nector collar. Lift and remove
(LS-147(*)/FI) circuits may be made to
the PHONE (1 through 4) and INTERCOM
(2) Coupling procedure.
(a) Position the two 26-pair con-
binding posts, respectively, and to pairs
22 through 25 and pair 26, respectively,
nectors so that the cams drop
into the slots of the knurled col-
of the 26-pair cable receptacle in the power
and signal entrance box.
lars and the male contacts are
aligned with the female contacts
(b) Carefully press the two con-
nectors together (D, fig. 24).
(c) Lock the two connectors by turn-
To couple connectors on 26-pair cables
ing the knurled collars until the
Cable Assemblies, Telephone CX-4566/U
closed position is reached (E,
(250 ft) and CX-4760/U (15 ft), use the
procedure in a below. The CX-4566/U
(d) Lock the two connector covers
must be supplied by the shelter at which
the AN/MSC-31 signal circuits terminate.
(3) Uncoupling procedure,
in the power and signal entrance box (fig.
(a) Unlock the 26-pair connectors by
8), use the procedures in b below.
turning the knurled collars until
the open position is reached (A,
a. Coupling 26-Pair Connector.
Caution: Handle the 26-pair connectors
(b) Carefully pull the connector
carefully during the coupling and uncou-