DE3043661A1 - INSTALLATION AT AN ELECTRONIC ACTUATOR FOR THE FEEDING AND REMOTE MONITORING OF POINT DRIVES - Google Patents

Abstract

1. A device in an electronic setting mechanism for feeding and remotely controlling switch drives (A) operated by a three-phase current fed via four lines (L1-L4) with limit position contacts (AK1-AK4) arranged in the star point connections of the motor windings (W1, W2, W3) and controlled by the drive, by which the motor windings can be connected to the three-phase mains when closing connecting contacts (WSS/1-WSS/4) and by which a monitoring circuit is closed across the four lines and the three windings (W1-W3) of the drive for a d.c. voltage-fed switch monitoring unit, after the rotation of the drive to reach the respective new limit position where the motor windings are asymmetrically fed at least during run-down, but are symmetrically fed during the rotating phase, and wherein is arranged a monitoring unit (Ü4) controlled by the setting current, which resets a control switch (WSS) for the connecting contacts (WSS/1-WSS/4) in the case of the setting current which flows in the rundown phase, set during the introduction of a reversing operation, characterised in that the monitoring unit (Ü4) is designed as a switch (K1 in Figure 7) inserted into the central conductor (L4) of the supply circuit and in its currentless state during the rotating phase of the drive causes a control signal (e) to be emitted for connecting a further switch (K2) connected parallel to the first switch (K1), and that upon its response during the run-down phase the further switch (K2) resets the previously set control switch (WSS) and cancels the control signal.

Description

SIEMENS AKTIENGESELLSCHAFT Our hallmark Berlin and Munich VPA 80 P 2 6 3 8 DE

Equipment in an electronic signal box for feeding and remote monitoring of point machines

The invention relates to a device in an electronic signal box for feeding and remote monitoring from three-phase driven via four lines Turnout drives with arranged in the star point connections of the motor windings, controlled by the drive Contacts via which the motor windings are connected to the three-phase network when the connection contacts are closed can be switched on and via which after the drive has revolved and the new one has been reached End position a monitoring circuit routed via the four cables and the three windings of the drive for a DC-powered switch monitor closes, the motor windings at least during are fed asymmetrically during the run-out, but symmetrically during the rotation.

Such a device is known from DE-PS 977 164, for example. It has proven itself in practice and is in principle still used today. The switching means for controlling and monitoring are implemented using relay technology. The safety required in the railway industry is achieved on the one hand by the technical interdependencies between the control, actuating and monitoring switching means of an interlocking-side control module for the relevant turnout, the so-called turnout group, and unrch the design of the EeIaIs _{0 used,} namely through positively driven contacts and g © g © b © a @ mfalls aae-Gi-6-Fa / 11/14/80

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mechanical support of the individual contact systems. Any malfunction of the switch or one of those intended for controlling, setting and monitoring the switch Components leads to a fault identification in the relevant turnout group. The fault identification takes place decentrally. It is caused by the fact that within the turnout group at least one the relay contacts provided there does not assume the position that it would in normal operating conditions or operating behavior, so that a functionally determined circuit, e.g. a monitoring circuit . does not come about.

With an electronic interlocking with its central logic, there are no decentralized dependency circuits needed. As a result, mechanically complex special relays are no longer required. Much more an electronic interlocking can be used as an interface between logic and performance electronic switching means anj, however, must be ensured by suitable measures that these switching devices work just as safely as the relays used in a decentralized control system.

Via the interface between the logic circuits of the electronic interlocking and the power range of a point machine, one Direction of positioning commands and in the other direction monitoring messages are transmitted. With everybody The control command is initially set by a phase changer, e.g. a relay, to determine the direction of travel of the drive selected and then switched through the mains voltage to the drive with a circuit breaker, e.g. a contactor. If this switch switches at an inopportune time, a corresponding message must be issued immediately.

The monitoring also has the end position over-

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monitoring and testing of all four adjusting cores leading to the drive. Furthermore, both in Signaling as well as in command direction an absolute potential separation between logic and power range to ensure. During an adjustment process, it must be ensured that the drive is activated when the end position is reached turns off. If the end position is not reached, the drive should run after a maximum permissible running time be switched off.

A further development of the invention is intended to permit the marking of the respective switch position taken; another switch position should be the respective switch position of the phase changer in the monitoring process include, i.e. the respective monitoring result should make a comparison of the target and the actual position of the Include turnout drive.

The object of the present invention is therefore to provide a device according to the preamble of claim 1 to create specified type that meets this requirement.

This object is achieved in a device according to the preamble of claim 1 in that in the center conductor of the supply circuit is connected to a monitor controlled by the actuating current, via a downstream switching element is a control switch previously set when initiating a reversing process for the switch-on contacts resets if it is within a specified period of time since the beginning of the Reversal process changes from the unaffected to the influenced operating state. The given The period of time is determined by the longest expected cycle time of the drive.

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A preferred embodiment of the invention, in which the time for switching off a drive when Reaching the end position prepared by the control logic of the interlocking, but ultimately independent is from the program sequence within the logic, provides that in the center conductor of the supply circuit a from the control current controllable first switch is connected that the interlocking when the switch is de-energized a control signal for switching on a switch connected in parallel to the first switch during the rotation phase of the drive another switch triggers and that the other switch when responding to the previously resets the set control switch and that

Control signal clears.
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The reliability of a monitoring message and thus the security of the process control by a Electronic interlocking depends largely on the functionality of the decentralized monitoring modules away. In order to check the functionality of the monitoring modules almost continuously, after a advantageous embodiment of the invention provided, the monitoring circuit of the drive in the changeover breaks periodically to be disconnected for a short time and the messages issued by the supervisors to check for plausibility. According to a particularly advantageous development of the invention no separate switching means may be required for the function test of the monitors, but rather the the same switching means must be used as they are already available for controlling the drive.

The invention is described in more detail below with reference to an exemplary embodiment shown in the drawing explained.

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Figures 1 to 6 show the control and monitoring circuit a point machine in different operating phases together with the according to the invention provided monitoring switching means and from these issued surveillance mark; Figure 7 shows a preferred embodiment of the invention Device for feeding and monitoring a point machine.

In FIGS. 1 to 6, the control and monitoring circuits that are formed are shown in thick lines Lines have been highlighted.

In Figure 1, a point machine A is shown schematically, which is fed via four lines L1 to L4 and can be controlled and monitored from an interlocking. The drive has a three-phase motor with the Windings W1 to W3, which are connected in a known manner via end position contacts AK1 to AK4. As a power supply device A three-phase three-phase network with phases R is used to reverse the drive, S, T and the common neutral conductor Mp. In the outer conductors L1 to L3 and in the center conductor L4 Contacts WSS / 1 to 'WSS / 4 of a control switch (WSS in Figure 7), which is used to reverse the drive from one position to the other by the control switch be temporarily closed. Furthermore, contacts WLR / 1 are in or between two of the three outer conductors to WLR / 4 of a turnout direction selector, not shown switched over which the phase position of the currents flowing on the outer conductors L1 and L2 for the clockwise and anticlockwise rotation of the drive can be interchanged.

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In Figure 1 it is assumed that the point machine a occupies its two end positions. The motor windings are disconnected from the mains through contacts WSS / 1 to WSS / 4 separated. As long as these contacts are open, the other contacts WSS / 5 to WSS / 8 are on the control switch closed. They enable a monitoring circuit via the four feed lines and can form the three motor windings. There are several current-controlled monitors in the monitoring circuit Ü1 to Ü4 switched, the output data H (high), L (low) at their outputs A1 to A4 not feed illustrated control computer of the electronic interlocking, the state from these output data the relevant switch recognizes.

In order to keep the monitors free from disruptive driving current influences, the monitoring circuit is operated potential-free. A potential-free DC voltage source U _pR serves as the power supply for the monitoring circuit. In the assumed position of the drive, the monitoring circuit optically highlighted in FIG. 1 has formed. The monitoring current flowing in the process causes the monitors Ü1 and Ü2 to send the corresponding data to the downstream control computer (the monitor Ü4 is not influenced by the monitoring current; it responds during the start-up and run-down phases of the drive). The current-carrying state of the monitor Ü1 is used together with a monitoring identifier of one of the monitors Ü2 and Ü3 to identify the end position of the drive; Without this monitoring indicator, the current-carrying state of the monitor Ü1 signals a switch opening message. The de-energized state occurs due to operational reasons when converting the drive.

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The monitor Ü2 is used as a switch position monitor, for example for the positive position of the switch. With the assumed turnout position, the turnout position monitor Ü3 for the minus position of the turnout is short-circuited by a diode D3. In a corresponding manner, the switch position monitor Ü2 for the positive position of the switch is short-circuited by a diode D2 connected in parallel to its inputs when the drive adopts the other end position. From the data H, H, L, L that can be tapped off at terminals A1 to Ak , the control computer determines the position of the switch controlled by the drive according to a logic that is impressed on it, and stores a corresponding identifier in associated memory switching means for calling up and further processing as required.

In FIG. 2 it is assumed that the control computer outputs the control command for reversing the switch and so that the control switch has reversed. The contacts WSS / 1 to WSS / 8 assigned to the control switch then assume the position shown in FIG. The previously existing monitoring circuit by opening the contacts WSS / 5 to WSS / 8 and the supply circuit for the drive motor is interrupted closed by contacts WSS / 1 to WSS / 4. The winding W1 of the drive motor is on the Phase voltage, the windings W2 and W3 at the linked phase voltage between the phases S and T. The drive motor begins to rotate without first changing the end position contacts AK1 to AK4.

The one flowing through the center conductor L4 during the start-up phase Actuating current influences the monitor Ü4 provided according to the invention and thus leads to the fact that

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A corresponding H - at output A4 of the monitor Potential can be tapped. At the outputs A1 to A3 the monitor Ü1 to Ü3 is at this point in time L potential.

In Figure 3 it is assumed that the point machine rotates. In the start-up phase, those from the drive are mechanical controlled end position contacts AK2 and AK4 have been reversed. The motor windings are thus behind switched in star when the motor starts up. All four monitors Ü1 to Ü4 are unaffected? at her They provide outputs A1 to A4 to the downstream control computer L-potential.

In FIG. 4, the power supply circuits of the drive are in the run-down phase shortly before the drive motor is switched off highlighted. In this phase, the end position contacts controlled by the drive also have AK1 and AK3 changed and the star point connection of the motor windings was cut. The motor is now excited asymmetrically via the phase voltage and the linked phase voltage, with the Center conductor L4 a current flows for a short time, which influences the monitor Ü4. At exit A4 this Monitor is thus Η-potential, at the outputs A1 to A3 of the other monitored L-potential.

In the run-down phase of the drive, the one for reversing the drive will be explained in a manner still to be explained previously set control switches (WSS in Figure 7) are reset to the initial position. Change at the same time the contacts WSS / 1 to WSS / 8 controlled by it into the switching position shown in FIG. The contacts WSS / 1 to WSS / 4 interrupt the supply current

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circuit for the drive motor; contacts WSS / 5 to WSS / 8 enable the monitoring circuit to be formed as it is highlighted in FIG. At the new end position of the drive, the Point position monitor Ü3 for the minus position of the turnout acted upon during the point position monitor Ü2 remains unaffected for the plus position. At the outputs A1 and A3 of the monitors Ü1 and Ü3 is Η-potential, at the outputs A2 and A4 of the monitors Ü2 and Ü4 L-potential. From this data the control computer determines the new point position, which will be used for subsequent treatment of the associated track element stored in an allocated memory

will. The changeover process is now complete. 15th

In Figure 6 it is assumed that the switch was opened, i.e. from the blunt side against the was driven through the position defined by the last actuating order carried out. The two end Layer contacts AK1 and AK3 changed, which was the last to be actuated when reversing the switch to the minus position became. As a result of the contact change, the previously existing monitoring circuit was via the center conductor L4 and the outer conductor L2 are interrupted and the monitoring circuit optically highlighted in FIG. 6 closed. The monitoring current flowing now only influences the monitor Ü1, which is in the Interaction with the other unaffected monitoring devices Ü2 to Ü4 by switching on of the Η-potential on output A1 indicates the opening of the switch.

Figures 1 to 6 show where in the invention = essen facility for dining and remote monitoring

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Turnout drives are to be provided with monitors, which Purpose these monitors serve and what messages they give to a downstream control computer. the The technical training of the supervisors is of no importance in principle. As are particularly beneficial The monitors are designed as optocouplers because they enable absolute potential separation between the power circuit and the evaluation logic. Optocoupler However, they do not provide safety-related components which, in the event of a defect, must be expected to not work recognizably incorrectly. For this reason, in order to achieve the same level of security as with monitors implemented in relay technology it must be ensured that at least those monitors designed as optocouplers are working properly Functional behavior can be checked, the output signals of which indicate the correct operating state mark the drive.

A defect in an optocoupler can have two effects, namely first, the optocoupler is constantly, regardless of its input data, a signal at its output or it is no longer in the Able to send a signal. Only the first error can be dangerous because the downstream control computer only derives an indicator for a non-hazardous state from the Η-potential.

The test is done in that the optocoupler between the individual reversing phases of the point machine be reversed sporadically or preferably cyclically for a short time. In doing so, they have to do the job properly Change operating behavior to the other switching state. This change can be

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in the downstream control computer, which expediently also the commands for reversing the optocoupler monitor in a suitable manner. In this way there is a very short error disclosure time achievable, which gives the device according to the invention the same security as one Corresponding device implemented in relay technology.

In the end position of a point machine, two monitors are always effective, namely the end position monitor Ü1, over which the opening of a switch is to be determined, and one of the ones in series with it Monitor Ü2 and Ü3 for identifying the position of the point machine. For functional testing of the connected Supervisors have to switch them off temporarily. This can be done by applying control potential to the Input of a switch T1 take place. Until switch T1 is reopened, none of the monitors may be allowed lead to the output Η-potential assigned to it. If Η-potential can be tapped at one of the outputs during this time, the control computer recognizes this and causes the output of a fault message for the relevant switch. After opening of the switch T1, two of the three monitors in question must again have H-potential at their output so that the actuating computer work out a code for determining the end position of the drive can.

In the explanation of Figure k it was indicated that the response of the monitor Ü4 during the run-out phase is an indicator for reversing the control switch to disconnect the supply circuit

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for the motor windings is to be derived. Such a tax code could easily be done by the control computer form. However, the actual switch-off time is then determined by the finite processing time of the control computer for outputting the reversing command. To avoid this delay the control logic To be independent, provision is made according to the invention for the control switch to be reversed in terms of hardware realize. The device shown in FIG. 7 serves this purpose.

The one for connecting the supply voltage to the drive The required control switch WSS is usually de-energized. Has the control logic of the actuating computer If an actuating command is worked out, it influences a safe output circuit in a manner that is not specified for the command. This output circuit can be designed as a safe amplifier V, for example how it was developed for the railroad industry. The one occurring at the output of the output amplifier V. DC voltage is used as the supply voltage for the control switch WSS and via a voltage divider from a resistor R and a thyristor Th1 simultaneously as a control voltage for one in the supply circuit of the control switch located switch T2.

This switch has a low resistance when the thyristor is blocked, so that the control switch WSS respond and its Contacts can change into the position shown in Figure 2, in which this on the one hand the monitoring circuit interrupt and on the other hand close the supply circuit for the drive motor.

Usually flows during the start-up phase of the drive a supply current via the center conductor LA. In the secondary winding of a current transformer W

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a voltage built up, which after rectification in a full-wave rectifier G and smoothing on a Capacitor C temporarily sets a first switch K1. This switch is designed as an optocoupler, whose light-emitting diode is arranged parallel to the capacitor. For the duration of the start-up phase, that is the asymmetrical supply of the motor windings is usually the switching transistor of the optocoupler steered through; during the subsequent rotation phase of the drive, the switch is high-resistance in any case. He gives a tax code e to a subordinate Switching element E, which converts the tax code into a control signal that is pending for a longer period of time. This The control signal switches the transistor T1, which is responsible for the functional test of the monitor during the changeover breaks of the drive is provided. The transistor T1, which here has the function of an intermediate switch, controls another switch K2 from one position to the other. This switch is also designed as an optocoupler, the light-emitting diode being connected to the emitter-collector circuit of the transistor T1 is. The switching transistor of this optocoupler is in the control circuit of another optocoupler K3.

The activation of the further switch K2 initially has no effect on the switching state of the Control switch WSS because, according to the assumption, the intermediate switch T1 only after the end of the start-up phase of the Drive was controlled and at this time the supply circuit via the center conductor L4 has already been disconnected. However, if the run-down phase is reached after the drive has rotated, Current flows through the center conductor IA. The like-

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the reversing supply voltage for the switch K1 and K2 has the effect that the third optocoupler K3 now also becomes effective. The switching transistor of this optocoupler becomes conductive as soon as the threshold voltage of the associated light-emitting diode is reached and controls the downstream tyristor Th1 through. It changes the voltage drop across the resistor R in series with the thyristor Th1. This leads to blocking of switch T2 in the supply circuit of the control switch.

The control switch is de-energized as a result and controls its contacts again to those shown in FIG. 1 shown position in which they interrupt the supply circuit for the motor windings of the drive and the monitoring circuit via the four wires and close the three windings of the drive.

The actuating computer registers via the output signal of the first switch K1 that the run-down phase of the drive has been reached and then switches on At the end of the run-out phase, the intermediate switch T1 returns to the high-resistance state that it was before Had taken the beginning of the switch. In addition, the control computer switches the safe output amplifier V from and thus causes the shutdown of the supply voltage for the control switch WSS. The circuit is thus again in the starting position assumed in FIG. The device indicated in FIG. 7 enables the switch-off time in an electronic interlocking for driving a turnout with high precision and independent of the response time for data processing determine the necessary controls and perform the shutdown. The Transistor T1 advantageously designed several times

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uses, namely once during the changeover breaks briefly discard the monitors excited in the drive's monitoring circuit and thus carry out a functional test and on the other hand to switch off the control switch as soon as the drive is switched and has reached its new end position.

In the explanation of the device according to the invention it was tacitly assumed that a The point machine was switched over properly. If this is not the case, a drive achieves its through If a new end position is not specified for an actuating order, it must be ensured that the actuating circuit It is separated as soon as it is established that it obviously cannot reach its new end position. This is done by a timer not shown in the drawing, which is at the beginning of the Reversal process is set and the operational resetting of the for a predetermined period of time Control switch for the connection contacts allows and the failure of this switching process the Forced shutdown of the control switch brings about. For example, the one shown in FIG. 7 can be used for this purpose Output amplifier V can be used. If the drive reaches its new end position during a changeover process not within a specifiable minimum time, which is essentially due to the proper operating behavior the drive is given a certain maximum cycle time, the interlocking switches the safe Output amplifier V and thus interrupts the power supply for the control switch that is still switched on; this disconnects the supply circuit that is still closed for the drive concerned and the end position and point position monitoring

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Prepared to close the control switch break contacts.

The device according to the invention for feeding and remote monitoring of point machines does not only work then as intended, if a point machine is to be moved from one of its two end positions, but also when the drive has not reached its specified end position. This case can e.g. occur if there is a foreign body between the switch blades adjacent to the switch layer in question, e.g. gravel, is jammed. In this case, the start-up phase explained with reference to FIG Changeover process of the drive skipped and the drive motor is only excited symmetrically until the run-out phase is reached first switch K1 unaffected during the reversal process; it thus causes the control signal to be output e, which then disconnects the actuating circuit as intended in the run-down phase of the drive.

By including the contacts WSS / 5 to WSS / 8 controlled by the control switch in the monitoring circuit it is ensured that when a monitoring circuit is established, the supply circuit for the drive is interrupted in any case.

The correct operating behavior of the was not monitored in the illustrated embodiment Direction of travel selector whose contacts WLR / 1 to WLR / 4 determine the direction of travel of the drive. That Functional behavior of this selector can be checked in a simple manner by responding the monitor makes Ü2 and Ü3 for the point position identification dependent on the switching status of the Direction selector. The point position monitor Ü2

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for the plus position of the switch there is a closed contact of the running direction selector in the plus position of the switch to be connected in series or an open contact of the running direction selector to be connected in parallel.

The same applies to the switch position monitor for the negative position of the switch. He is an in Minus position of the switch closed contact of the running direction selector to connect in series · or an open one To connect the contact of this direction selector in parallel. These contacts can be those in the drawing Replace the diodes D2 and D3 connected in parallel with the monitors Ü2 and Ü3.

The functional behavior of the running direction selector can also be monitored by the fact that the monitor Ü1 a contact of the running direction selector is connected in series and this series connection is the series connection from a further monitor and an exclusion contact of the direction selector connected in parallel will. In one end position of the drive then speaks - as long as the direction selector is correct works - one of the monitors works, and the other at the other end position. This end position indicates the target end position of the drive specified by the actuating order carried out last in each case; the actual end position of the drive, which is given by the position of the drive contacts AK1 to AK4, is indicated by the monitors Ü2 and Ü3 are displayed for the point position identification. By comparing the monitors that are connected in each case, it can be seen whether the direction of travel Voter actually assumes the switching position specified by the last control order or not; Disruptions in the operating behavior of the running direction selector can be seen shortly after their occurrence. (Short error disclosure time; the error is recognized and can be remedied before a possibly occurring

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occurring other errors can occur and cause a malfunction of the drive).

14 claims
7 figures

Claims (14)

VPA 80 P 2 6 3 8 DE claims Set up at an electronic signal box "for feeding and remote monitoring of over four lines three-phase driven turnout drives with arranged in the star point connections of the motor windings, Contacts controlled by the drive, via which the motor windings when the connection contacts are closed can be connected to the three-phase network and via which, after the drive has revolved and reached of the new end position, one guided over the four cables and the three windings of the drive Monitoring circuit for a DC-powered switch monitor closes, whereby the motor windings asymmetrically at least during the run-out, but symmetrically during the rotation are fed, characterized in that in the center conductor (L4) of the feed circuit a monitor (Ü4) controlled by the actuating current is connected, which is connected via a downstream one for each Reversing process controllable switching element (E) a previously set when initiating a reversing process Control switch (WSS) for the connection contacts (WSS / 1 to WSS / 8) resets if it is within a predetermined period of time since the beginning of the reversal process from the uninfluenced to the influenced Operating status changes. 2. Device according to claim 1, characterized in that the predetermined period of time is determined by the operationally expected longest cycle time of the drive. 3 O / ι 3 6 6 VPA 80 P 2 6 3 8 DE 3. Device according to claim 1 and 2, characterized in that one of the center conductor (IA) of the supply circuit flowing actuating current controlled first switch (K1 in Figure 7) is provided is that due to its currentless state during the rotation phase of the drive, the output of a Control signal (e) for switching on a further switch connected in parallel to the first switch (K1) (K2) causes and that the further switch (K2) when it responds, the previously set control switch (WSS) resets and clears the control signal. 4. Device according to claim 3, characterized characterized in that the further switch (K2) consists of an optocoupler whose Switching transistor on a supply voltage given by the control voltage of the first switch (K1) and can be controlled by the associated light-emitting diode which can be switched on indirectly by the first switch (K1) is. 5. Device according to claim 4, characterized in that that in the control circuit of the control switch (WSS) an additional switch (K2) controlled further optocoupler (K3) is provided. 6. Device according to claim 5, characterized in that the supply circuit of the Control switch (WSS) for the connection contacts, a switch (T2) is arranged, the control input of which at the tap of a voltage divider consisting of at least one resistor (R) and one from another optocoupler (K3) controllable switch (Th 1) and that VPA 80 P 2 6 3 8 DE the voltage divider is connected to the output voltage of an output amplifier (V) that can be activated by the interlocking when an actuating order is triggered until the drive is switched off.
5 7. Device according to claim 3, 4, 5 or 6, characterized in that for controlling the further switch (K2) one of the first switch (K1) controllable intermediate switch (T1) is provided, the power supply from which is provided for monitoring the drive DC voltage source (üp _R ) takes place. 8. Device according to claim 1, characterized in that g e that the two poles of the DC voltage source provided for monitoring the drive (Upft) to those two outer conductors (L1, L3) of the three-phase network (R, S, T) are connected, which are controlled by the drive End position contacts (AK4, AK1) are always decoupled and that in the monitoring circuit outside of the feed lines (L1 to IA) an end position monitor (Ü1) is switched. 9. Device according to claim 1, characterized in that that the over the end position contacts (AK4, AK3) with one of the other Outer conductor (L1, L3) connected outer conductor (L4) via monitors (Ü2, Ü3) responding to different current directions for the point position identification is connected to the center conductor (IA) of the three-phase network. 3C43661 VPA 80 P 2 6 3 8 DE 10. Device according to claim 9, characterized in that that the response of the monitors (Ü2, Ü3) for the point position identification depends is made by the switching state of a direction selector that can be reversed with each changeover process the relevant switch. 11. Device according to claim 1, characterized in that that two each other via exclusion contacts one of the direction of travel of the drive indicating the direction of travel selector, end position monitors (U1) connected in parallel are provided, their switching status the target operating state of the point machine indicates.
15th 12. Device according to claim 7 and 9 or 10 or 11, characterized in that via the end position monitor (Ü1) and one of the Point position monitor (e.g. Ü2) guided circuit in the changeover breaks of the drive (A) for test purposes is briefly separable. 13. Device according to claim 7 and 12, characterized characterized in that for the needs-based disconnection of the monitoring circuit for test purposes the intermediate switch (T1) is used. 14. Device according to claim 8, characterized in that the sole response of the end position monitor (Ü1) a switch approach message causes.