Historical Document · 1971
Plessey Telecommunications Catalogue (1971)
132 pp. PAX, PABX, PMBX and rural exchanges; uniselector-based systems
Historical Document · 1971
132 pp. PAX, PABX, PMBX and rural exchanges; uniselector-based systems
c () e N T � PLESSEY TELECOMMUNICATIONS CATALOGUE ���� Contents Introduction General Information Obsolete Products Section 1 Private Automatic Exchanges Section 2 Private Automatic Branch Exchanges Section 3 Private Manual Branch Exchanges Section 4 Rural Exchanges Section 5 Telephones Section 6 Miscellaneous T s General Information Enquiries and Orders Commercial and technical enquiries and all orders for products des cribed in this catalogue should be directed to the following address which appears on all catalogue sheets: The Plessey Company Limited, Telecommunications Group, Private Systems Division (Dept. LA), Beeston, Nottingham NG9 1 LA, England. Telephone: Nottingham (0602) 254831 Telex: 37201 Each catalogue sheet includes specific ordering information. Dimensions and Weights Dimensions and weights are given, where possible, to assist shipping estimates. Payment, Terms and Delivery Conditions These are subject to our standard conditions of contract, or to special conditions which may be agreed at the time of quoting. Packing Cases Packing cases will be credited in full if returned in good condition within 14 days, carriage paid, and duly advised. Return of Goods Goods must not be returned without our consent. Parts and Accessories A booklet containing lists of components for the ordering of parts is usually supplied to the customer when goods are despatched. Otherwise a booklet can be obtained on application. Alternatively, replacements may be ordered by quoting the code number stamped on the original component. Accessories may be ordered by naming the article and stating its code number. Claims Claims for damaged goods must be made on the carriers within the time specified in the contract. Improvements in Design In keeping with its policy of continually striving to improve its products, the Plessey Telecommunications Group reserves the right to change the design of, or withdraw, any item in this catalogue. Illustrations Illustrations are not binding, owing to improvements made from time to time. © 1971 The information contained herein is the property of and is supplied in confidence by The Plessey Company Limited and must not be reproduced in whole or in part without the written permission of the Company. PLESSEY Telecommunications Printed in England The Plessey Company Limited, Private Communication Systems, Beeston, Nottingham, England NG9 1 LA. Telephone: Nottingham (0602) 254831. Publication No. 7204/1 � Telex: 37201 ZB 8/·5K/1·73 Introduction This catalogue provides telephone administrations and similar organizations with a quick, easy reference to a range of tele phone equipment, apparatus and systems produced and marketed by Private Communication Systems, part of Plessey Telecommunications. The range is extensive, covering subscribers' apparatus, private systems, rural exchanges and miscellaneous equipment. It does not, however, include Main Automatic Exchange (MAX) equipment, as this is dealt with by Plessey Telecommunications at Liverpool (Strowger and Crossbar 5005 exchanges) and Transmission and Electronic Exchanges, Beeston, Nottingham (TXE2 PENTEX space division electronic exchanges). The catalogue is based on the loose-leaf system, enabling it to be kept constantly up to date by the issue of supplementary or revised sheets so that customers have ready indication of new introductions. Six product-group sections are presented, each separated by a distinctive, numbered card carrying an integral identification tab for quick selection. The philosophy behind this catalogue is simple CUSTOMER SERVICE, a service that combines a willingness to investigate your particular telecommunications problems with the ability to solve them. This service is available to you at the initial stage of an enquiry. If you wish, we will act as your consultant in determining the product or system best suited to your needs. We will also provide full details on relevant matters such as system operation, installation, training, and logistics, and we will carry out surveys and give quotations for one or more systems without any charge whatsoever. This comprehensive service is backed by Plessey Telecom munications' vast experience and accumulated knowledge over 60 years, coupled with advanced design, research, development and manufacturing facilities. By faithful adherence to high stan dards throughout our streamlined organization we get things done quickly, efficiently, and economically, thereby main taining our fine reputation as manufacturers of telecommunica tions equipment second to none. PLESSEY Telecommunications Printed in England The Plessey Company Limited, Private Communication Systems, Beeston, Nottingham, England, NG91 LA. Telephone: Nottingham (0602) 254831. Publication No. 7227/1 Telex: 37201 � ZB29/500/2.73 Transmission and Electronic Exchanges Major Systems Main Products Strowger and Crossbar main and Main Products satellite exchanges: manual TXE2(Pentex)main, dependent and exchanges: international and satellite exchanges. Development, national trunk switching centres: international, national and private marketing and production of automatic telex exchanges. systems and equipment: basic Headquarters: Edge Lane, Liverpool L7 9NW research in digital switching, p.c.m. and s.p.c. Liverpool(051)228 4830 Headquarters: electronic telephone exchange Telex 62267. Beeston, Nottingham NG9 1LA Edwards Lane, Liverpool L24 9HW Nottingham(0602)254831 Liverpool(051)486 4031 Telex627516. Antrim Road, Ballynahinch, Co. Telex 37201. Fleming Road, Speke, Liverpool Down, Northern Ireland. L24 9LJ. Liverpool(051)486 3286 Ballynahinch(0238 56)2339. Telex627329. Dixon Road, Kirkby Industrial Estate, Plessey Telecommunications Liverpool L33 7XR. Liverpool(051) Taplow, Maidenhead, Berkshire 546 3654 Telex62612. Exchange Factory, 39 Cheapside, Maidenhead(0628)23351 Research Limited, Taplow Court, Telex84119. Liverpool L2 2EA. Liverpool(051) Data Communications Sciences 236 9881 Telex627053. Limited, llford, Essex. London(01) 478 3040 Telex23166. Lamberhead Industrial Estate, Pemberton, Wigan, Lancashire Wigan(0942)83341 Telex67598. Pioneer Works, Wigan, Lancashire Wigan(0942)44272 Telex67598. Great George Street, Wallgate, Wigan, Lancashire. Wigan(0942) 47121 Telex67598. Carr Lane, Chorley, Lancashire PR7 3J P. Chorley(02572)5521 Telex67496. North Hylton Road, Southwick, Overseas Operations Headquarters: Edge Lane, Liverpool L7 9NW Liverpool(051)228 4830 Telex62267. Offices and manufacturing facilties in Brazil, Portugal, Ireland, East & Central Africa, Canada, Singapore and Malaysia. Sunderland, Co. Durham Sunderland(08943)4361 Private Communication Systems Telex 53411. Telephones(all types)including Eldon Street, Laygate, South Shields, Co. Durham. South Shields(08943) 4361 Telex53510. Installation Main Products flameproof, and pressbutton types for d.c. or m.f. signalling systems: secretarial, intercom and extension plan systems: Crossbar and Headquarters: Strowger PAX, PABX and rural exchanges: PMBX: telephone Edge Lane, Liverpool L7 9NW equipment accessories: mine Liverpool(051)228 4830 Telex 62267. Regional Offices: London, Home Counties and South East: Burford Road, London E15 telephones and signalling systems and other communications systems. Headquarters, Sales and Contracts: Beeston, Nottingham NG9 1LA London(01)534 4533 Ext. 48 Nottingham(0602)254831 Telex 37201. Telex261676. Midlands: Installation Dept., Tolworth Rise, Surbiton, Surrey Beeston, Nottingham NG9 1LA Nottingham(0602)254831 Ext. 360 Telex37201. North West and North Wales: 95-97 Washway Road, Sale, Cheshire. Sale(061) 973 1788 Scotland, Northern Ireland and North East: 224-228 West Street, Glasgow C5 Glasgow(041)429 3292. South Wales and South West: Marketing: KT5 9NW. London (01)337 6666 Telex 261834. Plessey Communication Systems Limited, Tolworth Rise, Surbiton, Surrey KT5 9NW. 337 6666 London(01) Telex261834. London Branch Office: 9 Dallington Street, London EC1 Sak�London(01)251 1254 Service: London (01)251 0237 New Era Time & Telephone Systems Royal London Buildings, 42 Baldwin Street, Bristol BS1 1PV Limited. Tolworth Rise, Surbiton, Bristol (0272) 24478 337 6666 Beeston Factory Office: Dept. DN, Beeston, Nottingham NG9 1 LA Nottingham(0602)254831 Telex 37201. Surrey KT5 9NW. London(01) Telex 261834. · Due to continual improvement in product design, certain items of apparatus and equipment have be come considerably outdated and are therefore to be withdrawn from manufacture. The most widely used of these obsolete products are listed below, together with references, where possible, to previous catalogues in which these products appeared, and to the nearest equivalent of new design where one exists. Associated spare parts will con tinue to be available, as well as extra equipment for PABX ex tension, but only for a limited period. Customers are therefore strongly advised to assess their long-term requirements for spare parts etc. as quickly as possible and to place a single order accordingly. Obsolete Products Code No(s) Old Catalogue Reference Replacement Product This Catalogue Reference Flameproof, table and vvall, CB type N1397, 98 N1473, 74 Ericsson Telephones Ltd (ETL) Cat. 60 Section1 Auto versions N1058, 1880 vvith dial locked by screvv Section5 Intercom N1636, 37 etc. ETL Cat. 60 Section 4 PAX systems Section1 House exchange N1669, 71, 79 etc. ETL Cat. 49 2+7 PABX 2 +5 Keymaster Secretarial Mk. VI 2 +10 House exchange Section 2 Section5 Section5 Section5 Intercom vvith loudspeaker N1732, 33, 47 etc. ETL Cat. 60 Section 4 PAX systems Section1 Portable (Services type '.J') N1844 ETL Cat. 60 Section1 None Portable N1845 F, .JK etc. N1980, 85 etc. ETL Cat. 60 Section1 None ETL Cat. 60 Section1 None 2 -vvay batteryringing types N1990, 91 etc. ETL Cat. 60 Section4 None Magneto (handgenerator type) N 2124, 2186, 2206, 2516 ETL Cat. 60 Section1 Magneto teles. N 2128, 2208, 2908, vvith transistor generators Section5 ETL Cat. 60 Section1 Plan-Etelphone Systems (Types1 and3 ) 2 +7 PABX 2 +5 Keymaster Secretarial Mk. VI 2 +10 House exchange Section 5 Obsolete Product Telephones: 'Etelux' Plan-Etelphone systems2 and 4 to15 Section5 Section 2 Section5 Section5 Section 5 Svvitchboards: 6 -line magneto type N564 ETL Cat. 60 Section2 12-line magneto svv/bd N569 Section3 50 /70 floorpattern CB svv/bd N 326 series ETL Cat. 60 Section2 100 -line CB svv/bd N 327 Section3 Private automatic branch exchanges: 4 extensions+ 1 exchange line ATE4 .1 .1 7045 2 +5 Keymaster Section5 9 extensions+ 3 exchange lines ATE9 .3 .3 7046 5 +20 PABX equipped3 +10 Section 2 Obsolete Product Code No(s) Old Catalogue Reference Replacement Product This Catalogue Reference 20 extensions+ 5 exchange lines ATE 20.5.5 7047 5 +20 PABX fully equipped Section 2 24/49 extensions +4/10 exchange lines ATE 25/50 7051 10+50 PABX Strowger, or Crossbar PB 100 Section 2 48 extensions + 6 exchange lines ATE 50.6.6 7050 20 +100 Strowger, sub-equipped, or Crossbar PB 100 Section 2 98 extensions + 12 exchange lines ATE 100.12.12 7049 100 extensions and upwards ATE 211 7048 Types 3, ET4 and Crossbar PBT Sheet to be issued ETL Cat. 60 Section 7 Strowger 10 +50, Type 3 and ET4; Crossbar PB 100, PB 480 and PBT Section 2 ETL Cat. 60 Section 9 None ETL Cat. 60 etc. Section 9 Rurax ETL Cat. 60 Section 1 None ETL Cat. 60 Section 3 None Rurax ERP 1, 3 and 4 PABXs Miscellaneous: Line connector 20 +4 type Minirax N 22525B1 Multiphone system N 1643, 44 23989, 90 etc. Speech inverter ESE10 N 34360A1 A2 etc. Time announcer PLESSEY Telecommunications Printed in England Section 4 The Plessey Company Limited, Telecommunications Group, Private Systems Division, (Dept. L.A.), Beeston, Nottingham, NG91 LA. Telephone: Nottingham (0602) 254831. Publication No. 7203 Telex: 37201 '®1ZH202/2k/5.71 /S - PLESSEY TELECOMMUNICATIONS p A x t Private Automatic Exchanges - PRIVATE AUTOMATIC EXCHANGES Designed with emphasis on low cost and simplicity, these newly developed 10- and 15-line private automatic exchanges provide secret communication between extensions, with intrusion facilities available to selected extensions. Both exchanges are ideally suited for use in small manufacturing units, depots, warehouses, offices, small businesses, and similar estab lishments where they can function adequately as the sole means of internal communication. Alterna tively, either can be gainfully employed as an auxiliary system in larger organisations to relieve the internal traffic load on a busy private branch exchange, so en abling the PBX operator to handle the important external calls with greater ease and efficiency. Highlights general to both designs: Powered by integral transformer/ rectifier-types available cover all normal mains voltages and fre quencies. Mains derived ringing and tones eliminating need for expensive conventional equipment. Low fault liability-robust and reliable components. Easy maintenance - straight-for ward circuit design. Wall mounting-small space re quirements. Total enclosure. High-grade finish. SECTION 1 10- and 15-line PAX Units Facilities 10-line PAX This unit, equipped with one connecting circuit, provides secret 15-line unit with cover removed communication between any two of up to 10 extensions at any one time. Calls are made by dialling single-digit codes, the extensions being numbered 1 to 0. One extension may have an in trusion facility enabling the user to intervene in an established connection. This is accomplished by momentary operation of the pressbutton provided on the par ticular telephone, and signalled by an intrusion tone to line. The engaged parties clear down on request, and the wanted extension is then dialled. 15-line PAX Two connecting circuits perrr,it two simultaneous secret con versations between any two pairs from up to 15 extensions. Calls are made by dialling one or two-digit codes, extensions being numbered 1 to 9 and 01 to 06. Up to three extensions may be provided with intrusion facilities. When a dialled extension is En gaged, busy tone is transmitted. If the caller has the intrusion facility, he can break into the engaged connection by dialling digit 1. When the engaged extension users replace their handsets on request, the wanted extension is re-called automatically. Equipment Features The exchange equipments are housed in mat elephant-grey all metal cabinets fitted with quick release covers. The switching apparatus is of British Post Office standard type and consists of strip relays Type 12 (common yoke), major relays Type 3000, and two types of single motion selector; miniature (10-line unit) and heavy-duty type (15-line unit). The apparatus is mounted on a hinged-gate framework, giving convenient access to rear wiring and the backplate miscellaneous equipment. This includes the line terminal block and ringing-and tone equipment, comprising mains transformer (with input, output and d.c. fusing), rectifier, and capacitor/resistor network. The backplate incorporates wall mounting brackets and protected cable entry holes for the passage of line cables and mains supply leads. Connection to the mains supply can be permanent or by flexible lead and plug. Wiring is p.v.c.-insulated throughout. Ringing and Tones Ordering Information Dial, busy and intrusion tones are mains derived via a 28V trans former tapping and capacitor/ resistor network. Ringing is at mains frequency and transformer tapped at 56V (nominal). When ordering, please specify re quired items and corresponding code numbers from the table below. Also state quantities and give: Power 2 Colour phones. The working voltage of both exchange units is 45 to 55V d.c. (50V nominal), derived from the standard built-in transformer which is designed for connection to 50Hz mains supplies within the range of 200 to 250V. Alterna tively, transformers for operation on 60Hz, or within the range of 100 to 150V, can be supplied. Extension Telephones Two-wire Plesseyphones specifi cally developed for PAX working are recommended for general ex tension use. For the extension with the intrusion facility on the 10-line unit, a 3-wire version with pressbutton is available. Both types are supplied in silver-grey, lava green, hemp beige, ivory and black (see catalogue sheet 7159). Alternatively, other types of stand ard automatic telephones with and without pre::;sbutton can be used, provided each incorporates an a.c. ringer and has a dial adjusted to transmit 10 pps with a 2 :1 break/make ratio. Line Limits The loop resistance of extension lines can be up to 1OOn for the 1O line unit; for the 15-line unit 550n maximum is permissible. Using 6�1b/mile (0·5mm) cable, these values correspond respectively to distances between the PAX and telephone of approximately 625yd (593m) and 3585yd (3262m). Dimensions 10-line unit 12in x 8fiin x 7 156in (305 x 221 x 186mm). 15-/ine unit 12in x 24in x Stin (305 x 610 x 209mm). Weights One 10-line unit 141b (6·4kg) net. 4 units (multiple export pack) 1121b (50·8kg). One 15-line unit 481b (21·8:<g) net. 4 units (multiple export pack) 2601b (117·9kg). Details of local mains voltage and frequency. of extension tele- 3 Number (up to 3) of extensions requiring intrusion facilities (15line PAX only); this information determines the strapwiring ad justments to be made in the PAX unit before despatch. Equipment item Code No. 10-line exchange unit N24451A 15-line exchange unit N24608A 2-wire telephone N2020C 3-wire telephone with pressbutton (10-line PAX only) N2021C 10-line unit 10-line unit with cover removed 10-line unit with hinged gate open As a result of continua/ efforts to improve design, equipment supplied may vary from that described or illustrated in this publication. PLESSEY The Plessey Company Limited, Telecommunications Group, Private Systems Division, (Dept. L.A.), Telecommunications Printed in England Beeston, Nottingham NG9 1 LA, England. Telephone: Nottingham (0602) 254831. Publication No. 7157 Telex: 37201 '�ZH1202/21<14.71 /3 PRIVATE AUTOMATIC EXCHANGES Long, reliable service and minimum maintenance are ensured by this PAX which is designed for busi ness houses, hotels, etc. requiring not more than 25 lines. The single unit occupies very little floor space. The stock equipment is 15 line and two connector circuits but equip ment can be supplied to order and extended as required to the capa city of 25 line and four connector circuits, the unit being fully wired to facilitate such extension. Maximum extension line loop re sistance. including the telephone, is soon. SECTION 1 5 Secretarial. For the executive who may not wish to be always directly accessible by telephone. Various schemes available. PAX 25 6 Two-party line. Permits in dividual service to two exten sions over one pair of wires, thus reducing line costs. The two can communicate with each other, and either can make or receive calls without disturbing the other. Numbering and Facilities The numbering scheme is 1 to 9, 01 to 09 and 001 to 007. Full intercommunication by direct dialling, with complete secrecy except on party lines, is given. The following special facilities are provided as ordered, the extra equipment listed in the Table on the back page being wall mounted unless otherwise stated below. Preference ('Automatic' or 'Op tional'). Enables selected exten sions to switch in on engaged lines. No extra apparatus re quired. Automatic Preference is given by means of a strap on the particular line circuit. For Op tional Preference the telephone must have a pressbutton. 2 Tie line. For intercommunica tion between two PAXs. Up to two circuits can be mounted on the unit; others may be wall mounted. Suitable terminating equipment is necessary at the remote PAX, therefore the type of exchange should be specified. Extra equipment is necessary for long lines. Preference extensions can be given access to a busy tie line if required. An extra rectifier per tie line is necessary if the remote PAX is 50V. 3 Loudspeaker with Direct Call. Executive's loudspeaker tele phone equipped with 10 double throw keys for the direct calling of up to 20 selected extensions by a discriminating ringing signal. 4 Conference and Direct Call. Direct Call keys referred to in paragraph 3 can be used to connect together the executive and up to 10 Direct Call exten sions for Conference when the Conference facility is specified. Direct Call facilities need not necessarily include Conference. • I PAX 25 with cover removed 7 Loud-ringing bells. A loud ringing mains signalling bell, such as N3137B, can be opera ted via the contacts of a d.c. relay supplied in a case. 8 Staff call. Any one of up to 15 persons may be called by dialling a code number to operate bells or buzzers throughout the premises. A person thus called dials '8' on the nearest telephone and is auto matically connected to the caller. The equipment can be mounted on the unit unless a battery eliminator is to be accommo dated. Visual code call systems, with or without an audible warning signal, for up to 15 codes can be supplied. Details will be furnished on request. All signalling devices are ordered separately. 9 Discriminating ringing. For use by executives or other selected extensions to indicate when such persons are calling. Equipment PAX Unit This is a grey-enamelled pressed steel dustproof unit of small size which stands on the floor and is supported 3in (76mm) from a wall by two brackets at the top. Drillings for floor fixings if required are in cluded. The front cover is re movable, the rear cover sealed. The system operates on the 'line circuit control' principle. Heavy duty uniselectors (BPO No. 2) are used as linefinders and connec tors. Relays are Type N30000 (BPO 3000). The uniselectors are on a hinged shelf. Line and miscellaneous relays are strip mounted. Jack-in mountings are used for connector and ringing and tone relay sets. The incoming wires are soldered to tags at the top of the unit, then cross-connected by jumpers to screw terminals below. A white painted strip on the top ironwork is used for wire designations. The equipment has full tropical finish. Connecting wires are pvc insulated. Dimensions Equipment Item Height Width Depth in (mm) in (mm) PAX 25 69 (1753) 30;t (768) 914 (235) 3A Battery Eliminator 714 (184) 24k (623) 10k (267) in (mm) Weights Equipment Item Code No. Net Weight lb (kg) Shipment Weight lb PAX 25 N22425AT 223 (101 ·2) 3A Battery Eliminator N22406A 35k (16·1) (kg) Two Crates 411 95 (186-4) (43·0) 72 (32·6) Additional Equipment Type No. N22426T N22427T N22429T N22400AT N22422 N22436T N22438T N22440AT N22440BT N22444T N22446T N22442T N22506C Equipment Remarks One line circuit State whether circuit No. 3 or 4 One connector circuit Set of spares Set of maintenance tools Set cf installation material One tie-line circuit Does not include long line equipment Direct Cal I without Conference Cont. and Direct Call 1-10 Cont. and Direct Call 11-20 Discriminating ringing One two-party line Serves up to 20 Direct Call extns I._ Not more than 10 Direct Call extns f can be connected for Conference One per four Direct Call lines Does not include line circuits Staff call (audible system) 15 persons max. (Visual systems also D.C. relay in case For operating loud-ringing bell supplied) Power Equipment Ordering Information The working voltage is 20 to 26V (24V nominal). With reliable a.c. mains, a 3A battery eliminator N22406A suit able for inputs of 100/125V or 200/250V, 40 to 60Hz and which mounts on the unit may be used. Alternatively, a 1 OAh battery and 1A auto charger can be supplied. If the mains supply is d.c., duplicate 1 OAh batteries and a charging resistor are necessary. When ordering, please specify: Extension Telephones Plesseyphones (catalogue sheet 7159). specifically developed for PAX working are recommended for general use. Alternatively, other types of standard automatic tele phones such as Etelphones (cata logue sheet 7145) can be used. 1 Quantity and codes where ap plicable. 2 Initial and ultimate requirements if these are different from the stock equipment. 3 Special facilities required; also miscellaneous items such as tools, spares, loud-ringing bells, etc. 4 Whether battery and charger, or a battery eliminator are required. 5 Local mains voltage and fre quency. 6 Number and types of telephone instruments required. 7 Dimensions of proposed ap paratus room, including clear height. As a result of continual efforts to improve design, equipment supplied may vary from that described or illustrated in this publication. PLESSEY Telecommunications Printed in England The Plessey Company Limited, Telecommunications Group, Private Systems Division, (Dept. L.A.), Beeston, Nottingham, NG91 LA, England. Telephone: Nottingham (0602) 254831. Publication No. 7115 Telex: 37201 �ZH1137 /2k/4.71 /S e PRIVATE AUTOMATIC EXCHANGES This equipment, similar in many respects to PAX 50/400, is used when not more than 50 lines will ultimately be required. Excepting power equipment, and possibly some items required for special facilities, all apparatus is accom modated in a single unit. The stock unit is equipped for 30 line and four connector circuits, but equipment can be supplied to order and extended as required to the capacity of 50 line and seven con- nectar circuits, the unit being fully wired to facilitate such extension. Maximum extension line loop re sistance, including the telephone, is soon, but long-line equipment to SECTION 1 PAX 50 extend this limit can be supplied. Numbering and Facilities A two-digit numbering scheme is used. Full intercommunication by direct dialling, with complete secrecy, except on party lines, is given. PAX 50 Unit. with front door and some apparatus covers removed The following special facilities are provided as ordered, the extra equipment listed in the Table on the back page being on the unit or wall mounted, depending upon the quantity. 1 Preference ('Automatic' or 'Op tional'). Enables selected exten sions to switch in on engaged lines. A resistor per preference line is required. With Optional Preference, access to an en gaged line is obtained by dialling a code digit on receiving busy tone. 2 Tie line. For intercommunica tion between two PAXs. Up to three circuits can be mounted on the unit; others may be wall mounted. Suitable terminating equipment is necessary at the remote PAX, therefore the type of exchange should be specified. Extra equipment is necessary for long lines. Preference extensions can be given access to a busy tie line and to a busy extension at the remote PAX if required. An extra rectifier per tie line is neces sary if the remote PAX is 50V. 3 Loudspeaker with Direct Call. Executive's loudspeaker tele phone equipped with 10 double throw keys for the direct calling of up to 20 selected extensions by a discriminating ringing signal. 4 Conference and Direct Call. Direct Call keys referred to in paragraph 3 can be used to con nect together the executive and up to 10 Direct Call extensions for conference when the Con ference facility is specified. Direct Call facilities need not necessarily include Conference. 5 Secretarial. For the executive who may not wish to be always directly accessible by telephone. Various schemes available. 6 Two-party line. Permits indivi dual service to two extensions over one pair of wires, thus re ducing line costs. The two can communicate with each other, and either can make or receive calls without disturbing the other. 7 Loud-ringing bells. A loud ringing mains signalling bell, such as N3137B, can be opera ted via the contacts of a d.c. relay supplied in a case. matically connected to the caller. Visual code call systems, with or without an audible warning sig nal, for 7, 15 or 30 codes can be supplied. Details will be fur nished on request. All signalling devices should be ordered separ ately. 9 Discriminating ringing. For use by executives or other selected extensions to indicate when such persons are calling. 10 PBX hunting. Enables a num ber of lines (usually up to four) to be called by dialling the number of the first line. If the first line is engaged, the call is auto matically connected to the sec ond line, and so on. If the direc tory number of the second or third line is dialled the call is not con nected to the next line under engaged conditions. 11 Emergency lines. Where lines are used as reporting points for emergency calls such as fire alarm, ambulance, etc., normal line circuits would be terminated on telephones (usually red) not equipped with a dial, to prevent them being used for outgoing calls. If it is required that these extensions be called by dialling a number outside the normal num bering scheme, then additional equipment is necessary. Power Equipment The working voltage is 20 to 26V (24V nominal). If a reliable a.c. mains supply is available, a battery eliminator, N22406B, may be used. It is de signed for inputs of 100/125V or 200/250V, 40 to 60Hz, has a 5A output, and mounts on a wall. Alternatively, a 20Ah battery and 3A auto charger can be supplied. If the mains supply is d.c., dupli cate 20Ah batteries and a charging resistor are necessary. Orders should specify the type of equipment required and the mains voltage and frequency. Equipment PAX Unit This is a grey-enamelled pressed steel dust-proof unit of small size, totally enclosed by removable doors at the front and rear, the supporting wall brackets at the top being 21 in (533mm) long, to allow access to the rear. Drillings for floor fixings if required are included. The system operates on the 'register control' principle, the dialled im pulses being received by either of Extension Telephones Plesseyphones (catalogue sheet 7159), specifically developed for PAX working are recommended for general use. Alternatively, other types of standard automatic tele phones such as Etelphones (cata logue sheet 7145) can be used. Dimensions Equipment Item in Height (mm) in Width (mm) in Depth (mm) PAX 50 66 (1676) 30� (775) 12� (314) 5A Battery Eliminator 12 (305) 24� (623) 8 (203) Weights 8 Staff call. Any one of up to 15 per sons may be called by dialling a code number to operate bells or buzzers throughout the premises. A person thus called dials '8' on the nearest telephone and is auto- two register circuits which drive the connector switches to the appropriate outlets. The apparatus is arranged as shown in the illustration. All switches are heavy-duty uniselec tors (BPO No. 2). Type N30000 (BPO 3000) relays are used in all except the line circuits, which employ twin relays Type N44700. Three tie-line circuits, or apparatus for other special facilities, can be accommodated in the space near the bottom of the unit. The incoming wires enter through the top of the cabinet and are sol dered to connection strips along side the uniselectors. A distribution box providing cross-connecting facilities for the lines can be sup plied for wall mounting if specified. The equipment has full tropical finish. Connecting wires are pvc insulated. Equipment Item Code No. lb PAX 50 N22450AT 5A Battery Eliminator N22406B Net Weight (kg) 363 46� (164·8) (21 ·1) Additional Equipment Remarks Equipment Type No. N44846TK N22451T N22452T N22400AT N22422 N3592A N22460T N22462T N22464AT N22464BT N22469T N22466T One line circuit One connector circuit Set of spares Set of maintenance tools Set of installation material Resistor for pref. line One tie line circuit Direct Call without Conference Conf. and Direct Call 1-10 Conf. and Direct Call 11-20 One two-party line Staff call (audible system) N22506C D.C. relay in case When ordering, please specify: Quantity and codes where ap plicable. 2 Initial and ultimate requirements if these are different from the stock equipment. 3 Special facilities required; also items such One per preference line Serves up to 20 Direct Call extns L Not more than 10 Direct Call extns f can be connected for Conference Does not include line circuits For a maximum of 15 persons, (visual systems for 7, 15 or 30 codes also supplied) For operating loud-ringing bell tools, spares, loud-ringing bells, etc. Ordering Information miscellaneous State circuit No. (5, 6 or 7) as 4 Whether battery and charger, or a battery eliminator are required. 5 Local mains voltage and fre quency. 6 Number and types of telephone i nstruments required. 7 Dimensions of proposed appara tus room, including clear height. As a result of continual efforts to improve design, equipment supplied may vary from that described or illustrated in this publication. PLESSEY The Plessey Company Limited, Telecommunications Beeston, Nottingham, NG91 LA. Telecommunications Group, Private Systems Division. (Dept. L.A.), Printed in England Telephone: Nottingham (0602) 254831. Publication No. 7116 Telex: 37201 ·�ZH1138;2k/4.71 /S PRIVATE AUTOMATIC EXCHANGES Being of extensible type, this register-controlled PAX is ideal for progressive organizations where expansion from time to time may be anticipated. It employs single motion selectors throughout and may be partially or fully equipped up to a maximum of 400 lines, the minimum number of lines being 50. The exchange equipment is com posed of 50-line units specially designed to facilitate extension, an open-type main distribution frame (accommodating fuses and arres tors, if required) and the power plant. Maximum extension-line loop re sistance, including the telephone, is 1 ooon, but long-line equipment to extend this limit can be supplied. Numbering and Facilities A 3-digit numbering scheme is used. Full intercommunication by direct dialling, with complete secrecy except on party lines, is given. The following special facilities are provided as ordered, the extra equipment listed in the table on page 3 being wall mounted unless otherwise stated below. SECTION 1 Extensible Unit Type 50/400 PAX Preference ('automatic' or 'op tional'). Enables selected exten sions to switch in on engaged lines. One resistor per preference line is required for fitment on the unit. For automatic preference, one PF relay per register is also required. With optional preference, access to PAX 50/400 stock units, with some apparatus covers and the front doors removed. Note cable support on top. an engaged line is obtained by dial ling a further digit. Tie Line. For intercommunication between two PAXs. Suitable ter minating equipment is necessary at the remote PAX, therefore the type of exchange should be specified. Extra equipment is necessary for long lines. Preference extensions can be given access to a busy tie line and to a busy extension at the remote PAX if required. Loudspeaker with Direct Call. Executive's loudspeaker telephone equipped with 10 keys for the direct calling of up to 20 selected extensions by a discriminated ring ing signal. Conference and Direct Call. Direct call keys referred to in the previous paragraph can be used to connect together the executive and up to 10 direct-call extensions for confer ence when the conference facility is specified. Direct-call facilities do not necessarily include conference. Secretarial. For the executive who may not wish to be always directly accessible by telephone. Various schemes available. Two-Party Lines. Permits indivi dual service to two extensions over one pair of wires. The two can communicate with each other, and either can make or receive calls without disturbing the other. Three numbers are allocated per two party line. Loud - Ringing Bells. A loud ringing mains signalling bell, such as N3137B, can be operated via the contacts of a d.c. relay supplied in a case. Staff Call. Selected persons may be called by dialling a code number to operate bells or buzzers throughout the premises. A person thus called dials 8 on the nearest telephone and is automatically connected to the caller. There are various visual schemes for up to 64 codes, or audible schemes, or schemes giving a combination of both audible and visual signals. Details on request. All signalling devices should be ordered separately. Discriminating Ringing. For use by executives or other selected exten sions to indicate when such per sons are calling. PBX Hunting. Enables a number of lines (usually up to 4) to be called by dialling the first line directory number. If the first line is engaged, the call is automatically connected to the second line, and so on. If the directory number of the second or third line is dialled, the call is not connected to the next line under engaged conditions. The equipment has full tropical finish. Connecting wires are p.v.c. insulated. Cables are sheathed in cream p.v.c. Emergency Lines. Where lines are used as reporting points for emer gency calls, such as fire alarm, ambulance, etc., normal line cir cuits wou:d be terminated on tele phones (usually red) not equipped with a dial, to prevent them being used for outgoing calls. If it is required that these extensions be called by dialling a number outside the normal numbering scheme, additional equipment is necessary. Main Distribution Frame This is a single-sided, open-type frame for wall and floor fixing. It is equipped with connection strips and jumper rings to form a cross connecting field for the lines. Should any of the lines require fuses and arrestors, these can be accommodated. Power Equipment The working voltage is 46-54V (50V nominal). Switching Units These are grey enamelled, pressed steel, dustproof units, with re movable front and rear doors. They are self-supporting and drilled for floor fixing. Units may be type 'A' or 'B', equipped to order and are installed in suites in the sequence: A.B.B.A.B.B.A.B. In order to simplify extension, all are fully wired and the maximum number of wire connections are completed in the factory. All switches are heavy-duty (BPO No. 2) uniselectors. Line relays are twin type N44700; other relays are N30000 (BPO 3000) type. Inter-unit cables are run through the sides of the cabinets whilst i.d.f. cables are on supports attached to the top. Both sets of cables are soldered to connection strips. If the number of lines will never exceed 200 and a reliable a.c. mains supply is available, a battery eliminator N22405B, output 1 OA for up to 100 lines, or N22405C, 15A for up to 200 lines, may be used. Both are designed for inputs of 100/125 or 200/250V, 4060Hz, and for wall mounting. A battery and auto charger are recommended for larger equip ments, or in lieu of the eliminator for the smaller installations if preferred. With a d.c. supply, duplicate bat teries and a charging resistance are necessary. Extension Telephones Plesseyphones (Catalogue Sheet 7159), specifically developed for PAX working, are recommended for general use. Alternatively, other types of standard automatic tele phones such as ETELPHONES (Cata logue Sheet 7145) can be used. Stock Units These are equipped as indicated below, and wired to cater for ultimate quantities quoted in brackets. "A' Unit 'B' Unit N22475 *6(7) *6(7) *5(6) 2(2) sets 50(50) *6(7) sets N22476 Group selector switches Linefinder switches Connector switches 3(6) 1 (1) set Register, 'units". 'tens· and "hundreds" switches Line relays, twin type I 25(50) Group selector relays � Strip mounted 4(7) sets Miscellaneous relays 1 (1) set 1 (1) set J Connector relays (upper shelf) 3(5) 5(5) Connector relays (lower shelf) -(1) 1 (1) 2(2) Register relays (lower shelf) Jack-in Tones set (l