Circuit breaker device and method
Patent Information
- Application Number
- EP2024702253
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-02-27
- Filing Date
- 2024-01-18
- Publication Date
- 2025-11-05
Smart Images
Figure EP2024051110_06092024_PF_FP
Abstract
Description
[0001]202219605 1 Description Protective switching device and method The invention relates to the technical field of a protective switching device for a low-voltage circuit with an electronic interruption unit and to a method for a protective switching device for a low-voltage circuit with an electronic interruption unit. Low voltage refers to voltages of up to 1000 volts AC or up to 1500 volts DC. Low voltage refers in particular to voltages that are greater than extra-low voltage, with values of 50 volts AC or 120 volts DC. Low-voltage circuit or network or system refers to circuits with nominal currents or rated currents of up to 125 amperes, more specifically up to 63 amperes. Low-voltage circuits are, in particular, circuits with nominal currents or rated currents of up to 50 amperes, 40 amperes, 32 amperes, 25 amperes, 16 amperes or 10 amperes.The current values mentioned refer in particular to nominal, rated and / or breaking currents, i.e. the maximum current that is normally carried through the circuit or at which the electrical circuit is usually interrupted, for example by a protective device such as a protective switching device, miniature circuit breaker or power breaker. The nominal currents can be further staggered, from 0.5 A to 1 A, 2 A, 3 A, 4 A, 5 A, 6 A, 7 A, 8 A, 9 A, 10 A, etc. up to 16 A. Miniature circuit breakers are long-established overcurrent protection devices used in electrical installation technology in low-voltage circuits. These protect cables from damage caused by heating as a result of excessive current and / or a short circuit. A miniature circuit breaker can automatically switch off the circuit in the event of an overload and / or short circuit. A circuit breaker is a non-automatic safety device.are, in contrast to miniature circuit breakers, intended for currents greater than 125 A, and in some cases even from 63 A. Miniature circuit breakers are therefore simpler and more delicately constructed. Miniature circuit breakers usually have a mounting option for mounting on a so-called top-hat rail (support rail, DIN rail, TH35). Miniature circuit breakers are electromechanically constructed. In a housing, they have a mechanical switching contact or shunt release to interrupt (trip) the electrical current. Typically, a bimetallic protective element or bimetallic element is used for tripping (interruption) in the event of a prolonged overcurrent (overcurrent protection) or thermal overload (overload protection). An electromagnetic release with a coil is used for brief tripping when an overcurrent limit is exceeded or in the event of a short circuit (short-circuit protection). One or moreArc quenching chamber(s) or devices for arc quenching are provided. Furthermore, connection elements for conductors of the electrical circuit to be protected. Protective switching devices with an electronic interruption unit are relatively new developments. These have a semiconductor-based electronic interruption unit. This means that the electrical current flow of the low-voltage circuit is guided via semiconductor components or semiconductor switches, which interrupt the electrical current flow or can be switched to conduction. Protective switching devices with an electronic interruption unit also often have a mechanical isolating contact unit, 202219605 3 in particular with isolating properties in accordance with relevant standards for low-voltage circuits, wherein the contacts of the mechanical isolating contact unit are connected in series to the electronic interruption unit, this means that the current of the circuit to be protectedLow-voltage circuit is routed via both the mechanical isolating contact unit and the electronic interruption unit. The present invention can be used for both low-voltage direct current circuits and low-voltage alternating current circuits. The invention relates in particular to low-voltage alternating current circuits with an alternating voltage, usually with a time-dependent sinusoidal alternating voltage with the frequency f. The time dependence of the instantaneous voltage value u(t) of the alternating voltage is described by the equation: u(t) = U * sin (2π * f * t). Where: u(t) = instantaneous voltage value at time t U = amplitude of the voltage A harmonic alternating voltage can be represented by the rotation of a vector whose length corresponds to the amplitude (U) of the voltage. The instantaneous deflection is the projection of the vector onto a coordinate system. One oscillation period corresponds to onefull rotation of the pointer and its full angle is 2π (2Pi) or 360°. The angular frequency is the rate of change of the phase angle of this rotating pointer. The angular frequency of a harmonic oscillation is always 2π times its frequency, ie: ω = 2π*f = 2π / T = angular frequency of the alternating voltage (T = period of the oscillation) 202219605 4 The angular frequency (ω) is often preferred to the frequency (f), since many formulas in oscillation theory can be represented more compactly using the angular frequency due to the occurrence of trigonometric functions whose period is by definition 2π: u(t) = U * sin(ωt) In the case of angular frequencies that are not constant over time, the term instantaneous angular frequency is also used. For a sinusoidal, in particular time-constant, alternating voltage, the time-dependent value of the angular velocity ω and the time t corresponds to the time-dependent angle φ(t), which is also called the phase angle φ(t)This means that the phase angle φ(t) periodically passes through the range 0…2π or 0°…360°. This means that the phase angle periodically assumes a value between 0 and 2π or 0° and 360° (φ = n*(0…2π) or φ = n*(0°…360°), due to periodicity; abbreviated: φ = 0…2π or φ = 0°…360°). The instantaneous voltage value u(t) therefore means the instantaneous value of the voltage at time t, i.e. in the case of a sinusoidal (periodic) alternating voltage, the value of the voltage at the phase angle φ (φ = 0…2π or φ = 0°…360°, of the respective period). The object of the present invention is to improve a protective switching device of the type mentioned above, in particular to achieve greater flexibility or a new feature for the protective switching device. This object is achieved by a protective switching device with the features of patent claim 1, as well as by a method according to patent claim 15. According to the invention, a protective switching device for protecting an electrical low-voltage circuit,in particular 202219605 5 low-voltage AC circuit, proposed, comprising: - a housing with at least one mains-side connection and at least one load-side connection, both for the low-voltage circuit, - a mechanical isolating contact unit which is connected in series with an electronic interruption unit, wherein the series connection is connected on the one hand to the at least one mains-side connection and on the other hand to the at least one load-side connection, - that the mechanical isolating contact unit is switchable by opening at least one contact to prevent a current flow or closing the at least one contact for a current flow in the low-voltage circuit, - that the electronic interruption unit is switched by semiconductor-based switching elements into a high-resistance state of the switching elements to prevent a current flow or a low-resistance state of the switching elements for current flow inLow-voltage circuit is switchable, - a current sensor unit for determining the current level of the low-voltage circuit, - a control unit connected to the current sensor unit, the mechanical isolating contact unit and the electronic interruption unit, wherein, if current and / or current time limit values are exceeded, the avoidance of a current flow in the low-voltage circuit is initiated, in particular by a high-resistance state of the switching elements of the electronic interruption unit. According to the invention, a control input is provided on the protective switching device. This is connected in particular to the control unit. The protective switching device is designed such that the electronic interruption unit can be switched to a high-resistance or low-resistance state by means of the control input. This has the advantage that a control input is provided with which the electronic interruption unit can be explicitly switchedUsually, only the mechanical isolating contact unit can be switched by a handle accessible on the protective switching device. External (control input) switching of the electronic interruption unit is usually not provided. The invention enables this externally and provides a possibility to expand the functions of the device. Further advantageous embodiments of the invention are specified in the subclaims and in the exemplary embodiment. In an advantageous embodiment of the invention, the mechanical isolating contact unit is assigned to the load-side connection and the electronic interruption unit (EU) is assigned to the mains-side connection. In particular, the mechanical isolating contact unit can be operated by a mechanical handle in order to switch an opening of the at least one contact or a closing of the at least one contact. This has the particular advantage that a structure for a protective switching deviceis provided, in which the protective switching device functions even when the contacts of the mechanical isolating contact unit are open. In an advantageous embodiment of the invention, two mains-side connections and at least one load-side connection are provided. In particular, a mains-side phase conductor connection, a mains-side neutral conductor connection, and a load-side phase conductor connection are provided. This has the particular advantage of providing a structure for a protective switching device in which, on the one hand, a power supply to the protective switching device is provided and, on the other hand, a space-saving design is enabled by only one switched pole. In an advantageous embodiment of the invention, two mains-side connections and two load-side connections are provided. In particular, a mains-side neutral conductor connection, a mains-side phase conductor connection, a load-side neutral conductor connection, and aload-side phase conductor connection is provided. 202219605 7 This has the particular advantage that a structure for a two-pole protective switching device is provided, so that phase and neutral conductors can be connected directly and, for example, additional neutral conductor rails can be omitted. In an advantageous embodiment of the invention, the control input has a, in particular safe, galvanic isolation. In particular, a safe, galvanic isolation between the control input and the control unit. More specifically, between the control input and the low-voltage circuit (voltage of the low-voltage circuit present in the device). Safe galvanic isolation can be realized, for example, by means of an optocoupler or relay. Alternatively, by inductive or capacitive galvanic isolation. This has the particular advantage that the control input can be used universally in a potential-free manner or a safe galvanic isolation from thePhase conductors (or to the control unit). Since the phase conductors (or the control unit) are at mains voltage (e.g. 230 V(AC)) during operation, this galvanic isolation enables safe use of the control input. In particular, this enables protection against electric shock or so-called "voltage carryover" to a connected electrical line and the devices connected there. In the case of voltage carryover, an electrical potential is unintentionally transferred to an electrical line or another device. This has the particular advantage that the protective switching device can be used universally in a potential-free manner and a safe galvanic isolation from the phase conductors (or to the control unit) is provided. In an advantageous embodiment of the invention, the electronic interruption unit can only be switched to a low-resistance state by means of the control input if an enabling conditionis present. In particular, in the case of a high-impedance state of the electronic interruption unit caused by a protective function of the protective switching device, it cannot be switched to the low-impedance state by the control input (in particular at least not within a first time period after becoming high-impedance). The first time period can be in the range of 10 seconds or longer. This has the particular advantage that the basic function of the protective switching device - to provide protection - is not influenced by the control input and, for example, a defective protective switching device (no release condition) cannot be forcibly switched on by the control input, i.e., supply the low-voltage circuit with energy without protection. Furthermore, in the case of a high-impedance state of the electronic interruption unit caused by a protective function of the protective switching device (for example, when / after current and / orCurrent-time limit values) this high-impedance state cannot be changed by the control input, i.e. the low-impedance state can be switched on again forcibly (immediately). So that the protective device can only be switched back to low-impedance after the fault has been acknowledged or after the fault no longer exists. In an advantageous embodiment of the invention, protection device-side checking functions which a) switch an electronic interruption unit in the high-impedance state to the low-impedance state for a first period of time or (and) b) switch an electronic interruption unit in the low-impedance state to the high-impedance state for a second period of time cannot be influenced by the control input (i.e. the checking functions are carried out independently of the (status of the) control input). This has the particular advantage that checking functions of theThe protective switching device is not influenced by the control input, thus ensuring functional reliability, particularly through testing functions (during operation) of the protective switching device. The first time period is, for example, a short time period in the range of µs or ms up to one second, such as 100µs ... 200µs ... 300µs ... 600µs ... 700µs ... 800µs ... 1ms ... 10ms ... 20ms ... 40ms ... 50ms ... 100ms ... 200ms ... 500ms ... 1s (any intermediate value is possible). The second time period is, for example, a short time period in the range of µs or ms up to one second, such as 100µs ... 200µs ... 300µs ... 600µs ... 700µs ... 800µs ... 1ms ... 10ms ... 20ms ... 40ms ... 50ms ... 100ms ... 200ms ... 500ms ... 1s (any intermediate value is possible). In an advantageous embodiment of the invention, the control input can be used to open at least one contact of the mechanical isolating contact unit, in particular it can be configured whether the control input a)electronic interruption unit can be switched to a high-resistance or low-resistance state, or b) at least one contact of the mechanical isolating contact unit can be opened. Alternatively or additionally, for example, one or the other state can be initiated by a (particularly configurable) switching sequence; this can, in particular, be configurable. This has the particular advantage of providing further flexibility and functional expansion of the protective switching device. In an advantageous embodiment of the invention, the control input is accessible from the housing. In particular, the control input has several connection terminals, in particular two or three connection terminals, wherein the connection terminals are connected internally to the protective switching device, in particular to at least one optocoupler or relay contact (generally to a potential-isolating element, for example on an inductive or capacitive basis). 202219605 10 DesFurthermore, this control input provides a wired interface (in particular a two- or three-wire wired communication interface), so that a virtually delay-free signaling through the control input (largely latency-free) is provided. By quasi delay-free is meant direct signaling, i.e. without overhead-related information processing, as occurs, for example, in LAN / WLAN connections, through communication protocols that use, for example, MAC addresses, TCP / IP communication, or OSI communication. This has the particular advantage of providing a simple option for connecting the control input. In an advantageous embodiment of the invention, a display unit connected to the control unit is provided, which has visible display means on the protective switching device for displaying the high-impedance or low-impedance state of the electronicInterruption unit. This has the particular advantage of providing visualization of the state of the electronic interruption unit. In an advantageous embodiment of the invention, the protective switching device is designed such that, when the electronic interruption unit is in a high-impedance state initiated by the control input, this high-impedance state of the electronic interruption unit is established at zero current crossing. Zero current crossing means directly at or near zero current crossing, e.g., at an instantaneous current value that is less than a first current limit, for example, less than 5 amperes ... 1 ampere (any intermediate value is possible; the first current limit depends on the rated current of the low-voltage circuit or protective switching device, for example, 20% ... 15% ... 10% ... 5% ... 1% or less of the rated current). 202219605 11 This has the particular advantage that a quasi-powerlessThis switching is supported and thus the load on the electronic interruption unit, in particular its semiconductor-based switching elements, is reduced. In an advantageous embodiment of the invention, a (first) voltage sensor unit connected to the control unit is provided for determining the voltage level of the low-voltage circuit, in particular so that instantaneous values of the voltage level are available. The protective switching device is designed such that, in the case of a low-resistance state of the electronic interruption unit initiated by the control input, this low-resistance state of the electronic interruption unit is established at the voltage zero crossing. Alternatively or additionally, in the case of a high-resistance state of the electronic interruption unit initiated by the control input, this high-resistance state of the electronic interruption unit is established at the voltage zero crossing. This has theThe particular advantage is that further, virtually powerless switching is supported, thus reducing the load on the electronic interruption unit, in particular its semiconductor-based switching elements. At voltage zero crossing means directly at the voltage zero crossing or in its vicinity, ie, for example, at an instantaneous voltage value that is less than a first voltage limit, for example, less than 10 volts, 25 volts, or 50 volts (any intermediate or smaller value is possible). In an advantageous embodiment of the invention, the protective switching device is designed such that the control input: a) initiates the high-impedance state when a first voltage level is present, or the low-impedance state when a second voltage level is present, or b) initiates the state change of the electronic interruption unit by a third voltage level present for a first period of time, or c) by afor a second period of time, the third voltage level applied changes to the low-resistance state and after a third period of time, which can be adjusted in particular, changes to the high-resistance state. This has the particular advantage that various switching options are available, which are advantageously configurable, for example. In an advantageous embodiment of the invention, the protective switching device is designed such that an acknowledgment of a fault-related high-resistance state of the electronic interruption unit, in particular that the fault-related high-resistance state was initiated by the current and / or current-time limit values in the low-voltage circuit being exceeded, takes place by means of the control input, so that the electronic interruption unit can be switched to the low-resistance state if there is no fault thereafter or automatically changes to the low-resistance state, in particular it is configurable whether the control inputa) the electronic interruption unit can be switched to a high-resistance or low-resistance state, or b) an acknowledgement of a fault-related high-resistance state occurs. This has the particular advantage that an additional functionality of the protective switching device is provided. According to the invention, a corresponding method for a protective switching device for a low-voltage circuit with electronic (semiconductor-based) switching elements with the same and further advantages is claimed. The method for a protective switching device for protecting an electrical low-voltage circuit with: - a housing with at least one mains-side connection and at least one load-side connection, 202219605 13 - a mechanical isolating contact unit connected in series with an electronic interruption unit, wherein the series connection is connected on the one hand to the at least one mains-side connection and on the other hand to the at least one load-side connection- that the mechanical isolating contact unit can be switched by opening at least one contact to prevent a current flow or closing at least one contact for a current flow in the low-voltage circuit, - that the electronic interruption unit can be switched by semiconductor-based switching elements into a high-resistance state of the switching elements to prevent a current flow or a low-resistance state of the switching elements for current flow in the low-voltage circuit, - that the level of the current of the low-voltage circuit is determined and, if current and / or current-time limit values are exceeded, the avoidance of a current flow in the low-voltage circuit is initiated, - that the electronic interruption unit can be switched into a high-resistance or low-resistance state by means of a control input. All embodiments, both in dependent form and related toPatent claims 1 and 15, respectively, as well as referring back only to individual features or combinations of features of patent claims, in particular also a reference of the dependent arrangement claims to the independent method claim (and vice versa), bring about an improvement in a protective switching device, in particular an improvement in functionality, and provide a new concept for a protective switching device. The described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understandable in connection with the following description of the exemplary embodiments, which are explained in more detail in connection with the drawings. 202219605 14 The drawing shows: Figure 1 shows a first representation of a protective switching device, Figure 2 shows a second representation of a protective switching device, Figure 3 shows a representation of a control input, Figure 4 shows a representation of a functional grouping,Figure 5 shows a representation of a first configuration, Figure 6 shows a representation of a second configuration, Figure 7 shows a representation of a third configuration, Figure 8 shows a representation of a fourth configuration. Figure 1 shows a representation of a protective switching device SG for protecting an electrical low-voltage circuit, in particular a low-voltage AC circuit, with a housing GEH, comprising: - a mains-side neutral conductor connection NG, a mains-side phase conductor connection LG, a load-side neutral conductor connection NL, a load-side phase conductor connection LL of the low-voltage circuit; an energy source is usually connected to the mains side Grid, and a consumer is usually connected to the load side Load; - a (two-pole) mechanical isolating contact unit MK with load-side connection points APLL, APNL and mains-side connection points APLG, APNG, wherein a load-side connection point APNL,A load-side connection point APLL is provided for the phase conductor, a mains-side connection point APNG is provided for the neutral conductor, and a mains-side connection point 202219605 15 APLG is provided for the phase conductor. The load-side connection points APNL, APLL are connected to the load-side neutral and phase conductor connections NL, LL, so that the opening of contacts KKN, KKL to prevent a current flow or the closing of the contacts to allow a current flow in the low-voltage circuit can be switched. The mechanical isolating contact unit can also be designed as a single-pole mechanical isolating contact unit, i.e. with one contact, whereby the contact KKL is preferably arranged in the phase conductor L. A neutral conductor N passing through the protective switching device SG is then not provided. - an electronic interruption unit EU, in particular a single-pole one (which in the single-pole version is arranged in particular in the phase conductor L) with a mains-side connection point EUG,which is electrically connected to the mains-side phase conductor connection LG, and a load-side connection point EUL, which is electrically connected or connected to the mains-side connection point APLG of the mechanical isolating contact unit MK, wherein the electronic interruption unit has a high-resistance state of the switching elements to prevent a current flow or a low-resistance state of the switching elements to prevent current flow in the low-voltage circuit by means of semiconductor-based switching elements, - a current sensor unit SI, for determining the level of the current of the low-voltage circuit, which is arranged in particular in the phase conductor L, - a control unit SE, which is connected to the current sensor unit SI, the mechanical isolating contact unit MK and the electronic interruption unit EU, wherein if current and / or current-time limit values are exceeded, a current flow in the low-voltage circuit is preventedis initiated. According to the invention, the protective switching device SG is designed such that a control input CI is provided on the protective switching device SG. The control input CI is connected in particular to the control unit SE. The protective switching device is designed such that the electronic interruption unit EU can be switched to a high-resistance or low-resistance state by means of the control input CI. Furthermore, a first voltage sensor unit SUA connected to the control unit SE can be provided, which determines the voltage level, in particular instantaneous values of the voltage level, of the low-voltage circuit, in particular at the mains-side terminals LG, NG, specifically between the mains-side neutral conductor terminal NG and the mains-side phase conductor terminal LG. The electronic interruption unit EU is advantageously switched to the low-resistance state, in particular via the control input, when the amount ofinstantaneous value of the voltage falls below a first voltage limit, which is in particular less than or equal to 50 volts (or 25 volts or 10 volts). For example, if (at that moment) the electronic interruption unit EU is to be switched to the low-impedance state (switched on) via the control input CI, the switch-on signal is only sent from the control unit SE to the electronic interruption unit (EU) when the instantaneous value of the voltage falls below the first voltage limit, which is in particular less than or equal to 50 volts. This results in a time offset between the moment of the external control signal ESS (switch-on signal) (at the control input CI) and the low-impedance state of the electronic interruption unit EU of up to approximately 10 ms (at a 50 Hz mains frequency). The same applies to the high-impedance switching of the electronic interruption unit EU initiated by the control input CI. When the switch-on signal initiated by the control inputFor high-impedance switching of the electronic interruption unit, the first current limit can be used instead of the first voltage limit. Generally, the mechanical isolating contact unit MK and the electronic interruption unit EU form a series circuit. The series circuit is connected, on the one hand, to at least one mains-side connection and, on the other hand, to at least one load-side connection. The mechanical isolating contact unit MK can advantageously be assigned to the load-side connection, and the electronic interruption unit EU to the mains-side connection, as shown in Figure 1. The mechanical isolating contact unit MK can be operated by a mechanical handle HH to switch the opening or closing of contacts, as with a conventional circuit breaker or miniature circuit breaker (MCB). The control unit SE can have a microcontroller MP (microcontroller unit).(as shown in Figure 2). A second voltage sensor unit SUB connected to the control unit SE can also be provided, which determines the voltage level between the mains-side connection point EUG and the load-side connection point EUL of the electronic interruption unit EU. A measuring impedance ZM can be connected between the mains-side connection points APLG, APNG of the mechanical isolating contact unit MK. The measuring impedance ZM can, for example, be an electrical resistor and / or capacitor. The measuring impedance can also be an inductance. In particular, the measuring impedance can be a series connection or parallel connection of a resistor and / or capacitor and / or inductance. In the example according to Figure 1, the electronic interruption unit EU is single-pole, in the example in the phase conductor. The mains-side connection point APNG for the neutral conductor of the mechanical isolating contact unit MK is connected to theThe protective switching device SG is advantageously designed such that the contacts of the mechanical isolating contact unit MK can be opened, but not closed, by the control unit SE, which is indicated by an arrow from the control unit SE to the mechanical isolating contact unit MK. This means, for example, that in one embodiment the contacts of the mechanical isolating contact unit MK can be opened, but not closed, using the control input CI. The mechanical isolating contact unit MK can be operated by a mechanical handle HH on the protective switching device SG in order to switch a manual opening or closing of the contacts KKL, KKN. The mechanical handle HH shows (especially by a mechanical connection betweenContacts and handle) indicates the switching state (open or closed) of the contacts of the mechanical isolating contact unit MK on the protective switching device. The mechanical isolating contact unit MK is advantageously designed such that (manual) closing of the contacts by the mechanical handle is only possible after an enable, in particular an enable signal. This is also indicated by the arrow from the control unit SE to the mechanical isolating contact unit MK. This means that the contacts KKL, KKN of the mechanical isolating contact unit MK can only be closed by the handle HH when the enable or the enable signal (from the control unit) is present. Without the enable or the enable signal, the handle HH can be operated, but the contacts cannot be closed ("permanent slip"). The protective switching device SG has a power supply NT, for example a power supply unit. In particular, the power supply NT is responsible for theA control unit SE is provided, which is indicated by a connection between the power supply NT and the control unit SE in Figure 1. The power supply NT is (on the other hand) connected to the mains-side neutral conductor connection NG and the mains-side phase conductor connection 202219605 19 LG. A fuse SS, in particular a safety fuse, and / or a switch can advantageously be provided in the connection to the mains-side neutral conductor connection NG (and / or phase conductor connection LG). In the case of a purely single-pole protective switching device, the power is supplied by an external power source / additional connections. High-resistance means a state in which only a negligible current flows. In particular, high-resistance means resistance values greater than 1 kiloohm, preferably greater than 10 kiloohms, 100 kiloohms, 1 megaohm, 10 megaohms, 100 megaohms, 1 gigaohm or greater. Low resistance means a state in which the resistance on theThe current value specified in the circuit breaker could flow. In particular, low-resistance refers to resistance values that are less than 10 ohms, preferably less than 1 ohm, 100 milliohms, 10 milliohms, 1 milliohm, or less. In a first variant, the mechanical isolating contact unit MK can interrupt single-pole. This means that only one conductor (of the two / several conductors), in particular the active conductor or phase conductor, is interrupted, i.e., it has a mechanical contact. The neutral conductor is then contact-free, i.e., the neutral conductor is directly connected. In a second variant of the mechanical isolating contact unit MK, the neutral conductor also has mechanical contacts, as shown in Figure 1. The mechanical isolating contact unit MK specifically refers to a (standard-compliant) isolating function, implemented by the isolating contact unit MK. The isolating function includes the following points: -Minimum air gap according to the standard (minimum distance between the contacts), -(mechanical)Contact position indication of the contacts of the mechanical isolating contact unit, trip-free operation, i.e., an actuation to interrupt the contacts of the mechanical isolating contact unit by the 202219605 20 handle or control unit is always possible, so that no (permanent) blocking of the contacts in the closed state by the handle is possible. Furthermore, the standard-compliant isolating function can include the ability to lock the isolating contact unit or the handle in the switched on or off state. With regard to the minimum air gap between the contacts of the isolating contact unit, this is essentially voltage-dependent. Other parameters are the degree of contamination, the type of field (homogeneous, inhomogeneous), and the air pressure or the altitude above sea level. There are corresponding regulations or standards for these minimum air gaps or creepage distances. These regulations specify, for example, theMinimum clearance for an inhomogeneous and a homogeneous (ideal) electric field depending on the degree of contamination. The surge voltage withstand capability is the resistance when a corresponding surge voltage is applied. Only when this minimum length (minimum distance) is present does the isolating contact unit or protective switching device exhibit an isolating function (isolating property). For the purposes of the invention, the DIN EN 60947 and IEC 60947 standards series are relevant for the isolating function and its properties, to which reference is made here. The isolating contact unit is advantageously characterized by a minimum clearance of the open isolating contacts in the OFF position (open position, open contacts) depending on the rated surge voltage withstand capability and the degree of contamination. The minimum clearance is in particular between (at least) 0.01 mm and 14 mm. In particular, the minimum clearance is advantageouslybetween 0.01 mm at 0.33 kV and 14 mm at 12 kV, 202219605 21 particularly for pollution degree 1 and particularly for inhomogeneous fields. The minimum clearance can advantageously have the following values: The pollution degrees and field types correspond to those defined in the standards. This advantageously makes it possible to achieve a standard-compliant protective switching device dimensioned according to the rated impulse withstand voltage. A mechanical isolating contact unit does not, in particular, mean a relay contact. Figure 2 shows an illustration according to Figure 1, with additional or different units being shown. In Figure 2, the power supply NT is part of the control unit SE. Furthermore, a (particularly wireless) 202219605 22 communication unit COM is provided, which is connected to the control unit SE or is part of it. Furthermore, a display unit AE is provided. The display unit AE can be used as a combined display and input unitbe designed. The display unit AE (display and input unit) is connected to the control unit SE or is a part of it. The display unit has visible display means on the protective switching device, in particular for displaying the high-resistance or low-resistance state of the electronic interruption unit EU. The electronic interruption unit EU is, according to Figure 2, a part of the control unit SE. According to Figure 2, the control unit SE can have a microcontroller MP (microcontroller unit). The microcontroller can have various functions or routines / procedures, such as a configuration function KF, a switching logic function SF, and a protection function PF. The protective switching device SG, for example, operates in principle in such a way that when the contacts of the mechanical isolating contact unit and the low-resistance interruption unit are closed and - when a determined current exceeds a first current value, in particular thatthe first current value is exceeded for a first time limit, the electronic interruption unit EU becomes high-resistance and the mechanical isolating contact unit MK remains closed, or / and - (or / and) if the detected current exceeds a higher second current value, in particular for a second time limit, the electronic interruption unit EU becomes high-resistance and the mechanical isolating contact unit MK is opened, or / and - if the detected current exceeds an even higher third current value, the electronic interruption unit becomes high-resistance and the mechanical isolating contact unit MK is opened. 202219605 23 The invention is described in more detail below, partly in different terms. In novel electronic protective switching devices, contacts (of a mechanical isolating contact unit) are combined with an electronic switch / semiconductor-based switching elements (of an electronic interruption unit)The controllability of these switching elements via a (galvanically isolated) control input CI is a novel way of expanding the functions of the protective switching device. At the same time, the invention ensures that the controllability of the switching elements / electronic interruption unit does not impair the safety-relevant protective functions of the protective switching device. The control unit SE can switch the electronic interruption unit EU to a high-resistance or low-resistance state, i.e., switch it on and off, as well as open the contacts (the contact) of the mechanical isolating contact unit. Furthermore, a handle (for opening and closing the isolating contact unit), a current measurement, advantageously a voltage measurement, and a power supply are provided. The protective switching device can perform various protective functions PF, such as short-circuit protection, overload protection, residual current protection, fire protection,Overvoltage protection, undervoltage protection, overtemperature protection. Overload protection is, for example, the exceeding of first current and / or current-time limit values. Short-circuit protection is, for example, the exceeding of second (higher) current and / or current-time limit values. Residual current protection is, for example, the exceeding of residual current limits (e.g., 30 mA). Fire protection is, for example, the detection of serial arc faults in the low-voltage circuit. The same applies to overvoltage protection, undervoltage protection, and overtemperature protection. 202219605 24 According to the invention, a control input CI, in particular a galvanically isolated one, is added. The switching state of the electronic interruption unit EU can be controlled via this control input CI. Since the electronic interruption unit EU is required in particular for executing protective functions PF, the control unit SE issues a signal fromThe control input CI for switching the electronic interruption unit EU to low impedance is only passed on to the electronic interruption unit EU if none of the stored protective functions PF has detected an error, i.e., a release condition exists. In particular, if an error is detected, i.e., if the electronic interruption unit EU is in the high impedance state, the control input cannot change this state (i.e., cannot switch to low impedance). This means that the electronic interruption unit EU can only be switched to the low impedance state via the control input CI if a release condition exists. In particular, if the electronic interruption unit EU is in a high impedance state caused by a protective function PF of the protective switching device, it cannot be switched to the low impedance state via the control input. A detected error in the protective switching device refers, in particular, to a device error, such asfor example, a defective current sensor unit, defective interruption unit, overtemperature. Furthermore, this can also be the case with external faults, such as overvoltage or undervoltage (effective value of the voltage below the threshold for a certain period of time). Furthermore, this can affect the normal protective functions PF, so that after the current and / or current time limit values are exceeded and the current flow of the low-voltage circuit is avoided, an immediate "forced" low-resistance switching via the control input CI is not possible or not immediately possible. The same applies to other internal device functions / circuit breaker-side testing functions, e.g., for device diagnostics or inrush handling. Ie 202219605 25 circuit breaker-side testing functions that a) switch an electronic interruption unit EU in the high-resistance state to the low-resistance state for an initial period of time or (and) b) switch an electronic interruption unit EU in the low-resistance stateSwitching the electronic interruption unit EU in the fault state to the high-impedance state for a second period of time cannot be influenced by the control input. These short switching operations can be used, for example, to test the electronic interruption unit or to check the functionality of the current sensor unit. These short switching operations are prioritized by the control unit SE or the switching logic function SF, so that an (external) control signal ESS at the control input CI cannot prevent these short switching operations. The controllability of the electronic interruption unit EU (or its switching elements) is therefore only possible via the control input CI if the protective switching device is in a fault-free state and / or no fault has been detected at the load-side connection(s) (at the load output) (a release condition exists). This task is performed by the switching logic function SF. The control input CI can thereforedo not directly access the electronic interruption unit (or its switching elements) for control purposes, but only send a signal ESSI to the switching logic function SF to switch the electronic interruption unit on or off. The switching logic function SF thus ensures that the protective functions PF can always have priority over the electronic interruption unit. This applies not only to the protective functions PF of the protective switching device, but also to the testing functions of the protective switching device, which in particular check the switchability of the electronic interruption unit, for example, by switching it on or off for the (short) first or second time period. 202219605 26 Figure 3 shows the basic structure of a galvanically isolated control input CI in conjunction with an external control unit ESE. Figure 3 shows a control input CI that is accessible from the housing. It has several connection terminals, in the exampleTwo connection terminals AK1, AK2, whereby the two connection terminals AK1, AK2 are connected internally to at least one optocoupler OPK. In the example, the optocoupler OPK is connected on the one hand to a resistor R1, whereby the resistor R1 is also connected to a voltage of 3.3V (iB positive connection to an internal voltage of 3.3 volts). The connection between resistor R1 and optocoupler OPK is accessible {0V; 3.3V} {0.1} and, in the example, supplies an internal control signal ESSI equivalent to the external control signal ESS (and galvanically isolated) for further processing in the protective switching device. The other connection of the optocoupler OPK is connected to the other connection of the 0V voltage (iB ground connection). The two terminals AK1, AK2 are connected to the outside of the housing with a two-wire cable comprising a first conductor LT1 and a second conductor LT2. The two-wire cable is also connected to aexternal control unit ESE. The external control unit ESE optionally provides a 24V voltage signal, which is used to control the optocoupler via the control input CI to make the electronic interruption unit (OPK) high- or low-impedance. This means that an optocoupler OPK with appropriate galvanic isolation is provided. An external (remote) control unit ESE sends a voltage to transmit a control signal ESS. Instead of the optocoupler, a relay or other element for galvanic isolation can also be provided or used. Such as elements based on capacitive or inductive galvanic isolation. 202219605 27 Figure 4 shows a further embodiment of the invention, a functional grouping for the microcontroller MP. The microcontroller MP has a connection to the control input CI, to which a signal from the control input SCI is fed. This signal is fed to aControl signal configuration unit CSC. Optionally, it can be configured here, for example, that the mechanical isolating contact unit MK is opened by an opening signal TRIP (open contact / contacts) via the control input. The signal from the control input is then fed to the switching logic function SF. The switching logic function is further connected to protective functions PF, in the example with an internal protective function IPF, for the internal checking and reporting of the fault-free condition of the protective switching device, and an external protective function CPF, which monitors the low-voltage circuit and reports an overcurrent event, short circuit, etc. in the low-voltage circuit. If the protective switching device has no internal fault, which is reported by the internal protective function IPF, and no external fault is present in the low-voltage circuit to be protected, which is reported by the external protective function CPF, both messages are sent to theIf the switching logic function SF is active, an enabling condition is present and the electronic interruption unit can be switched to a low-resistance or high-resistance state via the control input (connection of the switching logic function SF with the electronic interruption unit EU (arrow pointing there). The switching logic function SF ensures in the protective switching device that the protective functions PF, IPF, CPF, which depend on the controllability of the electronic interruption unit EU, can always switch it safely when needed. If a protective function is active, the electronic interruption unit cannot be controlled via the control input. If no protective state is active (enabling condition), controllability is released again for the electronic interruption unit via the control input. 202219605 28 The same principle applies to internal device functions / internal protective function IPF. These internal protective functions IPF take effectalso applies to the electronic interruption unit. This can, for example, only be a short switching operation for a device diagnostic function. If this function is executed, control via the control input is not possible for this moment. The control signal configuration unit CSC can be used to configure what is / should be done with the (digital) control signal. For example, the electronic interruption unit EU can be controlled, or the mechanical isolating contact unit, or both. This can be achieved through different levels of the external control signal ESS, time offsets, or sequences. Examples of parameterization and configuration are listed below. 1.) Simple on / off switching The electronic interruption unit is low-resistance when the external control signal ESS is 1 and high-resistance when the external control signal ESS is 0. 2.) Simple on / off switching (inverted) ElectronicThe interruption unit has a high impedance when an external control signal ESS of 1 is applied and a low impedance when an external control signal ESS of 0 is applied. [1 or 2 - in general: the high impedance state is initiated when a first voltage level is applied, or the low impedance state is initiated when a second voltage level is applied; both voltage levels can be identical] 3.) Impulse switching The electronic interruption unit changes state when there is a rising (or falling signal edge) at the control input. This means that the state change of the electronic interruption unit is initiated by a third voltage level applied for an initial period of time. 202219605 29 4.) Impulse switching with timer The electronic interruption unit changes to the on state when there is a rising (or falling signal edge) at the control input. The electronic interruption unit automatically changes to the high impedance state after an (adjustable) time.This means that when a third voltage level is applied for a second period of time, the electronic interruption unit switches to the low-impedance state, and after a third period of time, which can be adjusted, the electronic interruption unit switches to the high-impedance state. 5.) Time-delayed ON: The electronic interruption unit switches as in point 1 or 2, but with an adjustable ON delay. 6.) Time-delayed OFF: The electronic interruption unit switches as in point 1 or 2, but with an adjustable OFF delay. Further parameterization options are: 7.) Only opening of the contacts of the mechanical isolating contact unit. The isolating contact is opened, for example, upon a change in the edge of the control signal (or a signal sequence). This is shown schematically in Figure 5. Figure 5 shows a parameterization configuration in which the external protection function can control three states. A1 = mechanical isolating contact unitContact(s) opened, electronic interruption unit high-resistance S1 = mechanical isolating contact unit Contact(s) closed, electronic interruption unit high-resistance E1 = mechanical isolating contact unit Contact(s) closed, electronic interruption unit low-resistance The protective switching device is configured in such a way that at least one contact of the 202219605 30 mechanical isolating contact unit MK is opened by means of the control input CI. This means that the external / internal control signal ESS / ESSI causes the state A1. Figure 6 shows a representation according to Figure 5, with the difference that the external / internal control signal ESS / ESSI causes a simple on / off switching, ie low-resistance / high-resistance state of the electronic interruption unit, by means of the switching logic function SF, whereby a high-resistance state occurs when a "positive", logical one control signal ESS / ESSI is present, which is indicated by state 1 in Figure 6, and when notapplied control signal ESS / ESSI, i.e. logic zero, a low-impedance state is to be initiated, which is indicated by the state 0 in Figure 6. Figure 7 shows a representation according to Figure 6, with the difference that it is indicated that the protective switching device is designed or configured in such a way that both the electronic interruption unit EU can be switched between high-impedance / low-impedance states by the control signal ESS / ESSI, for example by a logic zero or one state, alternatively by a first sequence, i.e. sequence of zero / one states. On the other hand, however, the contact(s) of the mechanical isolating contact unit can also be opened, for example by a second sequence SEQB. In the example, the switching of the mechanical isolating contact unit is detected by the control signal configuration unit CSC. This means that the electronic interruption unit EU can be switchedbetween high-impedance / low-impedance. At the same time, the contact / contacts of the mechanical isolating contact unit can be opened via a (switching) sequence stored in the protective switching device. Figure 8 shows a representation according to Figures 5 to 7, with the difference that it is indicated that the 202219605 31 protective switching device is designed in such a way that an acknowledgement of a fault condition occurs via the control signal ESS / ESSI. This means that if the protective switching device is in state S1 due to the current and / or current time limit values being exceeded, this state can be acknowledged and reset via the control input CI. The protective switching device can thus be switched from state S1 to state E1 after a fault (when the fault has cleared up again). This can be done remotely; the device does not have to be switched to state E1 on site. This means that the protective switching device SG can be designed in such a way that by means of theControl input CI is used to acknowledge a fault-related high-resistance state of the electronic interruption unit, in particular that the fault-related high-resistance state was initiated by exceeding current and / or current-time limit values in the low-voltage circuit, so that the electronic interruption unit can be switched to the low-resistance state if the circuit is subsequently free of faults or automatically switches to the low-resistance state, in particular that it is configurable whether, by means of the control input a) the electronic interruption unit (EU) can be switched to a high-resistance or low-resistance state or b) an acknowledgement of a fault-related high-resistance state takes place. Furthermore, the protective switching device can be designed such that the control input CI: a) initiates the high-resistance state when a first voltage level is present or the low-resistance state when a second voltage level is present or b) bya third voltage level applied briefly (e.g. less than 1 second) changes the state. More specifically, a third voltage level applied briefly (e.g. less than 1 second) changes to the low-impedance state 202219605 32 and a subsequent third voltage level changes back to the high-impedance state. The display unit on the protective switching device has visible display means for displaying (showing) the high-impedance or low-impedance state of the electronic interruption unit EU, e.g. by means of an LED display. The contact position of the mechanical isolating contact unit is displayed by the handle; this display by the handle does not show the switching state of the electronic interruption unit. In particular, the switching state of the electronic interruption unit should be displayed when the switching state has been changed / switched on or off via the control input CI.Although the invention has been illustrated and described in detail by the embodiment, the invention is not limited by the disclosed examples and other variations can be derived therefrom by a person skilled in the art without departing from the scope of the invention.
Claims
202219605 33 Patent Claims 1. Protective switching device (SG) for protecting an electrical low-voltage circuit, comprising: - a housing (GEH) with at least one mains-side connection and at least one load-side connection, - a mechanical isolating contact unit (MK) connected in series with an electronic interruption unit (EU), wherein the series connection is connected on the one hand to the at least one mains-side connection and on the other hand to the at least one load-side connection, - that the mechanical isolating contact unit (MK) can be switched by opening at least one contact to prevent a current flow or closing the at least one contact for a current flow in the low-voltage circuit,- that the electronic interruption unit (EU) can be switched by semiconductor-based switching elements into a high-resistance state of the switching elements to prevent a current flow or a low-resistance state of the switching elements to allow current flow in the low-voltage circuit, - a current sensor unit (SI) for determining the level of the current in the low-voltage circuit, - a control unit (SE) connected to the current sensor unit (SI), the mechanical isolating contact unit (MK) and the electronic interruption unit (EU), whereby if current and / or current time limit values are exceeded, the avoidance of a current flow in the low-voltage circuit is initiated, - that a control input (CI) is provided on the protective switching device (SG), - that the protective switching device is designed in such a way,that the electronic interruption unit (EU) can be switched to a high-resistance or low-resistance state by means of the control input (CI).
2. Protective switching device (SG) according to claim 1, characterized in that 202219605 34 that the mechanical isolating contact unit (MK) is assigned to the load-side connection and the electronic interruption unit (EU) is assigned to the mains-side connection, in particular that the mechanical isolating contact unit (MK) can be operated by a mechanical handle to switch an opening of contacts or a closing of the contacts.
3. Protective switching device (SG) according to claim 1 or 2, characterized in that two mains-side connections and at least one load-side connection are provided.
4. Protective switching device (SG) according to claim 1 or 2, characterized in that two mains-side connections and two load-side connections are provided.
5. Protective switching device (SG) according to one of the preceding claims, characterized in that the control input (CI) has a, in particular safe, galvanic isolation. 6.Protective switching device (SG) according to one of the preceding patent claims, characterized in that the electronic interruption unit (EU) can only be switched to a low-resistance state by means of the control input if a release condition exists, in particular that in the case of a high-resistance state of the electronic interruption unit (EU) caused by a protective function of the protective switching device, said unit cannot be switched to the low-resistance state by means of the control input.
7. Protective switching device (SG) according to one of the preceding patent claims, characterized in that the checking functions on the protective switching device side, which... 202219605 35 a) switch an electronic interruption unit (EU) in the high-resistance state to the low-resistance state for a first period of time, or b) switch an electronic interruption unit (EU) in the low-resistance state to the high-resistance state for a second period of time, are not influenced by the control input.
8. The protective switching device (SG) according to one of the preceding claims, characterized in that the at least one contact of the mechanical isolating contact unit (MK) can be opened by means of the control input, in particular that it is configurable whether the control input a) switches the electronic interruption unit (EU) to a high-resistance or low-resistance state, or b) opens the at least one contact of the mechanical isolating contact unit (MK). 9.Protective switching device (SG) according to one of the preceding patent claims, characterized in that the control input is accessible on the housing side, in particular has a plurality of connection terminals, in particular two or three connection terminals, wherein the connection terminals are connected internally to at least one optocoupler.
10. Protective switching device (SG) according to one of the preceding patent claims, characterized in that a display unit connected to the control unit (SE) is provided, which has visible display means on the protective switching device for displaying the high-resistance or low-resistance state of the electronic interruption unit (EU). 202219605 36 11. Protective switching device (SG) according to one of the preceding patent claims, characterized in that the protective switching device is designed such that, when a high-impedance state of the electronic interruption unit is initiated by the control input (CI), this high-impedance state of the electronic interruption unit is established upon current zero crossing. 12.Protective switching device (SG) according to one of the preceding patent claims 1 to 10, characterized in that a first voltage sensor unit (SUA) connected to the control unit (SE) is provided for determining the voltage level of the low-voltage circuit, in particular so that instantaneous values of the voltage level are available, that the protective switching device is designed such that, in the case of a low-resistance state of the electronic interruption unit initiated by the control input (CI), this low-resistance state of the electronic interruption unit is established at the voltage zero crossing and / or that, in the case of a high-resistance state of the electronic interruption unit initiated by the control input (CI), this high-resistance state of the electronic interruption unit is established at the voltage zero crossing. 13.Protective switching device (SG) according to one of the preceding patent claims, characterized in that the protective switching device is designed such that the control input (CI): a) initiates the high-impedance state when a first voltage level is applied or the low-impedance state when a second voltage level is applied or b) by a third voltage level applied for a first period of time. 202219605 37 voltage level initiates the state change of the electronic interruption unit or c) by a third voltage level applied for a second time period, a change of the electronic interruption unit to the low-resistance state is initiated and after a third time period, in particular an adjustable one, the electronic interruption unit changes to the high-resistance state. 14.Protective switching device (SG) according to one of the preceding patent claims, characterized in that the protective switching device (SG) is designed such that an acknowledgment of a fault-related high-resistance state of the electronic interruption unit, in particular that the fault-related high-resistance state was initiated by the current and / or current-time limit values in the low-voltage circuit being exceeded, takes place by means of the control input (CI), so that the electronic interruption unit can be switched to the low-resistance state if there is subsequently no fault or automatically switches to the low-resistance state, in particular that it is configurable whether, by means of the control input, a) the electronic interruption unit (EU) can be switched to a high-resistance or low-resistance state or b) an acknowledgment of a fault-related high-resistance state takes place. 15.Method for a protective switching device (SG) for protecting an electrical low-voltage circuit with: - a housing (GEH) with at least one mains-side connection and at least one load-side connection, - a mechanical isolating contact unit (MK) which is connected in series with an electronic interruption unit (EU), wherein the series connection is connected on the one hand to the at least one mains-side connection and on the other hand to the at least one load-side connection. 202219605 38 - that the mechanical isolating contact unit (MK) can be switched by opening contacts to prevent a current flow or by closing the contacts to allow a current flow in the low-voltage circuit, - that the electronic interruption unit (EU) can be switched by semiconductor-based switching elements into a high-resistance state of the switching elements to prevent a current flow or a low-resistance state of the switching elements to allow current flow in the low-voltage circuit, - that the level of the current in the low-voltage circuit is determined and, if current and / or current-time limit values are exceeded, avoidance of a current flow in the low-voltage circuit is initiated, - that the electronic interruption unit (EU) can be switched to a high-resistance or low-resistance state by means of a control input (CI). 16.Method for a protective switching device (SG) according to patent claim 15, characterized in that the electronic interruption unit (EU) is only switched to a low-resistance state by means of the control input when a release condition exists, in particular that in the case of a high-resistance state of the electronic interruption unit (EU) caused by a protective function of the protective switching device, this cannot be switched to the low-resistance state by the control input.
17. Protective switching device (SG) according to patent claim 15 or 16, characterized in that checking functions on the protective switching device which a) switch an electronic interruption unit (EU) in the high-resistance state to the low-resistance state for a first period of time or b) switch an electronic interruption unit (EU) in the low-resistance state to the low-resistance state for a second period of time. 202219605 39 high-impedance state, not influenced by the control input.