DE1530407B2 - Monitoring device for alternating current circuits of the light signals in railway systems - Google Patents

Description

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The invention relates to a monitoring device signal lamp is only half the necessary device for AC circuits of the light signals in voltage).
Railway systems with variable operating voltages, in which, depending on the operating conditions, these requirements placed on a monitoring device for luminous flux via current transformer faults in the light signals can no longer be displayed signal circuits. with simple relay circuits, because the monitoring of the light signals in the monitoring currents often only slightly different To be careful, to avoid dangerous signal patterns in good time. Relays of this kind are very difficult to manufacture and avoid. For example, operating voltages for the lamps that are variable in terms of safety will not and cannot meet all safety requirements.

of railway light signals to which a lower voltage is applied at night than during the day in order to avoid the dimensioning difficulties, in a known monitoring device for changeovers, fed via a current transformer in order to dazzle the drivers in the dark. Electric circuits (German patent specification 1117151) a The so-called day or night operating voltage current transformer core used from a material, genes also fluctuate within a permissible tolerance - its permeability up to a limit value of the range, which can be for example + 10%>. Field strength is as small as possible and when it is exceeded, different setting distances must furthermore increase this limit value within a narrow field, ie distances between the feed point, the strength range steeply to its maximum value in most cases in the relay room. The dimensioning of the current transformer and the interlocking is located and from which by means of the monitoring device the dependencies of the men are then carried out in such a way that at the lowest operating voltage of the signal states in the rest of the interlocking system, primary operating current will carry the core into the area , and the signal location take into account the steep increase in permeability and are magnetized. This location distance can, for example, be triggered by the monitoring device connected to the secondary side of the converter, practically between the value zero and 6.5 km. Swaying further. For these reasons, the light is operated in the circuit of the monitoring relay signals with alternating current, which technically and economically simply allows an amplifier working as an electronic switch to be switched, the control input of which is connected to the secondary of the maximum permissible operating voltages er side of the current transformer is connected.
Required power from the feed point to the This monitoring device has the disadvantage of transmitting the signal location and at the signal location the fact that monitoring of the AC circuits for operating voltage for the corresponding lamp voltage is not possible due to wire contact. voltage to be reduced by means of transformers. This disadvantage is made possible by another known operating voltage and monitoring device (German patent specification, the peculiarity of the signal circuit is possible), which is based on the same principle, that the operational signal lamp current can be avoided by connecting a second current transformer to the The same core material as described above can be used as the remainder in the event of a fault. This second current transformer is with its pristrom. For example, the residual current caused by a faulty winding in series with the primary winding can then be the size of the normal first converter and the secondary windings of both signal lamp currents at night voltage converters are connected to one another. The ratio when there is an interruption on the primary 45 nis of the number of turns and / or the transverse side of the core of the lamp transformer at the signal location cuts the two transducers is dimensioned so that and a large distance between the points with correspondingly the maximum permeability in the core of the first large cable capacitance is available. . The above example shows that the permeability increase begins at an over-second converter Wall with such a tight tolerance is increased by the safety requirements for the following and the setting of the device to the earth faults: Required monitoring currents difficult and un-

Lamp filament is burnt out; 'Economically, but can furthermore also _{"iri, T,} -, 55 not all required security conditions ge-short circuit of the lamp transformer on the _{right are} * _{Thus, for} _ _{ß since yon both converters}

Pnmar side, because at night voltage and large _{dn and the same current flow through} one

Control distance the line fuse mcht _{Stö by Fre S} md pannungseinfall that only

can address more; _{a different} phase position compared to the

_{External voltage incidence of the} same and different 6o normal operating currents cannot be detected

licher phase to the operating voltage, for example.

example at night in conduction contact by T _he invention, the object is based on the tension in the size of the Tagspannung; desired safety requirements for with alternating interference voltage incidence of direct current; _{Light signals fed from the power supply can be filled} with a simple and different power consumption, which is greater than or less economical monitoring device than the permissible tolerance.

based on the nominal power of the signal lamp This object is achieved according to the invention

corresponding operating state (e.g. solved on the fact that the voltage on the secondary winding of the current

³ .4

converter occurring at normal operating current corresponding to the greatest point distance changes

Voltage as a function of the phase angle of the current. Due to the non-linear

drive voltage derived anti-phase partial voltage components, the operating current is no longer sinusoidal

voltage is almost compensated and that the voltage is shaped, and the secondary voltage of the current

one half-wave of this differential voltage across the 5 converter is distorted.

one with the one connection of the secondary winding The monitoring device can be in an already

of the current transformer connected diode with an existing switching device group, in which the for the

downstream capacitor, the switching means required with its other corresponding light signal

ren connection to the second connection of the seconds as well as the switching means for the dependencies in the

the winding is connected, the base of an interlocking system are arranged, be built in,

predetermined response value set Transi- This group is interchangeable and must be used for each

stors, in whose collector circuit the display digit distance is suitable without further setting

Switching means is arranged to be supplied while.

the voltage of the other half-waves through this condition, the monitoring

second, directly parallel to the secondary winding 15 devices not optimally on the case by case

of the current transformer switched diode short-circuited- local operating current can be set so that

will sen. due to the different distance and the

Since the curve shape of the operating current is due to the permissible tolerances in the components of the external

Components such as lamp filament, lamp transformer, system, due to the secondary winding

deviates from the ideal sinusoidal shape and with larger 20 of the current transformer depending on the normal

Distances the phase position between the operating and operating current occurring voltage, not complete

voltage and operating current deviate significantly.

can and thus a complete compensation of the emitter potential of the downstream Tran sistors T, e.g. B. npn silicon transistor, with the Zenerder invention to set the predetermined diode Z raised. The Zener diode is biased above the response value of the transistor in the emitter resistor R 4, so that a defined circuit is a Zener diode and parallel to the voltage for switching the transistor emitter terminal and the collector with in series _{30 is} given. The diode D1 acts as a load-switched display switching means, a resistor, and cuts the negative half-waves in an orderly manner. the compensated voltage. She prevents that

In order to reduce tolerances of the individual components in the over- the capacitor C 1 over the diode D 2

To be able to compensate for the monitoring device, the peak value is due to interference peaks, which also

Advantageously, "manner are provided in parallel with the control circuit of the 35 _m i operating situation on the line and

Transistor switched a variable resistor, via which current transformers are transmitted, wrongly

the one with its one connection between the base. being charged. The DC voltage at the base

of the transistor and the upstream diode connected to the transistor T can with the potentiometer R 2

is arranged. be set so that they are in the most unfavorable

One embodiment of the invention is smaller in the case of operation than that applied to the emitter

Drawing shown and is in the following in more detail voltage. The transistor T is blocked and

described. '. the relay Λ in the collector circuit has dropped out.

In the upper part of the drawing is the protection of the diode D 3 and the capacitor C 2

Feed point of the light signal arranged over the transistor in front of induction peaks of the display

monitoring device shown. Via the line 45 relay A. Also via the direct current supply + ■■

towards L the signal lamp SL is over the transfer and - induction peaks can also occur,

mator Tr at the signal location with the required material which could destroy the transistor. To this

operating current _to avoid overall from the voltage source N and P, is a surge element, consisting of the

feeds. Resistor R 3 and the capacitor C 3, before

See through the primary winding of the W 50 current transformer.

the operating alternating current flows, which is approximately Furthermore, terminals 1 and 2 are provided on the primary winding of the current proportional to the applied day and night voltage converter W. In the secondary winding, a voltage is induced to which the monitoring device differs, which is rotated 180 ° from the supply voltage by the operating currents supplied to the light signals. This voltage is determined by a lamp power and signal aspects attached partial voltage across the resistor R 1 (this can be adjusted. This ensures that the counter voltage set from one or a combination of variable in the factory across the borrowed resistors or a Transmitter be resistance R 1 and which stand through the resistor R 2 ), which is connected to the operating voltage, a fixed size of the control voltage at the base B sen, compensated. The current transformer has a very small voltage drop on the 60 of the transistor T, unchanged for the various primary sides. The operating cases can be used and the on-resistor R 1 is designed with high resistance so that the speech sensitivity of the monitoring device's power consumption is low. preserved.

This arrangement can cause external voltages. In the example shown, the display

with a different phase position or different frequency 65 switching means from a relay A, which in the event of malfunctions

can be detected. in the light signal circuit to be monitored

Due to the variable cable capacitance of practical pulls and the one corresponding to the normal value

table the value zero up to a maximum value ent- operating current remains in the dropped state.

However, the monitoring device can also be designed so that the transistor T on a Reverse stage acts. As a result, the indicator relay pulls when the associated signal lamp circuit is switched on on and drops off in the event of a fault. The circuit shown in the drawing can can also be modified so that instead of the separate direct current source +, - to feed the Indicating circuit the required direct current from the alternating current source for the signal lamps is produced. The primary winding of the current transformer can also be divided into the two wires of the signal lamp circuit to be ordered.

The following examples illustrate the function of the monitoring device shown in the drawing explained in more detail:

In normal operation, the control voltage applied to the base B of the transistor T is lower than the voltage existing through the Zener diode Z at the emitter E , since the voltage generated by the operating current in the secondary winding of the current transformer depends on the antiphase partial voltage set via the resistor R 1 is almost compensated for by the size of the operating voltage. The display relay on collector K has dropped out.

If the filament of a monitored signal lamp burns out, the current flowing through the primary winding of the current transformer W becomes smaller and the antiphase partial voltage across the resistor R 1 predominates. As a result, the control voltage at the base of the transistor T exceeds the size of the emitter voltage, the transistor is switched through, the relay A picks up, and the monitoring device issues a fault message.

If a short circuit occurs between the lines L , the operating current flowing through the current transformer increases and the voltage induced in the secondary winding of the transformer is greater than the counter voltage derived from the operating voltage. The transistor T is switched through and the device issues a fault message.

When one of the lines L is interrupted in the vicinity of the signal lamp transformer Tr , a current flows through the current transformer W , the magnitude of which is influenced, depending on the line capacitance, out of phase with the counter-voltage, which remains constant in its phase. The greater the residual current, the greater the phase difference between the voltages comparing on the secondary side of the converter, so that these voltages generate a control voltage corresponding to their phase difference at the base B of the transistor T which is greater than the voltage applied to the emitter E. is. The transistor is switched through and the monitoring device issues a fault message. In the same way, a fault message is given if an external voltage with the same frequency, but a different phase relation to the operating voltage, is present on the line L between the converter W and the signal transformer Tr.

The security requirements listed above are met by the monitoring device for everyone Faults in AC circuits of the light signals met in the manner described above.

Claims (3)

Patent claims: 1. Monitoring device for alternating current circuits of the light signals in railway systems with variable operating voltages, in which, depending on the operating current, faults in the light signal circuits are displayed via current transformers, characterized in that the voltage occurring on the secondary winding of the current transformer (W) with normal operating current is dependent is almost compensated by an anti-phase partial voltage derived from the operating voltage (e.g. via the resistor R 1) and that the voltage of one half-cycle of this differential voltage via a diode (D 2) connected to one terminal of the secondary winding of the current transformer (W) with a downstream capacitor (Cl), the other terminal of which is connected to the second terminal of the secondary winding, the base (B) of a transistor (T) set to a predetermined response value, in whose collector circuit the display switching means (e.g. a relay A) is arranged, is supplied,. while the voltage of the other half-waves is short-circuited via a second diode (D 1) connected directly in parallel to the secondary winding of the current transformer (W). 2. Monitoring device according to claim 1, characterized in that for setting the predetermined response value of the transistor (T) in the emitter circuit a Zener diode (Z) and parallel to the emitter connection (E) and the collector (K) with a series-connected display switching means (A) a resistor (R4) is arranged. 3. Monitoring device according to claim 1 and 2, characterized in that a variable resistor (R ^{2) is connected in parallel 1} to the control circuit of the transistor (T), which has one connection between the base (B) of the transistor and the upstream diode ( D 2) is arranged. 1 sheet of drawings