Bell System Practices AT&T Plant Series Identification, Installation, Connections, And Maintenance page 9

1SS 2,
SECTION 501-410-101
[
T
I
( w-s)
F
CONTROL UNIT
TO KEY
w 0
2
i5A (MD)
554 *
EQUIP
R
LI
55B
(s-w)
28 28 10
0
ra
RI
4
[ BR-WI
v w I
19 19 I
m
TI
5
(W-BR)
RR
0
n
w
5 5 II
0
n n AG
6
(w-o)
w
1
A
7
(W-G)
TO KEY
21 4
EQUIF? -
L
n
P3
8
(W-EL)
w
w w
w 30
13
0
0
a
P4
9
( BL-W)
BB
12 12 2
TO KEY
Al
0
n
n
EQUIP
Al
10
(G-W)
L2
.
P LK
3
(o-w)
36 36 36
'---+%-J t
TFI
0
n n
0
n
0
' J
To
2012B
27 27 27
TF2
TRNSF
\
( NOTES I ANO 2)
LEAO
44A
MTG CORD
TRMTR
OESIG
CONN
BLOCK
TI14 T 7A
666A 666B
(NOTE 4)
LK
3
(BK) (BK-0)
II
8
w w
4 4 7
I I
0
cl
Ml
n
( BR-BL) (S-BK)
2
w w w
0
14 14 16
0
M2
2
0
0.
(w)
[BK-S)
5 3
w
13 13
8
0
n
PI
4
( BL) (BL-R)
4 2
w w
w
2 2 17
0
FI
5
(Y) (G-Y)
10 7
c.
w
u u
3 3 IB
O
s
7
(R) (O-SK)
e 5
0 w u
w
29 29 19
0
m c.
Al
8
(G) (Y-o)
9
6
w
w
u
w
24 24 30
R2FK
P
MTG CORO
760A
34 34
LS PK
0
n n
(
NOTE 3 )
!1
SPI
n
9
n
(G)
0
33
33 2s
0
c. n
(
NOTE 3)
*
SP2
10
(R)
w
u
0
NOTES:
I OUE TO L(MER ~TAGE RATING 201iA TRNSF SHOULO NOT BE
USE, TO POWER 55-TYPE CONTROL UNIT,
2. 00 NOT
USE ANY GROUNOEOPOWER
SUPPLY, SUCH AS THE 18V AC
TAP ON THE 101-7ypE POWER SUPPLY, TO POWER 55-TYPE CONTROL
UNIT. USE OF GROUNDEO POWER SUPPLY WILL AFFSCT OPE RATION
OF UNIT.
3. I F REOUCED LOUDSPEAKER VOLUME IS OESIRED, CONNECT SE?. LEAO
TO TERMINAL 24(55A) OR 3JX55B)
4. INSULATE ANO STORE UNUSED LEADS OF TI I A CORO.
* 55A CONTROL UNIT MOOI FIEO BY WESTERN ELECTRIC COMPANY.
t D- 1614138 CONNECTOR.
Fig. 6—F-56659 and F-56660 Telephone Set, Speakerphone Connections
Page 9