Installation; Maintenance - AT&T Bell System 331 Manual

SECTION 51 0-81 0-1 00
indication from 21C indicator or to OFF
position for visual indication only.
2.07
Associated Apparatus.
• Handset Push-to-Talk Switch: Depress
button in center of handle to talk; release
to listen. Handset plugs into jack.
• 52L Head Telephone Set: Provides
hands free operation of the 331-type telephone
set. Headset plugs into jack.
3. INSTALLATION
3.01
Locate the telephone set in accordance with
the customer's wishes and any special
instructions that may appear on the service order.
3.02
Install two KS-6522 dry cells (order separately)
by releasing the wing catch in the rear of
the upper shelf and swinging the entire shelf out
to allow access to the battery holder.
3.03
Line connections may be made by means of
the line cord and Hubbell plug or by
connecting inside wire directly to the two binding
posts in the upper compartment.
Caution: If Hubbell plug equipped line
cord is used, customer should be
cautioned to observe the warning
printed on the plug. This plug can
be accidentally inserted into a standard
220 volt power receptacle.
3.04
The 521 head telephone set (ordered separately)
is equipped with a plug-ended cord having
a connecting block located near the set end. If
monitoring is desired, a separate receiver can be
plugged into this connecting block.
3.05
Position the 21C indicator so that it is readily
visible from all directions. Buzzer (B1AL
ringer in 331A or P1B ringer in 331B) can be
connected or disconnected by means of the toggle
switch in the upper compartment.
4. MAINTENANCE
4.01
Maintenance of the ringer, optional handset,
and head telephone set is outlined in sections
covering these components.
Page 4
4.02
Battery Holder ..
• With batteries removed, battery contact
springs shall be a minimum
1/
4-inch closer
to each other than when the batteries are
installed. Gauge by eye.
• Battery holder retaining springs shall have
sufficient tension to hold tube and batteries
firmly in place. Adjust as required.
4.03
Hand Generator.
• If hand generator sticks or turns hard, due
to lack of lubrication, apply a small amount
of KS-1477412 lubricant to the gears, cam
surfaces, and shaft bearings. After application
of the lubricant, turn generator, using its
crank, several times to work the lubricant
into the parts.
• If relubricating the generator does not result
in free operation, cause of sticking or hard
turning may be due to breakdown of insulation
in the generator, in which case replace the
set.
• If crank handle should stick to threaded
shaft of generator and not release properly
for removal, short the binding posts together
to place a load on the generator and then
turn crank backwards. This should release
crank. To prevent recurrence, put small
amount of lubricating oil on threaded portion
of shaft.
4.04
Line Cord:
If Hubbell plug equipped line
cord is defective or does not have the warning
label in place around plug, replace the line cord
or place a tag near the plug containing the following
warning.
Warning: Do not insert into electrical
power.
5. CONNECTIONS
5.01
Connections for the 331B and 331A telephone
sets are shown in Fig. 5, 6, and 7, respectively.
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