DE1276113B - Circuit arrangement for telecommunications, in particular telephone switching systems with multi-stage switching networks - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

H 04m

H 04 q

German class: 21 a3 - 38

Number: 1276 113

File number: P 12 76 113.6-31 (S 93004)

Filing date: September 7, 1964

Opening day: August 29, 1968

The invention relates to a circuit arrangement for telecommunications switching systems, in particular telephone exchanges, with switching matrices, those made up of several coupling stages and interconnected via intermediate lines There are couplers and in which one precedes a connection through-connection Path search process a free path via intermediate lines and couplers for a requested Connection is selected.

Various circuit arrangements of this type are already known.

One of these circuit arrangements is based on the principle that selecting and combining of intermediate lines between the various switching stages for the connection of a Connection via suitable couplers by means of a special network for searching and setting up routes is made, which corresponds to that of the switching network in its routing and superimposed on it as part of it. With the help of switching devices that are looped into this network are, the setting of the crosspoint contacts for a connection path is made. Since these switching means are individually assigned to the coupling points or intermediate lines, they are as to understand coupling fields. Selecting a connection route from several possible connection routes is then done by the marker as the central facility.

A circuit arrangement operating according to the principle described last assumes that at the beginning of the search and selection process a certain input and a certain output of the Switching matrix are designated for which a connection attempt is then made. The designation of the relevant input and output causes a test to be carried out when the connection is attempted possible connections are made between these designated points. at For example, a four-stage switching network are initially marked by marking the input free and therefore available line combinations are sought, which from this input via two Switching stages away to one passing through the intermediate lines of the entire switching network there Lead interface. At the same time, the free available line combinations are shown in the same way searched, which lead from the designated output over two coupling stages to this interface. As a result of this will be those intermediate lines at the interface, circuit arrangement for telecommunications, in particular telephone exchanges with multi-level switching networks

Applicant:

Siemens Aktiengesellschaft, Berlin and Munich, 8000 Munich 2, Witteisbacherplatz 2

Named as inventor:

Dipl.-Ing. Wolfgang Schaefer, 8011 Vaterstetten

which belong to the available combinations are also activated. A part of these intermediate lines is marked from both the output and the input side of the switching matrix. These are the intermediate lines that lie in the course of a connection path between the marked input and output. With the help of a selection process, one of these intermediate lines is found, and then the setting of the crosspoint contacts belonging to this connection path is made with the aid of setting switching means that are looped into the path search and setting network in the course of this connection path.
The said interface thus runs across the from one coupling stage to the next, z. B. from the second to the third coupling stage intermediate line. The search for and combination of intermediate lines takes place on the route search wires at the interface, i.e. at a single point, in that the coincidence of input and output markings is evaluated here. The selection of an intermediate line between the second and third switching stage now determines the aforementioned through-connection path, in that this selected intermediate line also defines the couplers of the second and third switching stage to which this intermediate line leads; Furthermore, the couplers in the first and fourth (last) coupling stage are determined by the specific, designated input and the specific, designated output. And since only one intermediate line runs from each coupler of the first or fourth coupling stage to couplers of the second or third coupling stage, the couplers in the four coupling stages also clearly define the intermediate lines between the first and second or third and fourth coupling stages.

809 598/78

But now it can also happen that in the case described between each coupler the first and second or third and fourth coupling group several intermediate lines run in parallel. Under this condition, you cannot simply choose an intermediate line between the second and the third coupling stage, the entire connection path can be clearly determined because run between the specific couplers of the first and second or third and fourth coupling stage several intermediate lines each, so that there is also a selection under possibly several free intermediate lines must be made.

For this purpose, a very useful circuit arrangement has already been specified, by means of which it is known is, in a simple manner, a through-connection path for a connection via a multi-stage switching network to determine who after a first selection of an intermediate line between two certain Coupling stages, e.g. B. the second and third switching stage, also a selection under intermediate lines between the other coupling stages, e.g. B. the first and second or third and fourth Coupling stage, made possible. This circuit arrangement provides that on one for the desired connection A marker is switched on for the input in question, which has free intermediate lines assigned route search cores of a route search network to outputs of the switching matrix will; furthermore, the transmission of this marking to everyone for the desired connection in question coming exits checked. Then one after the other at the different interfaces (e.g. coupling stages) affects the transfer of the marking on the cut sections of the road; z. B. the route search wires assigned to the intermediate lines are displayed individually one after the other at each interface separated. When one of these path search cores is cut, the marking is transmitted interrupted, it can be seen from this that this section of the route is in the transmission path and accordingly for a through-connection of the desired connection comes into question. This part of the way will then kept in the transferable state, and the route search is then carried out on the next Interface carried out in the same way until a clear connection path for through-connection is fixed over the entire switching network.

The described principle of this circuit arrangement requires a relatively high expenditure of time, since all route searches at the various interfaces must run one after the other and since every path search process at each of the interfaces requires one with regard to the various paths step-by-step testing, i.e. one after the other, is necessary.

The object of the invention is, provided that a plurality of intermediate lines run in parallel from one coupler to one coupler each of an adjacent coupling stage, to avoid the disadvantages of the known circuit arrangements explained in the previous paragraph. This object is achieved in that, in a first selection process, the state of the entire switching network (intermediate lines free or occupied) depending on the route search is, all for a connection across the matrix from one of its inputs to one of its outputs necessary coupler (one in each of the coupling stages) by selecting a single intermediate line or a coupler can be determined in a single coupling stage that between each of the two certain couplers of two adjacent coupling stages several parallel running Intermediate lines are combined into a group of intermediate lines and that in independent from each other and simultaneously running second selection processes per group each one free Intermediate management of the respective group depending on the status (whether free or occupied) of everyone their intermediate lines is selected.

The invention thus enables the establishment of connections via switching matrices for those Much simplified cases in which several intermediate lines are required for a through-connection between couplers two coupling stages in

so come question and where to use everyone of the intermediate lines is dependent on a route search that relates to the entire switching network.

This simplification is firstly that the

Route search referring to the status of all intermediate lines and couplers of the switching matrix only the first selection process, i.e. H. the selection of all to be used for the required connection Coupler, and that this first selection process on the basis of a suitable for this purpose Grouping to be carried out only on a single interface with the same coupling level through the route search network is. This selection can be based on couplers of a second, third ... or penultimate coupling stage or refer to intermediate lines between two adjacent switching stages. The said Second, and crucially, simplification is that the second selections each time only to the intermediate lines running in parallel between two couplers of adjacent coupling stages extend. These second selection processes do not have to process the result of the route search, rather, they each only represent a selection of any free option under possibly several free intermediate lines. These second selection processes are completely independent of one another, so that they can run at the same time. According to a further embodiment of the invention, these are second selection processes with the switching process, i.e. the marking and switching of the The connection path is functionally combined via the switching matrix.

For this purpose there are contacts from link relays that are individually assigned to the link lines and which indicate the status of the intermediate lines (whether free or busy) in a known manner, per Group of intermediate lines interconnected to form a known selection contact chain, whose respective position denotes one of the free intermediate lines. The further measure that with the contacts of the selection contact chain individually indicating the free state of the intermediate lines Windings of the intermediate lines also interconnected individually assigned intermediate line auxiliary relays and that contacts of these are individually assigned to the intermediate lines Response circuits for coupling relays are connected in the couplers, it is now possible to use Using the selection contact chain, mark and

Switching through according to the selection given by the position of the selection contact chain carry out. As a result, time can be saved in an advantageous manner, because the second selection processes fall in time and even functionally with the marking and switching of the connections together.

According to a further embodiment of the invention, the selection contact chain of contacts is the link relay switched ineffective by response of an intermediate line auxiliary relay, so that during a marking and switching process, i.e. when a link relay is also energized the change in the state of the selection contact chain does not affect the intermediate line auxiliary relays can come.

F i g. 1 to 6 and 8 show an embodiment of the invention, but by no means on which the same is restricted;

Fig. 7 shows an application for such a case Embodiment the plan of a small part of a larger telephone network.

In Fig. 7 shows the plan of a telephone network with a star-shaped basic concept and a superimposed mesh network. And located in a star-center center O is connected via a star network with additional centers B and C. Telephone exchanges are located at the points mentioned. The lines connecting them each represent trunk groups. Furthermore, a location X is shown where there is also a telephone exchange. The systems located at Ortend, B and C , in future only designated as control centers A, B and C , can be reached from the system located at location X , in future designated as control center X , via a total of three trunk groups BdI, BdI, Bd7> . From the location of the control center Z, the control center A can be reached via the trunk groups Bd 1 and Bd3 in such a way that lines of the trunk group Bd 3 are occupied only when all the lines in the trunk group BdI are busy, via the detour connections via which in this case was used as a transit office Central C and via which this can be established directly with the central A connecting trunk groups.

In the same way, the control centers B and C can now also be reached from the control center X via lines of a direct line bundle Bd 2 or Bd3. If the trunk group BdI is busy, the control center B can also be reached via the trunk group BdI in a detour via the control center A. If the trunk group Bd 3 is busy, the control center C can also be reached from the control center X via the trunk group BdI in a detour via the control center ^.

From the above it can be seen that for the control of the control centers B and C from the control center X, the trunk groups BdI, BdI and Bd 3 are in a certain order of precedence which determines the overflow when all the lines in a trunk group are busy. The term "overflow" for switching technology is generally known in the specialist literature. The order of precedence of the trunk groups with regard to headquarters B is: BdI, BdI. The order of priority of the trunk groups is with regard to the control center C: Bd3, BdI. The centers ^ and C will be referred to as target points 1 and 2 in the future.

The lines of the line bundle BdI, Bd2 and Bd 3 are connected to the outputs of the switching network KF shown in FIG. The in F i g. 1 in an overview and in FIGS. The switching system shown in detail in FIGS. 2 to 6 and 8 takes into account, among other things, the order of precedence in which the trunk groups are controlled, as explained above and determined by the respective destination point.

In Fig. 1 shows that per se known counting pulse generators Zig are provided, which are required in large numbers for a connection. If a counting pulse generator is initially assigned as an incoming, so

ίο a free memory Sp via a search selector SwI is switched on to receive the dialing information. After the election information has been recorded, a corrector Um is requested. One or more correctors Um can be provided.

One each is available in common for several memories, and each is connected to a central marker Zm . The corrector Um receives the selection information from the memory Sp and determines the information about the tariff, which it receives in a known manner

ao transmits back to the counting pulse generator, and the setting information which it transmits to the central marker Zm.

The switching network is built up in four switching stages, each with single-stage relay couplers (Kill to K4n6 in Fig. 2). The grouping shown in Fig. 2 shows that the couplers of the first and second coupling stage on the one hand and the third and fourth coupling stage on the other hand are combined in groups. Only within such a coupling group are all couplers of the third (or first) coupling stage connected to one another by intermediate lines with all couplers of the fourth (or second) coupling stage. As FIG. 1 shows, each coupling group comprising the third and fourth coupling stage - also referred to as an output coupling group (AKG1 to AKGn) - is assigned a setting set (ES1 to ESn) .

On the basis of the setting information received from the corrector, the central marker Zm causes all those setting sets to be connected to it, to whose assigned output coupling groups lines are connected which are in each case suitable for a required connection establishment. The central marker first determines in which bundles of all of the aforementioned lines at least one line is free which can also be reached at the same time from the occupied counting pulse generator Zig via the switching network KF . For this purpose, route search potential is given by the corrector via the relevant counting pulse generator to a route search network of the switching network KF . Line bundles in which at least one outgoing free line that can be reached via the switching network KF is determined, are available for establishing the connection. The central marker then selects from the activated setting sets the one (e.g. ES1) to whose assigned output coupling group (e.g. AKG1) the first available bundle is connected according to the previously explained order of preference determined by the target point. At the same time, the last-mentioned bundle is determined by the central marker Zm in the one output coupling group. A free accessible line (line) is then selected from this in the setting set. Then a path in the switching network KF for switching the connection through this line is selected and the connection is switched through. Thereupon all central links of the search dial switch themselves

also a response wire and a holding wire for the coupling relay and a path search wire.

In Fig. 3 of all coupling stages KA to KD and of all intermediate line fields each have a coupling

5 point or one intermediate line each is shown. In Fig. 3 on the left, "Zig" indicates that the connections to the couplers of the first coupling stage KA are individually connected to the Zig counting pulse generator. In Fi g. 3 above is for one

o umpteen, through the switching network traversing path a signal wire, z. B. speech artery shown. As an indication that two speech wires are provided, the coupling contacts are labeled α 1/2, bl / 2, elf2 and dl / 2 . The multiple characters next to the coupling con-

SwI up to the setting set, e.g. B. ESl, again and return to their rest position.

The search selectors SwI and Sw2 shown symbolically as rotary selectors can also be used as couplers, ζ. Β. Relay couplers, which are known to have a significantly shorter switching time.

Using the description of FIG. 7 (see above) is now the mode of action of the in the F i g. 2 to 6 described in more detail switching elements shown.

FIG. 2 shows the grouping of the switching matrix, which has already been taken from FIG. 1 is hinted at. The switching matrix, in Fig. 1 with
Designated KF , has single-stage coupler kill up
K4η6 on. These are in a first and second 15 clocks indicate that each input and output switching stage on the one hand and in a third and fourth of the switching network or each intermediate line in the switching stage on the other hand in coupling groups leads to more than one coupling point in a known manner . The couplers thus form £ 111 to below the signal wire is shown in FIG. 3 shown as traversed- £ 110 and £ 211 to £ 210 with the intermediate circuit of a holding wire. This contains the couplers, not shown, a coupling group. The same applies to the couplers £ 311, coupling relays and a £ 310, £ 411, £ 410 etc. within each coupling relay's own holding contact. In the intermediate line group are all couplers of one coupling stage with fields are windings of intermediate line relays all couplers of the other coupling stage over at least Ll, L 211, L 3, each of the state of their at least one, possibly also several - i.e. 25 intermediate lines (whether free or occupied) by their parallel from a single coupler to each one excitation state (addressed or de-energized) only other coupler - intermediate mark. The lines are connected to one another in the intermediate line field Z 2. The intermediate holding wires run on one side over the winding of the intermediate lines from one coupling stage to the other line relay connected to earth potential. The Weiren (KA, KB, KC, KD) through intermediate line panels 30 terführende branch of the holding core is 3. on the Kon-ZI, Z2, Z This can also marshalling clock-L 211 of the link relay L 211 Erdenthalten at which the intermediate line wiring
can be changed in detail; however, that remains
Division into coupling groups exist.

The couplers of the second and third coupling stage 35
are via intermediate lines in the intermediate line field
Z 2 interconnected in such a way that the coupler
all input coupling groups (first and second coupling stage KA, KB) to the couplers of all output coupling groups (AKGl to AKGn in Fig. 1; third 40 can be brought about. Output side leads each and fourth coupling stage £ C, KD) are connected. The number of input coupling groups and the number of outgoing lines connected to them, individual output coupling groups is similar to η connected holding relay H, via which the triggering is given; however, it can also be of different sizes. a connection can be forwarded. If the output coupling groups contain a single line in the third 45 via several outputs from the coupling stage, ten couplers with six outputs coupling network can be reached, each output is assigned one to the fourth coupling stage and six coupling holding relays Ή in this.

ler with ten inputs from the third coupling stage. Below the holding header is shown in FIG. 3 shows a response - each coupler of the fourth coupling stage contains ten wires. This contains the outputs from the coupling network in each coupling point, so that an output 50 with a rectifier G / 1, G / 2, G / 3, G / 4 in output coupling group each has sixty of these outputs connected in series (II ) of the coupling point. These numbers are not essential relays at this crosspoint. The coupling relays are meaningful and only serve to describe what is shown in FIG. 3 only denoted by A, B, C and D , management example. So z. B. due to transport The rectifier G / L G / 2, G / 3, G / 4 are in theoretical considerations, the number of inputs 55 of the switching stages KA and KB another Durchlaßeines coupler of the fourth coupling stage is greater overall direction than in the coupling stages £ C and KD . be chosen as the number of its outputs, whereby this is of essential importance, because this measure would take the accessibility of the outputs of a switching network enables the couplers of the switching stages to be increased. KA and KD or KB and £ C are structurally identical - The couplers are designed as relay couplers and have to be built 60; because firstly, the relays within the have in a known way each grouped according to its coupler in relay strips, which also have inputs and outputs formed with the response windings AU, BII, C Π, D Π cross field; Each input line forms a coupling point with each output line of the coupler for the known purpose of decoupling, the response circuits connected in series to which a coupling relay is connected, via whose contacts 65 rectifiers include GrI, Gr2, Gr 3, Gr4; Two of the relevant input with the relevant Austen, the couplers are usually interconnected with unequal gear. Each intermediate line contains numbers of inputs and outputs each contains a few signal wires, e.g. B. speech lines, the number of inputs as well

potential switchable. The holding wire is galvanically separated here and only functionally connected by the link relay L 211.

Like the speech artery, the holding wire has the multiple characters, which have the same meaning here have like in the speech artery. On the input side, the holding wire leads via switching means into a counting pulse generator, about the z. B. the release of a connection

of the outputs of a coupler of the first (or second) coupling stage is equal to the number of both outputs as well as the inputs of a coupler of the fourth (or third) coupling stage.

If the couplers of the first and fourth or of the second and third coupling stage are constructed in a structurally uniform manner, the rectifiers consequently have a different polarity in the first two coupling stages than in the third and fourth coupling stage. Depending on this, the excitation of the coupling relays in the first two coupling stages has a different polarity than in the last two coupling stages. With regard to the response wire, this now requires that a connection to be switched through is marked on the response wires at the point in the coupling network at which the coupling stages meet with opposite polarities of the excitation of the coupling relays. This marking is, as will be described in more detail below, with the help of the intermediate line auxiliary relays, e.g. B. Lh, applied to the respective contact point. - The two polarities of the excitation of the coupling relays in the first two coupling stages on the one hand and the third and fourth coupling stage on the other hand require with regard to the holding wire, in which the holding coils of the coupling relays of a connection are basically to be connected in series, that the holding windings are also in the first two coupling stages are excited with a different polarity than in the last two coupling stages. This requirement is met by the measure that the holding wire of an intermediate line, which originates from an output of a coupler of the second coupling stage, is connected to ground potential via the winding of the intermediate line relay and that the holding wire of the same intermediate line, which comes from an input of a coupler of a third coupling stage proceeds, can also be connected to ground potential via a normally open contact of the same intermediate line relay. The holding wires can consequently be connected to negative potential at the other ends. You run, apart from a single link field, through several coupling stages, so that the holding windings of several, z. B. two coupling relays in several, z. B. two coupling stages are in series in a single holding circuit of a connected connection.

The response windings are provided for known reasons for decoupling the response circuits when a single response circuit is marked, so that this marking is always limited to the response circuit of a clearly defined switching path through the coupling field KF .

On the input side , the response wire leads via the counting pulse generator Zig, the search selector SwI, the memory Sp and the search selector Sw 2 into the corrector, in which negative potential can be connected to it in order to switch the connection through. On the output side, the response wire leads to the setting set (ES) that is assigned to the relevant output coupling group. The response artery also has the multiple characters at the crosspoints.

In Fig. 3, a route search artery of the route search network is shown at the bottom. The route search network is a structural image of the entire switching matrix. The Wegesuchader each intermediate line contains a normally closed contact, z. B. 11, the intermediate line relay associated with this intermediate line, for example Ll, which indicates the state of the intermediate line (whether free or occupied) in the path search vein of the intermediate line (contact disconnected or closed). The route search cores of intermediate lines, each leading to one and the same coupler, converge in a route search node corresponding to this coupler (WKlU, for example, corresponding to the coupler KlU, also WK211, WK311, WKAIl) .

ίο Since the in a coupler, z. B. KlU, connecting intermediate lines in this do not lead via switching means (e.g. holding windings, response windings) from as many crosspoints as is determined by the product of the incoming and outgoing intermediate lines, the multiple characters are drawn the other way around than in the holding wire and response wire; because ever an intermediate line leads to several crosspoints of a coupler, whereas all intermediate lines leading to a coupler in a single path search node corresponding to this coupler, z. B. WKlIl, merge.

In the intermediate line field Z 2, the path search vein contains, in addition to the normally closed contact IZ 211 of the intermediate line relay L211, an intermediate line auxiliary relay assigned individually to each intermediate line relay, e.g. B. Lh. Since the route search network is used to mark a route to be switched through in the switching matrix, as will be explained in more detail later, the relay LH serves to record this marker of the route search vein in the intermediate line field Zl and transfer it to the contact artery through contact 21 ή.
The route search wires lead on the input side via a counting pulse generator Zig, a search selector Sw 1, a memory Sp and a search selector Sw2 to the corrector, from which a route search is initiated by closing a contact by the route search potential via the input of the coupling network corresponding to this counting pulse generator Zig the routing network of the switching matrix is carried out. The path search potential spreads from the input to which it is switched on by the corrector, via the path search cores of the intermediate lines to the path search nodes of the fourth coupling stage, provided that the corresponding intermediate lines between all coupling stages are free, that is, the intermediate line relays are de-energized so that their Normally closed contacts in the path search wires of the intermediate lines are closed.

The in the route search node, z. B. WK 411, converging route search cores do not lead to all individual outputs of the switching matrix, but are connected together, ie per route search node, with the setting set corresponding to the respective coupling group. That is why there is also between the route search node WKAH. and the setting set ES no multiple characters are provided.
In addition, all path search cores of the links of the link field Z 3 are individually in the respective output coupling group, z. B. AKGl, corresponding adjustment set, eg ESl, out. As will be explained later, this measure is used to carry out route selection and route marking (through-connection by means of LH relay) in the entire switching network with the aid of the setting kit.

In the event that between the same two

Coupling two adjacent coupling stages more than

809 598/78

an intermediate line runs, so that several Intermediate lines run in parallel, which usually occurs when a switching network is partially expanded, becomes one second route selection among these each running parallel Intermediate lines with the aid of the intermediate line relays L ... and the intermediate line auxiliary relays LH carried out. This second, subsequent route search is explained in detail below.

In Fig. 4 shows further details of a single output coupling group AKG . The coupling relays Cl to ClOO ₃ of which only the first and the last of a first and last row are shown (which also applies to the coupling relays C 801 to C900, Dl to D100 and D 601 to D700) represent a first coupler of the coupling stage KC represents; the coupling relays C 801 to C 900 represent the last coupler of the coupling stage KC of this output coupler. The coupling relays D 1 to D100 and D 601 to D 700 represent the first and last couplers of the coupling stage KD in this output coupling group The response circuits of the coupling relays and the windings correspond to windings C (Π) and D (II) in FIG. 3. Here, too, is as in FIG. 2 and 3 show the link field Z3. The designation KC for the third coupling stage also corresponds to the designation in FIG. 3. The fourth coupling stage KD is already shown here together with parts of the setting set ES, so that the designation KDIES was chosen for it.

The coupling relays of a coupler are connected via row leads and column leads with which the response relay windings, e.g. B. Cl to ClOO, or the rectifier individually connected in series with them, z. B. Gel to GeIOO, are connected, individually excited in a known manner. As is known, the holding windings of the coupling relays, not shown in FIG. 4, and the signal circuits are constructed in the same way in terms of coordinates.

Furthermore, in FIG. 4 shows part of the route search nodes WK311 to WK310 and WK4U to WK 410 with the corresponding route search cores. These route search nodes, in particular the route search nodes WK311 and WK 310, clearly show the previously described summary of the route search cores of all intermediate lines connected to a coupler in one point.

If the corrector applies path search potential via a counting pulse generator Zig to an input of the switching network, it is transmitted in accordance with the procedure shown in FIG. 2 grouping from coupling stage to coupling stage shown, also valid for the route search network, spreads further to all those route search nodes to which intermediate lines closed via intermediate line relay break contacts lead over all coupling stages and link fields. A path search relay is connected to each path search node WK 411 to WK 416 of the fourth coupling stage - and likewise to all path search nodes in the other output switching matrices - which responds when path search potential appears at its path search node. The route search relays are so highly resistive that intermediate line auxiliary relays LH (see. Fig. 3) cannot respond when the route is searched. If a routing test relay of a coupler responds, it says that the outputs of the coupler are accessible, ie that a connection can be switched through if necessary from the occupied counting pulse generator Zig via the switching matrix and via an output of this coupler. The selection of a single one of several route search cores combined in a route search node by the relays N1 to IVIO of the central marker ZM is described below in the description of FIG. 5 and 6 explained.

In FIG. 5 shows further details of an adjustment set provided for each output coupling group (cf. FIG. 2: ES per AKG ... ).

ίο At the ten outputs of each of the six coupler an output coupler array are connected ten outgoing lines, the test and availability wires (c-wire) are individually connected to the test points Ltgl, Ltgl to LtglO respectively. The ten outputs of a coupler always correspond to one in FIG. 5 horizontally shown row of ten test points, e.g. B. Ltgl, Ltgl ... LtglO. The series of ten test points Ltg 51, Ltg 52 to Ltg 60 is also shown, which corresponds to the outgoing lines connected to the sixth coupler of this coupling group.

For each coupler of the fourth coupling stage, ζ. Β, £ 411, is a path test relay, e.g. B. WPl, provided, the winding in F i g. 4 is shown and also in the description of FIG. 4 is mentioned. Working contacts of a path test relay, e.g. JFPl, are to be connected to the test points, e.g. B. Ltgl to Ltg 10, the outputs of a coupler, z. B. the first coupler of this output coupling group turned on. So if path search potential reaches through the path search network of the switching matrix to the path search node of a coupler, so that its path search relay responds, this means that, with regard to the state (free or occupied) of all parts of the switching matrix, a connection from the occupied counting pulse generator Zig to this coupler is possible. By addressing the Wegesuchprüfrais, z. B. WPl, of a coupler, all of its outputs for preliminary testing and line testing are connected through the contacts, e.g.lwpl to 10vv.pl, preparatory to preliminary test bridges VBl to FBlO, which can also be subdivided, such as the preliminary test bridges VB 2 and VBlO in VB 2 α and VB 2 b or VB 10 α and VBlOb, if the lines corresponding to the test points belong to different line bundles. They can also be divided twice. In different setting sets, for example in setting sets ESl and ESn, this subdivision is usually different; however, for the sake of simplicity, it is assumed that the subdivision of the preliminary test bridges is the same in these two setting sets. The rectifiers GrI to Gr 60 are used for decoupling in a known manner. Each complete or subdivided preliminary test bridge corresponds to a marker relay Ml to MIO, through whose contacts, e.g. B. ImI up to 6 ml, the six test points corresponding to a preliminary test bridge, e.g. B. Ltgl to LtgSl, to the six test relays Pl to P 6 after closing the contacts lpk to 6pk of a test control relay PK can be connected.

The test relays Pl to P 6 are mutually dependent in a known manner in a selection dependency by connecting their windings to a changeover switch contact chain formed from their own contacts IpI, 2pl to Ip6, 2p 6.

The setting set also has a connection relay An with contacts lan, 2an to man . The setting kit with its pre-test bridges VB 1 to VB 10 is passed through pre-test via these connection contacts

vpl to vpm can be connected to the pre-test wheels of the same name in the central marker Zm . For this purpose, the connection relay An can be energized by the central marker.

In Fig. 6 the central marker (Zm in FIG. 1) is shown in extracts. In the parts shown, it consists essentially of a number of target point relays, of which the two target point relays ZPl and ZP 2 are shown, and also of five preliminary test relays Vl, Vl .. .VZ, of which the aforementioned are shown, furthermore from a coordinate-shaped rectifier matrix G1 to G 30, from four jumper wirings RV1, RV2, RV3, RVA and a check circuit Ph, which is used for the exact control of the testing of lines selected as free (checking of test lines with regard to triggering connections, if necessary via cables; protection against Double connections). The Zentralmarkierer receives from the corrector To the destination point information using the destination relay ZP1, ZP 2, and so a target point relay is provided for each destination point. Since there are usually several options (different routes, detours via different trunk groups) for reaching each destination point, the central marker, as will be described below, makes a selection from these options. The central marker is connected in parallel to all setting sets ES1 to ESn via a ring line RL.

To help you understand how the central marker works and what it means of its components, two cases of interconnection are combined below with the circuitry connections described, with the exception of the F i g. 6 referred to applies to all other figures and to the preceding parts of the description.

Initially, on the basis of FIG. 7 explains that, for example, from a control center X , the control centers B and C can be reached via the following trunk groups and in the following order of priority of the selection of the trunk groups: the control center B, in the future referred to as destination 1, via the trunk groups Bd2, BdI; and the center C, in the future referred to as destination 2, via the trunk group Bd 3, Bd 1. If a connection from the center X is to be established from a counting pulse generator Zig that is occupied in it to the destination 1 or 2, then in the center X from Corrector around the target point relay ZPl or ZP 2 in the central marker Zm to respond. Furthermore, the contact cb (FIG. 6) of an occupancy relay (not shown) is closed in the central marker.

Now that the central marker has a target point information by z. B. the target point relay ZPl is connected, all trunk groups that come into question to reach this target point are to be checked to see whether they contain at least one free line that can be reached at the same time from the occupied counter Zig via the switching matrix .

The lines connected to the outputs of the couplers of the output coupling groups, combined in line bundles, are always connected to different couplers, and indeed the lines of a line bundle can only be connected to the couplers of a single output coupling group as well as to those of several different output coupling groups. It is now assumed that the lines of the trunk group BdI are only connected to outputs of couplers of the output coupling group A KG and that the lines of the trunk groups Bd2 and Bd3 are each connected to the outputs of couplers of the two coupling groups AKGl and AKGn .

Since the trunk groups Bd2 and BdI come into question to control the target point ZPl, the two corresponding setting sets ES1 and ESn must be connected to the central marker in this case. Apart from the individual wiring of the preliminary test wires vp 1 to vpm with the preliminary test bridges VB ... , These setting sets are of the same type as in FIG. 5 shown. For the purpose of simplifying this description, it should also be assumed that the subdivision of the preliminary test bridges in the two setting sets, which is selected individually in each setting set, is carried out in the same way.

At this point, a few things must be said about the connection of the lines of the at hand F i g. 7 explained line bundle BdI, Bd2, Bd3 are inserted explanatory. It is assumed that the lines of the line bundle BdI are each connected in the output coupling group AKGn to the first outputs of all six couplers K4η 1 to K4n6 , that is, the six test points Ltgl to LtgSl, e . correspond to the preliminary test bridge VBl in the setting set ESn. The bundle Bd 1 thus comprises six lines. It is also assumed that the lines of the line bundle Bd2 are connected in the output coupling group AKG1 to the first outputs of all six couplers and to the second outputs of the first three couplers, that is, the nine test points Ligl to LtgSl and Ltgl to Ltg22, i.e. H. correspond to the preliminary test bridges VB1 and VB2 in the setting set ES1. The bundle Bd 2 thus comprises nine lines. It is also assumed that the lines of the line bundle Bd 3 are on the one hand in the output coupling group AKGl at the second outputs of the fourth, fifth and sixth coupler, which correspond to the test points Ltg 32, Ltg 42, Ltg 52, ie the preliminary test bridge VB2b in the setting set ESl , and on the other hand to the last (tenth) outputs of the first four couplers, which correspond to the test points LiglO to Ltg 40, ie the preliminary test bridge VBlOa in the setting set ESn. The line bundle Bd3 thus comprises seven lines.

If the ZielpuriktrelaisZPl responds in the central marker, this initially means that the setting sets ESl and ESn of the output coupling groups AKGl and AKGn must switch on with their relays An via the ring line RL to the central marker. The mentioned relays An address via the contacts 16zpl to 20zpl in the following circuits:

, ANl (see Fig. 5 as £ 51): AN, An, -.

1. (Fig. 6): Earth, cb, 3vl, 3v2 ... 3 ν 5,

2. (Fig. 6): Earth, cb, 3vl, 3v2 ... 3v5, GIrS, 20zpl, ANn (further Fig. 5 as ESn): AN, An, -.

Both circuits refer to Figures 6 and 5; the latter also represents the setting set ESl and ESn in order to be able to make this description easier.

The wiring R Vl thus defines which setting sets must be connected to the central marker at each of the different target points. This depends on which output coupling groups AKGl to AKGn in total

brought, which should extend to the mentioned preliminary test bridges in the following order: KBl, VB 2 α (both in setting set ESl), VBlOa (in setting set ESn).

It should be remembered that the subdivision of the preliminary test bridges, which are usually in the different setting sets depending on the affiliation of the connected lines different trunk groups,

including those that are suitable for the control of a target point in the setting sets ES 1 and ESn as equally approximated lines. The selection of one is made so that, in the description, a single one of the several initially displayed representation for the two setting sets ES1 and the set setting sets can be used in more detail below. The wiring of the wrote. Preliminary tests vpl to vpm with the preliminary test bridges

The response of the target point relay ZPL means 15, however, are different in both Einstellsätzen, further, that the cables of the cable bundle BdI In Figure 5, the wirings in the two and BdI mentioned in this rank order for a Einstellsätzen shown connects different. The manure production come into question. These bundles wiring in adjustment set ESI are underlined punk comply advantage the Vorprüfbrücken the adjustment set ESI and the dashed lines in the adjustment set ESn dar-KBL and VB 2 and asked the Vorprüf- 20 in the adjustment set ESn.

bridge KBl. Now, under the lines corresponding to these pre-test bridges, the pre-test bridges KBl and VB 2 α in the setting bridges, that is, inside the set ES1 , one wire each with the preliminary test wheels vp 2 and vp (m-l) is shown over dash-dotted lines outside the bundle of lines per preliminary test bridge Form a group to make a selection. This from the ring line RL connected. The preliminary test bridge selection takes place in two steps. First, in 25 KBl in the setting set ESn is connected via a dashed line to a group test process under the pre-test bridge with the pre-test wire bridge one of them through the central marker of the ring line RL . The selection is selected from whose corresponding lines the pre-test bridges is with the pre-test relay Kl, at least one free and at the same time accessible; er V2 to VS made. These pre-test relays can be reached when, as described above, 30 high-resistance and can preferably be designed as an electronic coupler to which they are connected, accessible electronic assemblies. You check if the assigned contact, e.g. lwpl, is closed under the one corresponding to a preliminary test bridge. To understand how the reach lines at least one is free and reachable. Since only the preliminary test relays Kl, V2 and V5 are shown, it should be added here that they are at the same time as 35, these are used in the description for the output of the destination information route search selection. The windings of the pre-test potential across the relays Kl, V 2 to VS, which are assigned the corrector Um , are connected to one of the Kon counting pulse generators Zig at the relevant input clocks 11 zpl, 12zpl to 15zpl / Uzp2, 12zp2 until the coupling field KF is switched on and that such as 15 zp 2 etc. connected to the target point relay. If this is described above, depending on the state 40 target point relay lzp addressed, then the preliminary (whether free or occupied) of all parts of the coupling network test relay Kl via contact 11 zpl, which address the preliminary test path search relay, e.g. the path search wire vp2 and the contact 2an in the setting set ESl test relay WPl via the following circuit: with the pre-test bridge VB1 of the setting set ESl

tied together; Furthermore, the pre-test relay V 2 is via the

3. - (Corrector), ..., (Zig) (further Fig. 3): 45 contact 12zpl the Vorprüfadervp (m-1) and the ^v " ^v ' ^{v 5} ' contact {m - \) an in the setting set ESl with the vor

test bridge VB2a of the setting set ES1 connected; Furthermore, the pre-test relay VS is connected via the contact 15 zpl, the pre- test wire vpm and the contact man 50 in the setting set ES η to the pre-test bridge KBl in the setting set ESn .

The preliminary test bridges are connected to the outputs of such couplers with test leads Lines via contacts of the couplers

WKUl, GlH, 11, WK211, G112, 1/211, LH, WK3U, OwSWl, / 311/1, Gw411 / 1 (further Fig. 4): WKAIl, WPl, earth.

Other route test relays also respond, which also have route search potential. The route search relay now mark with their con

clock, eg lwpl, whether the relevant lines 55 associated path search relay are connected and can be reached. to which a connection in the switching matrix of the

When selecting the pre-test bridges, the assigned counting pulse generator is possible.

The preliminary test bridges therefore only carry free potential from test lines that are free and at the same time

The order of precedence relating to the trunk group must be observed. This test must therefore be the pre

test bridges KBl and KB 2 can be reached in the setting set ESL 60. The aforementioned pre-test relays respond to the pre- test bridge VB10a of the setting, provided that at least one line is free and accessible at the same time on the pre-test bridges of the setting sets connected to them.

It is now assumed that the test points line 2 in

prefer the set ESn .

Since the second step of the test - the individual line test - can only ever apply to the lines corresponding to a single pre-test bridge, the setting set ESl and Ltgl and LtgSl can be adjusted when selecting a pre- test set ES η lead to free potential, so that the pre-test bridge address a sequence of precedence for the action circuit, which extends to all preliminary test bridges, relays K2 and VS in the following branched current end:

4. Earth, co, 3ν 1,3v2 ... 3v5,

Gr 2, 2 wp I ₅ Ltg 2, ...-

GIr 2, V2, 12 zp I ₅ vp (m - 1), (m - 1) an (ES 1), VB 2 a,

GIr5, V5, 15z /? I ₅ vpm, man (ESn), VBl,

Gr 1, 1 wp 1, Gr 51, lwp6, Ltg51, ... -

The responsive pre-test relay separates circuit 1 at contact 3 ν 2 and forms the following holding circuit for its own winding:

5. Earth, ab, 3 vl, 2v2,

-1) (m-1) to (inESl): VB2 <, Gr2,

zpl, AnI (m ESl): AN, An

By disconnecting the contact 3 ν 2, the pre-test relay VS is de-energized, as may the other pre-test relays not shown (between V2 and VS). ao

By responding to a pre-test relay, a single pre-test bridge in one of the possibly several switched-on setting sets selected, at least one with both free as well as reachable outgoing line. Since a preliminary test bridge is only ever one Setting set can also belong to one of the possibly several switched on is also second Setting sets selected.

This is described in more detail below: As shown in FIGS. 5 and 6, when contact cb and all contacts of relay ZPl were closed, response circuits 1 and 2 were formed for relay An , and one response circuit is formed for each pre-test relay that is involved in controlling a target point. These response circuits 1 and 2 lead individually via the rectifiers GZrI to GIr 5 and at the same time individually via the normally open contacts 2vl, 2v2 to 2v5 of the pre-test relays. Each response circuit has its own normally open contact (16 zpl, 17zpl to 20 zpl) of the target point relay (ZPl) corresponding to the target point being controlled. These working contacts are still connected via wiring (R Vl) to lines ANl to ANn , each of which leads to one of the setting sets ESl to ESn and in this with the connection relay, z. B. AnI, is connected (see. Circuits 1 and 2). The mentioned wirings (RVl) are carried out analogously to the sequence of the selection of the pre-test bridges in the setting sets, namely the response circuits assigned to the pre-test relays Vl, V 2 to V 5 lead to the relays An of those setting sets to which those tested by the pre-test relays are also connected Preliminary test bridges belong. This becomes particularly clear on the basis of the description of circuits 4 and 5.

Thus, the contacts 16 zpl and 17zpl, which are assigned to the preliminary test relays Vl and V 2 testing the preliminary test bridges FSl and VB 2 α of the setting set ESl, are connected to the connection relay of the setting set ESl; Furthermore, the contact 20 zpl, which is assigned to the preliminary test relay VS testing the preliminary test bridge VB1 of the setting set ESn, is connected to the connection relay An of the setting set ESn (cf. circuits 1 and 2).

If the pre-test relay V2 responds when selecting the pre-test bridges, only that setting set remains connected to the marker in which the selected pre-test bridge is located, i.e. setting set ES1, since circuit 5 is only formed by this one setting set as a holding circuit for relay An will. The response circuits of the connection relays of the other setting sets, i.e. in this case setting set ESn, are disconnected again. As a result, the selection among the preliminary test bridges of different setting sets is at the same time a selection among the setting sets themselves in terms of their effect.

After one of the preliminary test bridges has been selected according to the order of preference according to which the trunk groups are suitable for the control of a destination, a free accessible line is selected from the outgoing lines corresponding to a selected preliminary test bridge. For this purpose, one of the ten marking relays in the central marker is switched on. Accordingly, the wirings (RV2) of Vorprüfrelais Vl to VS are the Ansprechstromkreise for Markierrelais, also referred to as Markierstromkreise, wired (RVi). Since when the pre-test relay V 2 responds on the basis of the target point information expressed in the target point relay ZPl, the pre-test bridge corresponding to a second column of test points Ltg 2 to Ltg 52 has been selected, the marking line Ml2 can be connected to earth potential via the contact 7zpl with the contact Iv2 . Analogous to the columns in which the pre-test bridges checked by the pre-test relays Vl, V 2 and VS are located, a corresponding one of the marking relays Ml to MIO in the selected setting set is switched on depending on the previously excited target point relay and the subsequently addressed pre-test relay. The RV3 jumper wiring is designed accordingly. The marking relay M 2 of the setting set ESl is now switched on via the following circuit:

6. Earth, Iv2, Tzpl, M12, M2 -.

This marker relay M 2 corresponds to a pre-test bridge or the pre-test bridges, one above the other in a vertically drawn column of test points, e.g. B. Ltg2 to Ltg52 lie.

Via the contacts of the marker relay in question, the test points in the column of test points corresponding to this marker relay are switched on individually to test relays Pl to P 6, provided that the test points correspond to lines that can be reached, ie those on couplers, e.g. B. £ 411 are, their associated path test relay, z. B. TfPl, is excited. So z. B. the test points Ltg2 to LtgS2 through the contacts Im2 to 6m2 of the marker relay M2

809 598/78

connected to the test relays Pl to P 6, provided that the contacts 2 wpl to 2 wp6 are closed; the test control relay PK in the setting kit has already responded in preparation after the relay on has responded, after it has been connected to the circuit

7. (Fig. 6): Earth, cb, 3vl, 2v2, 17zpl, AnI (Fig. 5): AN, xan, PK, 2p6 ... 2pl, -

got excited.

From the PrüfpunktenLig2 corresponding to 52 lines, however, only the Ltg the Vorprüfbrücke VB 2 are α been summarily selected in the adjustment set ESI corresponding lines in the selection among the Vorprüfbrücken. Since the other managerial obligations ¹ S, namely the Vorprüfbrücke VB 2 b the corresponding lines are not eligible for a connection through-connection in question, only the Vorprüfbrücke VB are used α 2 corresponding lines to selective conduction test. ao

For this purpose, the rectifier matrix connected to the jumper wiring RV4 and to the test relays of the setting sets is provided in the marker, which consists of the rectifiers Gl to G30. This matrix has RV4 ten switching points shi to SHIQ on the distribution wiring. The first switching point ShI leads to the rectifiers Gl, G6, GIl, G16, G 21, G 26 via an uninterrupted column line of the matrix. The second switching point Sh 2 only leads to the rectifiers G2 and Gl; then 3 <> this column line is interrupted. The third switching point Sh 3 leads via the second part of the interrupted second column line to the rectifiers G12, G17, G22, G27. 6 shows the connection of the further switching points Sh 4 to Sh 10 to the jumper wiring RV 4 to the rectifier matrix. Any number of the six test relays in the connected setting set can be effectively switched via the ten switching points. So over the first switch 4 <> point z. B. all six test relays, the test relays Pl and P2 via the second switching point, the test relays P3, P4, PS and P 6 etc. via the third switching point. In the functional example described above , the outgoing lines corresponding to the preliminary test bridges KBl and VB 2 in the setting set ES1 and the preliminary test bridge VBl in the setting set ESn are available for selection to control the target point 1. According to the pre-test relays Fl, F 2 and V 5 selected from these three pre-test bridges, the contacts lzpl and 5zpl of the target point relay ZPl connected to the contacts IvI and Iv5 of the pre-test relays Fl and VS are connected to the first switching point via the jumper wiring RV 4 , via the all six test relays P1 to P 6 are effectively switched, because the pre-test bridges FS 1 checked by the pre-test relays F1 and F 5 in this case in the two setting sets ES1 and ESn are not subdivided. As already described, the preliminary test bridge VB2α has been selected in the setting set ES1. The preliminary test bridge, which corresponds to the second column, is divided into the preliminary test bridges VB 2 a and VB2b. Since the pre-test bridge VB 2 α was selected in the pre-test by the pre-test relay F 2, the contact Iv2 of the pre-test relay F2 is via the contact 2 zpl of the target point relay ZPl and via the jumper wiring RV4 and the fourth switching point with the rectifiers G 3, G 8 and G13 connected via which the first three test relays Pl, P 2 and P 3 are activated. Despite the fact that the contacts Im2 to 6m2 of the marker relay M2 may have previously switched all test relays Pl to P 6 to all test points Ltg2 to Ltg52 of this column, only the three outgoing lines corresponding to the preliminary test bridge FjB 2 ß are subjected to a selective test (provided that the corresponding Contacts 2wpl etc. are closed).

Of the three effectively switched test relays Pl, P2 and P3 (P2 and P3 are not shown) those excited that are interconnected with free lines that can be reached via the switching network. It is assumed that the three mentioned relays are energized and respond. Only the response circuit of the test relay P1 is named below:

8. (Fig. 6): Earth, Iv2, 2zpl, (Sh4), G3, PAl (Fig. 5): PAl, Pl, Ipk, ImZ, 2wpl, Ltg2,

The relay Pl forms a holding circuit via its winding and its contact IpI to the negative potential:

9. (Fig. 6): Earth, Iv2, 2zpl, (Sh4), G3, (Fig. 5): PAl, Pl, IpI, -,

and separates the excitation circuit 7 of the relay PK at the contact 2p 1, so that it drops out; Furthermore, by opening the contact 2p 1 prevents the other two test relays P 2 and P 3, not shown, also from being able to form holding circuits. The test control relay PK drops out, opens its contacts IpA: to 6pk and closes its contact Ipk. Of the test relays addressed, only the first one remains energized in its holding circuit, whereas the others drop off again because they could not form any holding circuit. The contacts 2p 1 to 6p 1 thus represent a selection contact chain.

After the relay PE! At the same time, a test circuit is formed by closing the Ipk contact:

10. (Fig. 6): Earth, Ph, ph (Fig. 5): Ipk, 3p 1, Im2, 2wpl, Ltg2, ..., -.

The outgoing line connected to the test point Ltg2 is now subjected to a re-test, whereby a parallel test (double connection), testing for a test line in a triggering connection (incorrect connection) and the like can be avoided with the greatest possible degree of certainty. Verification circuits are already known, e.g. B. by the German Auslegeschrift 1170 015. If this check leads to a positive result, the contact phl closes (in Fig. 3) in the central marker Zm, is applied to the ground potential in the output coupling group AKGl . This switches on the response circuit for the coupling relays of all coupling stages. For this purpose, however, a route selection takes place beforehand, which is then described before the description of the response circuits is continued.

First of all, it should be remembered that through the one addressed test relay Pl a single specific, namely the first coupler, z. B. K411, the output coupling group, such as AKGl, is designated. Furthermore, a specific output from this coupler, to which the selected free line is connected, is designated by the one addressed marking relay M2 with its contact Im2. This free line is due to the consideration of the result of the route search process (response of route search relays, e.g. WPl) when selecting a preliminary test bridge corresponding outgoing lines and when selecting a single free of these with certainty also via the switching matrix. This accessibility relates to the entire coupler to which this one selected free line is connected.

It is now possible that several paths in the switching network can be switched through between the incoming busy counting pulse generator Zig and the coupler K 411. Assuming that the incoming busy counting pulse generator Zig in the first coupling stage KA (Fig. 2) is connected to the coupler Kill , routes via the intermediate lines ZLl and ZLlO in the intermediate line field Z2 in FIG individually between the couplers .Oll and £ 211, further £ 111 and £ 210, further £ 311 and £ 411 and further £ 310 and £ 411 each are free. These two paths (there can also be more free paths to choose from) do not overlap in the switching matrix and only meet at the couplers £ 111 and £ 411. This is ensured by the grouping shown in FIG. One of these routes is selected at the coupler to which the previously selected free, accessible, outgoing line is connected by selecting one of the incoming intermediate lines of the intermediate line field Z 3 connected to this coupler (£ 411) that carries the path search potential. The path search wires connected to this coupler and corresponding to the intermediate lines in the intermediate line field Z 3 are shown in FIG. 4 shown. They are brought together at the WPl route search relay. The fact that this is a coupler £ 411 is, as already described, from the response state of the test relay Pl, whose contacts 4 p 1 to 13 ρ 1 connect the route search wires with the route selection relay JVl to NlO in the central marker Zm individually. Like the route search relays WP1 to WP 6 , these route selection relays are initially high-resistance and likewise do not load the route search cores with regard to current. Of the route selection relays, after the test relay Pl has been addressed, those who find route search potential on the corresponding route search cores speak to them. It is assumed that the route selection relays Nl and respond via the following circuit:

11. (Fig.4): Earth, w / zl,

Nl (I), Nl (Il), 4pl, / 311/1, Gw311 / 1, WKZIl (Fig. 3): WKZIl, LH,

JVlO (I), NlO (II), 13ρ 1, / 310/1, Gw 310/1, 1/211, G / 12, WK2U, 11, Gill, WKUl, ... (Zig) ... _ WK310 , ... (accordingly) ... '

A response circuit is established via contacts 3 «1 and 3 η 10

12. (Fig. 4): Earth, - ^ jL, »Ή, -

formed for the auxiliary route selection relay WH , which responds and disconnects the circuit 11 of the route selection relay with its contact whl again. A structurally secured contact sequence ensures that contact wh 2 closes before contact whl is opened, whereby the chain of changeover contacts 1 ttl, 2nl, In2, 2n2 to 10-2 is connected directly to earth potential. The first addressed route selection relay, i.e. Nl, is connected with its low-resistance holding winding (II) to the corresponding route search wire connected via contact 4 p 1, while the other addressed route selection relay N ... drop out again. By the addressed route select relay Nl ground potential of the test is a low impedance at the routing wire over the contact 4 pl relay Pl. This routing wire is energized to the routing node WKlU in the routing network via the routing node WK211 and JF £ 311 and via link ZLL in the intermediate line field Z2 (s Fig. 3). The intermediate line auxiliary relay LH in FIG. 1 speaks in the path search vein that is assigned to the intermediate line ZL1. 3 across the circuit

13. (Fig. 4): Earth, wh2, 2nl, Nl (Ii), 4pl, / 311/1, Gw 311/1, PF £ 311 (Fig. 3): WKZIl, LH, 1/211, G / 12, PF £ 211, 11, Gill, WKlIl, (Zig),

at. Through the contact 2 lh of the relay Li? earth potential is connected to the response wire (Fig. 3) of the same intermediate line via the contact phl.
Let us now consider the case that between each coupler of the one and each coupler of the other switching stage within each switching group and between each coupler of the second and each corresponding coupler of the third switching stage there is only a single intermediate line. In this case, there is only a single link available in each of the link fields Z1, Z 2 and Z 3 for the switching path described from coupler £ 111 to coupler £ 411 via couplers £ 211 and £ 311. By selecting the intermediate line ZL1 in the intermediate line field Z 2, the intermediate lines in the two intermediate line fields Zl and Z 3 are therefore also clearly determined. Furthermore, the coupling relays that are to be switched on for switching through the connection are also marked by the intermediate lines and the specific input and the specific output.

Thus, negative voltage potential reaches the response coils of the coupling relays D ... of the second column of coupling relays, not shown, to which the designations D 2, D12, D 22 to D 29 would correspond analogously via the contact 14ρ 1 in FIG. Since the connection must also take place via the coupler £ 311 of the coupling stage KC, consequently via the first intermediate line, only the coupling relay belonging to the first row in the second column of the coupler £ 411 can be used for the connection.

Due to a similar coordinate condition in the coupler £ 311, the coupling relay Cl is required for the

circuit determined. The coupling relay Cl and the coupling relay D 2, not shown, are energized and they respond via the following circuit:

14. (Fig. 4): -, 14 ρ 1, TmI (not shown, but analogous to 7ml and Tm 10), (further see Fig. 3): Eq4, D (II), G / 3, C (II ), 2 lh, phl, earth.

del BdI and which are assigned to the preliminary test bridge KBl in the setting set ESn , at least one line, for example the lines corresponding to the test points Ltgl and LtgSl , free, the relay VS in the central marker is excited via a current relay analogous to the circuit 4, so that it responds and is held in a circuit analogous to the circuit 5. By opening contact 3v5 of relay VS , circuits 1 and 2

In the same way, certain coupling relays in coupling stages A and B are excited and respond. So that the way in the signal wires, z. B. speech cores switched through. The coupling relays also form a corresponding holding circuit consisting of two branches across all coupling stages: ^1S

15a. -, (Zig), A (T), «3, Ll, B (I), b3, LlIl, earth;

15b. Earth, 2/211, C (I), c3, L3, D (I), d3, ff, -.

This holding circuit, which consists of two branches (15 a and 15 b), contains in each coupling stage the holding coil (I) of the coupling relay and a relay's own working contact connected in series with it. The holding circuit also contains the intermediate line relays Ll ₅ L 211 and L 3 located in the intermediate line fields, which also respond and indicate the busy state of the intermediate lines by opening their normally closed contacts / 1 and 1 311/1 located in the path search wires. Furthermore, the holding circuit leads via the winding ff of an auxiliary relay ff assigned to the relevant output of the coupler of the fourth coupling stage, which also responds. A relay ff is assigned to each output of each coupler. In Fig. 5 takes this into account by numbering the contacts h ... of the auxiliary relays assigned to each output as well as the test points Ltg ... of the outgoing lines. The auxiliary relay ff of the newly occupied outgoing line responds and closes its contact / i2 (in FIG. 5), whereby earth potential is connected to the test line of the occupied line as an occupancy potential. The checking circuit Ph in the central marker is thereby put back into its idle state, as a result of which the central marker and the setting set return to their idle state in a manner not shown and described. By opening the contact lph of the verification circuit Ph , the circuit 14 is also de-energized; the intermediate line auxiliary relay Lff is also shown in FIG. 3 dropped. As a result, the route search artery of the newly occupied intermediate line in the intermediate line field Z 2 is also disconnected for the purpose of identifying the busy state at the contact 11h . Furthermore, the response circuit 14 is separated again so that the coupling relays addressed only remain energized in their holding circuit.

In the event that in the mentioned line bundle BdI, i.e. under the two groups of lines that correspond to the preliminary test bridges FBl and FB 2 in the setting set ESl , no line is free and accessible - so some can be free, but not reachable or reachable, but not be free - neither the pre-test relay F1 nor the pre-test relay F 2 responds during the group test process. Is in the group of lines that the line bundle is held via a circuit analogous to circuit 5, while the relays An of all other setting sets, here setting set EsI, are thrown off again and cause the relevant setting sets to be triggered.

One of the free accessible lines of the line bundle BdI is selected in the manner already described. Since the lines of the cable bundle BdI are assigned to the first outputs of all couplers K4nl to K4n6 of the output coupling group AKGn , the relay Ml in the setting set ESn is energized via a circuit analogous to circuit 6, and all test relays Pl to P 6 are analogous to circuit 8 Circuit effectively switched, which, in deviation from circuit 8, runs via contacts Iv 5, Szpl, switching point £ M and rectifiers Gl, G6 ... to G26. The test relay Pl responds and initiates the connection, as has already been explained in detail above.

In the event that destination 2 is to be approached as the destination, the switching processes are very similar. The target point relay ZP 2 responds and switches the preliminary test relays Fl, F2 and V5 to the preliminary test bridges FBlOa in the setting set ESn, VB2b in the setting set ESl (these two preliminary test bridges correspond to two groups of lines that together represent the bundle of cables Bd 3) and to the preliminary test bridge FBl in the setting set ESn, which corresponds to the trunk group BdI. First, the relays operate on the two setting sets ESI and ESn, said lines are turned on in their associated output coupling groups AKGl and AKGn, as already described. Corresponding to the preliminary test relays F1, F 2 and F 5, lines of the groups of lines corresponding to the three mentioned preliminary test bridges are now available for switching through for selection in a group testing process, provided that lines are free and accessible. If lines of the line bundle Bd 3 in the group of lines corresponding to the preliminary test bridge VBlOa of the setting set ESn are free and accessible, the preliminary test relay Fl responds in a circuit analogous to circuit 4 and forms a holding circuit analogous to circuit 5 via its own contact 2vl. Furthermore, a response circuit analogous to circuit 6 for relay MIO of setting set ESn is formed via contacts IvI and 6zpl. In addition, the test relays Pl to P 4 are activated via the contacts IvI and 1 Zp 2 and the switching point Sh6 and the rectifiers G6, GU, G16, G 21, which test lines (cf. circuits 8 and 9). The relay An of the setting set ESl drops out as a result of the opening of contact 3vl. The group of lines corresponding to the preliminary test bridge FB10a in the setting set Es η is thus selected by the group test process.

If, on the other hand, at least one line is free in this group of lines, but in the group of lines of the line bundle Bd3 corresponding to the preliminary test bridge VB 2 b of the setting set ESl, the preliminary test relay Vl responds, forming a holding circuit for the relay An of the setting set ESl and lets the relay A η of the setting set ESn drop out. In the same way as described above, the relay M2 in the setting set ESl responds , and the test relays P 4, PS and F 6 of the same setting set are activated [contacts 1 ν 2 and 7zp2 for the relay M2; Contacts Iv2 and 2zp2, switching point ShS, rectifiers G18, G 23, G 28 for the relays P 4 to P 6 (see circuits 6, 8 and 9)]. The group of lines corresponding to the preliminary test bridge VB 2 b in the setting set ES1 is thus selected by the group test process.

On the other hand, it is not in this group of lines, but in the group of lines corresponding to the preliminary test bridge VB1 of the setting set ESn

of the line bundle BdI at least one line free, the preliminary test relay VS responds, forms a holding circuit for the relay An of the setting set ESn and lets the relay An of the setting set ESl drop out. In the same way as described above, the relay Ml responds in the setting set ESn , and the test relays Pl to P 6 are activated [contacts Iv5 and 10 zp 2 for the relay Ml; Contacts Iv5 and Szp2, switching point ShI, rectifier Gl,

ίο G 6, GIl, G16, G 21, G26 for the relays Pl to P6 (see circuits 6, 8 and 9)].

The described selection processes among groups of lines depending on destination information and depending on a target-point-dependent ranking order in which from the mentioned groups of lines into question existing line bundle for establishing a connection are summarized below in a table that provides an overview of the

ao should give selections.

Destination information Target point 1 VBl ZPl VBl VBlOa Target point 1 VBl Responsive destination relay ESl BdI, BdI ESn ESn ZP 2 ESn Eligible trunk groups Vl Bd2, BdI V5 Vl VS Line bundle sorted according to order of precedence Ml VB2a Ml MIO Ml Preliminary test bridges, which groups from Leitun
corresponding to this bundle of lines ShI ESl ShI Sh 6 BdI, Bd3 ShI Affiliation of these preliminary test bridges to Ein
setting sentences PlbisP6 Vl PlbisPG PlbisP4 BdZ, BdI PlbisP6 Testing pre-test relays M2 VBIb Responsive marking relays ShA ESl Effective switching point PlbisP3 Vl Actively switched test relays (partly not
shown) Ml Sh 5 P4 to P6

Then, with regard to the route selection in the switching network, the case is considered that between two couplers of successive coupling stages, e.g. between couplers £ 211 and K 311, furthermore couplers £ 210 and £ 310, etc., more intermediate lines are provided than just one a single one. So in the mentioned switching network between two couplers of adjacent switching stages z. B. four intermediate lines can be provided. In particular, intermediate lines in the switching network are arranged to run parallel in this way when such a switching network is already being operated in the stage of partial expansion. As a rule, this is temporarily always the case in any such switching system. So lead at a z. B. only 50% partial expansion of the entire switching network, the outputs of each of the switching groups in the first two switching stages to inputs of only half as many output switching groups as in the final expansion; However, since all outputs of the couplers of the second coupling stage in each coupling group should be connected to inputs of the couplers of the third coupling stage via intermediate lines, two intermediate lines must always be routed in parallel in the previously described manner in the intermediate line field Zl.

The in F i g. The grouping shown in FIG. 2 is now retained in this way even in the case of partial expansion, because it is very advantageous for the described route search and route selection. It would be conceivable, with an increase in the intermediate lines lying between two specific coupling groups in the intermediate line field Zl , to deviate from the intermediate lines only between corresponding couplers, e.g. B. £ 211 and £ 311 as well as £ 210 and £ 310, but additional intermediate lines between these two coupling groups in the case of partial expansion, e.g. B. between the couplers £ 211 and £ 310 or £ 210 and £ 311 etc. to be arranged. However, this option is expressly refrained from, as the grouping according to FIG. 2 given advantage not to be forfeited. If the principle of grouping according to FIG. 2 retained even with partial expansion, the principle of route search and route selection can be retained to the effect that when route selection, as already described, at a coupler of the fourth coupling stage, z. B. £ 411, the coupler of the second and third coupling stage can be clearly determined via which the connection is to be switched through. Is z. If, for example, a line leading to the coupler £ 310 is selected when selecting the route on the coupler £ 411, then this coupler is first determined in the third coupling stage and in the second coupling stage depending on the coupler £ 310

809 598/78

27 28

and the coupler £ 111, to which the occupied counting levels KA and KB, each with two different

pulse generator is connected, only the coupler £ 210 different outputs and two different inputs

suitable for switching through, so intended for this purpose. went. Therefore, there is only one response to each of the two are now still in the intermediate line wheels in each of the two coupling stages a multiple

Fields of several, between the same couplers, shown with 5 symbols. The structure of this coupler

z. B. £ 211, £ 311, parallel intermediate lines and the connection of the intermediate lines to them

lines to select a free one. For this purpose, the in on the basis of FIG. 4 and its description is very

F i g. 8 shown circuit arrangement, which has an illuminating,

Speaking extension of the F i g. 3 represents. Furthermore, in Fi g. 8 one through all coupling stages

It is assumed that the path search wire leading through the couplers £ 111 io is shown which

Coupling cores of up to £ 110 and £ 211 to £ 210 are assigned to the same intermediate lines

group of each coupler of the first coupling stage is closed. The route search nodes WKlIl ', WK211', WK31V

each coupler of the second coupling stage two intermediate and WK411 ' correspond to the couplers £ 111,

lines run parallel. Also consider- £ 211, £ 311 and £ 411 and are opposite the

assume that each coupler of the second coupler 15 representation of the path search node in FIG. 3 un-

pelstufe to each corresponding coupler (eg remained unchanged. In the link fields

the couplers £ 211 and £ 311 speak or they are, however, the route search wires for each individual

Couplers £ 210 and £ 310 each other) on the third coupling line. Because the intermediate lines

four intermediate lines each run in parallel. run parallel to the same couplers run

As with the previous one, each intermediate line also leads its individual path search arteries from

single arrangement described heretofore (FIG. 3) from and to the same route search node. So in the interim

Intermediate lines from a single output interconnection field Zl two path search cores between

a coupler to a single input of the route search node WKlIl ' and WK21V and im

Coupler. Parallel intermediate lines lead intermediate line field Zl four path search cores between

from different outputs of a single coupling 25 see the path search node WKZW! and! ^ £ 311 '

lers to different inputs of a single coupling provided. These are two or four path search arteries

lers of the next coupling stage. recognizable by the fact that they individually have windings

In Fig. 8, similar to Fig. 3, runs from each of intermediate line auxiliary relays LhI and LhI or coupling stage KA to KD or from each intermediate Lh 3, Lh 4, Lh5 and Lh6 .
Ieitungsfeld Zl each a coupling point (coupling is 30 In Fig. 8, as already stated, the Darrelais) to Z3 shown or an intermediate line or more, depending on position of the switching relay Ansprechstromkreise running parallel to the intermediate lines. The head and path search circuits are limited. The holding relay in the four coupling stages KA, KB, KC and circuits are not shown; they are also KD based on the illustration in FIG. 3, as shown in FIG. 3 shown. From this is to with A '. B ', C and D' can be seen in a corresponding manner that each holding wire of each of them is a double. Likewise, the couplers of the four rule lines are each a single link relay, coupling stages corresponding path search nodes in z. B. Ll, L 211, etc., is assigned individually. Based on the illustration in FIG. 3 with These intermediate line relays are characterized by WKlU ', WK21V, WKTiIV and WKAlV denote their response state the occupied state of a Zwinet. In FIG. 8, however, the illustration is on the connection line. The contacts lZlll / 1 and 2/111/1 speech circuits of the coupling relays and contacts search circuits are limited to path on the one hand and Il 111/2 on the other. of two in Fig. 8, not shown, individual

An intermediate response circuit running in parallel through all four coupling stages is shown in its entirety, i.e. lines in the intermediate line field Zl. The same applies to coupling relays A ', B', C and D ' with in series 45 for the contacts 1Z211 / 1 to 1111114 im Intermediate rectifiers GlV, GIl ', G13', GW. In line field Z2.

the represented contact line of the intermediate line Each intermediate line basically corresponds to

in the intermediate line field Zl there is also a contact an intermediate line relay, e.g. Ll, and in the intermediate

3lhl , which is described below. Sub-line field Z2 also has an intermediate

ter that fully through all coupling stages 50 line auxiliary relay Lh (Fig. 3). Furthermore

running response line is a second response (Fig. 8) is also in the intermediate line fields Zl

veins shown, which in the intermediate line field Zl one and Z 3 of each intermediate line an intermediate line

second intermediate auxiliary relay running parallel to the first, e.g. LhI, LhI, assigned if between

line is assigned. The two address wires are seen as the same coupler as several intermediate lines

so listen to two intermediate lines that run parallel 55 parallel.

from a single coupler of the first coupling stage, the path search arteries running parallel between B. Kill, run to a single coupler of the second interconnections, as shown in FIG. B. Kill . The same applies to the winding of the associated intermediate line for the four response wires of four intermediate line auxiliary relays LhI and Lh 1 or Lh 3 to Lh6, to two conditions, which are also connected in parallel by the coupler of the two. B. Kill, to a coupler of the interline relays and intermediate line auxiliary relays. third coupling stage, e.g. B. £ 311. These four contact chains are used to select a route.Response cores are individually connected to four contacts 3 lh 3, 3 lh 4, between each pair of couplers 3 lh 5 and 3 lh 6, which are later carried out in one intermediate lines, if the individual has already been described will. 65 Durchschalteweg in the coupling field with regard to the to The response wires of the first two intermediate-using couplers through the central marking lines lead from the intermediate line field rer with the help of relays Nl to iVlO to the same couplers in the coupling path selection has been determined.

If a connection is to be carried out via the couplers KUl, K211, K311 and K 411 and all intermediate lines are free, the intermediate line auxiliary relays LhI and Lh 3 in the following circuit are energized after a route selection by the route selection relays Nl to iVIO on the route search wires of a coupler:

16. (Fig. 4): Earth, wh2, InI, Nl (II), ApI, / 311/1 (ie in Fig. 8/311 / Γ), (further Fig. 8): Eq 13 ', WK 31Γ , LA 3, 1/211/1, 2lh6 ... 2lh3, Gl 12 ', WK 211', LhI, 1/111/1, 2 / ft 2, 2 IhI, GUI ', WKlW, ..., - .

The relays LhI and Lh3 respond. With their contacts 3 IhI and 3 lh3 they close the response circuits for the coupling relays A ', B', C ", D ':

17. (Fig. 8): Earth, lph, 3lh3, 23 '(II), G / 2', _ao 3 IhI,, 4 '(1I), GIl', ..., -.

18. Earth, lph, 3lh3, C (II), G / 3 ', D' (II), G / 4, ..., IpA, -.

Likewise, when the relays L / il and Lh3 responded, their changeover contacts lZ / zl, 2 / Al and Ilh3, 2 / A 3 were actuated. These converted circuit 16 into the following circuit in which these intermediate line auxiliary relays are held:

19. (Fig. 4): Earth, wh2, 2nl, Nl [Il), ApI, / 311 (ie in Fig. 8/311/1 '), (further Fig. 8): G / 13', WK31V, Lh3, l // i3, G / 12 ', WK21V, LhI, Uh 1, GIlV, WK 111', ..., -. ³ pp

If the coupling relays respond, they form, as already shown in FIG. 3 described, the common holding circuit consisting of two branches (see. Circuit 15 a and 15 b), in which the intermediate line relays are located and respond. Accordingly, the changeover contacts 1/111/1 and 2/111/1 on the one hand and 1/211/1 and 2/211/1 on the other hand open their idle sides and close their working sides. Furthermore, this also speaks in FIG. 3 shown auxiliary relay H in the holding circuit, through which the setting set and the central marker are returned to their idle state in the manner already described, so that the circuit 19 is also disconnected again and the relays LA1 and LA 3 drop out again.

If some of the parallel intermediate lines are already occupied when the connection is switched through, the associated intermediate line relays are also energized and their contacts actuated. Are z. B. the contacts 1/111/1, 2/111/1, 1/211/1, 2/211/1 actuated, then after a route selection through the relays Nl to NlO, of which z. B. the relay Nl was energized and responds, the following circuit is formed:

20. (Fig. 4): Earth, wA2, 2nl, Nl (II), Ap 1, / 311 (ie in Fig. 8 1311/1 '), (further Fig. 8): G / 13 ', WK 311', LA 4, 1/211/2, 2/211/1, 2 lh 6, 2lh5, 2IhA, 2 / A3, G / 12 ', WK211', LA 2, 1/111/2, 2/111/1, 2 / A 2, 2ZAl, G / 11 ', WK 111', ... , (Zig), -.

In this circuit, the relays LA 2 and LA 4 respond and act accordingly as described above Way the connection via the coupling relay and via the im Circuit 20 called intermediate line auxiliary relay LA 4 corresponding intermediate lines.

Through the intermediate line auxiliary relays, e.g. B. LAl to LA 6, so the criterion indicating the result of the route selection, namely the low-resistance through-connection of the through- connection path running through certain couplers, is recorded by contacts 2nl to 2 η 10 in FIG Contacts, e.g. 3 / A3 to 3 lh 6, marked; In this case, the intermediate line relays and intermediate line auxiliary relays make a selection from, if necessary, several free intermediate lines running in parallel. This marking with the aid of intermediate line auxiliary relays is therefore generally carried out in the second intermediate line field Z 2 (cf. FIG. 3). If, in addition to the marking, a selection from several parallel intermediate lines is required, this can be done in the intermediate line field with the aid of the intermediate line auxiliary relays, e.g. LA3, LA4, LA5, LA6. Is how F i g. 8 shows that this selection among parallel intermediate lines also in other intermediate line fields, e.g. B. Zl, required, this can be done with the help of specially provided intermediate line auxiliary relays, z. B. LAl, LA 2, are made.

It can now be assumed with certainty that the switching groups comprising the first and second switching stage KA, KB or third and fourth switching stage are always designed for the final stage of expansion of a switching system and that the stage of partial expansion of the switching system by a correspondingly smaller number of these Coupling groups is taken into account. This means that no parallel intermediate lines have to be provided within these coupling groups. Intermediate lines running in parallel are therefore generally only to be provided in the intermediate line field Z 2. In this intermediate line field, however, in addition to one intermediate line relay, one intermediate line auxiliary relay is also provided for each intermediate line for marking purposes. Advantageously, these intermediate line auxiliary relays can be used not only for marking purposes but also to select routes among parallel intermediate lines.

Claims (14)

Patent claims: 1.Circuit arrangement for telecommunications switching systems, in particular telephone switching systems, with switching matrices, which are made up of several switching stages, via intermediate lines Interconnected couplers exist and in which in each case a connection through-connection previous path search process a free path via intermediate lines and couplers for a required connection is selected, characterized in that in a first selection process, the from one that takes into account the state of the entire switching network (intermediate lines free or busy) Finding the way is dependent, all for one Connection via the switching matrix (KF) from one of its inputs (according to Zig) to one of its outputs (according to line ) necessary coupler (e.g. £ 111, £ 211, £ 311, £ 411; one in each of the coupling stages) by selecting 5 one single intermediate line (e.g. that running between couplers £ 311 and £ 411) or a coupler (e.g. £ 311) in a single coupling stage (e.g. £ 3) can be determined that (cf.F i g. 8) between each the two specific couplers (e.g. £ 211, £ 311) of two adjacent coupling stages (£ 2, £ 3) several parallel intermediate lines are combined to form a group of intermediate lines and that independently of one another and simultaneously ongoing second selection processes per group, a free intermediate line of the respective group is selected depending on the status (whether free or busy) of all of its intermediate lines. so 2. Circuit arrangement for telecommunications switching systems with switching fields in which the Intermediate lines are individually assigned to intermediate line · * relays, each of the state (whether free or occupied) of the intermediate line by their state of excitement (not addressed or addressed) show, according to claim 1, characterized in that intermediate line relay of intermediate lines of a group with their contacts (e.g. 1/211/1, 2/211/1 to 1/211/4) are interconnected to a known selection contact chain, their respective setting denotes one of the free intermediate lines. 3. Circuit arrangement according to Claim 2, characterized in that, with the contacts (e.g. 1/211/1 to 1/211/4) of the selection contact chain, which individually indicate the free state of the intermediate lines, windings from the intermediate lines are also individually assigned intermediate line auxiliary relays (e.g. B. Z / z3 to Zh6) are interconnected and that contacts (z. B, 2lh in Fig. 3) of these are individually connected to the response circuits assigned to the intermediate lines for coupling relays in the couplers. 4. Circuit arrangement according to claim 3, characterized in that the intermediate line auxiliary relay (z. B. Lh3 to Lh 6) and the contacts connected in series with them (eg 1/211/1, 2 Z 211/1 to 1/211/4 ) the link relay are in a marking circuit, via which the result of the first selection process is signaled. 5. Circuit arrangement according to claim 4, characterized in that the marking circuits are the route search cores of the intermediate lines. 6. Circuit arrangement according to claim 3, characterized in that excited and addressed Intermediate line auxiliary relay (e.g. LH 3) temporarily via a relay's own contact (e.g. l // z3) form a holding circuit and the Override the selection contact chain of the intermediate line relay contacts. 7. Circuit arrangement according to claim 1, characterized in that the path search taking into account the state (intermediate lines free or occupied) of the entire switching matrix (KF) is limited to switching matrix outputs (KF, right-hand side) connected to such lines (Ltgl to Lig60), which both are free as well as determined by the respective available election information. 8. Circuit arrangement according to claim 7, characterized in that for each coupler (e.g. K 411) of the last coupling stage (KD) path search switching means (e.g. WPl) are provided which conduct a line test for the lines connected to the same coupler ( z. B. Ltgl to prepare cond 10). 9. Circuit arrangement according to claim 8, characterized in that contacts (e.g. 1 wp 1, 2wpl , .. IOwpl) of the path search switching means ( e.g. WPl) in the test circuits of those outgoing lines ( e.g. Ltgl, Ltg2 ... LtglO) which are connected to the coupler (e.g. K 411) to which this route search switch (WP 1) is individually assigned, 10. Circuit arrangement according to claim 9, characterized in that the line test consists firstly of a group test process and secondly of a single line test, that the group test process consists of several (z. B. 2) groups (z. B. first Ltgl to LtgSl, second Ltg2 to Ltg52) of several lines each one of these groups ( e.g. Ltgl to Ltg Sl) is selected, which contains at least one free accessible line (z. B. Ltgl and Ltg Si) , and that by the individual line test within the selected group one free reachable line ( e.g. Ltgl) is selected. 11. Circuit arrangement according to claim 10, characterized in that a line bundle (z. B. Bd2) consists of one or more groups of lines. 12. Circuit arrangement according to claim 11, characterized in that of the lines of a group (z. B. Ltgl to LtgSl) in each case at most one (z. B. Ltgl) connected to the output of a coupler (z. B. £ 411) is. 13. Circuit arrangement according to claim 12, characterized in that a single line test (for example on Ltgl) determines that coupler (e.g. £ 411) via which a selected connection is to be switched through. 14. Circuit arrangement according to claim 13, characterized in that a chain of test switching means (F1 to P 6) is provided for individual line testing, which enables a simultaneous test of all lines (eg Ltgl to Lig51) of a group. For this purpose 2 sheets of drawings 809 598/78 8.68 © Bundesdruckerei Berlin