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AT&T Bell System 7A Manual
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AT&T Bell System 7A Manual

AT&T Bell System 7A Manual

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BELL SYSTEM PRACTICES
AT
TCo Standard
CONTENTS
1 .
GENERAL
2.
DESCRIPTION OF APPARATUS
570A KSU
CONSOLES
EXTERNALLY MOUNTED APPARATUS
KEY TELEPHONE UNITS
KITS OF PARTS
TELEPHONE SETS
3.
INSTALLATION
PLANNING
ORDERING GUIDE
INSTALLING
A.
570A KSU
B.
Satellite Wiring Plan
C.
Telephone Sets
4.
FEATURES (IDENTIFICATION, OPERATION,
CONNECTIONS, AND TESTING)
BASIC FEATURES
A.
Automatic Button Restoration
B.
Common Audible
*Trademark
C.
Multiline Conferencing
7 A COMMUNICATION SYSTEM
(COM KEY* 718)
PAGE
2
3
3
1 1
1 1
15
22
25
3 1
3 1
32
35
35
35
37
38
3 8
38
38
40
NOTICE
Not for use or disclosure outside the
Bell System except under written agreement
Printed in U.S.A.
CONTENTS
D.
Pickup, Hold, and Illumination
E.
Tone and Voice Signaling
F.
2-Path Intercom
OPTIONAL FEATURES
A.
CO Ringing
B.
External Signaling Circuit
C.
Intercom Preset Conference
D.
Music-On-Hold
E.
Ring Transfer
Paging and Background Music
F.
G.
Power Failure Ringer
H.
Power Failure Transfer
J.
I.
Privacy
Privacy Release
K.
Recall
L.
Speakerphone
3B Speakerphone
4A Speakerphone
M.
Station Busy Consoles
Station Busy Console ( 6A 1) With DSS
SECTION 5 1 8-450- 1 00
Issue 3, October 1 976
PAGE
4 1
4 1
4 1
43
43
43
44
48
49
5 1
55
5 5
56
58
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59
63
63
Page 1

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  • Page 1 & BELL SYSTEM PRACTICES SECTION 5 1 8-450- 1 00 TCo Standard Issue 3, October 1 976 7 A COMMUNICATION SYSTEM (COM KEY* 718) CONTENTS PAGE CONTENTS PAGE GENERAL Pickup, Hold, and Illumination DESCRIPTION OF APPARATUS Tone and Voice Signaling 570A KSU 2-Path Intercom CONSOLES...
  • Page 2 SECTION 5 1 8-450-1 00 CONTENTS CONTENTS PAGE PAGE Station Busy Console (6B 1 ) With MW BACKGROUND MUSIC MUSIC-ON-HOLD (45 1 A OR B KTU) Station Restriction POWER DISTRIBUTION TOUCH-TONE® Dialing GENERAL MAINTENANCE GENERAL This section contains identification, installation, 5 70A KSU 1 .0 1 connection, operation, and maintenance...
  • Page 3 ISS 3, SECTION 5 1 8-450- 1 00 Since this reissue covers a general revision, arrows background music), power failure transfer, ring ordinarily used to indicate changes have been transfer, music-on-hold (utilizing CP music source), omitted. intercom preset conference, station busy console with direct station selection (DSS), station busy This issue is based on: console with message waiting (MW), intercom-only...
  • Page 4 SECTION 5 1 8-450- 1 00 FUSE PANEL 19C-TYPE POWER UNIT Fig. 1 - 570A KSU (Cover Removed) This eliminates the need f or an external Has designation strip holder and tab assembly • sta tion connections are made on serving as a retainer to lock KTUs in the the sta tion connection f ield blocks connectors.
  • Page 5 ISS 3, SECTION 5 1 8-450- 1 00 TABLE A FUSE A R RANGEMENT -570A KSU FUSE PANEL (SEE FIG. FUSE FUSE AMP POTENTIAL FUNCTION DESIG (TYPE) First CO/PBX Line Lamps Second CO/PBX Line Lamps Third CO/PBX Line Lamps 1-1/3(70A) lOVac Fourth CO/PBX Line Lamps Fifth CO/PBX Line Lamps...
  • Page 6 SECTION 5 1 8-450-1 00 lines, the optional message waiting or DSS TABLE B consoles, and the 33A voice coupler. L I N E STATUS LAMPS-570A KSU (d) Connecting blocks 4 and 5 (Fig. 5) provide LAMP LAMP terminals for connecting station codes 4 FUNCTION D ES I G CODE...
  • Page 7 ISS 3, SECTION 5 1 8-450- 1 00 RING TRANSFER COLUMN CO RING ANO CONFERENCE COLUMN PRESET �2 f3) -r t � 0 0 0 0 NOTE: NU�BERS SHOWN IN PARENTHESIS ( ) 0 0 0 REPRESENT THE CO/PBX LINES AND THE NU�BERS SHOWN IN 0 0 0 0 BRACKETS...
  • Page 8 SECTION 5 1 8-450- 1 00 NOTES: I. DIODES SHOWN COMPRISE FACTORY WIRED POLARITY GUARD. 2. THE FOLLOWING TERMINALS ARE STRAPPED ON THE FACTORY SIDE OF THE CONNECTING BLOCK: 12A TO 12C 128 TO 120 12E TO 12G 12F TO 12H 16A TO 16C 168 TO 160 16E TO 16G...
  • Page 9 ISS 3, SECTION 5 1 8-450- 1 00 INTERCOM o--o DSS CONSOLE TERMINALS STATION CODES o--o o--o MESSAGE WA I T NG CONSOLE TE R o---<>- -o- -<>- - 10 II <>-<>--<>- -<>- - I 12 13 16 17 18 o--o o---<>- -o- -<>-­...
  • Page 10 SECTION 5 1 8-450- 1 00 SEE TABlE A SEE TABlE B �@l��[Q]� ���[Q][Q]�� ���[Q][Q]� ������� POWER FA I LURE TRANS CKT PlilER UNIT 19Cl &85i] s1 ± IOVAC 0 !SIC ± IOV AC 0 400G LINE - 24V �,--- -,- --,-,-, 21 !TAL! - 24VDC 0 CO/PBX L INE CIRCU IT...
  • Page 11 ISS 3, SECTION 5 1 8-450- 1 00 Up to three selector consoles in any CONSOLES Note: combination can be used in a 7A Communication System. 6A 1 Selector Console (Station Busy Console With DSS) *Refer to Table C for color suffix. The 6A1 selector console (Fig.
  • Page 12 SECTION 5 1 8-450- 1 00 TABLE C COLOR ORDER ING G U I D E SPEAKERPHONE, 832-, 2832-TYPE TELEPHONE SETS FACEPLATES LOUDSPEAKER, AND 6At, 681 SELECTOR CONSOLES TRANSMITTER COLOR SUFFIX COLOR SUFFIX SUFFIX COLOR -100 Avocado Black -- {)3 - 1 0 8 Teak (Woodgrain ) Green...
  • Page 13 ISS 3, SECTION 5 1 8-450- 1 00 647AF5 KEYS * FACEPLATE KEYS OLDER CONSOLES EQUIPPED WITH 647C5 Fig. 8-68 1 Selector Console (MW) Ring transfer. • K8 Loudspeaker The K 8 loudspeaker (Fig. 10) i s a n indoor 2.
  • Page 14 SECTION 5 1 8-450-1 00 WOOD CASE 3/41N. TERMINAL STRIP FRONT VIEW REAR VIEW QUAD INSIDE WIRE TO KEY SERVICE UNIT MOUNTED OVER OUTLET BOX) � (LOUDSPEAKER MAY BE SINGLE MOUNTING C L I P WALL OR MOUNTING SURFACE VIEW A-A Fig.
  • Page 15 ISS 3, SECTION 5 1 8-450- 1 00 and new installations. In the 7 A System, the 424B/424C KTUs provide the following: Rotary dial selection • 1/2 IN. Nineteen dial codes (nine single-digit and • I/2 1N. ten 2-digit codes). In the 7A System, the first digit of Note: the 2-digi t code is 1;...
  • Page 16 SECTION 5 1 8-450-1 00 400G OPTIO CO OR PBX FEATURES T(CO) SHORT TIME DELAY TIMEOUT APPRO SECONDS) VISUAL LAMP W HOLD CKT R(CO) KEY TEL SET A U DIBLE s� I NT E R R UPTED R I N G S I G N AL HOOK NET.
  • Page 17 ISS 3, SECTION 5 1 8-450- 1 00 5�8 CONNEC 1 7 5 FACTORY OPTION 82-83 O P T I ON P LUG PROVIDED A1- A2 TE RMINALS TO P VIE W O F TH E O PT I ON 8LOCK� ANOLE ASSEM8 L C2- C3 T HE O P T I ON S Y MB O L S THAT ARE SH O W N CONNECTED * O P T I ON P LUG STORA G E P OS I T I ON (FOR USE l>i EN...
  • Page 18 "' 424C CONN CONN ffl6 • 2 4 � 4608 TRANSISTOR 4 ---7 TIUNSISTOit • TO NWER •24 6 ORO SUPft.Y •I TIU.NSISTOR 4568 KTU TO STATION 7 R I B VSI7 TO STATION 17 VSIO TO STATION 10 Y$11 •24 ••...
  • Page 19 440A KTU H IGH GROUP L I MITER TRANS ISTOR CKT Ql8 TRANSISTOR AMPLIF IER Q I S, Ql6 460 A LOll GROUP L I MITER TRANS I STOR CKT Q R 2 4 R 4 4 4248/C R 45 V>...
  • Page 20 SECTION 5 1 8-450- 1 00 CONN BLK � CONN CONN CONN �A R(CO) �5 TO BA VOICE COUPLER R(STA) R(CO) 21 � �9 R(STA) �0 R(CO) R(STA) R(CO) R(STA) R(CO) 26 � �1 R(STA) R(CO) �7 � �4 �B �2 R(CO) Fig.
  • Page 21 ISS 3, SECTION 5 1 8-450- 1 00 452A KTU I ST CONN EXT I TO 1ST LINE CO/PBX LINE RINGER EXRI EXT2 TO 2ND CO/PBX LINE L1 NE RINGER EXRZ EXT3 CO/PBX LINE RINGER EXR3 EXT4 TO 4TH LINE CO/PBX LINE RINGER...
  • Page 22 SECTION 5 1 8-450- 1 00 CIRCUIT Q4 CONN T RANSIS TOR INTERRUPTER CIRCUIT Q3 - 24 � A GRD POWER • I A BAT -24� SUPPLY C2 CR3 m�·� CIRCUIT Q5 CIRCUIT Fig. 1 7 - Condensed Functional Schematic of 455A KTU (Tone-Ringing Signal Generator Circuit) used in conj unction with the 424B or C KTU.
  • Page 24 SECTION 5 1 8-450- 1 00 TABLE D 7A COMMUNICATION SYSTEM TE LEPHONE SET FEATU RES 10-BUTTON SETS 1 1-BUTTON SETS 1 3-BUTTON SETS 832B(MDI 832C(MD) 832BM 832CM 832DM 832EM 832A(A&M) FEATURE STATUS 2832B(MDI 2832C(MD) 2832A(A&MI 2832BM 2832CM 2832DM • 2832EM •...
  • Page 25 ISS 3, SECTION 5 1 8-450- 1 00 CR I - 24 P/0 457C KTU I• f---j TO 424B/424C I• R I O CKTS Ql Q2 TO CONN BLOCK R I I 3 (TO 33A VO I C E COUPLER ) TRANS I STOR CKTS Q3 Q4 TO 4568 KTU...
  • Page 26 SECTION 5 1 8-450- 1 00 , - - - - - - - - - - - - - - - - - � 4608 TRANSISTOR �:RC UIT L B I -24V L B I S C I TRANS I STOR CIRCU I T Q2, Q 3 CR22...
  • Page 27 ISS 3 , SECTION 5 1 8-450- 1 00 P /0 CONN ro "" "" f- -- -- -"Nv- --7 C R I 7 C R I 4 TRANS I sTOR CRI5 C I RCU I T TRANS I STOR C I RCU I T I l l CR I B...
  • Page 28 � ..4788 KTU CHANNEL I L TERS (STAR) AND DETECTORS CONN H I GH BEF (STAR) CONN AND L().J LIMITER � I NPUT TRANSLAT I ON MEMORY AND 424C RELAY I VERS ENABLE L().J 8EF �STAR) A BAT AND H I GH L I M I TER A GRD - rL_...
  • Page 29 ISS 3, SECTION 5 1 8-450- 1 00 under the HOLD button is provided for use as a 832C/2832C (MD) Telephone Sets message waiting indicator. The 832C telephone set is a rotary dial 2.41 13-button key telephone set. The set has a Caution: The system may be disabled if lower row of ten buttons for 7 CO/PBX line pickups,...
  • Page 30 SECTION 5 1 8-450- 1 00 C O / P B X - 5 0 I NTE R C O M 1 5 A H A N D S ET H A ND S E T C O R D Fig.
  • Page 31 5 1 8 - 450- 1 00 SECTION 6 4 7 5 5 K E Y 23-2832CM-50 Fig. Telephone Set Has a wall providing adequate support and INSTALLATION • stability, or floor space away from foot PLANNING traffic and protected from vehicular traffic 3.01 Survey the area to be served by the 7A Has sufficient clearance above floor level to...
  • Page 32 SECTION 5 1 8-450- 1 00 is to be provided. T he results of the survey may indica te: Additional speakers located closer together • will be required. An auxiliary paging system (telephone • company or customer provided) will be required.
  • Page 33 ISS 3, SECTION 5 1 8-450- 1 00 Kit of Parts, D-180656 (Shelf Assembly) In tercom -Only Sets: • (order one for each 832/2832A, B, C, BM, Set, Telephone, 575AM (rotary dial) or CM type telephone set to be wall-mounted) •...
  • Page 34 SECTION 5 1 8-450-1 00 gongs, etc, and an external power supply Unit, Power, 215C1 • must be ordered as required.) Unit, Power, 19C2 (on earlier models of • U n it, Telephone Key, 4 4 0 A or 4 7 8 B KSU) •...
  • Page 35 ISS 3, SECTION 5 1 8-450- 1 00 Plate, Face, 6A2- * station code 3 is terminated on column H of • connecting block 3, and station codes 4 through 19 are terminated on columns A through H on *Refer to Table for color suffix.
  • Page 36 SECTION 5 1 8-450-1 00 CODES I NTERCOM STA T I ON A25B CONN CABLE 12 13 14 IS 1 6 18 1 9 COLOR LEAD DES � � 11-BL) � � 1 � 1 I � I BL-11 � o--<>- -o-o- -o- - 11-0 �...
  • Page 37 ISS 3, SECTION 5 1 8-450- 1 00 The limiting factors of a satellite-type wiring the satellite. The number of additional cable 3.08 plan are keeping the voltage drop in the conductors for lamp leads is calculated as follows: lamp loop to less than 2 volts and maintaining a low resistance A lead.
  • Page 38 SECTION 5 1 8-450- 1 00 and 2575AM telephone sets, refer to Section all depressed buttons return to the unoperated 503-603-120. position. This prevents inadvertent intrusion on calls in progress and insures that multiple buttons will not be left depressed on a set causing an T he telephone which is to be used as undesired conference from the idle set.
  • Page 39 ISS 3, SECTION 5 1 8-450- 1 00 Fig. 27-lnstallation of 832DM-50 Wall Telephone Set To move the common audible signal to a 4.08 station or stations other than, or in addition to, the attendant station (code 0), make the following changes on connecting block 1: (1) Remove the factory-provided strap between terminals F9 and Cl.
  • Page 40 SECTION 5 1 8-450-1 00 CO/PBX RING COLUMN tllf NOTES: I . NUMBERS SHOWN IN PARENTHESIS ( I ) ( ) REPRESENT THE DIODE 0 0 0 ASSOCIATED WITH EACH OF THE 7 CO/PBX LINES . TO REMOVE A PART I CULAR L I NE FROM THE COMMON AUDI BLE GROUP;...
  • Page 41 SECTION 5 1 8-450- 1 00 To make a call during a conference: a single tone followed by voice signaling. Voice 4. 1 3 signaling is used in conjunction with tone signaling (1) Depress HOLD button - all buttons restore. when calling a station on the intercom.
  • Page 42 SECTION 5 1 8-450- 1 00 02DP-87 PLUG (NOTE 2 ) LEAD 57 5AM OR 2 57 5AM TEL SET M"ffi CORD A25B GNAT (NOTE CONN CABLE P/0 CONN LAMP SOCKETS TERMI NAL BLK( ) 6l6A KEY S TR I P (BK-S) I T1 (BK-S)
  • Page 43 ISS 3, SECTION 5 1 8-450- 1 00 Intercom is factory-wired, requiring the 424C will ring at station 3 and the second CO/PBX will 4.24 (Fig. 13), 456B (Fig. 18), and 460B (Fig. 20) ring at station 16. KTUs furnished with the 570A KSU. See Fig. 31 for KTU locations in the KSU.
  • Page 44 SECTION 5 1 8-450- 1 00 * NUMBERS CO/PBX R I NG COLUMN SHOWN IN PARENTHESIS ( ) REPRESENT THE 7 INCOMING CO/PBX LINES . NUMBERS ARE FOR REFERENCE ONLY AND DO NOT APPEAR ON THE BLOCK. CONNECTIONS AS SHOWN CAUSE STATION 3 TO RING ON LINE I AND STATION 16 TO RING ON LINE 2.
  • Page 45 ISS 3, SECTION 5 1 8-450- 1 00 CONTROL � L - - � 22A-49 APPARATUS I NSIDE WIRE MAXIMUM RESISTANCE U N I T FOR EACH LEAD IS 25 OHMS P/0 CONN B L K 3 o--<l STAT I O N o--<l CODES o--<l...
  • Page 46 SECTION 5 1 8-450- 1 00 KSI6301- C ONTROL TYPE S I G N A L I N G DEVICE EXTERNAL INSIDE \liRE POWE R MAXIMUM RES STANCE SUPPLY APPARATUS EACH LEAD I S 2S OHMS, � UNIT _ _ _ 22A-49 CONNECTING BLOCK NOTE:...
  • Page 47 ISS 3, SECTION 5 1 8-450- 1 00 TO OUTLET IN LIST 15, 16, R ELAY fO R DUAL, POTENTIAL USE, O R TO TO PWER TO POII E R PWE R R ECEPTACLE IN R ECEPTACLE R ECEPTACLE BACKBOX FO R SINGLE IN BACK BOX I N BACKBOX POTENTIAL USE...
  • Page 48 SECTION 5 1 8-450-1 00 takes precedence over CO/PBX ringing at a preset fuses in voice co upler. conference station. custom er w a n ts copy of the Technical Reference covering To connect preset conference, strap the 4.34 voice coupler, con tact terminals in the preset conference row to...
  • Page 49 ISS 3, SECTION 5 1 8-450- 1 00 PRESET CONFERENCE COLUMN PRESE CONFERENCE SHOW CONNECT IONS STAT I ONS t REMOVE FACTORY WIRED FOR PROV OED STRAP STAT I O CODES PRESET ON FERENCE TERMI NALS /0 COHN Fig. 36-Connections for Intercom Preset Conference The flexible station ring transfer arrangement Ring Transfer utilizes a 6041G key to permit any one of up to...
  • Page 50 SECTION 5 1 8-450- 1 00 5TOA ISU 0 0 0 0 0 To transfer ringing back to the attendant station, depress the RING TR button again (which releases it). Afterward, operate the release button on the B B B 6041G key.
  • Page 51 ISS 3, SECTION S 1 8-4SO- 1 00 TELEPHONE SET C O NNECTIONS fO R T R ANSfE R . - D-180487 KIT O f PARTS REQUI R ED fOR 832A AND 2832A TEL SETS. - CONNECTI ONS ONLY fOR 832C AND Rl NG 2832C TEL SETS.
  • Page 52 SECTION 5 1 8-450-1 00 ATTENDANT TEL SET C O DE 0 (co) � � C F � · :� R I N G T R BUTTON (NT) 6041G-KEY COMMON I I I I l l C O DE 3 TEL SET 44 H TEL SET CODE...
  • Page 53 ISS 3, SECTION 5 1 8-450- 1 00 Make connections as follows: 981-251-100 for general information on loudspeaker paging system. (1) Install 457C KTU in J15. See Fig. 42 for KTU location. Cau tion: A void placing loudspeakers dir�ctly in f ront of or close to sta tions (2) If background music is provided, install the tha t will u tilize...
  • Page 56 SECTION 5 1 8-450- 1 00 P /0 CONN BLK I INSTALLER PROVIDED STRAP - - - · I A-49 PARATUS - - - - - - - - - LOOP RES I STANCE ;�� ��� �� � � ���� - - - - - .., TO TELCO - - -...
  • Page 57 ISS 3, SECTION 5 1 8-450- 1 00 POWER rA I LURE TRANSrER COLU�S NUMBERS SHOWN IN PARENTHES I S REPRESENT T I NCOMING CO/PBX L I NE NUMBERS ARE rOR RErERENCE ONLY AND DO NOT APPEAR ON THE BLOC K . CONNECT I ONS A S SHOWN PUTS POWER rA I LURE I N THE STATION CABLE rOR STAT ION...
  • Page 58 SECTION 5 1 8-450- 1 00 570A 0 0 0 0 0 0 0 (d) Test all sets equipped with a privacy circuit. B B B � To change a privacy station to a nonprivacy 4.63 station, disable the privacy circuit according to Table F or G.
  • Page 60 SECTION 5 1 8-450-1 00 To answer an incoming call using speakerphone: With transmitter disabled, conversation Note: 4.78 will not be transmitted to the distant station; ( 1 ) When audible tone signals an incoming call, however, the distant party may be heard over the loudspeaker.
  • Page 61 ISS 3, SECTION 5 1 8-450- 1 00 TABLE F 832/2832A, B, BM, AND DM TE LEPHONE SET CONNECTIONS TO R EMOVE P R IVACY C I R C U I T MOVE LEAD DISCONN ECT L EAD FROM COLOR FROM T E L SET PR IVACY BOAR!?
  • Page 62 SECTION 5 1 8-450-1 00 TABLE H 832A AN D 2832A TE LEPHONE SET CONNECTIONS FOR PRI VACY R E LEASE BUTTON (D-1 80488 KIT OF PARTS) PRIVACY PR IVACY MOVE LEADS CONNECT TO MOVE LEADS TEL SET BOARD R E LEASE FROM TEL SET T E L SET TO PR IVACY...
  • Page 63 Station Busy Console ( 6A 1 ) With DSS ISS 3, SECTION 5 1 8-450- 1 00 TABLE By depressing the appropriate button on ALL 832/2832-TYPE TE LEPHONE 4.84 the 6Al console, an attendant may signal SET CONNECTIONS TO DISABLE any station over the intercom or make announcements PRIVACY R E LEASE BUTTON over the paging system.
  • Page 64 SECTION 5 1 8-450-l 00 TABLE l 38 SPE A K E R PHONE CONN ECTIONS CONNECT LEADS FROM CORD COLORS CONNECT LEADS TO 558 LEAD CONTROL UNIT TEL SET TRMTR SPEAKER TRNSF DESIG DIDR R2FK TERM. TERM. TERM. TERM. TERM.
  • Page 65 ISS 3, SECTION 5 1 8-450- 1 00 TABLE M 4A SPE A K E R PHONE CONN E CTIONS M 1 6C CORD T E LEPHONE SET TERMINAL LEAD COLOR LEAD DESIG 832-TVPE 2832-TVPE W-BR BL-W W-BL RR (Network) To reduce the volume of voice signaling or ringing while Note: on speakerphone, make the following changes :...
  • Page 66 SECTION S 1 8-450- 1 00 f11111J 111111� I1111U f11111R I11111R 647J5C 6 5 4 3 2 1 L LG 6 5 4 3 2 1 LLG 6 5 4 3 2 1 L LG 6 5 4 3 2 1 L LG 6 5 4 3 2 1 LLG �...
  • Page 67 ISS 3, SECTION 5 1 8-450- 1 00 111111� r11111� 111111� 111111� 1u111� nun 6 5 4 3 2 1 L l. G 6 5 4 3 2 1 L LG 6 5 4 3 2 1 L LG 6 5 4 3 2 1 L LG 6 5 4 3 2 1 L L.
  • Page 68 SECTION 5 1 8-450- 1 00 11 � 11 � 11 � 11 � 11 � 647AF5 � 647C5 L LG L LG L LG L LG L LG KEY 2 "' => (W-BRI (R-01 (R-SI SPARE SPARE SPARE � �...
  • Page 69 ISS 3, SECTION 5 1 8-450- 1 00 11 � 11 � 11 � 11 � 11 � � L LG L LG L LG L LG > >-- (SKI (SR-VI (G-V) (0-YI (V-Ol (V-SI 11 � � � L LG L LG "' "'...
  • Page 71 A 2 5 B C O N N C A B L E A 2 5 B C O N N C A B L E ISS 3, SECTION 5 1 8-450- 1 00 C O L O R A D D E S G C O L O R L E A D D E S...
  • Page 72 SECTION S 1 8-450-1 00 A25B CONN CABLE A25B CONN CABLE LEAD LEAD COLOR DES I G P/0 CONN BLK J OES I G COLOR (W-BL) BL-W (W-- 0 ) o--o o--o o--<l 5 (G-W (G W) o--o (W-BR) (W-BR) o--o BR-W <>--<>...
  • Page 73 ISS 3, SECTION 5 1 8-450- 1 00 I NS I DE W I R I NG CABLE I N ROWS I THROU GH 39 AND 42 THROU GH 50, LEAD COLOR w� DES I G BL-W R-8L (W-8R) BR-W R�...
  • Page 74 SECTION 5 1 8-450-1 00 (Bl -11 ) INSIDE W I R I NG CABLE LEAD COLOR - - - DES I G -- - - - iWr "'"'OOw (W�L) TO FIRST A25B MW CONSOLE CONN CABLE w� G -Il COLORS SAME W�R...
  • Page 75 A25B CONN CABLE I N S I DE W I R I NG CABLE (W-BL) AND C IN ROWS 1 -39 AND 42-50. {BL�) LEAD COLOR (W-0) COLOR DfS I G (0�) (W-BL) o--o l """ BL-" o--o o--o "-BR o--o D-"...
  • Page 76 I - - - - - - - - - - l "' � ..A25B CONN CABLE D INSIDE W I R I NG CABLE LEAD LEAD F I RST COLOR OESIG COLOR DEStG o--o I (W-&) (BL-") o--o (Bl-") A25B (W-<J)
  • Page 77 ISS 3, SECT ION 5 1 8-450 - 1 00 D I NS I DE W I R ING CABLE I NSTALL B BR I DO I NG CL I PS ACROSS COLUMNS B AND C ROWS 1 -1 9, 26-�9, AND 42-?Q, LEAD COLOR DES I G...
  • Page 78 SECTION 5 1 8-450- 1 00 I NSTALL B BR I D G I NG C L I PS ACROSS D I NS I DE W I R I N G CABLE IN ROWS 1-19 AND 26-50. COLUMNS B AND LEAD COLOR DE5 1 G...
  • Page 80 SECTION 5 1 8-450- 1 00 Should the replacement KTU not clear the Maintenance information for the following 6.02 • trouble, the trouble is external and circuits is provided: original should be returned to CO/PBX line circuits-400-Type KTU • service. CO/PBX line ringing arrangements No field maintenance is to be performed on •...
  • Page 81 ISS 3, SECTION 5 1 8-450- 1 00 No attempt should be made to repair Calls can be transferred to one alternate Note: • or modify KTUs in the field. Replace defective station other than the attendant by adding KTUs with one known to be in working order. option on block 1.
  • Page 83 ISS 3, SECTION 5 1 8-450- 1 00 Tables AG, AH, AI, AJ, and Fig. 72 are 6.20 MUSIC-ON-HOLD-45 1 A OR B KTU provided as an aid in the maintenance of background music and music-on-hold circuits. The same music source used for background 6.
  • Page 84 TABLE 0 SECTION 5 1 8-450- 1 00 TROUBLE ANALYSIS TABLE POSSIBLE SOLUTION TROUBLE POSSI B L E CAUSE Check incoming tip and ring with test set. Incoming CO/PBX line is dead. Incoming tip and ring terminated on Check connections. the wrong terminals.
  • Page 85 TABLE 0 (Conti ISS 3, SECTION 5 1 8-450- 1 00 TROUBLE ANALYSIS TABLE POSSIBLE SOLUTION TROUBLE POSSIBLE CAUSE Y3 relay in selector (424B/424C KTU ) Check that CG O -CGl strap is removed. Incorrect See Fig. 50. intercom codes is not dropping.
  • Page 86 TABLE 0 (Coni) SECTION 5 1 8-450- 1 00 TROUBLE ANALYSIS TABLE POSSI B L E SOLUTION TROUBLE POSSI B L E CAUSE 457C KTU is not plugged in Check that KTU is properly seated and correctly. See Fig. 42. is in right connector.
  • Page 87 ISS 3, SECTION S 1 8-450- 1 00 TABLE P 400.TYPE KTU LINE CI RCUIT At station , depress associated line button and go off-hook. FAI LU R E Lamp lights-no dial tone Dial tone heard and associated Wrong line connections. line lamp lights steady .
  • Page 88 SECTION 5 1 8-450- 1 00 TABLE P (Cont) 400-TYPE KTU L I N E CI RCUIT With party on line, depress HOLD. F A I L U R E Line button restores-lamp Relay L, B and/or C not goes to wink (120 IPM ) . operated.
  • Page 89 ISS 3, SECTION 5 1 8-450- 1 00 TABLE R I NPUTS AND OUTPUTS-400-TYPE KTU TEST MON/TALK TEST FOR REMARKS FROM SWITCH INPUTS CO/PBX dial tone TALK B Ground B BAT MG - interrupter ground LW - 10V± at 120 IPM With interrupter running LF - 10V±...
  • Page 90 "' J l 8 CONNECTING BLOCKS KSU CONNECTOR T 1 (CO) -- - - ( 3 ) (CO) -- - - ( 0 ) - - - (4•1 1 ) - -, ( 3 ) Tl ( 12·18) (0 ) (4•...
  • Page 91 J I B l�:::: :: : :: - � n "' �::: : :;::: _ .., :::: :: ::.: :: "' � ..::::�::: :. NOTE: :::::.: (A-HI :: : :: :: : REPRESENTS WIRING ON KSUs MANUFACTURED BEFORE MAY 1975. .i:.
  • Page 92 ..� ..CONNECTOR "" ..NOTE: ---- REPRESENTS WIRING ON KSUs MANUFACTURED BEFORE MAY 197�. Fig. 63 - Third Line Circuit...
  • Page 93 CONNECT! NG BLOCKS KSU CONNECTOR �4A T 4 (CO) ( 3 ) R4 (CO) T4 (0 ) � ( 4 - 1 _1_2__ _ _ _ T4 ( 1 2-18) -- - - R4 ( 0) 1 6 H R4 (4- 1 1 ) _ _ _ R4 ( 1 2- 1 8 ) L4 ( 0)
  • Page 94 � ..J I S 1975. NOTE: -- - - REPRESENTS WIRING ON KSUs MANUFACTURED BEFORE MAY Fig. 65- Fifth Line Circuit...
  • Page 95 CONNECT I NG BLOCKS KSU CONNECTOR - - - � ;f_ _ _ _ T 6 (4- 1 1 ) 2 18 � �- � ( A -H ) �(OJ_ _ - - - �( 3 l_ __!§ k•.!.l. - - - �...
  • Page 96 "' J:,. J I B NOTE: -- -- REPRESENTS WIRING ON KSUs MANUFACTURED BEFORE MAY 1975. Fig. 67- Seventh Line Circuit...
  • Page 97 ISS 3, SECTION S 1 8-450- 1 00 TABLE S CO/PBX LINE R I N G I N G AR RANGEMENTS CO/PBX ringing on any line. FAILURE Tone ringing heard at attendant (a) No tone ringing at attendant­ station (0) and alternate station any lines (if option S is provided) .
  • Page 98 SECTION 5 1 8-450-1 00 TABLE T LEAD TABLE-CO/PBX LINE R I N G I N G AR RANGEME NTS LEAD FUNCTION DESIG Central Office ringing lead-tone ringing is applied to this lead from RO lead of 455A KTU, interrupter, CO( ) RN lead, 400-type KTU, RC( ) lead, common audible diodes, and cross-connect on block 1 .
  • Page 99 R C I :;�}' (NOTE 2 ) � f ::n �C4 :�:::t:: :::�==t =�:::·:· : = 0 > · ::;@ R I N G NOTES' "' I . PLACE STRAP FROM 24F TO D E S I RED TERM I NAL IN COLUMN C TRANSFER STATION (OPT IOM 2.
  • Page 100 SECTION 5 1 8-450-1 00 TABLE U POWER FAI LURE TRANSFER CI RCUIT - 452A KTU CO/PBX ringing on line under test. FAI LURE Calls received at attendant N o commercial power t o KSU. station or alternate location. No battery and/or ground to 452A KTU-B SIG fuse on 19C-type power unit.
  • Page 101 ISS 3, SECTION 5 1 8-450- 1 00 TABLE V LEAD T ABLE-452A KTU KTU/CONNECTOR LEAD PIN NO. FUNCTION DESIG. Tip of extension ringer circuit from station (V-S) ER( ) Ring of extension ringer circuit from station (S-V) EXT( ) Tip side of audible circuit from KTU 1, 16, 28, 37, 27, 35, 8 EXR( )
  • Page 102 .."' ..CONN BLOCK KSU CONNECTOR "' "' Tl (CO ) T5 (CO ) R5 (CO ) R l (CO) 1 9E EXT 5 !{:�:�:!: EXR 5 - - ..., . • • EXT I - - --±"!- --o .
  • Page 103 ISS 3, SECTION 5 1 8-450- 1 00 TABLE X INTE RCOM (IC) CA L L Lift handset and depress button associated with idle IC path (lamp dark) . FAILURE Button flashes at 60 IPM. (a) No lamp I T and/or IR o f selected IC dial tone heard.
  • Page 104 SECTION S 1 8-450- 1 00 TABLE X (Cont) INTE RCOM (IC) CALL No tone burst Open BY1 lead-424B/424C, 456B, 460B. Defective voice and tone- alerting circuit-456B. Open SS lead-456B, 424B/ 424C. Open VS lead-424B/424C. Defective tel set amplifier (called station). Lamp continues to flash Open BY 1 lead-424B/424C, 460B.
  • Page 105 ISS 3, SECTION 5 1 8-450- 1 00 TABLE X (Cont) INTE RCOM (IC) CALL 2-digit IC call. Selector seized (same as single digit). Digit 1 dialed. FAI LURE Dial tone removed. (a) Dial tone not removed Selector reset for 2nd Open LK lead-424B/424C, 440A or 478B, 460B, DSS digit.
  • Page 106 "' TABLE Y "' LEAD TABLE-I N T E R COM C I R C U I T "' LEAD KTU/CONN ECTOR FUNCTION DESIG PIN NUMBER Switched B battery - when 424B/424C KTU is seized, this lead applies -24V B to Jl0-35 460B KTU to start intercom dial tone.
  • Page 107 TABLE Y (Cont) LEAD TAB LE-INTERCOM CI RCUIT LEAD KTU/CONNECTOR FUNCTION DESIG PIN NUMBER J l 0-30 Dial tone disconnect - ground is applied to this lead by the selector after first digit of an Jl2-30 intercom code is dialed to stop dial tone. J14-26 Transfer digit 2 - provides ground from DSS console to operate TR, TRl relays (codes 10-19).
  • Page 108 "' ..TABLE Y (Coni) "' LEAD TABLE-INTERCOM CI RCUIT "' LEAD KTU/CONNECTOR FUNCTION DESIG PIN NUMBER To ground - provides ground to selector timer via the RS1 lead. J9-38 TOUCH-TONE ground - supplies ground to control adapter when selector is seized (N option) or J10-39 provides ground to DSS console selector relays (Q option ) .
  • Page 109 TABLE Y (Cont) LEAD TABLE-INTE RCOM CIRCUIT LEAD KTU/CONNECTOR FUNCTION DESIG PIN NUMBER VS18 Station ringing - voice signaling lead - code 18. J9-31 VS-19 Station ringing - voice signaling lead - code 19. J9-9 Selector counter relay No. 1 ground - provides ground t o operate Y 1 counting relay from J10-25 TOUCH-TONE adapter of DSS console.
  • Page 110 SECTION 5 1 8-450-1 00 TABLE Z I NPUTS AND OUTPUTS-424B/424C KTU TEST MON/TALK TEST FOR REMARKS FROM SWITCH I NPUTS Jl0-18 A Battery GROUND TALK Jl0-17 B Battery J18-17 J9-1 5 B Ground TALK J18-18 Jl0-3 A Ground OUTPUTS 1 sec.
  • Page 111 ISS 3, SECTION 5 1 8-450- 1 00 TABLE AA I N PUTS AND OUTPUTS-440A OR 478B KTU TEST MON/TALK TEST FOR REMARKS FROM SWITCH I NPUTS GROUND J14-8 TALK A Battery J13-3 Required for 478B A BAT. TALK A Ground J14-3 KTU only Either IC path seized -...
  • Page 112 ISS 3, SECTION S 1 8-4S0- 1 00 TABLE AA I NPUTS AND OUTPUTS-440A OR 4788 KTU TEST MON/TAL K TEST FOR REMARKS FROM SWITCH INPUTS GROUND J14-8 TALK A Battery J13-3 Required for 478B A BAT- TALK A Ground J1 4-3 KTU only Either IC path seized -...
  • Page 113 ISS 3, SECTION S 1 8-450- 1 00 TABLE AC INPUTS AND OUTPUTS - 4608 KTU TEST MON/TALK REMARKS TEST FOR FROM SWITCH INPUTS A BAT. - intercom talk Jl l-18 battery TALK B BAT. - intercom relay Jl l - 1 7 battery GROUND 10V±...
  • Page 114 "' ..CONNECT lNG BLOCK KSU CC<'<NECTOR J l l ITI (0) I T I (3 ) ITI (4• 1 1 ) I T I ( 1 2· 1 8 ) IR I (0 ) I R I (3 ) lR I (4·...
  • Page 115 C O NNECT! BL O CK KSU CONNECT O R JI O J l l J 12 J 14 J 16 IL2(0) ll2 (3) 35 B • ( A-Hl "' "' _ .., "' "' "'0 I.CI Fig. 70-lntercom Circuit (Sheet 2 of 4)
  • Page 116 V> ..· " � J 1 6 J 1 5 am� �: " " " -- �@ - - - -t!- - -m- ���=$3 ::::::::::-� 1 00 Fig. 70-lntercom Circuit (Sheet 3 of 4)
  • Page 117 KSU CONNECTOR J I S J 1 6 J 1 2 J l 4 Il l THOUT OSS PRESET CONFERENCE Ill THOUT PRESET !DNFERENCE "' "' ..� Fig. 70-lntercom Circuit (Sheet 4 of 4)
  • Page 118 SECTION S 1 8-450- 1 00 TABLE AD PAGING-457C KTU Lift handset and depress button associated with idle IC path (lamp dark) . FAILURE Refer to sequence on IC call. Associated button flashes and IC dial tone heard. Dial paging code (digit 2 ) . F A I L U R E Background music (if provided) Defective selector.
  • Page 119 ISS 3, SECTION 5 1 8-450- 1 00 TABLE AE LEAD TABLE - 457C KTU L E A D KSU/CONNECTOR FUNCTION DESIG. PIN NO. Paging input - voice and tone alerting J15-16 input from the 456B KTU. Paging code - when code 2 is dialed, -24V is applied to this lead from J15-19 456B KTU to enable amplifier.
  • Page 120 SECTION S 1 8-450- 1 00 KSU CONNECTO R BLOCK CONN J 1 4 J l 5 I IH TO SPEAKERS �il l H 1 @:f: : ::::=, .s; : :::�::: � : :f:f:3�: m� = �w: Fig. 7 1 - Paging Connections Page 1 20...
  • Page 121 ISS 3 , SECTION 5 1 8-450- 100 TABLE AG BACKGROUND MUSIC Paging circuit idle. 1 . COAM music source FAI L U R E Background music heard. defective, connected wrong, or volume set improperly. 2. Defective 33A coupler, fuses operated, or volume set improperly.
  • Page 122 SECTION S 1 8-450-1 00 TABLE AH MUSI C ON HOLD Call in progress on CO/PBX line. Hold button depressed at 7 A station. FAI L U R E Line button restores; lamp (a) Line circuit troubles­ flashes. Background music refer to sequence on heard by held party.
  • Page 123 ISS 3, SECTION S 1 8-450-100 TABLE AI LEAD TABLE - 451 A KTU LEAD FUNCTION KSU/CONNECTOR PIN NO. DESIG Music tip - tip side of music source input - J18-35 through 33A voice coupler Music ring - ring side of music source input - J18-36 through 33A voice coupler Ring (Central Office ) - multiple of ring side...
  • Page 124 SECTION 5 1 8-450-1 00 " COHNECT I NG BLOCK KSU CONNECTOR . , . R l (CO ) RZ(CO) R3(CO) - - - - �m = ::::::::�: m� PAG I NG BACKGROUND MUS I C Fig. 72 - Music-On-Hold A n d Background Music Page 1 24...
  • Page 125 ISS 3 , SECTION 5 1 8-450-1 00 1 9 C2/3 FUSE CONNECT I NG BLOCKS P<7WER UNIT PANEL CONNECTORS DC A TLK TLK GRD J I O 4 1 G 4 1 H 4 1 8 4 1 8 U WIRED FOR 440A K T U ) TLK GRD...
  • Page 126 SECTION 5 1 8-450-1 00 47 E C . -24V BATTERY Fig. 73-Power Distribution (Sheet 2 of 6) Page 1 26...
  • Page 127 ISS 3, SECTION 5 1 8-450-100 19C2/3 FUSE CONNECTING BL O CKS KSU CONNECTORS P(1JER PANEL UNI T SIG GRD � - - - - - - , J l 4 WIR lNG INSTALLED FORI USE OF 4788 L I � T � D � F __:� A - 3 7 8 GROUND Fig.
  • Page 128 SECTION 5 1 8-450-1 00 BLOCKS CONNECT I NG * BEFORE JULY 1 975, C 1 - 1 WAS CONNECTED TO R l -2 I NSTEAD OF F I Z-8 . I BV GRD E. -24C BATTERY ' " ] 25E 24E - - - (F2)
  • Page 129 ISS 3, SECTION 5 1 8-450- 1 00 1 9C2/3 FUSE CONNECT I NG BLOCKS POWER U N I T PANEL CONNECTORS I O V H. LAMP GROUND 3 1 8 3 1 G 3 1 H 3 1 8 I NTERCOM LAMPS M I SCELLANEOUS GROUNDS Fig.
  • Page 130 SECTION 5 1 8-450-1 00 19C2 / 3 CONNECT I NG BLOCKs J l 9 rusE ,,,,,,,, PWER SUPPLY PANEL CONNECT K. STAT I ON LAMP FUNCT I ONS J l l L . MOTOfl START LEAO Fig. 73- Power Distribution (Sheet 6 of 6) Page 1 30 1 30 Pages...

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