Manual / Guide · 1964
Technical Bulletin 500-407: Leich Type 40 and Type 80 PABX
Small Leich/AE PABX systems.
Manual / Guide · 1964
Small Leich/AE PABX systems.
LEICH TYPE 40 AND TYPE 80 P-A-B-X r""'r'..... ~::,·-..;:\ . .-.-~..--:-. ,,...~--::..~ ... ---... i~~; ' .~ ....- .- . ') . ~. > - -~-...:-"'- .. . .,_, .c,·. :.s .,_ ~' '· 'cirram Technical Bulletin 500-407 AUTOMATIC ELECTRIC GE NtR~L TELEPHONE & ELECTRONICS G'J&E 5 1 TCI Library | www.telephonecollectors.info Automatic El_ectric Company General Offices, Laboratories and principal manufacturing facilities are located in this new 37 acre plant in Northlake, Illinois, a suburb of Chicago. Branch factories are located in Genoa, Illinois and Waukesha, Wisconsin. These modern facilities are devoted exclusively to t he manufacture of a complete line of automatic telephone equipment, electrical control components and systems. COPYRIGHT ©1964 AUTOMATIC ELECTRIC COMPANY TCI Library | www.telephonecollectors.info LE ICH TYPE 40 AND TYPE 80 P-A-B-X . ~•o t • •• Figure 1. The Type 40 P-A-B-X. 1. INTRODUCTION This Technical Bulletin covers both the Leich Type 40 and Type 80 private automatic branch exchanges, (P-A-B-X). The features and services provided by these two P-A-B-X's and the method of operation are very similar. The principal difference is the capacity of each P-A-B-X and the amount of equipment required to meet the capacity. The T y pe 40 P- A -B-X (figure 1) is an all relay switching, common control, and commonbattery type P-A-B-X capable of ser v ing 40 loc a l lines (a maximum of 39 lo c al lines when equipped with the attendant's turret). The Type 40 P-A-B- X operates at a voltage range of 44 to 56 volts with a common-battery central office, and can also be adapted to work into a magneto office. The Type 40 P- A -B- X c an be equipped with a total of 6 local links, 10 central offic e trunks (city trunks), 2 attendant's information trunks, and an ,attendant's P-A-X line. The Type 40 P-A-B-X uses a standard Type 80 or 90 tel e phone a s station apparatus, e xc e pt in t he case of stations arranged for power failure transfer service where a T y pe 80 or 90 telephone equipped with a grounding pushbutton may b e required. The T y pe 40 P- A -B-X TCI Library | www.telephonecollectors.info 1 uses two-digit lo cal dialing, with single-digit access to certain features such as city trunks or attendant's information trunks. The Type 40 P-A-B-X can be operated with or without the attendant's turret. The Type 80 P-A-B-X (figure 2) is an all relay switching, common control, and common battery type P-A-B-X capable of serving a maximum of 80 lo cal lines, (a maximum of 79 local lines when equip ped with the attendant's turret). The Type 80 P-A-B-X operates at a voltage range of 44 to 56 volts with a commonbattery central office and can also be adapted to work into a magneto office. The T ype 80 P-A-B-X can be equipped with 9 local links, 18 c ity trunks (with optional equipment for 3 additional links or 2 additional city trunks), 4 attendant's information trunks, and an attendant's P-A-X line. The Type 80 P-A-B-X uses standard T ype 80 or 90 telephones as station apparatus with the exception of stations arranged for power failure transfer service where a Type 80 or 90 telephone equipped with grounding push- button may be required. The Type 80 P-A-B-Xuses three digits for lo cal dialing with single-digit access to certain features. The Type 80 P-A-B - X can be operated with or without the attendant's turret. The Type 40 and the Type 80 P-A-B-Xhave the same specified operating limits. The city trunk loop limit is eith er the central-office loop limit or 1500 ohms, whichever is less. The specified line loop limit is 1000 ohms, excluding the station instrument. At stations assigned to power failure transfer service, or night answer service, the sum of the central-office trunk loop and the loop of the P-A-B-X station assigned to the trunk must not exceed the central-office loop limit. 2. STANDARD FEATURES AND OPERATING SERVICES b. The trunks of the Type 80 P-A -B- X can be split into three groups. Local stations can then be arranged to fall into one of the three following c l assifications: Restricted - local station is restricted from accessing all three trunk groups. Non Restricted - local station can access all three trunk groups. Partially Restricted - lo cal station can access 1 or 2 of the three trunk groups. 2 .2 Trunk Transfer A local station can transfer a trunk call to a second local station by dialing the digit "l ", to place the trunk call on ''hold'', and then dialing the digits of the desir e d local station. When the original local station disconnects, the trunk call is automatically transferred to the second local station. 2 .3 Consultation Service If a local station is engaged on a trunk call , dialing the digit ''1'', places the trunk call on ''hold''. The original loc al station can then dial a second local station and converse without the party on the city trunk being able to hear the conversation. To return to the trunk call, after the called station hangs up, the original station again dials '' l''. 2 .4 Two-Station, One-Trunk Conference Service two-local station, one-trunk conference service can be had by connecting a special ''C'' wire at the city trunk. When a local station desires to bring a second local station into a conference with a city trunk, he dials the digit 1, then the digits of the desired local station. The second station is then informed not to hang up, the firststationagaindials "1" to set up the conference. A 2 .5 The following paragraphs outline the standard features and operating services of the Type 40 and 80 P-A-B-X's. 2 .1 Arranging Trunk Groups a. The trunks of the Type 40 P- A -B- X can be split into two groups. The lo c al stations can then be arranged to fall into one of the two following classifications : Restricted - local station is restricted from accessing trunk groups. Non Restricted - lo c al station can ac cess all trunk groups. 2 Power Failure Transfer A number of local stations corresponding to the number of city trunks can be arranged to transfer automatically to preassigned c ity trunks should a commercial power failure occur. Stations assigned to power failure service must be equipped with a grounding push-button when the city trunks are arranged for outgoing loop dialing with ground seizure at the distant end. To initiate a call during a power failure, the grounding push-button at the local station must be depressed before the desired party's number can be dialed. Incoming calls during a power failure are routed directly and autom a tically from the c ity trunk to its corresponding preassigned local station . TCI Library | www.telephonecollectors.info Figure 2 . The Type 80 P-A-B-X. 2 .6 Universal Night Answer When the night key (N) on the attendant's turret is operated, incoming trunk calls will cause a separate night signal or buzzer on the turret to sound. The call may be answered from any local station by dialing the digit assigned to night answer, usually the digit 8. If necessary the call can then be transferred to another local station. 2. 7 Predetermined Night Answering Certain city trunks can be connected directly to preassigned local stations when the night key on the attendant's turret is operated. In this case the call cannot be transferred to another local station. Outgoing calls are originated from these stations as covered in paragraph 2 .5. 2 .8 Attendant's Busy Override An attendant, attempting to reach a lo c al station upon receiving a busy indication, can, by operating the break-in key (BK), c ut in on the busy line and inform the desired party of an important incoming call. 3. OPTIONAL SERVICES The following paragraphs discuss the optional equipment that can be incorporated into the Type 40 or 80 P-A-B-X. Consideration must be given to the equipment mounting fa c ilities of either P- A -B-X before adding any optional equipment. Section 4 covers the various com binations of equipment possible with the Type 40 or Type 80 P-A-B-X. 3.1 Code Call Circuit The code call circuit provides 36 signal codes which can control audible signals. These signals are used for notifying parties on the premises , but out of hearing of their regular station instrument, that a call is waiting for them. TCI Library | www.telephonecollectors.info 3 To sound a particular party's code signal, any local station or the attendant may dial the digit assigned to the code call c irc uit (usuaHy "6"), then the digits of the desired code signal are dialed. The longest signal code to be ~ou~ded is 6 as the 36 codes comprise all combinations of the digits 1 to 6. To answer, the signaled party dials 31 (Ty pe 40 P-A-B_-X) ?r 231 (Type 80 P-A-B-X) from any station; lines 31 and 231 are reserved for code call answer. c ode call supervisory lamp which will fla~h at 60 ipm when the signaled party answers, 1s mounted on the attendant's turret control panel. This l am p flashes when the attendant initiates the code call signal using the attendant out dial trunk and is required to answer a city trunk call before the c ode call is answered. \Vhen a local station uses this circuit , the lamp will not flash. A 3 .2 ''Meet-Me'' Conference Circuit This circuit provides a ''Meet-me'' type conference for a city trunk and three local stations, or four local stations. The attendant or a lo cal station can set up a' 'meet-me'' type co nfer ence involving a ci ty trunk. If a loc a l station is setting up the co nference which includes a c ity trunk, he di a ls the digit assigned to meet-me conference service and then replaces the handset. The c ity trunk is au_tom'.1tically transferred to the conference circu i t. The local station must then notify the other parties who are to take part in the co nfer e n ce to dial the number assigned to the conference c ir cu it. Setting up a ''meet-me'' type c onference by the attendant will be discuss ed in section 8. 3 .4 Executive Override Circuit This circuit allows an assigned local station to override a busy condition either automatically ·or by dialing a suffix digit. An option can be provided to supply a tic k tone to the busy line so the parties will be aware of the override condition. 3 .5 Dictation Control Link This circuit permits the connection of local stations to centrally located dictation equipment. A dictation control link must be supplied for each dictation machine provided. 3.6 Public Address Cut-In Announcements can be made over a public address system from any local station by dialing the access number and making the announ ceme nt. 3. 7 Paging Telephone A paging telephone is co nnect e d through a speaker in a central loc a tion, a microphone is also located in the same area. This equipment allows a worker to carry on his normal work, and maintain a telephone conversation b y listening to the speaker and talking towards the microphone. 3 .8 Toll Diversion Adapter 3.3 City Trunk Storage This circuit a llows lo cal stations to store up to a maximum of three incoming calls when the attendant's turret is set up for univers a l night answering service or when an a ttend a nt's turret is not provided. When an incoming trunk call is answered by a local station, and an attempt is made to transfer the call to another loc al station th e digit 1 is dialed to place the trunk call on "hold", while the desired party's number is dialed. If the call ed station is busy, the call ing station depresses the hoo ksw it ch a nd notifi es the city trunk party th at hi s party is busy. If the call ing party desires to wait, the lo cal station dials the digit 1 and then the digit assigned to c ity trunk storage . . This procedure can be repeated to store a maximum of three call s. To remove calls from storage, the digit or digits assigned to city trunk storage release must be dialed. Calls must be taken out of storage in the same order they are placed in storage. This feature can prove extremely useful; for e xample a night watchman who cannot rema in 4 at one assigned station, but must be free . to move about to perform various duties. With this feature he can answer, transfer, hold, and place calls in storage from any local station. This c ircuit adapts an associated city trunk for toll diversion and toll restriction service. A local (nonrestricted ) station attempting to place a toll call w ill be diverted back to the atte ndant. The toll diversion a dapter is inserted between the trunk circ uit and the termination of the trunk le a ds to the central office. 3 .9 Tie or FX Trunks Tie trunks to a distant P-A-B-X or P-B-X can be provided. Consultation and conference features can be provided on tie trunks. FX (foreign exchange) trunks can be furnished to a central off i ce, other than the central office serving the P-A-B-X. 3 .10 Rotary Trunk Selection This circuit provides a max i mum of 2 groups of 3 lo c a l lines each, 1 group of 5 l ocal li nes and 1 group of 6 local lines or comb i nations of TCI Library | www.telephonecollectors.info these as required and is used to automatically hunt for an idle line within the group. The three stations do not h ave to be numbered consecutively, however, the second digit of the first pilot number of both groups must be the same. For example, group one may be assigned to hunt over lines 41, 56, and 67; and group two may hunt over lines 51, 64, and 72. Notice that the second digit of the pilot number of the two groups is the same. 3.11 Central-Office Trunk Adapter for 2-Way Ringdown Signaling This c ircuit is capabl e of converting a maximum of three city trunks for 2-way ringdown signaling. 3.12 Message Waiting Service Message waiting service can be provided w ith the Type 40 and 80 P-A-B-X's. To equip a P-A-B-X for message wai ting service, a message waiting turret must be provided and the telephones served by this message waiting turret must be equipped with a message waiting l amp. The message waiting turret is similar in design and size to the attendant's turret. The message waiting lamp is a neon lamp mounted below and to the right of the dial. 4. MOUNTING ARRANGE MENTS The following paragraphs and tables outline the various equipment mounting arrangements possible with the Type 40 and 80 P-A-B-X's. Tables A and C list the standard equipment provided and also the bank outlets, relay bar positions · and switch positions required by the standard equipment. Tables B and D list the optional equipment that can be provided and also the bank outlets, relay bar positions and switch positions required by the optional equipment. Th e relay bar shown in figure 3 (link relay bar) is ready to be jachid-in to its mounting position. The jacks are located at the rear of the metal case. When the re lay bar is jacked-in to its mounting position, these jacks will make contact with the jack strip lo cated at the mounting position. All relay bars are equipped with the same type of metal case and jacks. The metal case en c l oses the wiring and various components mounted at the rear of the re lay bar. The cross point switch shown in figure 4 can function as a finder, connector or trunk switch. The switch must be mounted in the switch shell before metal contact rods can be inserted. 4 .1 Mounting Arrangements for the Type 40 P-A-B - X The equipment com prising the Type 40 P-A-B-X is assembled in a three-shelf arrangement and completely enclosed in a metal cabinet 48" wide, 72" high and 15" deep. The cabinet is finished in gray lacquer. The cabinet has two lift-off type hinged doors both front and rear, which when opened allow easy access to the equipment mounted within (figure 1) . TABLE A E q uipment 39 Local l ines: 2 link re lay bars 2 selection control relay bars common equipment 1 line equipment re lay strip * power failure transfer circuit * Atte ndant's turret: 2 attendant's information trunks turret position turret register ** 10 city trunks Bank Outlets Switch Positions Relay Bar Positions 12 2 2 2 - 39 2 1 1 - 10 10 10 TOTAL (used) 52 22 18 Balance 8 4 3 *These are relay strips, not jack-in type relay bars. Their mounting positions are not considered relay bar positions. **Turret register circuit is mounted on the power failur e transfer relay bar. TCI Library | www.telephonecollectors.info 5 TABLE B Bank Outlets Switch Positions Relay Bar Positions ''Meet-me'' Conference * 1 3 1 Executive Link 1 1 1 Optional Equipment Dictation Control (on line) 1 - 1 Dictation Control (on switch) - 1 1 City Trunk Storage 6 - 1 Public Address Cut - In ** 1 - - Toll Diversion Adapter - - 1 Code Call 2 - 1 * "Meet-Me" conference is mounted on the attendant's trunk relay bar. ** Public Address Cut-in adapter must be mounted externally. a. The three equipment shelves are designated B, D, and E. Shelf B contains the Leich crosspoint switch shell shown in figure 5, which houses 6 finder switches, 6 connector switches, and ten trunk switches. In all, the switch shell has available 26 mounting positions des i gnated Bl through B26. The finde r and connector switches are always mounted in pai rs. The number of 7 L- Ir{- ', l .~ . .t..., ,I I ~ ; I , ~• r ~ , .;_;· ,i:......L.,- , T;' r ! f !I ~ t I I ' r '" '' I "-! I! I < ~I Lr rl.i I Figu re 3. R elay bar. 6 Figure 4. Cross/Joint swi t ch , TCI Library | www.telephonecollectors.info tro l c ircu it s; each selection co nt ro l re l ay bar serves three link c ircuits . Position E4 is oc c upied by the attendant's trunks and meet-me c onference trunk. Position E5 is occupied by the turret position c irc uit. If the attendant's turret i s not supplied this can be used as an optional position. Position E6 is occupi ed by the power failure transfer and t urret register c ircuit. Position E7 is occupied by the line e quipment re l ay strip. The line equipment relay strip contains 80 relay s, (40 line relays and 40 cut-off relays) and serves 40 lo cal lines. Each local line is served by an individual line and cut-off re lay. these switches required is determined by the number of links supplied. Each link requires one finder and one connector switch. The trunk switches are mounted to the l eft and right of the finder and connector switches. The amount of trunk switches required depends upon the number of city trunks supplied . Each city trunk requires one trunk switch. The four optional switch positions can be used to house the switches required by the optional equipment listed in Table B. b. Shelf D has available 16 jack-in relay bar pos i tions designated Dl through D16 (figure 5). Posit ions D 1 and D2 are occupied by the two link circuit relay bars, each link relay bar contains re l ay equipm e nt for three link circuits. Positions D3 through D 1 2 contain the ten city trunk relay bars. If less than ten city trunks are provided, the remain ing positions can be used to house optional equ ipment. Position Dl 3 is occupied by the interru pter and the trunk and code call control circuit. Positions D14, D15 and D16 are optional positions. c. Shelf E has 5 j ack-in re l ay bar po s itions designated E l through E5. Pos ition s E6 and E7 house the line equipment and power failure transfer circuit; these are not jack-in relay bar positions (fi gure 5). Shelf E also contains the fuse panel and the power supply. Position El is occupied by the finder guard circuit. Position E2 and E3 are occupied by the selection con- 4.2 Capacity of the Type 40 P-A-B- X The three factors in determ ining the over-all equipment capacity of the Type 40 P - A-B-X are total bank outlets, switch positions, and re l ay bar positions provi ded. The T y pe 40 P-A-B-X provides 60 bank outlets, 26 switc h positions and 21 relay bar positions. The Type 40 P-A-B - X shown in figure 5 contains all the standard equ i pment i nclud ing the equipment associated with attendant's turret and provides 39 l ocal lines , 1 attendant's P-A-X line, 10 city trunks and 2 attendant's information trunks. Table A lists the capacity of the Type 40 P-A-B-X that h as been utilized. Table B lists the optional equipment availabl e for the Type 40 P- A -B-X. When planning the use of optional equipment keep in mind the P-A-B-X capacity listed in Table A. T abl e A lists the capacity of the P-A-B- X that has been utilized and also the bank outlets, switch <J> <J> om:i::r l"Tl~ r ,, CD ffl r ,, ,, ~ 1-3 DI SELECTION CONTROL ( LINKS 1- 3 ) E2 LINKS 4-6 02 SELECTION CON TROL (LINKS 4-6) E3 TR UNK I 03 E4 " 2 04 3 05 FINDER GUARD ATTENDANTS TRUNKS AND CONFEREN CE ... CD, El LINKS TURRE T POSI TION E5 " POWER FAILURE TRAN SFER TURRET REGISTER E6 " 4 06 LINES 20 - 50 E7 " 5 07 " 6 08 FUSE PANEL POWER PLANT " 7 09 " 8 010 " 9 Oil " 10 INTERRUPTER , TRUN K SCOOE CALL CONTROLS OP TI ONAL END GUIDE OPTIONAL llCONF. 31 TRUNK 9 7 " 5 " 3 " I " H LINK' F LINK 5 CONNECTOR LlNK ~ t-lNUt:.H ~ I TOR TUR BANK JACK LINK 2 FIN DER IN K2 ONNECTOR LINK4 FINDER LINK4 LINKS FINDER LINK 6 CONNECTOR 012 013 014 OPTIONAL 015 OPTIONAL 016 £ 4 6 " 8 " IL " (CONF. 2 1 <CO NF. 4) EN D GUIDE " TERM. El..OCKS IN REAR 72" B25 M /S 821 819 B17 I B15 813 RI 89 "' B5 83 Bl 82 84 B6 tltl BIO 812 B14 RIIS B18 8 20 M N B24 826 __J Figure 5. Mounting arrangements for Type 40 P-A-B-X. TCI Library | www.telephonecollectors.info 7 TABLE C Equipment Bank Outlets Switch Positions Relay Bar Positions 18 3 3 4 - 74 local lines* 3 link relay bars 3 se lectio n control re lay bars comm o n equi pment 2 line equipment relay strips ** power fai lure tr ansfe r circu it ** 74 Attendant's turret: attendant's trunk circuit turret position cir c uit turret register c ir cuit *** 4 1 6 city trunks 18 18 18 TOTAL (used) 96 36 30 Balance 3 4 6 1 1 - *Lines 286 - 289, 280 strapped for consultation -t ransfer service on city trunks 16-20, may be used for lo cal lines if these trunks are n ot u sed. **These are relay strips, not jack-in type re lay bars. tions are not co n sidered re l ay bar positions. Their mounting posi- ***T urret register circuit is mounted on the miscellaneous common equipment relay bar. positions, and re l ay bar positions availab l e for mounting optional equipment. These availabl e positions wi ll determine the type and amount of optional equipment that can be used with this P-A-B-X. If more optional features are required than there are optional bank multiple outlets or swi tches available, use one of the following solutions: a. Decrease one lo cal line multiple outlet required. per each bank b. Decrease one trunk for each switch and bank multiple outlet required. 4 .3 Mounting Arrangements for the T y pe 80 P-A-B-X The equipment co mprising the Type 80 P - A -B- X is assemb l ed in a three-shelf arrangement and completely enclosed in a m etal cab inet 72" w ide, 72'"' high and 15" deep (figur e 2). The cabinet has two lift -off hinged doors and a snap-in ce ntral panel both front and re ar. The cab inet is finished in gray l acquer. a. The three she l ves shown in figure 6 are designated B, D, and E. Shelf B co ntains the crosspoint switch shell wh i ch is ca pable of hou s ing 40 switches and provides 100 b a nk outlets. Th e 40 switch position s within 8 the crosspo int switch are designated Bl through B40. The crosspoint switch shell in figure 6 contains 9 finder and 9 c onne ctor switches, 18 trunk switches, and 4 optional switch positions. The amount of finder and connector switches required depends upon the amount of links supplied. Each link requires one find er and one connector switch, these are always mounted side by side. The amount of trunk switches required depends upon the number of city trunks supplied; each city trunk requ ires 1 trunk switch. The 4 optional positions can be used to house the switches requi red by the optional equipment list.e d in Table D. b. Shelf D contains 24 jack-in relay bar positions, designated Dl through D24 (figure 6). Positions D l , D2, and D3 are occupied by the three link c ircuit relay bars, each link re l ay bar c ontaining re lay equipment for three link c i rcuits. Pos ition D4 can be occupied either by the link c irc uit relay bar c ontaining links 10 through 1 2 or by c ity trunk No. 20. If neither of these two relay bars are provided , this position can be used as an optional position. Position D5 is oc c upied by c ity trunk No. 1 9 if pro v ided. If trunk No. 1 9 is not provid e d, this can be used as an optional position . Positions D6 through D23 are occupied by city tru nk s No. 1 through No. 1 8. If l ess than 18 city trunks are pro vided, unused TCI Library | www.telephonecollectors.info 11 en :c ! l'TIITI .,, :c .,, r -~ '~ CJ) Cill'TI OITI .,, r r - .... SELECTION CONTROL NO.I El LINKS 1-3 DI SELE CTION CONTROL N0.2 E2 LINKS 4-6 ~ SELECTION CONTROL NO. 3 E3 LINKS 7-9 D3 OPTIONAL E4 OPTIONAL ES OPTIONAL OPTIONAL 05 TRUNK NO. 18 E6 OPTIONAL ~ OPTIONAL E7 17 " D6 07 . END GUIDE LINK I FINDER 837 LINK 3 FINDER 835 LINK 3 CONNECTOR 8-33 LINK 5 FINDER 831 LINK 5 CONNECTOR 829 LINK 7 FINDER 827 LINK 7 CONNECTOR 825 LINK 9 FINDER 823 LINK 9 CONNECTOR 821 OPTIONAL ATTENDANT TRUNKS TURRET POSIT ION EB 16 " E9 15 " DB a 817 TRUNK N0 . 15 815 13 Bl3 II BIi D9 " SELECTION ROUTING EIO 14 DID E II 13 DI! E12 TRUNK N0.12 012 9 89 7 B7 5 BS 3 B3 TRUNK NO. I Bl .... "'= FINDER GUARD (I) J> (/) FUSE PANEL (26 ) 819 TRUNK 17 OR OPTIONAL MISC. COMMON TURRET REGISTER 839 LINK I CONNECTOR TRUNK N0.2 B2 POWER FA ILURE TRANSFER E13 TRUNK NO. II Dl3 4 84 6 86 LINES 211 TO 240 E14 10 Dl4 8 88 10 BIO 9 DIS 12 EIS e TRANSISTORIZED POWER PLANT 12 AMP. BATT. ELIM . 6 CHG . 7 1/2 W. RINGING GEN. 251111 .W. TONE GEN. TRUNK N0.14 Dl6 7 Dl7 6 Dl8 5 Dl9 4 D20 3 2 D21 D22 INTERRUPTER a TRUNK CONTROLS 72" D23 812 814 TRUNK 16 OR OPTIONAL 816 TRUNK 18 OR OPTIONAL BIB OPTIONAL B20 822 824 LINK 8 FINDER 826 LINK 8 CONNECTOR 828 LINK 6 FINDER 830 LINK 6 CONNECTOR 832 LINK 4 FINDE" 834 LINK 4 CONNECTOR 836 LINK 2 FINDER LINK 2 TRUNK NO.I i BANK JACK FUSE PANEL (26) IT1 LINES 251 TO 280 i CONNECTOR END GUIDE 836 840 D24 -------------------------------91 Figure 6. Mounting arrangements for Type 80 P-A-B-X. TCI Library | www.telephonecollectors.info 9 TABLED B a nk Outlets Switch Position Relay Bar Position ''Meet -m e ' Confe r e n ce 1 3 1 Link Relay Bar (links 10-12) - 6 1 Link Se l e ction control re lay bar - - 1 Code Call 2 - 1 City Trunk 1/ 19 1 1 1 City Trunk #20 1 1 1 Executive Link 1 Optional Equipment - 1 Di ctation Control - trunk on Line 1 - 1 Di c tation Contro l-trunk on Switch - 1 1 1 City Trunk Storage 6 - Public Address System * 1 - - Toll Restriction Adapte r - - 1 *P ublic Address adapter is mounted externally. positions can be used as o ptio nal positions. Position D24 is occupied by the interrupter a nd trunk control circuit. c. Shelf E contai ns 12 jack-in positions designated El through E12 (figure 6 ). Positions E13, E14, and E15 house the line equipment and power failure transfer c irc uits, these circuit s are mounted on relay strips , not re lay bars. Positions El3, El4, and E 1 5 are not cons id ered re l ay bar positions. Pos i tions El, E2, and E3 are occupied by the three se le ction control c ircuits. A se lection control circuit must be provided for eac h link relay bar supplied. Position E4 is occupied by se l ec tion control c irc u it No. 4, when links 10 through 12 are provided. When links 10 through 12 are not provided, E4 can be used as an optional position. Pos itions E5, E6, and E7 are optiona l positions. Position s E8 (4 attendant's trunks), and E9 (attendant's turret), are associated w ith the attendant's turret a nd can be used as optional positions if the atte ndant 's turret is not supplied. Position E l 0 is occupied by the miscellaneous common and turret register c ircuit. The miscellaneous common equipment need be provided onl y if the attendant's turret is not supplied. Position Ell is occupied by the selection routing circuit. Position E12 is occupied by the finder g uard c i rcuit. Position El 3 is occupied by the power failure transfer circu it. Positions E14 and E15 are occupied by the lin e equ ipment relay strips. Each local line is served by an individual line, and cut -off relay whi c h i s mounted on the lin e equ ipm ent 10 re l ay strips. Each line equipm ent re lay strip contains 80 relays, (40 line re lays and 40 cut-off relays) and serves 40 local lines. Therefore two lin e equipm ent re lay stri ps are required to serve 80 local lines. 4.4 Capacity of the Type 80 P-A-B-X As in the case of the T ype 40 P-A-B-X, the three fact ors determining the over-all equipment capac i ty of the Type 80 P-A-B-X are the total bank outlets provided, switch positions, and relay bar positions avail able. The Type 80 P-A-B-X provides 100 bank outlets, 40 switch position s, and 36 relay bar positions. The Type 80 P-A-B - X shown in figure 6 contains the standard equipment, in c luding the equipment associated with t he attendant's turret and provides up to 79 local lines, 1 attendant's P-A-X line, 1 8 c i ty trunks, and 3 attendant's inform ation trunks. Table C li sts the bank outlets, switch positions, and re l ay bar positions utili zed by this standard equipment. Table D lists the optional equipment available for the Type 80 P-A-B-X. When planning th e use of optional equipment keep in mind the P-A-B-X capacity listed in Table C. Table C illustrates the capacity of the P-A-B-X that has been utili zed and also the bank outlets, switch positions, and re lay bar positions available for mounting optional equ ipment. These available positions w ill determine the type and amount of optional equ ipm ent that can be used w ith this P-A-B - X. Also see paragraph 4.5. When more optional features are required than there are optional bank mult ipl e outlets or TCI Library | www.telephonecollectors.info switches available, apply the following solutions: a. Decrease one local line multiple outlet required. per each bank 0 l ~ ~ ~ • ? •~.J"(..jr};; :.f " ~ • ::, 0 • OJ ,:> b. Decrease one trunk for each switch and bank multiple outlet required. 4.5 Type 40 and 80 P-A-B-X Auxiliary Trunk Bay The Type 40 and 80 P-A -B- X auxil iary trunk bay shown in figur e 7 is designated to be used as an equipment overflow bay for the Type 40 or Type 80 P-A-B-X. The auxiliary trunk bay provides 12 jack-in relay bar positions for mounting optional equipment. With the addition of the auxiliary trunk. bay, the total relay bar positions provided by either P-A-B-X is increased by 12, however, the switch and bank outlets provided by either P-A-B-X is not increased. 5. THEORY OF OPERATION Connection between the calling line and the called line is established through the link circuit. The link circuit consists of a finder switch which makes connection to the calling line under control of the line relay serving the calling line by way of the finder guard c i rcu it and link selection c ontrol circuit. A link relay circuit cons isting of six relays receives the dial pulses and transmits them to the associated selection co ntrol circuit. A connector switch then selects the called line under control of the link relays and the attached selection control circuit. 5 .1 Line Equipment Each local P-A-B-X line is served by a line relay and a cut-off relay. The line relay , designated LR, operates when the handset is lifted off-hook and controls seizure of a link. The cut-off relay, designated CO, operates on incoming calls to disconnect the line relay whenever the line is c onnected to a link or trunk. 5 .2 Finder Guard The finder guard prevents interference between lines which attempt to simultaneously land (seize) by allowing the lowest-numbered line to land first. The finder guard also provides a preference circuit to maintain service under various faulty conditions. If a line has trouble in landing, a relay will release and shift the preference circuit so that a high-numbered line can land ahead of a lower-numbered line that is in trouble. FiguYe 7. Auxiliary trunk bay, 5 .3 Link Selection Control After a line has landed in the finder guard, information is passed to the selection control circuit causing the calling line to select an idle link. Three links are connected to each selection control and no other links use it; for example, links 1, 2, and 3 are associated with selection control circuit No. 1. The link holds the selection control from the time the calling party seizes the link and selection control, until the connection to the called line, trunk group, or to a special service feature is complete. The selection control is then dis- TCI Library | www.telephonecollectors.info 11 engaged from the link, and prepares to accept another call. conductor, although four conductors are required in the P-A-B-X for each line. Approximately 8 seconds are allowed for the calling party to dial the first digit . If no dial pulses are received within this time, the selection control causes the link to return busy tone to the calling party and also aisengages itself from that link and prepares to accept another call. This also holds true in the case of two-digit numbers for the maximum time allowed between dialing of the first and second digits, and also on threedigit numbers for the maximum time that is allowed between dialing the second and third digits. Because the finders and connectors must be able to access any one line out of the 80 lines, the total lines are divided into tens selections and units sele c tions, corresponding to the tens and units digits of the assigned line number or code. The tens selection selects that line group which inc ludes the desired line, a nd the units selection selects one of these ten lines. Incoming calls engage the selection controls and links in rotation. Assuming that all links and selection controls are idle, the first call will seize selection control No. 1 and link 1; the second call will seize selection control No. 2 and link 4 ; in the Type 80 only, the third call will seize selection control 3 and link 7. With this condition all three selection control c ircuits of the T y pe 80 and the two selection control c ircuits of the Type 40 have been utilized and a reset condition occurs so that the next call that attempts to land will seize selection control 1 and link 2. 5 .4 Selection Routing P-A-B-X Only) Circuit (Type 80 The selection routing circuit is arranged to absorb the prefix digit of lo cal station codes. Although the Type 80 P-A-B-X uses threedigit local codes, only two digits are required to complete a connection through the connector switch. After absorbing the prefix digit, this circuit then routes the tens and units digits to complete the selection. The selection routing circuit also provides full, partial or nonrestricted service to trunks, and also ro uting for special single-digit features. 5 .5 Selection Methods Both the Type 40 P-A-B-X and the Type 80 P-A-B-X engage a finder switch to find the calling line and an associated connector switch to connect it to the called line. Each finder and connector switch must have access to each of the 40 or 80 lines served by the P-A-B-X. A sufficient number . of finder and c onnector switches should be provided to handle the demands for service during the heavy tr a ffic hours of the day. For purposes of example, figure 8 schematically illustrates two finder switches and two connector switches of a 80-line P-A-B-X. Only nine of the 80 lines are shown, in order to present a picture of the switch more clearly. Each lo cal station is represented by a singl e 12 Each switch has 10 tens-lifts, actuated by armatures associated with the vertical co ils at the top and bottom of the switch. Eight of these tens-lifts (10-80) are associated with line circuits and two (90- and 00) are available for spe c ial features. To make a selection, one of these tens-lifts is operated by its armature to actuate the bank spring finger into contact with the multiple bars of ten lines, only three of which are illustrated. This establishes connections from ten lines out of the 80, one to each of the ten bank springs in that switch. To pick one line out of these ten, eac h switch ha s ten units-lifts, actuated by armatures associated with the horizontal coils at the front of the switch. Operating one of these unitslifts causes the eleventh, or front finger of the bank spring on that units level to make contact with the switch bus conductor. Assuming that line 31 is calling and that finder 1 is seized for the call, tens-lift 30 in this finder is operated to connect lines 31-30 to the bank springs of the swi t c h, and units-lift 1 is actuated to connect its bank spring fingers to the switch bus conductor. The other nine bank spring sets do not complete a circuit, as all potential co nne ctions remain open at the unoperated units-lift contacts. Line 31 is now connected to the link associated with that particular finder. When the desired number is dialed, the link functions to cause operation of a tens-lift and a units-lift in the connector. Assuming that 23 is dialed, tens-lift 20 functions to connect lines 21-20 to the bank springs of the connector, thus completing the connection from the finder by way of the link and connector to line 23 . 5 .6 City Trunk The city trunk circuit along with a trunk switch connects the P-A-B-X to a common battery or automatic central office. Local stations on restricted lines cannot dial the c ity trunk di rec tly to make a n outgoing call. These stations must dial the attendant over an attendant's information trunk, a nd ha ve the attendant make the call for them. These calls can then TCI Library | www.telephonecollectors.info FINDER I CONNEC TOR f\ CONNEC TOR 2 30 30 r... ' 20 ' ARMTA\NUSRES~ FINDER 2 30 JO 20 ' ' ' ' 10 10 SWITCH BUS CONDUCTORS ' 20 20 ' r. . 10 IO ' L\f\lE MUL T IPLE ' BARS"~ 31 "' 21 II ~ "' "'- ' -\. BANK SPRINGS ~I LINES - ::; 32 22 12 13 '\.' '\., ~ ' ~w ~ ,_ -=-~ 3 1l r ~ \. ' ' ' LINK RELAYS ~ I ,., ~ L " ~I ;:::: TO O THER FINDERS ANO CONNEC TORS A ,·, ' = =- ~ '-., .... . I ~ ~w t::; '\. " I L-----1 ::; ~ -=- I, 3 UNITS ARMATURES "'- _=: ~I ,= ~ '\., r..., ~ I ' '-., ,, s;;::::; ~ '\ I "' ' ~ .. = '\. "' I " ~2 23 =~ "' r-, = ' I = ;:::: '\., " ' '-., '\ I I " "" = -" = " ' r. ~ I• = ,,;;- - ~w '\., "' =:- ' 'i 3 l ', ' ~ "'-=" >,. :3 3 " \ \. ~ 13 ' \ ' LINK RELAYS 1-- Figure Bo Crosspoint switch diagramo b e extended to th e local stationo Stations on nonrestricted lines may dial the trunk directly to make outgoing calls. 6 . SELECTION SCHEME BLOCK DIAGRAM Using the block diagram in figure 9, we will trace three different types of calls through a T y pe 80 P-A-B-X: a call between two local stations, an outgoing trunk call from a local station, and an incoming trunk call through the attendant's turret to a local station. 6 .1 S t a tion 1 dials, se nding pulses through the link c ircu it to the link selection co nt ro l wh i ch counts them and pa sses th e information to the selection routing circuit. The routing circuit then controls the selection of station line 2 in the link connector switch. The selection control circuit tests the line to determine if it is busy or idle, then signals the link circuit to return busy tone or switch through and signal the called station. In either case, the selection control circuit disengages from the link circuit and becomes available to serve either of its two remaining associated lines. Local Call - Station to Station 6 .2 Outgoing T