Electronic equipment

Abstract

The invention relates to an electronic device (1) for controlling a load in an electric circuit, the electronic device (1) comprising a single-layer or multi-layer circuit board arrangement (12) with electrical components and conductive tracks and comprising a load circuit (2) and a control circuit (3). According to the invention, in order to provide an electronic device with a device-specific protection device for short circuits and overloads, the load circuit (2) and the control circuit (3) are at least functionally interconnected, and the electronic device (1) comprises a first overcurrent protection device (4) for protecting against short-circuit currents and a second overcurrent protection device (5) for protecting against overload currents.

Description

Technical Field

[0001] The invention relates to an electronic device arrangement according to the preamble of claim 1. Background Art

[0002] Such electronic devices can include switching contacts, for example, switching contacts of power semiconductor devices or relays for load current conduction and electronic control devices for controlling power semiconductor devices or for controlling relay coils.

[0003] Such electronic installation devices are often used in electrical installation systems in building service technology and are designed for load currents significantly lower than the rated current of typical building installation circuits, for example 16 amps. For example, blind switches, timers, etc. are designed for load currents in the range of 3 amps to 8 amps.

[0004] When testing according to the standard, the electronic installation device must be tested with the trip current of the fuse element (preferably a circuit breaker) connected upstream of the building service. Due to the difference between the load current of the electronic installation device and the trip current of the upstream connected building-side fuse element, the electronic installation device may be under-fused, i.e. too high. If an overcurrent occurs between the rated device current and the trip current of the upstream connected building service fuse element, the electronic installation device will not be protected and may be damaged.

[0005] In terms of safety technology, in this case, it is necessary to provide a device-specific fuse to protect against overcurrent. It is known to use a fast-response lead fuse as a device-specific fuse in an electronic system having a load circuit and a control circuit, and the fast-response lead fuse is preferably arranged in the load circuit. The electronic system is reliably protected from the influence of short-circuit current in the load circuit by such an overcurrent protection device.

[0006] If the current flowing in the load circuit is less than the short-circuit current, but greater than the rated device current, electrical components may still be damaged. Usually, this so-called overload is defined as exceeding the permissible current in an electrically undamaged circuit. In this context, the heat development caused by the current can destroy electrical conductors and components by exceeding the permissible limit temperature. Overload protection devices detect the heating of conductors and / or components and at least temporarily shut down the circuit.

[0007] Short-circuit currents and overload currents result in different technical requirements for protective devices. In the event of a short circuit and an overload, the current-carrying lines heat up to unacceptably high temperatures. The essential difference is that in the event of a short circuit with a high short-circuit current, unacceptably high heat can be reached within a fraction of an electrical half-oscillation. In the event of a high short-circuit current, the lead fuses also melt in a sufficiently short time. In the event of an overload, currents that are only slightly above the maximum permanently acceptable load capacity of the line occur and only heat the line to unacceptably high temperatures after a longer time. In circuits loaded in this way, fuses, preferably reversible fuses, can ensure that unacceptably high temperatures are not reached at the conductors and components and that protection is present in the event of an overload.

[0008] With a lead fuse inside a single unit, both short circuit conditions and overload conditions can be fused. In this regard, however, the lead fuse rating is based on a lower value for overload conditions. This can cause the fuse to trip more often than necessary. The downside is that such lead fuses are destroyed after tripping and must therefore be replaced in order to restore functionality to the unit after the overload condition is eliminated.

[0009] Known device circuit breakers or miniature circuit breakers, which are all dedicated to fuse protection in overcurrent situations, cannot be used with electronic devices that are implemented in small components and mainly on conductor tracks due to their size and structure. Thermal protection devices with mechanical components cannot be used as overload protection due to their size.

[0010] Furthermore, self-resetting fuses are known, for example, electrical components with PTC (positive temperature coefficient) characteristics, which include a polymer-based positive temperature coefficient thermistor with a nonlinear resistance curve. Such a positive temperature coefficient thermistor is low impedance at normal temperature. If the positive temperature coefficient thermistor heats up, for example due to external heat supply, it becomes high impedance, thereby greatly limiting the current. If the heat supply is reduced, the positive temperature coefficient thermistor cools down and becomes low impedance again.

[0011] Electronic installations are mainly implemented as small components on conductor track packages. To date, the implementation of a complete overcurrent protection based on a conductor track structure is still unknown, because in particular the usual conductor track geometry with small layer thicknesses and large surfaces is not suitable for loads with different current limit values. Short-circuit protection with lead fuses requires a higher fuse integral at all other points of the conductor track structure and therefore a larger conductor track surface. In contrast, the heating and heat dissipation of the conductor required for overload protection by PTC elements cannot be achieved with the usual conductor track widths. However, in the event of a short circuit, the required tapered conductor track will be destroyed.

[0012] Implementing PTC-based overload protection will make individual short-circuit protection on the conductor track package impossible. The corresponding fuses of the premises installation, usually reversible automatic circuit breakers, will have to be replaced according to the lower rated current of the facility installation.

[0013] A solution that specifically and optimally protects electronic installations from both overcurrent conditions is not yet known. Summary of the invention

[0014] The object of the present invention is therefore to eliminate the above-mentioned disadvantages and to create an electrical installation device which has a device-specific protection against short circuits and overloads.

[0015] This object is met by the features stated in claim 1. Advantageous embodiments emerge from the dependent claims.

[0016] The invention according to claim 1 has the advantage that the electronic installation device according to the invention is protected against overcurrents by a combination of two mutually coordinated special protection devices: a first overcurrent protection device protects against short circuits, while a second overcurrent protection device fuses against overloads.

[0017] The electronic device can preferably be connected in series with the load. From a technical circuit point of view, the electronic device can include a load circuit and a control circuit that are thermally and physically / electrically coupled. The load circuit can have a first overcurrent protection device, a resistor element, and a circuit interruption element that can be arranged in series between the current source and the electrical load.

[0018] The overcurrent detection device may cooperate with the control device as a second overcurrent protection device. The control device may be arranged in the control circuit and may be functionally connected to a circuit interruption element in the load circuit. The overcurrent detection device may include: a sensor element in the control circuit, preferably a reversible electronic element, such as a sensor element in the form of a positive temperature coefficient (PTC) thermistor; and a resistor element in the load circuit thermally coupled to the PTC. The resistor element extends as a conductor track galvanically separated below the PTC element.

[0019] The electronic device can be implemented at least partially on a circuit board arrangement and can have a first overcurrent protection device in the form of a lead fuse in the load circuit, which protects device-specific electrical components and conductors in the event of a short circuit. This means that the melting integral of the protected components and conductor tracks is higher than the melting integral of the fuse. Fuses are designed only for short-circuit situations and not for overload situations.

[0020] The resistor element in the form of a conductor track of the load circuit is particularly suitable, on the one hand, for not being destroyed in the event of a short circuit and, on the other hand, for being able to detect thermal energy in the event of an overload. In this case, the conductor track can comprise two conductor tracks of different widths connected in parallel. In this respect, the width ratio is preferably 5 to 1. The wide conductor track absorbs the short-circuit current, while the narrow conductor track serves to detect the overload state. In this respect, the common melting integral of the two conductor tracks is higher than the melting integral of the lead fuse.

[0021] Under normal operating conditions, the electronic installation device is in a state with low temperature and low resistance. In the event of a short circuit, the current increases very quickly and causes the fuse element in the first overcurrent protection device to melt, whereby the current flowing through the fuse is permanently interrupted. Since the common melting integral of the two conductor tracks of the resistor element is high, no damage occurs at this point. The narrow conductor tracks are not damaged in this respect, because the current uses the path of least resistance via the wide conductor tracks of sufficient size when flowing at high currents in the event of a short circuit. The lead fuse does not trip in the event of an overload in the range between the short-circuit current (tripping current of the lead fuse) and the rated current of the installation device.

[0022] In the event of an overload, the current through the resistor element increases relatively slowly, where the ambient temperature of a narrow conductor track in particular increases excessively and remains longer than in normal operation. The sensor element is "triggered" by the ambient temperature of the conductor track, i.e. changes into a state with high temperature and high resistance, so that the current is significantly reduced. The change in resistance and current value is "communicated" to the control device and causes therein a circuit interruption element (e.g. a relay or power semiconductor device) in the load circuit to change from a normal operating state to a triggered state, so that the load is also disconnected.

[0023] In the control circuit, the sensor element can form a voltage divider with a resistor, the changing voltage of which is read into the microcontroller and processed. When an overload is identified, the relay or power semiconductor device connected to the microcontroller is disconnected, and the load in the load circuit is therefore also disconnected. Alternatively, if an overload occurs, it can also be disconnected without a microcontroller. If the overload current in the load circuit increases further, the narrow conductor track of the resistor element heats up further until the reduced control current of the sensor element is lower than the holding current of the relay. The relay drops out and opens the load circuit. The sensor element remains in the triggered state until the temperature returns to normal and is able to cool down. Then it returns to the normal state, i.e. repeated connection of the load. The sensor element is not arranged in series with the load and can therefore be operated at a much lower current level than the normal circuit flowing through the load.

[0024] The width of the two conductor tracks of the resistor element is determined according to the following rule. For short-circuit considerations, the energy absorbed in the form of a melting integral is relevant. The melting integral of the conductor track of the facility equipment must be higher than the melting integral of the fuse. The common melting integral of the two conductor tracks of the resistor element must also be designed according to this specification. The ratio of the melting integrals of the conductor tracks to each other is preferably a ratio greater than 25.

[0025] Due to these specifications, the diameter of the round conductor can be determined by converting the melting integral of the lead fuse associated with the round conductor. The resulting cross section can be converted into the minimum width of the two conductor tracks. When the ratio of the melting integrals of the two conductor tracks is assumed to be 25 to 1, the ratio of the widths of the conductor tracks is 5 to 1. In this regard, it is assumed that the two conductor tracks are made of the same material and have the same thickness.

[0026] The electronic facility device according to the present invention may at least partially include a layered or packaged arrangement of a circuit board, which includes one or more substrate layers, and electrical components and / or conductor tracks are arranged on each substrate layer on one side or both sides. Two overcurrent protection devices are advantageously formed at the two outer main surfaces of the circuit board arrangement. A first overcurrent protection device in the form of a lead fuse can be arranged on the lower substrate layer, and a sensor element in the form of a PTC element of at least a second overcurrent protection device can be arranged on the upper substrate. The conductor tracks of the resistor elements connected in parallel are arranged below the sensor elements. The correspondingly structured resistor elements can advantageously include wide conductor tracks and tapered conductor tracks and can be arranged in different substrate layers of the circuit board structure. The narrow conductor tracks can be arranged in particular near or on the surface of the outer layer to enable the use of sensor elements (SMD technology) on the surface of the circuit board arrangement. The tapered conductor tracks can have a reduced width or thinned height dimension. In addition to the circuit-related functions, the individual layers of the circuit board structure are also used to maximize the area of ​​the conductor tracks to withstand short-circuit currents. FR4 with a common height is used as a standard dielectric. Suitable sensor elements include PTC conductive polymers, ie compositions comprising organic polymers and particulate conductive fillers and / or conductive inorganic fillers.

[0027] The electronic installation device according to the invention is generally used to protect circuit arrangements with device-specific relatively high current loads and relatively low voltage loads, such as blind switches, timers or fans. Such circuits generally include electrical loads that cause overcurrents when the load (e.g. a motor) trips or under more difficult operating conditions. One advantage of an electronic installation switch with an integrated overcurrent protection device is that it can be safely used in already existing circuits, which are themselves overprotected by fuses. With the arrangement according to the invention, a specific (higher) installation-internal short-circuit fuse can be used, which neither requires replacing the usual automatic circuit breaker of the house installation nor has a (lower) value for overload current (e.g. 10 amperes instead of 8 amperes) to minimize temperature effects. Since the fuse is only used for short circuits and not for overloads, the electronic installation device can be protected from impermissibly strong heating. Therefore, a typical fuse size (16 amperes) can be used on the house installation side. In the installation device, the short-circuit situation is protected solely by a first overcurrent protection device in the form of a lead fuse. The overload situation is protected by a second overcurrent protection device instead of a lead fuse. A robust circuit is produced which can also be used for motor loads of increased specification (eg under abnormal conditions the device can handle 8A current without particular anomalies).

[0028] The basic structure of the circuit board arrangement can remain unchanged. The materials and material thicknesses of the substrate, the insulating layer and the conductor tracks remain unchanged. The conductor track cross-section can be further realized by an optimized width-to-thickness ratio, so that a compact and cost-effective production with a small product size in a small space can be achieved. The use and arrangement of electronic components can also be maintained. The principle of the invention can be used for larger circuit board arrangements and subassemblies with printed circuit tracks and components. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further details, features and advantages of the invention emerge from the following description of preferred exemplary embodiments with reference to the drawings.

[0030] The following is shown:

[0031] Figure 1 Is the circuit arrangement of an electronic facility device;

[0032] Figure 2 is a schematic circuit board layout in plan view;

[0033] Figure 3 is a schematic circuit board arrangement in cross-sectional view; and

[0034] Figure 4a -d is based on Figure 2 and Figure 3 The different layers of the circuit board layout. DETAILED DESCRIPTION

[0035] In the following description, components that are the same or have the same effect are provided with the same reference numerals.

[0036] Figure 1 The basic circuit arrangement of an electronic installation device 1 is shown. The electronic installation device 1 can preferably be connected in series with a load (not shown). From a technical circuit point of view, the electronic installation device 1 comprises a load circuit 2 and a control circuit 3 which are thermally, physically and / or electrically coupled. The electronic installation device 1 is protected against overcurrent by a combination of two specific protection devices that cooperate with each other. The first overcurrent protection device 4 protects against short circuits, while the second overcurrent protection device 5 fuses against overload conditions.

[0037] The electronic device 1 comprises a circuit interruption element 6 in the form of a switching contact of a relay 7, by which the electrical connection of the load to the voltage source can be made and broken. The relay 7 is controlled by a control device 8 in the control circuit 3, which supplies switching commands to the coil of the relay 7.

[0038] The load circuit 2 has a first overcurrent protection device 4, a resistor element 9 and a circuit interruption element 6 arranged in series between a power source (not shown) and an electrical load. An overcurrent detection device 10 cooperates with a control device 8 as a second overcurrent protection device 5. The control device 8 is arranged in the control circuit 3 and is functionally connected to the circuit interruption element 6 in the load circuit 2. The overcurrent detection device 10 comprises a sensor element 11 of a reversible electronic element preferably in the form of a positive temperature coefficient (PTC) thermistor in the control circuit 3, and a resistor element 9 in the load circuit 2 which is thermally coupled to the PTC element 11. The resistor element 9 extends as a conductor track electrically separated below the PTC element 11.

[0039] The electronic device 1 is implemented at least partially on a circuit board structure 12 and has a first overcurrent protection device 4 in the form of a lead fuse in the load circuit 2, which protects device-specific electrical components and conductors in the event of a short circuit. This means that the melting integral of the protected components and conductor tracks is higher than the melting integral of the fuse 4. The fuse 4 is only designed for short circuits and not for overloads. The certified fuse 4 used is suitable for minimizing temperature effects and handling tripping currents. In the event of a short circuit, the load circuit 2 is permanently interrupted by the fuse 4.

[0040] The resistor element 9 in the form of a conductor track of the load circuit is particularly suitable on the one hand for not being destroyed in the event of a short circuit and on the other hand for being able to detect thermal energy in the event of an overload. In this case, the conductor track comprises two conductor tracks 13 and 14 of different widths connected in parallel. In this respect, the width ratio is preferably 5 to 1. The wide conductor track 14 absorbs the short-circuit current, while the narrow conductor track 13 is used to detect the overload current. In this respect, the common melting integral of the conductor tracks 13 and 14 is higher than the melting integral of the lead fuse 4.

[0041] refer to Figure 1 , the operation of the electronic facility device 1 according to the present invention will be described below. In this regard, the electrical network of the residential equipment can provide the electronic facility device 1 with an operating current. When the circuit interruption element 6 of the relay 7 is closed in the load control circuit 2, the operating current flows to the load, such as a brushed motor with a higher current for blind control. A control current source separate from the primary current source provides a control current to the control circuit 3. The control current flows to the coil of the relay 7 via the sensor element 11, and normally closes the circuit interruption element 6, thereby closing the load circuit 2. Under normal operating conditions, the electronic facility device 1 is in a state with low temperature and low resistance.

[0042] The fault current is the current level that damages one of the components of the circuit. In the event of a short circuit, the current increases very quickly and causes the fuse element in the first overcurrent protection device 4 to melt, whereby the current flow is permanently interrupted. Since the common fuse integral of the two conductor tracks 13 and 14 of the resistor element 9 is high, no damage occurs at this point. The narrow conductor track 13 is not destroyed in this respect, because the current uses the path of least resistance via the wide conductor track 14 of sufficient size when flowing at high currents in the event of a short circuit. The lead fuse 4 does not trip in the event of an overload in the range between the short-circuit current (tripping current of the lead fuse) and the rated current of the electronic installation device 1.

[0043] In the event of an overload exceeding the rated device current, such as a motor stall, the current through the resistor element 9 increases rapidly but relatively slightly, where the ambient temperature of the narrow conductor track 13 in particular increases excessively and remains longer than in normal operation. The PTC element 11 is "triggered" by the ambient temperature of the narrow conductor track 13, i.e. switched to a state with high temperature and high resistance, whereby the current is significantly reduced. The changes in resistance and current values ​​are "transmitted" to the control device 8. In the control circuit 3, the PTC element 11 forms a voltage divider with the resistor 15, the changing voltage of which is read into the microcontroller 16 and processed. When an overload is identified, the relay 7 connected to the output 17 of the microcontroller 16 via the transistor 18 is disconnected and the corresponding functionally connected circuit interruption element 6 is opened and thus also disconnection of the load occurs. Different operating modes can be set at the microcontroller 16. Thus, for example, it can be defined whether the load is automatically connected again after a certain period of time, or only after a repeated switch-on command, or after an interruption reset of the load circuit 2. The triggering characteristics are also selectable.

[0044] Alternatively, disconnection can also be carried out without the microcontroller 16 in the event of an overload. If the overload current in the load circuit 2 increases further, the conductor track 13 and the sensor element 11 will heat up further until the reduced current in the control circuit 3 is below the holding current of the relay 7. The relay coil drops out and opens the load circuit 2 via the circuit interruption element 6. The PTC element 11 remains in the triggered state until the temperature is normal again and can cool down. Then the normal state is returned, i.e. the load is reconnected. The PTC element 11 is not arranged in series with the load and can therefore be operated at a much lower current level than the normal current flowing through the load.

[0045] refer to Figure 24, a possible circuit board structure 12 of an electronic device 1 is shown, which includes one or more substrate layers 19 to 22, the one or more substrate layers 19 to 22 having a dielectric core layer with electrical components and / or conductor tracks each arranged on one or both sides. Two overcurrent protection devices 4 and 5 are at least partially formed at the two outer main surfaces 23 and 24 of the circuit board structure 12. A first overcurrent protection device in the form of a lead fuse 4 is arranged on the lower substrate layer 19, and a sensor element 11 in the form of a PTC element of at least the second overcurrent protection device 5 is arranged on the upper substrate layer 22. Conductor tracks 13 and 14 of a resistor element 9 electrically connected in parallel are arranged below the PTC element. The correspondingly structured conductor tracks are arranged in different substrate layers of the circuit board structure 12. The tapered conductor track 13 is arranged in the substrate layer 20, while the wide conductor track 14 is arranged in the substrate layer 21. The two conductor tracks 13 and 14 are directly connected via a conductive path. The narrow conductor tracks 13 are arranged particularly close to the surface in the layer 20 to enable the use of the PTC element 11 on the surface (SMD technology). The PTC element 11 on the substrate layer 19 is in thermal contact with the substrate layer 20 just above the surface of the tapered conductor tracks 13, so that heat generated there due to the overcurrent condition is effectively transferred to the PTC element 11 to generate a control signal as described above.

[0046] Ideally, the layers of the circuit board arrangement 12 are as thin as structurally practical. The dielectric material forming the substrate can be a thin polyester material or another suitable thin flexible substrate. A thin but relatively rigid glass fiber reinforced resin substrate can also be used. The structuring of the copper layer can be carried out by conventional photoresist and chemical etching techniques known to those skilled in the art. In addition to the functions related to the circuit, the various layers of the circuit board arrangement are also used to maximize the area of ​​the conductor tracks so that they can withstand short-circuit currents. For the insulation between the substrate layers of the circuit board arrangement, layers 25 to 27 of FR4 with a common height are used as standard dielectrics. Suitable PTC elements 11 include PTC conductive polymers, i.e., compositions comprising organic polymers and granular conductive fillers and / or conductive inorganic fillers.

[0047] The description of the above embodiments is for illustrative purposes only and is not intended to limit the present invention. Various changes and modifications may be made within the framework of the present invention without departing from the scope of the present invention or its equivalents.

[0048] Reference numerals list

[0049] 1 Electronic equipment

[0050] 2 Load circuit

[0051] 3 Control circuit

[0052] 4. First overcurrent protection device

[0053] 5 Second overcurrent protection device

[0054] 6 Circuit interruption elements

[0055] 7 Relay

[0056] 8 Control device

[0057] 9 Resistor Components

[0058] 10 Overcurrent detection device

[0059] 11 Sensor element

[0060] 12 Circuit Board Layout

[0061] 13 Narrow conductor tracks

[0062] 14 wide conductor tracks

[0063] 15 Resistors

[0064] 16 Microcontroller

[0065] 17 Output

[0066] 18 Transistors

[0067] 19 Basal layer

[0068] 20 Basal layer

[0069] 21 Basal layer

[0070] 22 Basal layer

[0071] 23 Surface of base layer 19

[0072] 24 Surface of the base layer 22

[0073] 25 Insulation layer

[0074] 26 Insulation layer

[0075] 27 Insulation layer

Claims

1. An electronic device (1) for controlling a load in an electric circuit, the electronic device (1) having a single-layer or multi-layer circuit board arrangement (12), the circuit board arrangement (12) having electrical components and conductor tracks, and comprising a load circuit (2) and a control circuit (3) which are at least functionally connected to one another, characterized in that The electronic equipment device (1) has a first overcurrent protection device (4) for protecting against short-circuit current and a second overcurrent protection device (5) for protecting against overload current, and the load circuit (2) includes the first overcurrent protection device (4) which can be arranged in series between a current source and an electrical load, a resistor element (9) and a circuit interruption element (6).

2. The electronic equipment device according to claim 1, characterized in that: The control circuit (3) has a second overcurrent protection device (5), which has an overcurrent detection device (10) and a control device (8), and the control device (8) is functionally connected to the circuit interruption element (6).

3. The electronic facility device according to claim 1 or 2, characterized in that: The circuit interruption element (6) is functionally connected to a relay (7) or a power semiconductor device.

4. The electronic facility device according to claim 1 or 2, characterized in that: The first overcurrent protection device (4) is irreversible.

5. The electronic equipment device according to claim 2, characterized in that: The overcurrent detection device (10) comprises a reversible sensor element (11) in a control circuit (3) and a resistor element (9) in a load circuit (2), wherein the sensor element (11) is thermally coupled to the resistor element (9).

6. The electronic equipment device according to claim 5, characterized in that: The sensor element (11) is a positive temperature coefficient thermistor.

7. The electronic equipment device according to claim 5, characterized in that: The resistor element (9) is arranged as an electrically separated conductor track below the sensor element (11).

8. The electronic facility device according to claim 5 or 6, characterized in that: The resistor element (9) comprises two conductor tracks (13, 14) having different widths and / or thicknesses connected in parallel, the two conductor tracks (13, 14) comprising a narrow conductor track (13) and a wide conductor track (14).

9. The electronic equipment device according to claim 8, characterized in that: The width ratio between the two conductor tracks (13, 14) is 5 to 1 and they have the same thickness and the same material.

10. The electronic equipment device according to claim 8, characterized in that: The narrow conductor track (13) comprises a portion with a narrowed width or a portion with a thinned height.

11. The electronic equipment device according to claim 8, characterized in that: The wide conductor track (14) absorbs short-circuit currents, while the narrow conductor track (13) is used to detect overload currents.

12. The electronic equipment device according to claim 8, characterized in that: The two conductor tracks (13, 14) of the resistor element (9) are arranged in different layers (19, 20, 21, 22) of a circuit board arrangement (12).

13. The electronic equipment device according to claim 8, characterized in that: The narrow conductor track (13) is arranged close to or on the surface (24) of the outer layer (22), wherein the sensor element (11) is arranged in thermal contact and electrically insulated relative to the conductor track (13).

14. The electronic facility device according to claim 1 or 2, characterized in that: The fusing integral of the protected component and the conductor track is higher than the fusing integral of the fuse of the first overcurrent protection device (4).

15. The electronic equipment device according to claim 8, characterized in that: The common fusing integral of the two conductor tracks (13, 14) of the resistor element (9) is higher than the fusing integral of the first overcurrent protection device (4), the ratio of the fusing integrals of the conductor tracks (13, 14) to each other being a ratio greater than 25.

16. The electronic facility device according to claim 5 or 6, characterized in that: At least one sensor element (11) of the first overcurrent protection device (4) on the one hand and of the second overcurrent protection device (5) on the other hand are arranged on two outer main surfaces (23, 24) of a circuit board arrangement (12).

17. The electronic equipment device according to claim 1 or 2, characterized in that: The circuit board arrangement (12) comprises one or more layers (19-22, 25-27), electrical components and / or conductor tracks being arranged on one or both sides on each layer.

18. The electronic equipment device according to claim 17, characterized in that: The layers (19-22, 25-27) are at least partially flexible and / or inflexible.

19. The electronic equipment device according to claim 8, characterized in that: The overcurrent generates heat in the narrow conductor track (13) of the resistor element (9), which, due to the thermal coupling with the sensor element (11), causes a reaction in the control device (8) and thus causes a temporary interruption of the load circuit (2).

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