DE608415C - Arrangement for remote control and remote monitoring of railway switches and signals - Google Patents

Description

The invention relates to an arrangement for remote control and remote monitoring of railway switches and signals depending on the traffic conditions, at which one for each device to be monitored is usually one open, manually operated switching device is arranged at a central monitoring point and the short-term Closing this switching device causes the continued excitation of a control relay, that causes the controlled device to be changed and then monitors it, until the train journey or a corresponding process is completed and then the system returned to their original position. It is therefore a remotely controlled and remotely monitored Switching device in which a single contact is made with the help of control monitoring relays a changeover automatically

ao takes place and this change is eliminated when the train journey is completed.

In the case of electrical power distribution systems with substations, on which switching devices are provided, they are controlled remotely

Devices from the central monitoring point by sending key streams after the substation under supervision by relays and buttons. The devices at the substations must be brought into one or the other of two positions, and there are relays that do this Corresponding positions, provided in the monitoring point, so that the conversion of the device or the withdrawal of a position by pressing the corresponding key with Excitation of the appropriate relay can be effected. The withdrawal of a position of Device is thus only by changing the switching device in the central Monitoring point causes.

In the case of remote control of railway switches and signals, their resetting is effected by the train itself, and when using the relay chains as controls find, as is the case with the subject matter of the invention, the conditions are completely different, and it is desirable here to create arrangements for a control process at the central point independently of the Effect of a changeover of the device to be withdrawn by means of a driveway.

According to the main feature of the invention, another, usually closed, in the current flow of the control relay

Device provided with manual operation that allows an already initiated To withdraw the changeover movement, provided that the; allow the traffic or operating conditions.

The invention is illustrated for example in the drawing, which consists of two parts Existing single figure is a schematic view of an embodiment of the invention ίο shows.

In. the drawing form the rails of a twin-track railway track ι, ^ΐ α, ι "two tracks Y and Z, which are interconnected by a connecting track X. An ι one end of the Verbmdungsgleises is the switch W ¹ and at the other end of the switch W ^2. Track Y is divided into sections aA, AC and CD by means of insulated rail joints 2, and track Z is divided into sections fF, FG and GH in a corresponding ao manner by means of insulated rail joints 2. Each of these sections is connected to a rail circuit which includes a rail relay T ¹ , T ² , T ^s , etc. connected to the rails adjacent one end of the section, and power is supplied by a track battery 3 connected to the rails near the opposite end of the section in question The sections aA, CD, fF and GH which are behind signals which are arranged at A, C ₁ F and G are as access sections, and the sections AC and FG In which the foundations are, known as Gleisverbindungs- or driveway sections.

The signals S ¹ and S ² regulate the eastward traffic from A on track Y to the right. The signal S ⁶ regulates the eastward traffic from G via the track Z. The signals S ³ , S ⁴ , S ⁵ regulate the westward traffic on the tracks Y and Z in a similar way. The signal S ¹ regulates the traffic via track Y from A via C when the switch W ¹ is in its normal position shown in the drawing. The signal S ² regulates the traffic from A via the switches PF ¹ and W ^z when these switches are switched. The signal S ² is also used as a call signal for the regulation of the traffic from A over the normally standing points W ¹ , W ^% ; if the traffic conditions prevent a color display by the signal S ¹ . The signal S ⁵ regulates the westward traffic over the switch W ² in its normal position shown. The signal S ⁴ , similar to the signal S ^2, regulates the traffic via the switched points W ¹ and W ² , and if the traffic conditions ^{prevent the signal 5} from displaying the journey, the signal S ⁱ creates a call sign for the traffic via the switches W ² , W ¹ .

Each of the switches W ¹ and W ² can be operated by any suitable means, such as. B. by an electric motor. A polarized switch relay m is energized by current of normal or reverse polarity, depending on whether a pole changing device Q is in its normal position shown or in the reversed position. The actuating device for the switches W ¹ and W ² moves the latter into the normal or reversed position, depending on whether the switching relay m is energized in the normal or reverse direction.

The access blocking of switches W ¹ and W ² is completed with the aid of delay relays P ¹ , P ³ , P ⁵ and P ⁶ , which are combined with the signal or signals at A, C, F and G , respectively. Each of these relays is monitored in such a way that it is de-energized when the control relay is energized for an associated signal to cause the signal display "driving". Each access lock relay can then be re-energized if the access track section for the associated signal is free, or if a route section served by the signal is occupied while the control relay for the signal is de-energized. In an emergency, a time release device J ¹ , J ⁵ can be used to energize a corresponding access lock relay when the control relay for the associated signal is de-energized.

The device Q is removed from the monitoring circuit of the relay m if one of the route sections AC and FG is occupied or if one of the access blocking relays is de-energized. The relay »then remains energized by a delay circuit, which leads via one of its own armature contacts and a break contact of a route section relay or an access blocking relay.

A display relay i is connected in series with the relay m in the delay circuit for the latter and monitors a display device, e.g. B. an electric lamp d.

A polarized switch indicator relay K is controlled by the switches TF ¹ and W ^{2 in} such a way that it is energized ¹ in the normal direction when both switches W ¹ and W ² are in their normal position and that it is energized in the opposite direction when both points are in the folded position. The monitoring circuits for the relay K and the actuating circuits for the switches W ¹ and W ² in their monitoring, which are monitored by the switching relay Ot, are well known and are therefore omitted from the drawing.

Each signal is monitored by a signal relay R ¹ , R ² , R ³ , etc., and these relays are in turn monitored by corresponding delay relays I ¹ , 1 ² , J ³ , etc. Each

this delay relay, such as relay I ¹ , has a working circuit that is monitored by a device, which is shown here as a push button contact U ¹ , the S is only closed when it is held in its closed position by hand, and also has a Delay circuit that is monitored by a route relay and by a device that is shown here as a pushbutton contact (7 ^a , which is always closed, except when it is held open by hand. The signal relays are monitored by contacts, except for the delay relays, through the turnout display relay K, operated by the track relay T, the access lock relay and the time release devices.

In series with each signal relay i? ¹ , R ³ etc. there is a corresponding relay r ¹ , r ³ etc. and at the opposite end of its control circuit ^{another display relay rr 1} , rr ³ etc. Each of these display ^{relays r 1} , r ³ etc. monitors a display device e ¹ , e ^a etc., shown here as electric lamps, and the relays rr ¹ , rr ^a etc. similarly monitor display devices ee ¹ , ee ³ etc.

The pole changing device Q, the push button contacts U ¹ , U ² , etc. and the time release devices J ¹ , / ⁵ , etc. can be at any central point, such as. B. in a signal box, grouped together, the display devices d, e ¹ , e ³ , etc. and ee ¹ , ee ³ , etc. are so that they. can be conveniently operated by the signalman, who has to operate the devices Q, J ¹ , J ⁵ etc. and the push button contacts U ¹ , U ^{2 etc.}

In the drawing are the contacts that are made by the various relays or by the Time release devices are operated, each by a number with the addition of the reference number of the relay or the device which the contact is actuated denotes. The operation of the above in general described device is the following:

As shown in the drawing, all parts are in their normal position, ie the delay relays I ¹ , 1 ³ etc. are de-energized, the pole changer Q is in its normal position, and all track sections are free. If the delay relays are de-energized, the signal relays R ¹ , R ² etc. are also de-energized, and therefore every signal points to halt. If these relays are de-energized and one of the access track relays T ¹ , T ³ , Γ ⁴ , Γ ^{6 is} energized, the associated access ^{blocking relay P 1} , P ³ , P ⁵ , P ^{6 is} energized. The circuit for the relay P ¹ goes, for example, from the terminal B of a current source, not shown, through the contacts 4 ^Äa , 5 ^Ä1 , 6 ⁿ , j ^Tl and the winding of the relay P ¹ to the terminal 0 of the current source. The delay circuit for relay P ¹ is also closed and contains the same path to contact 6 ⁷¹ , from there it goes through contact 10 of relay P ¹ and the winding of relay P ¹ to terminal 0. Device Q is in its normal position and the relay T * and T ⁵ and the corresponding drive relay energized, the switch relay m is energized in the normal direction by its normal working circuit which, from the terminal B by the contact 30 of the device Q, the contact 31 of the relay T ² the contact 32 of the relay T ⁵ , the contacts 33 ^De , 34 ^P5 , 35 ^Pl , 36 ^P3 , the winding of the relay m, the contacts 3j ^P3 , 38 ^Pl , 39 ^, 4O ^P6 , 41 of the relay Γ ⁵ , 42 des Relay T ² and 43 of device Q leads to terminal O. If relay m is energized in the normal direction, the switches W ¹ and W ^{2 are} in their normal position, and therefore the relay K is then energized in the normal direction.

It is now assumed that the signalman wishes to release ^{the signal S 1} for traffic on track Y from A via C. He expresses this, click the button contact U ^1, whereby the Working Group for relay J ¹ of the terminal B through contact U ¹ and the coil of the relay! ¹ to terminal O is closed. When excited, relay J ¹ closes its delay circuit from terminal B through pushbutton contact U ² , contact 48 ^T2 , contact 49 of relay I ¹ and the winding of relay I ¹ to terminal O. Relay I ¹ opens at its excitation at its contact 6 ¹¹ the working and delay circuits for the relays P ^1, and includes the working circuit for the relay R ¹ of the terminal B by the winding of the relay rr ^2, the contacts 54 ^{P3, 55/3,} 56, and 57 of the Relay K, 58 ^Λ , the break point of contact 5g ¹¹ , contact 6o ^T2 , the winding of relay r ¹ , contacts 61 ^, 62 ^Ts , 63 of relay R ² , the winding of relay R ¹ and contacts βή. ¹¹ , 65 and 66 of the relay K and Ö7 ^{/ 3} to the terminal O. The relay R ¹ is therefore energized and causes the arm of the signal S ¹ in its driving position with the aid of its actuating circuit from the terminal B through the contact 86 of the relay R ¹ and the actuator of the signal S ^{1 is brought} to terminal O. The relay R ¹ opens its contact 5 ^{Rl when it is energized} in the working and delay ^{circuits for the relay P 1} , which, since it is already de-energized by the opening of the contact 6 ¹¹ , already the normal working circuit for the relay m on its working contacts 35 ^Pl and 38 ^{Pl has} opened. The normal delay circuit for the relay m is then closed by the breakpoints of the contacts 35 ^Pl and 38 ^Pl and goes from the terminal B through the winding of the relay i, the normal closed contact 44 of the relay m, - the breakpoints of the contact

tes 35 ^Pl , the contact 36 ^P3 , the winding of the relay m, the contact 3j ^Ps , the break point of the contact 38 ^Pl and the normal closed contact 45 of the relay m to the terminal 0.

Since the relay i is now energized, it causes ■ the lighting of the indicator lamp ^ through its circuit from terminal B through contact 92 of relay i and lamp d to terminal 0. As a result of the closure of the circuit for relay R ¹ the relays r ¹ and W ^{2 are} energized, and therefore the lamp e ¹ is lit by its circuit from the terminal B through the contact 94 of the relay r ¹ and the lamp e ¹ to the terminal 0. Since the relay rr ^{2 is} energized ^{is, the lamp ee 2} is also made to light up by the closure of its circuit from the terminal B through the contact 100 of the relay rr ² and the lamp ee ² to terminal 0 to light.

If a train approaches the signal S ¹ and then enters the section AC and thereby energizes the relay Γ ² , the relay I ^{1 is} de-energized as a result of the openings in the contact 48 ^T2. The relay R ¹ is therefore de-energized due to the opening of the contacts 59 ^J1 and 64 ¹¹ , and therefore the signal S ¹ returns to its stop position. Since the circuit for relay R ^{1 is} open, relays r ¹ and w ^{a are} de-energized and thereby cause lamps e ¹ and ee ^{2 to be} extinguished. When the train enters section AC , relay P ^{1 is} again energized by its working circuit, which is the same as the one previously indicated, except that it contains contact 8 ^T2 instead of contact j ^T1 . If the relay P ^{1 is} energized, then a second normal closed delay circuit for the relay m from the terminal B through the winding of the relay i, the normally closed contact 44 of the relay m, the break point of the contact 31 of the relay T ² , the Contact 32 of relay T ⁵ , contacts 33 ^Pe , 34 ^P5 . 35 ^Pl > 3Ö ^P3 »the winding of the relay m, the contacts 37 ^P3 , 38 ^Pl , 39 ^Ps , 4o ^P6 , the contact 41 of the relay T ⁵ , the break point of the contact 42 of the relay Γ ² and the normally closed contact 45 des Relay m to terminal O closed. If the train leaves the section AC, the relay m is re-energized by its normal closed working circuit, as has already been indicated. The relay i is therefore de-energized and the lamp d goes out. After the train has left section aA , the working group for the act η ^Τι in the

before "Re'ais P s by the _scllloSS Cont. ¹ · _t It manner indicated again _n g ^e Achdé clear from <IEM foregoing that, ^ _ s ^m a train in the easterly direction A i ^{c +} t hnt CD leaves, all devices will be like the normal position without any

an activity has been carried out by the signal attendant after he had closed the push-button contact U ¹ in order to bring the signal S ¹ into the driving position.

It is now assumed that when all parts of the device are again in their normal position, the signal attendant in turn ^{releases the signal S 1} by depressing the push-button contact U ¹ in the manner previously described. If, after the arm of signal S ¹ has moved into the driving position, the signal attendant should wish to ^{bring the arm of signal S 1} in ^{1 back to} the stop position before a train has entered section aA , he will press the push-button contact U ^% and thereby interrupt the delay circuit for relay I ¹ and de-energize relay I ^1. The relay I ¹ deenergized in this way interrupts the circuit for the relay R ¹ and thus causes the arm of the signal S ¹ to return to the stop position. The relay P ¹ is then re-energized by its working circuit through contact j ^Tl in the manner already described. 8g

It is then assumed that all parts have been returned to their normal position and the signal attendant has again depressed the pushbutton contact U ¹ so that the signal S ¹ indicates the journey, and that, after a train has entered section aA , he has his arm of the signal S ^{1 returned} to its stop position and ^{wishes to release the signal S 3} for a train moving in the opposite direction. As a result, he depresses the push-button contact C / ² and thus interrupts the delay circuit for the relay I ¹ , which, after it is de-energized, de-energizes the relay R ¹ and thus causes the signal arm S ¹ to be returned to the stop position. The relay P ¹ , which was de-energized when the relay I ¹ previously opened its contact 6 ⁿ , now remains de-energized because the train occupying the section aA causes the contact j ^{Tl to be kept open.}

In order to release the signal S ³ , the signal attendant must then initiate the actuation of the time release device J ^1. At the beginning of this actuation, the contact 58 ^jl in the circuit for the relay R ^{3 is} open, and after a measured period of time, the contact 9 of the tripping device J ¹ closes, and a working circuit for the relay P ^{1 is} closed, which of the is the same as the first specified working circuit for the relay P ¹ , only that it contains the contact 9 of the trip device J ¹ in place of the contact J ^T1 . The relay P ¹ is so energized and closes its delay circuit in the manner described above, and the signalman then brings the trip device J ^{1 back} to its normal position and causes the

Contact 9 in the working group for the relay P ^{1 is} opened. The relay P ^1, however, remains excited by its delay circuit.

Now the signalman presses the pushbutton contact U ³ and causes the relay I ^{s to} be energized by its working circuit from terminal B through contact U ³ and the winding of relay J ³ to terminal 0 . With this excitation the relay P closes its delay circuit from the terminal B through the push button contact U ² , the contact 48 ^r2 , the contact 50 of the relay! ³ and the winding of relay I ^s to terminal 0. Relay J? ³ will now contacts rr from the terminal B through the coil of the relay ^3, 7g ^Pl, 59 ^n, 58 ^Λ, 57 and 56 of the relay K, the break point of contact ^55/3, the winding of the relay R ^3, the winding of relay R ³ , contact 67 ^is , contacts 66 and 65 of the

ao relay K and the break point of contact ^64/1 to terminal 0 energized. If the relay R ^{3 is} so energized, the signal S ^{3 is brought} into the driving position by its circuit from the terminal B through contact 89 of the relay R ³ and the mechanism of the signal S ³ to the terminal 0. When the relay J ³ is energized, it is a relay P ³ due to the opening of the contact I2 ^{/ 3-energized.} If relay P ^{3 is} deenergized, another delay circuit for relay m is closed by the breakpoints of contacts 36 ^P3 and 37 ^Pa . The relay i is therefore energized again and the lamp d lights up. The excitation of the circuit for the relay R ^{3 has the} effect that the working contacts of the relays r ³ and rr ^{3 are} closed and so the lighting circuits for the lamps e ³ and ee ^{3 are} closed.

If a train passes the signal S ³ and enters the section AC , the relay I ³ is de-excited by the opening of the contact 48 ^{7 ^.} If relay I ^{s is} de-energized, relays R ^s , r ³ and rr ^{3 are also} de-energized. The relay P ³ is now through its working circuit from the terminal B through the contacts

♦ 5 ii ^R3 , i2 ^{/ 3} , I5 ^T2 and the winding of relay P ³ to terminal 0 energized. The relay P ³ closes its delay circuit after its excitation, which contains its contact 16 in place of the contact 15 ⁷ * ² in the circuit just given. If the relays r ³ and rr ^{3 are} deenergized, the lamps e ³ and ee ^{3 are} extinguished again. If all sections are unoccupied again, all devices will be in their normal position again without any action on the part of the signal attendant having to take place after he had closed the pushbutton contact U ^3.

It is now assumed that all parts are in their normal position again, the only difference being that the section CD is occupied and thus causes relay T ^{3 to be} de-energized. It is also assumed that the signal attendant tries to ^{release the signal S 1} by closing the push-button contact U ^1. The relay I ¹ is then excited in the manner already described in that it closes ^{its normally open contact 59 / x;} but the circuit for relay R ¹ is still open at contact 62 ^T3 , which is operated by relay T ^s . The relay R ² is therefore excited by its circuit, which follows the route previously indicated for the relay R ¹ to the contact 6i ^K and from there through the break point of the contact 62 ^Ts , the contact 78 of the relay R ¹ , the winding of the relay R ² and the contacts 64. ^11, 65 and 66 of the relay K and ^67/3 supplies to the terminal 0th The thus energized relay R ² causes the arm of signal S ^{2 to be} in the call position through the circuit going from terminal B through contact 87 of relay R ² and the mechanism of signal S ² to terminal O. When passing through the signal S ² and entering the section AC, a train causes the relay J ¹ to be de-energized in the manner already described. Then the relay R ^{2 is} de-energized and causes the signal S ^{2 to} be the stop display again. If all track sections are free again, then all devices are again in their normal position without any action on the part of the signal attendant after he had closed the push-button contact U ^1.

It is now assumed that while all parts are in their normal position again, the signalman wishes to send a train from track Y to track Z via connecting track X. In order to flip the switches W ¹ and W ² , he moves the device Q into its changeover position and thereby causes current of opposite polarity to be fed to the relay m through the reversal points of the contacts 30 and 43 of the device Q. The relay m consequently closes its reversing pole contacts and this causes the switches W ¹ and W ^{2 to} move into their opposite or reversed positions under the action of their reversing circuit which includes the contact 46 and the reversing contact 47 of the relay m . If the switches W ¹ and W ^{2 are brought} into their opposite position, the relay K is energized in the opposite direction.

The signal attendant now depresses the push button contact U ¹ and causes relay I ¹ to be energized in the manner already described and a second circuit for relay R ² from terminal B through the winding of relay rr ¹ , contacts 68 ^PS , Ö9 ^{/ 5,} 7ο · ^75, the normally open contact 71 and the Umwendkontakte 72 and 56 of the relay K, the contact 57 of the relay K, the contacts 58 ^Λ, 5g ^11, 6o ^T2,

the winding of the relay r ¹ , the reversing contact 61 ^, the contact 78 of the relay R ^1, the winding of the relay R ² , the contact 64 ¹¹ the normally open contact 65 and the reversing contacts 66 and 75 of the relay K, the contact 76 of the relay K and contact 77 ^{/ B} to terminal O is closed. The actuating circuit for the signal S ^a is then at contact 87 of the relay i? ^a closed, and the arm of signal S ² therefore moves to the drive position. The circuit just described for relay I? Energy supplied to ² also energizes relays rr ¹ and r ^x and causes lamps es ¹ and e ^{1 to} be lit by their circuits which lead through contacts 98 and 94, respectively.

After the train has driven over the connecting rail X and all track sections are free again, all parts of the device with the exception of those for monitoring, displaying and operating the switches W ¹ and W ^{2 are returned} to their normal position without further activity by the signal attendant. In order to return the switches W ¹ and W ² to the normal position, the signalman must return the device Q to its normal position and thereby cause the supply of a current of normal polarity to the circuit for the relay m anew. By thus energizing relay m in the normal direction, it causes switches W ¹ and W ² to be returned to their normal position, and relay K is then energized in the normal direction. If the switches W ¹ and W ^{2 are} returned to the normal position in the manner described above, it is not necessary for the signalman to wait to operate the device Q until the train has moved out of sections AC and FG ; because one of the delay circuits for the relay m through the reversing contacts 44 and 45 of the relay m will prevent a change in the direction of excitation of the relay m as long as the train is in one of these sections. As soon as the train has left these sections, the change in the direction of energization of the relay m will be effected without further action by the signalman after he has returned the device Q to its normal position.

It should now be assumed that all parts have returned to their normal position, that the signal attendant has switched the switches W ¹ and W ² again and the signal S ² . 55 has released for a movement from track Y to track Z via connecting track X. If, after a train has entered section aA , the signalman wants to let the train continue on route Y instead of leading it to track Z via the switched points W ¹ and W ^z , he will first press the push button contact U ² Depress and thereby cause the relay I ^{1 to be} de-energized. When de-energized, the relay P- has the effect that the relay R ^{2 is} also de-energized. In order to close a working circuit for the relay P ¹ , the signal attendant will now operate the time release device J ¹ in the manner described above. When the relay P ^{1 is} energized, the signal attendant can close the normal working circuit for the relay m by returning the device Q to its normal position. The switches W ¹ and W ² are then returned to their normal position in the manner previously described. Now the signal attendant will close the push-button contact U ¹ and thereby cause the relay I ¹ and also the relay R ^{1 to be} energized and the signal S ^{1 to come} into the driving position.

From the previous description of a few typical traffic cases, the Operation of the device according to the invention for all other possible traffic cases can be easily understood.

From the foregoing description and the accompanying drawing it is clear that the device according to the invention means for remote control and remote monitoring of the Contains switches and signals from non-interlocked, manually operated devices, which can be of a very simple design, such as B. as an ordinary push button switch can be formed. It will also be seen that after a signal is below the Monitoring or regulation by pressing one of these push-button switches in his driving position is brought, a passing this signal and then train releasing all associated track sections the facility without further activity returns to normal on the part of the signalman.

Although only one form of multiple monitor in accordance with the invention is described and illustrated, it is evident that various changes can be made without sacrificing essence deviate from the invention.

Claims (6)

Patent claims: i. Arrangement for remote control and remote monitoring of railway switches and signals depending on the traffic conditions at which for each to monitoring device a usually open, manually operated switching device at a central monitoring point is arranged and the brief closure of this switching device the continued excitation of a Control relay causes the changeover the controlled device and this is then monitored until the train ride or a corresponding process is completed and the system is then returned to its ur-S initial situation, characterized in that a further, usually closed switching device with actuation located in the circuit of the control relay is provided by hand, which allows a changeover movement that has already been initiated to take back, provided that the traffic or operating conditions permit. 2. Device according to claim i, characterized in that the momentary closure of a (z. B. Z7 ¹⁾ of the switching contacts, the initial excitation causes a delay relay (J ^1), which then is kept in the excitation and the excitation other of a relay (R ¹ ) causes the device to be controlled (e.g. S ¹ ) to be monitored directly by a circuit that monitors the contacts of two auxiliary relays (R ² , K) that control the other devices, this circuit in turn by rail relays (Γ ² , Γ ³ ) is monitored. 3. Apparatus according to claim 2, characterized in that ^{a second circuit is closed via the armature of each delay relay (J 1} , J ³ , J ⁰ ) which contains the manually operated switching contact (U ² ) , which is closed in the idle state, by its Opening the actuation of the controlled device (S ¹ ) can be reversed. 4. Apparatus according to claim 2, characterized in that an access ^{lock relay (P 1} ) is provided for each signal (S ¹ ) which is only excited when the corresponding signal (S ¹ ) is on "stop" and only after de-excitation is re-excited by restoring the signal (S ¹ ) to "halt" and under certain traffic conditions. 5. Apparatus according to claim 4, characterized in that the actuation of the switches (W ¹ , W ² ) is initiated by a polarized relay (m) , the excitation circuit of this relay from the excitation of the associated Zulabrtsperrelais (P ¹ , P ^3, etc.) .) and track relay (T ² , T ⁵ ) is dependent, so that the movement of the points is prevented under unauthorized traffic or signal conditions. 6. The device according to claim 2, characterized in that display devices (e ¹ , e ³ , etc.) are provided by monitoring relays (r ¹ , r ² , etc.) whose excitation windings in the excitation circuit of the corresponding signal relay (R ¹ , R ^s ) are switched on, controlled. 1 sheet of drawings