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& 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...
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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...
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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...
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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.
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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...
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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...
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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...
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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...
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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- -<>-...
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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...
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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.
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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...
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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.
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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.
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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;...
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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.
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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...
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"' 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 ••...
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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>...
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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...
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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.
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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 •...
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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...
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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...
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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...
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� ..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_...
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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,...
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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.
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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...
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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.
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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) •...
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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) •...
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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.
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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 �...
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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.
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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.
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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.
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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;...
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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.
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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)
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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.
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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.
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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...
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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:...
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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...
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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...
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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...
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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.
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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.
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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...
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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...
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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 - - -...
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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...
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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.
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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.
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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!?
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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...
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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.
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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.
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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 :...
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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 �...
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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.
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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 � �...
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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 "' "'...
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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...
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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 <>--<>...
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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�...
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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...
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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-"...
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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)
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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...
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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...
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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 •...
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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.
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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.
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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.
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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.
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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.
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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 .
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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.
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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±...
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"' J:,. J I B NOTE: -- -- REPRESENTS WIRING ON KSUs MANUFACTURED BEFORE MAY 1975. Fig. 67- Seventh Line Circuit...
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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) .
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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 .
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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.
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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.
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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( )
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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.
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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.
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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.
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"' 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.
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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).
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"' ..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 ) .
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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.
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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.
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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 -...
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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 -...
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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±...
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"' ..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·...
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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)
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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)
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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.
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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.
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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...
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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.
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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.
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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...
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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...
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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...
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SECTION 5 1 8-450-1 00 47 E C . -24V BATTERY Fig. 73-Power Distribution (Sheet 2 of 6) Page 1 26...
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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.
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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)
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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.
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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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