Maintenance - Bell System Practices 853AM Identification, Installation, Connections, And Maintenance

4.03
For connections, refer to Fig. 6 and 7. For
the third intercom line (used in COM KEY
2152 communication system) connect as shown in
Note, Fig. 6 or 7.
4.04
For connecting the HF AI feature (COM
KEY 2152 communication system only) refer
to Table A.
Fig. 5-lnstalling 853A Faceplate
5. MAINTENANCE
5.01
Maintenance replacement should be limited
to the following:
• Complete telephone sets
• Replaceable components.
5.02
When dial replacement is necessary in the
853AM telephone set, use an 8RA dial. First
remove terminal board mounting screw as shown
in Fig. 4. Remove dial by loosening adapter
ISS 1, SECTION 503-603-130
mounting screws and springing dial brackets
sufficiently to release dial from locating pins.
Transfer adapter brackets from dial being replaced
to new dial.
5.03
When dial replacement is necessary in the
2853AM telephone set, use the 35Y3A dial.
First remove terminal board mounting screw as
shown in Fig. 4. Then rotate terminal board
upward to gain access to dial mountin screws.
5.04
Maintenance of the 35-type TOUCH-TONE
dial is not recommended and the dial should
be replaced. Adapter brackets are not involved
when replacing the TOUCH-TONE dial.
5.05
When necessary to remove housing, the
faceplate must first be removed by using a
KS-21107 type releaser (Fig. 5) or equivalent in
catch in botton of faceplate. Housing can then be
removed by loosening two captive screws under
faceplate area.
5.06
The current production 635-type keys have
been modified for easy lamp replacement
by merely removing the lamp cap and inserting a
553-type tool through the hole in the top of the
button.
• TABLE
A.
HFAI CONNECTIONS
REMOVE
CONNECT TO
APPARATUS
LEAD FROM
635A5
COLOR
NET.
KEY
NET.
TERM.
TERM.
TERM.
Wiring
BL-V
G L2
Harness
LG
W-BL (Lamp
GRDi
BL-W 1
683AE
W-0
4
TRMTR
0-W 3
G-W L2
W-G G
W-BR
A
BR-W
K
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