AT&T Bell System 2634 Series Service Manual

BEU SYSTEM PRACTICES
AT & TCo Standard
SECTION 502-612-409
Issue 6, October 1980
SERVICE
2634- AND 2635-TYPE TELEPHONE SETS
CONNECTIONS AND MAINTENANCE
1. GENERAL
1.01
This section contains information for 2634DA
(MD), 2634DAM (MD), 2634DAMS1 (18-button)
and 2635DA (MD), 2635DAM (MD), 2635DAMS1
(30-button) CALL DIRECTOR® telephone sets used
with station line concentrator (Fig. 1, 2, 3, and 4).
1.02
This section is reissued to:
• Show 2634DAM and 2635DAM telephone set
MD
• Show 3-type speakerphone MD
• Show 819041971 (P-90D197) guard assembly
MD
• Add information on 2634DAMS1 and 2635DAMS1
telephone sets
• Add information on D-181006 Kit of Parts.
1.03
•All four letter coded sets are furnished
from the factory in only the numerical code
(1), and all other coded sets are rated MD. Sets
may be equipped with different modular key
arrangements by ordering the appropriate 635-,
658-type key, or 76A lamp socket. Refer to Section
502-603-101 for recommended layout arrangement
of field-installed keys.
1.04
The 2634DAMS1 and 2635DAMS1 sets are
furnished equipped with a new line switch
which breaks both the tip and ring side of the line
instead of the ring side only .•
2. CONNECTIONS
2.01
These sets are factory-wired for use with
1A1, 1A2, 6A, or •6B• key telephone system
(KTS). Refer to Division 518 for connections using
235- or 236-type key telephone units (KTU).
2.02
A 235-type KTU is associated with each
2634-type telephone set and a 236-type KTU
with each 2635-type telephone set. Because of
the single common talking and control lead pattern
in these sets, a line concentrator KTU must be
associated with each telephone set installed and
cannot be shared, even on a bridged station basis.
2.03
The 2634- and 2635-type sets that are
provided with D50AH (MD) or D80D (MD)
mounting cords require contact strip assemblies on
the 635-type keys. These sets are normally provided
with a 635A5C key (5-line pickup and hold) in the
first module. If desired, the 635A5C key can be
replaced with a 635AD5C key (4-line pickup, cutoff,
and hold). In this case the contact strip assemblies
for the 635AD5C key (840151039 and 840151047)
are furnished with the key.
Note: Contact strips are not required with
sets equipped with D50BD or D80E mounting
cord. A and A1 are common to all pickup
buttons through internal mounting cord wiring.
2.04
Because of the physical arrangement of the
635-type key, the contact strips do not extend
to the chaining switch. This requires additional
A1leads to each module (except the last), to extend
A lead control.
2.05
Mounting cords of these CALL DIRECTOR
sets terminate in individual plugs connected
to the rear of the keys. This permits rearrangement
of line appearances either in the set or at the key
equipment distribution point. Current production
sets are equipped with a satin-silver ( -87) mounting
cord.
NOTICE
Not for use or disclosure outside the
Bell System except under written agreement
Printed in U.S.A.
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