DE2155841A1 - Electrical system for vehicles - Google Patents

Description

PATENT LAWYERS

DlPL-INQ. DR. IUR. DIPL.-ΙΝΘ.

VOLKER BUSSE DIETRICH BUSSE

45 Osnabrück, November 9, 1971

MOSERSTRASSE 2O / 24 DB / Ka

BRITISH LEYLAND TRUCK & BUS DIVISION LIMITED , Leyland, Lancashire, England and BUTEC LIMITED , Cleveland Road, Leyland, Lancashire, England

Electrical system for vehicles

The invention relates to electrical systems for vehicles and is concerned with the creation of modular ones Electronic systems for many of the requirements for function control and safety precautions that occur in vehicles and power control.

Electrical systems for vehicles include, in particular, devices for generating, transmitting and storing electricity, starting and possibly ignition devices, Lighting devices, windscreen wiper and fan drives, as well as instruments and control devices.

The system according to the invention is now primarily characterized by means of logic elements to determine changes in or failure of the operation of the system or

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for controlling the power supply of parts thereof. Preferably the logic gates consist of pest body circuits.

In a further embodiment of the invention, the system is characterized by

a) one or more output converters for playback or display the condition of the system, and

b) one or more linking elements for connecting the or each output converter to components of the electrical Equipment of drive motors, gears or brakes of a vehicle.

A preferred embodiment of the aforementioned embodiment of the

Invention is characterized in that at least one link from the from

a) a basic switching element that has an AND or an OR link as an output depending on the given inputs generated,

b) a level deforming or locking member, which at a vorbe A switching process is generated at the correct voltage level, and

c) an iron pulse generator switching element for generating output pulses over a range of time intervals, existing group is selected.

Furthermore, the electrical system according to the invention is thereby

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characterized in that it comprises one or more of the following electronic blocks:

1) an alarm block with at least one basic switching element, which as a function of a given input to this as Output generates an AND or an OR link,

2) a level block with at least one level switching element that initiates a switching process at a predetermined voltage level generated, wherein the block can be connected to input converter circuits responsive to vehicle operating states is,

3) a warning block with at least one basic switching element, pulse generator switching element or level switching element, the output of an AND or an OR link or such a combinatic generated by links that in response to a given input to the element a warning signal output occurs, and

4) a power block with one or more power supply elements for supplying parts of the electrical equipment of the vehicle, the output of the or each power supply element either through a basic switching element that generates an AND or an OR link as an output, or through a pulse generator switching element that a range of time intervals with a variable duty cycle is never generated, or is changed by a level switching element with the load.

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Several embodiments of the subject invention are provided explained in more detail in the following description in conjunction with the drawing, it shows:

Fig. 1 and 2 two versions of basic switching or logic elements, j

3 and 4 the members of FIGS. 1 and 2 in a circuit

as failure indicator,

Fig. 5a to 5d members of FIGS. 1 and 2 in circuits for

Creation of various exits,

6a to 9b members according to FIGS. 1 and 2 in circuits for

Creation of various linked outputs,

Fig. 10a, b and modified versions of the members according to 11a, b

Fig. 1 and 2,

Fig. 12a, b and link elements according to FIGS. 1 and 2 in one 13a, b

Circuit for controlling power transistors _s

14 and 15 show two versions of level switching elements, FIG. 16a to iodine elements according to FIG. I ¹ I and 15 in circuits for

Creation of various exits,

Fig. 17a, b and Gliedertiach Fig. 14 and 15 in circuits for I8a, b

Control of power transistors,

Fig. 19a, b and possible applications for links according to Fig. 20a, b

14 and 15,

21 and 22 show two versions of pulse generator switching elements FIGS. 23a, b and elements according to FIGS. 21 and 22 in circuits for 24a, b

Control of power transistors,

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Pig. 25a to links according to Pig. 21 and 22 in circuits 27b

for generating acoustic or optical

Impulses,

28a to 30 elements according to FIGS. 21 and 22 in circuits

to control the speed of motors,

Figure 31 is a general diagram of a linked plant for a motor vehicle, in which those described in connection with FIGS Links are combined in electronic blocks,

Fig. 32 to 3 ¹ * different versions of alarm blocks, j Fig. 35 a failure block,

36 shows a level determination block,

37 shows a warning block,
yy

Fig. 38 to 43 performance blocks in different scarfs

for various applications.

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The plant is designed so that only three types of basic members to create the numerous safety and power control punctures that occur in motor vehicles required are. The three links are a linking link, a level reshaping link and a timing link.

Link (Fig. 1 to 13)

This member is designed so that there is a wide range of logical or connecting punctures for the various Provides aspects of error detection and power control in motor vehicles.

It consists of two transistors, both of the PNP type (Pig. 1) or both of the NPN type (Fig. 2), along with the Necessary components to create both the required .Biasing current and a wide variety of fan input and Subject starting conditions.

The PNP version of the link according to FIG. 1 has two PNP transistors TrI. and Tr2, a bias circuit comprising a resistor R5 and a diode D4 (the diode D * l could be through a Resistor or a resistor together with a diode can be replaced either in series or in parallel), fan input parts with diodes Dl and D5 and resistors R 4 and R8, fan output parts with resistors Rl, R2 and R6 and diodes D2 and D3, as well as overload fuse resistors R3 and R7 (the

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Resistors R3 and R7 could be diodes or diodes together replaced with resistors either in series or in parallel).

j Diodes D2 and D3 create outputs for a positive

knot system. You could be more logical to the formation of 'negative' or linking outputs individually or together, vice versa; will. One or more of the diodes D2 and D3 or the reflectors states R2 and R6 could be replaced with ul.ieii or more capacitors to produce a momentary output. The number the illustrated entry and exit points are for explanatory purposes only. Type and number of those used in practice Inputs and outputs depend on the particular application. Some types of application are further described below.

Fig. 2 shows the circuit diagram of the NPN version of the logic element, the parts of which have the same function as the like-numbered parts in Fig. 1. This link creates a reverse link to that of FIG. 1.

Outputs appear at terminals dl, d2, el, e2, f and g in FIGS. 1 and 2. Points f and g form the main operating points and one of these two must, as shown in FIG is to be connected to the corresponding supply line. In this and in the following figures, the linking

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members each shown in outline with only the corresponding connections. In order to generate a logic level output, only point f is connected to the supply line, which thus makes resistor Rl the collector load resistor (FIG. 5a). If you want to use an additional device
In addition to the logical outputs (eg an indicator lamp, a relay, etc.), the additional device is connected between the supply line and point g (FIG. 5b). A fail-safe circuit is obtained by connecting point f to the supply line, so that logical outputs can be formed even if the additional device or its circuit should become a circuit with an open operating sequence
(Fig. 5c). In some applications, the additional device can also be built into the link. Fig. 5d shows one way

to create a failover facility for the logical output only. This provides for the switching on of a resistor with a suitable value between the supply line and point g. A diode can be installed in series or parallel connection in the additional device and, if necessary, supplemented by a suitable resistor.
to obtain transition or feedback protection.

The mode of operation of the link according to FIG. 1 can be seen in connection with FIG. 3, which uses the PNP unit as a parking light failure detector for monitoring two lamps L ₁
and L ₂ illustrates. With the lamps L ^, L ₂ are two reflector

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appropriate value would be connected in series, so that an electrical voltage occurs across the resistors when current flows through the lamps. This voltage is sufficient for the base-emitter potential of the transistor associated with the lamp Reduce TrI or Tr2 so that little or no current flows through the transistor. In the link are series resistors consisting of resistors R4 and R8 built in, but at least in part due to the resistance of the cable feeding the lamp or an external resistance can be replaced. A combination of some or all of the above options is also possible. Because the base of both transistors through the bias circuit R5, D4 constant is held, no current goes through the transistors when current flows through both lamps, and the starting points dl, d2, el, e2, g are at their negative maximum level.

If one of the lamps L ₁ or Lp should fail, the assigned transistor becomes conductive, since its emitter is no longer supplied with a hindering voltage. This causes current to pass through the failure indicator lamp L1 while the other outputs rise to their maximum positive level. The unit remains in this state until the error has been eliminated. Any number of transistors can be connected in this way. The number of transistors depends on the number of lamps to be monitored. The resistors produce outputs to resistively connected circuits,

2 UUH 2 i / 0 6 7 2

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while the diodes create switched levels for logic puncture circuits and similar applications. The circuit diagram in Pig. ¹ shows the I (in reference to FIG. 2 described above) and NPN Versio [i this circuit compared to that of Figure 3 the reverse link.. Accordingly, Figure 3 provides a negative AND / NAND function, while Figure 4 presents a positive AND / NAND function.

Figures 6a and 6b show those used for logical OR functions Links. A positive signal from the PNP element (Fig. 6a) at each input forms a conduction path for the associated transistor, which causes the output level from its most negative to change to its most positive value according to the OR function with positive link. Arouse accordingly negative signals the NPN element (Fig. 6b) for forming the OR function with negative link. Such circuits can find general use for systems in which the same Error can occur more than once (e.g. when the vehicle doors are not closed).

This OR function can be used to generate a further useful function with an inverted AND signal, as shown in FIGS. 7a and 7b get connected. The PNP element conducts when the input In 3 is negative and either the input In 1 or the input In 2 are positive. The NPN element generates this function in reverse connection. A typical application would be to generate an output signal if the

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- li -

The ignition is on and one or more of the seat belts are not buckled.

An AND puncture with three inputs can be achieved when the element according to FIG. 8 is connected when the power supply is used as an additional input so that all three inputs require energization before an output occurs.

A positive / negative AND gate with double input is obtained when connecting the link according to FIGS. 9a and 9b. These figures show some of the link possibilities available with this link.

Relays can be used in circuits according to FIGS. 10a and 10b. The windings can run in opposite directions on one and the same relay or be arranged on two separate relays. The output circuits would be connected by appropriate contact connections be formed on the relay. The positive and negative link can be achieved by suitable arrangement of the bias circuit and the input diodes.

Two other forms of this circuit are shown in FIG. 11b, in which emitter control is used instead of base control of the transistor. Bias is applied as in the previous case, but if sensitive operation is required, it can only be the + base emitter passageway,
+ des

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Another way of colletor switching to prevent Current returns can be achieved by using separate collector loads and isolating diodes and / or resistors accordingly Fig. 11b can be implemented.

For power signal circuits, the link for control can of either PNP or NPN transistors by connecting appropriately Find use, as shown in Fig. 12a and 12b as well as 13a and 13b. PNP power transistors are used controlled by the PNP gate (Fig. 1) simply by having the base of the power transistor (Fig. 12a) connects to point g and point f to the negative supply line. The NPN linkage requirement requires connection the base of the power transistor at de point f. For the NPN power transistor operated by the PNP logic element it is only necessary to connect its base to point f while at the NPN link this type of transistor is controlled when the point f is connected to the positive supply line and the power transistor base connected to point g ..

The link can thus, as can be seen, a large number of widely used in motor vehicles • Carry out linkage functions and power operation controls.

Bas level converter (Fig. 1 * 1 to 20)

This link consists of three transistors, which are designed as three-stage

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~ 2 ^ 55841

Switches with a suitable bias level are connected to the input. By using complementary transistors wi ^ d the current drain in the operational state reduced to a minimum.

In FIG. 14, the base circuit of the input transistor TrI is provided with a resistor R1 which can provide current limiting, a base bias current or a ground circuit. The emitter circuit has a resistor R * i across which a bias voltage can be developed. The collector circuit consists of a load resistor R3 connected to the BaoC of the second transistor Tr2 and a base-emitter temperature stabilizing resistor R2. The collector circuit of the transistor Tr2 consists of the collector resistor R6, which is connected to the base of a third transistor Tr 3, and a base-emitter temperature stabilizing resistor R7. The diodes Dl ₁ D2 form two logic outputs that change over when the circuit is energized from the negative level to the positive level. The collector circuit of the third transistor produces a number of functions; the resistor R5 generates bias current and signal return for the Trl emitter] if necessary, the resistor R8 creates a collector load; furthermore, a direct connection to the collector is created and the two diodes D3 and DM result in logical output signals, which is the opposite of that of the diodes Dl andD2 g -

20112 T IQfTX - :. {. · Ν

2156841

created signals are. For · practice these limbs must not all of the parts shown, but only the parts actually required for their function.

The way it works is as follows: If the input level is less positive than the emitter of the transistor TrI, then the Emitter junction of this transistor non-conductive, ao that Vein Current flows in the collector circuit of the translator TrI. This means that the transistor Tr2 does not conduct since no base current flows. Therefore no collector current flows during the Transistor Tr2. This in turn means that base current flows in the transistor Tr ", so that there is also no collector current in it Transistor flows. As soon as the input voltage is positive enough that the emitter junction of the input transistor TrI is conductive collector current flows in this transistor. This generates a current flow in the transistor Tr2, so that its collector potential changes over from the negative supply level to the positive supply level. In addition to generating a Flow of base current in the transistor TrjJ the signal output diodes Dl and D2 are forward biased to a to create positive signals. Since a base current flows in the transistor Tr3, a base current also flows in its collector circuit and generates a tilting of the collector potential of • the positive supply line to the negative supply line, which energizes the collector load circuit j Has..

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Transistors in the opposite way working circuit possibility.

Figures 16a-d show a collector circuit of the transistor Tr3 for a number of possible punctures. When point d is connected to the positive supply line, an output signal results at point c (Fig. 16a). If it is necessary to control an external consumer, he can choose between point c and the positive supply line (Fig. 16b) can be switched. A fail-safe circuit can be an external consumer be assigned in such a way that the point d is connected to the positive supply line and the consumer between the supply line and point c (Fig. 16c) is switched on, so that the consumer circuit should have an open Effect sequence preserved, the signal outputs of the limbs would still work. Correspondingly, if only one Signal output is required, the failover can be created by adding an external load resistor as shown in Fig. l6d is connected between the positive supply line and point c.

Power transistor control is achieved by appropriately connecting points c and d as shown in FIGS. 17a and 17b for

PNP Tüansistors and corresponding to Fig. 18a and b for NPN- ' Transistors. It is a simple step to develop this unit into an automatic light-controlled switch, if one this power circuit with a light-responsive resistor

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stand LDR and a variable resistor VR (for plague of the operating level), which are connected to points b and a, respectively, according to FIGS. 19a and 19b. In Figures 20a and b, the level conversion unit is connected in such a way that, in conjunction with a display device M, it displays a visible level display he brings. In Fig. 20a a high level operation is shown, while Fig. 20b shows a circuit for a Shows low level operation.

The Zeilgeber (Fig. 21-30)

This third unit is shown in FIG. 21 and is used to generate a wide range of time periods with variable Duty cycle (mark to space ratio) formed. The timer consists of a single-face transistor Tr3 (or of the Creation of an equivalent to this switched transistors). A negative pulse is at base 2 (point m) and a positive impulse that of base 1 (point n) is present. Resistor R8 provides temperature compensation as well a load resistor for the negative pulse. Resistor R9 is the load resistance for the positive pulse.

Direct access to the emitter or timer connection is available at point d. Are also connected to this point three time control resistors R5 _f R6, R7, which generate a plurality of time functions. R5 is the minimum value that enables the circuit to function as an unstable oscillator,

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so that it can be used as a limiting resistor for variable timing applications and as a maximum frequency connection for switched or fixed frequency applications can be used. Resistors R6 and R7 generate alternating frequencies for multiple frequency applications. If the timer is used, for example, as a tone generator is used, R6 and R7 produce octave drops in which frequencies i.e. R6 s 2 χ R5 and R7 = 2 χ R6. A capacitor Cl is permanently connected to the circuit, while a capacitor C2 is arranged in such a way that it is connected in parallel with Cl or

can be connected in a number of other ways. Resistor RIO creates a high resistance path for the emitter circuit when the emitter is not conducting. The diode Dl creates a low impedance path for any negative pulses.

The transistor Tr2 forms a device with a variable duty cycle for the unstable oscillator Tr3, the spacing time being dependent on the values of the parts RiJ and Cl and the total time is determined by Cl and R5 (or R6 etc). Resistor R3 forms the collector load of transistor Tr2 and the resistor R2 produces a temperature stabilization for the output transistor TrI. This transistor has a direct Output from the collector (point j) or an output via a current limiting resistor Rl + suitable value.

Fig. 22 shows the circuit of a complementary timing element which

a corresponding function with a negative supply ♦ with

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line generated. Both elements can control power transistors. NPN power transistors were connected as shown in FIGS. 23a and 23b and PNP power transistors as shown in FIGS . 2ka and 24b. This additional part enables the direct control or regulation of power circuits, e.g. for motors or lamps.

A main application of the timer in security systems is its use as an oscillator or flasher switch. In FIGS. 25a and 25b, the timers are connected as tone generators. A loudspeaker LS of suitable impedance is connected between points j and 1 and a variable resistor is connected to the Point a connected in series so that the frequency of the oscillator can be changed. When the contact closes, the changes Frequency of the oscillator at a second level above. If there is no contact to point a, the circle will only oscillate, when the contact is closed so that an audible indication of the switch closure can be generated.

26a and 26b show the circuit of the timer as a flasher switch or transmitter for a lamp L. The variable resistor connected in series with point a changes the interval between Flashing processes and the closing of the contact changes the Ries interval by a specified value. There is no circuit on connected to point a, the lamp L only flashes when the contact is closed. .

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For some applications, working for a short time is the acoustic warning signaling., all that is required. this can be achieved by using the timer according to FIGS. 27a and 27b switches ". When the switch S is closed, the capacitor. C2 is not charged and can only pass through the resistor R5 so that a few seconds pass before the capacitor is charged enough to prevent the circuit from tripping. The effective input voltage drops during the charging period. Hence the frequency also increases proportionally so as to produce a sloping tone, which has been found to be very effective in drawing attention to something.

The speed of a DC motor is related to the effective voltage applied to it. By using the timer with a Lexstungstransistor it is possible to change the required voltage by changing the interval bring about current pulses supplied between the motor. A circuit for this is shown in FIGS. 28a and 28b. The speed range of the motor M is determined by the fixed resistor R and external variable resistors VR, which with connected to point e.

An intermittent operating mode can also be varied, as shown in Figures 29a and 29b. The windshield wiper motor M only works when either the power transistor TrI is energized or the switching contact A after a period of time is closed by setting the second

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Variable resistor VR2 is determined. When the power transistor TrI is de-energized, the motor continues the drive until the end of the wiper blade path because the switching contact is closed. This circuit can be matched with the motor be coupled to the windshield washer-controlling circuit, so that both the washing and the wiping frequency, as well as the number of work processes can be completely controlled. For a simpler system, the on-time control is used is set to a fixed value as shown in Fig. 30 for the washer timer.

Attachments (Fig. 31-43)

A complete system using the above-described members can consist of five blocks. These are alarm, failure, Warning, level and performance blocks. Each block consists of a suitable one to generate the required functions Combination of units. A scheme for such a system is shown in FIG.

In its simplest form, the alarm block consists of a level element that has an indicator lamp for visual alarm signaling (Fig. 16) operated. A simple acoustic alarm can be given. can be generated by a timer that omits the Connection to point a connected to a loudspeaker according to FIG is. Is the acoustic alarm for only a few

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Seconds are necessary, the timer is accordingly Pig. 27 switched.

A further alarm block can be activated by combining a timer connected as shown in FIG Pig. 16 switched level reshaping member are created. This creates a decreasing signal that lasts a few seconds Frequency in connection with a permanent lamp signal. Thus, the sound first draws the driver's attention for the fact that an error has occurred while the lamp is continually reminding him that the error has occurred still exists. By using separate excitation leads to the time and level member as shown in FIG the reliability is increased.

This can increase the reliability of the alarm block that two time units as shown in FIG. 33 are combined with one another. The first timing element generates output pulses low frequency to the second timer uM the warning lamp Ll to excite, so that the lamp flashes in larger intervals and at the same time audible when an error occurs Sound bursts are generated by loudspeakers * The connection of excitation points and the use of two separate ι Input lines gives the most reliable alarm block according to Fig. 34. By connecting point h of the Niveja member at point f of the second timing element, both ejine initial warning, as well as an additional warning signal can be issued by the lamp L 1. 'ι

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Any in facilities attached to the dropout block, the level block or the warnbloek are connected, occurring error causes the input of the alarm block to be excited, the in turn generates an optical and / or acoustic alarm in one of the ways described above. The special kind of Circuit of the alarm block depends on the total cost and the necessary reliability.

The failure block consists of a number of failure links, the like from Pig. 35 can be seen from the various lighting circles and the alarm block are connected. The failure members are in terms of their inputs according to FIG. 3 or 4 and switched with regard to their outputs according to FIG. In addition, excitation outputs are connected to the alarm block, to produce an initial display. Individual lamps each Limbs are used to indicate which particular circle has failed, so the failure on the central block and is also displayed on the special circuit display · Otherwise, the points d of the failure elements are connected in parallel to bring about a single warning signal.

The level block consists of a number of levels, which are connected to transforming circuits for level, pressure, temperature, etc. are. If the current exceeds or falls below a predetermined level, an output is generated, which assigns both the alarm block and the level element

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arranged + indicator light energized. For circles to plague too high currents are the level members according to FIG. 20a and for circles to detect currents that are too low the level members switched according to FIG. 20b. The output circuits can be seen in FIG. 16 with FIG. 36 Excitation lines connected to the alarm block. Otherwise, a single indicator light can be created by connecting all of the Starting points of the level members are operated on a common rail.

The warning block can use a combination of elements to identify and display particularly undesirable conditions. Failure members are used to determine coincident conditions, while level members are also provided when particular levels are important. Fig. 37 shows a typical one Block for generating normal warning conditions for automobiles «

The performance block consists of a combination of performance elements with corresponding time, level or failure elements.

With a light-dependent resistor, a level element and a power element, an automatic control of the limiting lamp circuit be generated. According to FIG. 38, additional power elements control the headlights and low beam.

As can be seen from Fig. 39, a temperature-dependent - »special ^!

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Resistance, a timing element and a power element are different Drive speed for a heating / cooling fan for temperature control. An alternative design the timing circuit for this and other uses is shown in FIG. Windshield wiper and washer control circuits are already described above for FIG.

A power element and a timer form a circuit that can operate a blinking direction indicator. In 41 forms an additional second power element Two-stage flashing circuit (for flashing lights A and B) as prescribed in certain countries.

42, a timer can be used as a digital / analog converter used to make linear circles for tachometer and speedometer. This link can also for determining the speed of automatic gearbox systems, with the logical Control through the failure elements and delays through timing elements are created.

ORIGINAL INSPECTED 209821/0672

Claims (9)

- 25 claims; 1. Electrical system for vehicles, characterized by Links for determining changes in the or Failure to operate the facility or to control the supply of power to parts thereof. 2. Installation according to claim 1, characterized in that at least one of the logic elements is a Pestkörper circuit having. 3. Plant, marked by a) one or more output converters for playback or display of the status of the system, and - b ) one or more link elements for connecting the or each output converter with components of the electrical equipment of drive motors, gears or brakes of a vehicle. 4. Plant according to claim 3, characterized in that the Logic links comprise solid state circuits. 5. Plant according to claim 3 »characterized in that at least one link from the a) an orund switch that generates an AND or a QR link as an output depending on the given inputs, 1/0672 ORiGINAL INSPECTED b) a level converter b; sw, -fixing element, da; i at a A switching process is generated at the predetermined voltage level , and c) a pulse generator switching element for generating output pulses existing over a range of time intervals Group is selected. 6. Electrical system for vehicles, characterized in that that it comprises one or more of the following electronic blocks: iy an alarm block with at least one basic switching element which, depending on a given input , generates an ANDt or an OR link as an output, 2) a level block having at least one Niveausehaltglied that generates a switching operation at a predetermined voltage level, said block responsive to vehicle operating conditions Eingangsumformerkreise be connected, 3) a warning block with at least one basic switching element, pulse generator switching element or level holding element which, as an output, generates an AND or an OR link or such a combination of links that a warning signal output occurs in response to a given input to the element, and 209821/0672 owQWAL inspected ¹ O a power block with one or more power supply elements for supplying parts of the electrical equipment of the vehicle, with the output of the or each power supply element either through a basic switching element that generates an AND or an OR link as an output, or by a pulse generator switching element that generates a range of time intervals with a variable duty cycle, or by a level switching element that is changed with the load. 7. Installation according to claim 5, characterized in that the basic switching element has two transistors with coupled base terminals having a common bias circuit. 8. Plant according to claim 5 »characterized in that the level switching element consists of a transistorized switch, which has at least two stages and a bias circuit for regulating the input voltage to the first stage. 9. Plant according to claim 5, characterized in that the pulse generator circuit element comprises a circuit with a Einflächentransistor and resistance means which enables the operation of the circuit as an unstable oscillator. 209821/0872