Patent GB-730782-A (GB)
Title: Improvements in or relating to circuit arrangements for telecommunication installations comprising relay selectors
Inventor: SPIECKER FRIEDRICH
IPC: H04Q3/00
Filed: 1952-07-30
Abstract: 730,782. Automatic exchange systems. SIEMENS & HALSKE AKT.-GES. July 30, 1952, No. 19321/52. Class 40 (4). In a relay arrangement for connecting an incoming line (e.g. ER4, Fig. 2) to a large group of outgoing lines, the large group is divided into groups TnGr1, TnGr2, ... (of which only TnGr1 is shown in Fig. 2), and intermediate lines lZLe, 2ZLe ... are provided between switching stages, the arrangements are such that group couplers EGK1 . . . having access to the groups are connected in multiple to the preceding intermediate lines 1ZLe and each outgoing line has access to any one of said intermediate lines lZLe. General description, Fig. 2. An incoming link circuit such as ER4 is required to be congroup, e.g. ER1 . . . ER10 having access to any of ten interstage lines, e.g. 1ZLe1 ... 1ZLe10 which are common to the 1000 subscribers, through a 10 x 10 array of relays EVK1. Each interstage line, e.g. 1ZLe1, has access over the coupling relays EGK1 to 4 of 20 interstage lines 2ZLe, which 4 are accessible also from a further interstage line 1ZLe6. Four sets of 20 2ZLe interstage lines are provided, each serving 250 subscribers. The 2ZLe lines serve 5 groups of 10 3ZLe interstage lines, one'3ZLe line having access to 2 2ZLe lines over coupling relays such as EZK1. Each group of 10 3ZLe lines has access to 50 subscribers over coupling relays such as LK1. The incoming digits are received in a register EZE which then seizes a common marking circuit LEF which marks the wanted subscriber's line and co-operates with control circuits 1EO1, 2EO1 and LO1 to seize a free route between the wanted subscriber and the incoming circuit ER4. Detailed description, Figs. 3, 4, 5. The incoming last three digits set relays (not shown) in the register EZE which in turn set a hundreds relay H1 and one of a hundred relays Z12 indicative of the tens group of the wanted line. Contacts of this relay combine with units designating leads ea4 from the register to mark a lead tn21124 indicative of the wanted subscriber. Contacts of the Z relays are grouped to indicate over lead 35 which group of 250 lines contains the wanted subscriber. In the marking circuit relay F in the incoming circuit ER4, relay Ka1 in the wanted subscriber's line circuit and An1 in the control circuit LO1 are operated. Each interstage link is associated with a relay which is operated when the link is busy or becomes operated when a test is initiated to determine whether the link has a free route of access to the incoming circuit ER4. Thus the links 1ZLe1 . . . 1ZLe10 are associated with relays C1 . . . C10 which are operated when the links are busy. Links 2ZLe1 . . . 2ZLe20 are associated with similar relays C5<1> ... C5<20> which however contain second windings (ii) which are energized when no means of access back to ER4 is available. Thus relays C5<1>, C5<2> associated with links 2ZLe1, 2ZLe2 are operated if both relays C1, C6 corresponding to links 1ZLe1 and 1ZLe6 are operated. Relays C5<11>, C5<12> likewise nected to one of a group of a thousand subscribers designated by the last three digits of the wanted subscriber's number. The incoming ER circuits are divided into 5 groups of 10, each block links 2ZLe11, 2ZLe12 if C1 and C6 are both operated. Similar relays CO10 . . . CO1 exist (in that order) for links 3ZLe1 ... SZLe10 which operate over winding (iii) if the links are busy and over winding (ii) if both 2ZLe links to which they have access are busy or blocked. Choice of the 3ZLe link is then effected by the first of a chain of Qe relays which is associated with an unoperated CO relay. When relay F in the incoming circuit ER4 is operated it operates a coupling relay Qer4 associated with ER4 in series with a blocking test initiating relay SpE1<1> associated with the 250 group containing the wanted subscriber. The relay SpE1<1> enables blocking relays C5<1>, C5<2> and C5<11>, C5<12> to be operated in accordance with busy conditions on the preceding links as previously described. Likewise operation of An1 enables CO10, CO5 to be operated in a similar manner. If both links 2ZLe1, 2ZLe2 are free and unblocked first choice is given to 2ZLe1, this being effected by contacts 56c5<1>, 57c5<1> of C5<1> which are included in the fourth (operating) wire of the link, it being arranged that one of these contacts is open whilst the other is closed. Similarly, preference is effected for 1ZLe1 if both 1ZLe1, lZLe6 are free. Assuming that 3ZLel, 2ZLe1 and 1ZLe6 are free and 2ZLe2, and 1ZLe1 are engaged then with Qe10 and C1 up and C5<1> back an operating circuit is completed over the fourth wire for the coupling relays Kz1<1>, Kg6<1>, K6 and relay P in ER4. The coupling relays complete a speech circuit between ER4 and the coupling stage LK1; and Qe10 operates Q10 which brings up Kt1<10> to complete the connection from LK1 to the wanted subscriber. A holding circuit is now completed over the third wire for the coupling relays and link busying relays in series with the subscriber's line and cut-off relays AR1, TR1 and relay P. Response of P initiates release of the marking circuit and the ringing of the called subscriber and supervision of the connection (by means not shown). Modifications. Instead of operating the rela- SpE1<1> over contacts of tens group-designating relays such as Z12, use may be made of a contact of a relay HR1 (Fig. 3a) connected in the operating circuits of all the Z relays corresponding to the 250 line group. Alternatively the SpE1<1> relay may be operated over a lead 97 energized by An1 contacts of all the control circuits LO1 ... 5 associated with the relevant 250 line group. P.B.X. groups. The latter above-mentioned alternative enables a P.B.X. group to contain lines in different 250-line groups of a 1000 line group. The marking wire, Fig. 7 (not shown), is connected to each line circuit over a seriallyrelated chain of contacts of the respective cutoff relays TR1. The marking is thus applied to the first free line circuit of the chain and the response of the appropriate An1 relay determines which of the leads 97 and hence which of the 250-line groups contains the line circuit, and thereby causes the operation of the corresponding SpE1 relay.