Standard-compliant protective switching device and procedure

Abstract

The invention relates to a protective switching device for low-voltage alternating current circuits, comprising: - a mechanical isolating contact unit connected in series with an electronic interruption unit, the series circuit being 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, - a current sensor unit for determining the current level of the low-voltage AC circuit, - a control unit connected to the current sensor unit, the mechanical isolating contact unit and the electronic interruption unit, whereby if specific tripping current time limit values ​​forming a tripping curve are exceeded, the avoidance of a current flow is initiated, - that a standard for electrical installation material specifies current-time limit values ​​for tripping, so that a current flow in the low-voltage alternating current circuit must be avoided, and current-time limit values ​​for non-tripping, so that a current flow in the low-voltage alternating current circuit must be maintained, which identify a tripping range, - that the specific tripping current time limits are within the tripping range, - that the protective switching device is designed in such a way that at least one first trigger curve and one second trigger curve can be selected within the trigger range, so that a different triggering behavior can be selected within a normatively designated trigger range.

Description

[0001] Regardless of the grammatical gender of a particular term, persons with male, female or other gender identity are included.

[0002] The invention relates to the technical field of a standard-compliant (standard-based) protective switching device for line protection for a low-voltage AC circuit and a method for a standard-compliant (standard-based) protective switching device for line protection for a low-voltage AC circuit.

[0003] Low voltage refers to voltages of up to 1000 volts AC or up to 1500 volts DC. Low voltage refers in particular to voltages greater than extra-low voltage, with values ​​of 50 volts AC or 120 volts DC.

[0004] A low-voltage circuit, network, or system refers to circuits with nominal or rated currents of up to 125 amps, more specifically up to 63 amps. A low-voltage circuit refers in particular to circuits with nominal or rated currents of up to 50 amps, 40 amps, 32 amps, 25 amps, 16 amps, or 10 amps. 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, circuit breaker, or power switch. The rated 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.

[0005] Miniature circuit breakers are long-established overcurrent protection devices used in low-voltage electrical circuits. They protect cables from damage caused by overheating due to excessive current and / or short circuits. A miniature circuit breaker can automatically disconnect the circuit in the event of an overload and / or short circuit. A miniature circuit breaker is a non-self-resetting fuse element. Miniature circuit breakers and their properties are defined, for example, in the standard DIN EN 60898 "Electrical installation equipment - Circuit breakers for household and similar purposes."

[0006] Unlike miniature circuit breakers, circuit breakers are designed for currents greater than 125 A, and in some cases even as low as 63 A. Circuit breakers are constructed differently than miniature circuit breakers. Circuit breakers and their properties are defined, for example, in the standard DIN EN 60947 "Low-voltage switchgear and controlgear."

[0007] In contrast to circuit breakers, miniature circuit breakers have a simpler and more delicate design. Miniature circuit breakers typically have a mounting option for mounting on a so-called top-hat rail (DIN rail, TH35).

[0008] Miniature circuit breakers are electromechanically constructed. They contain a mechanical switching contact or shunt release within a housing to interrupt (trip) the electrical current. Typically, a bimetallic protective element or bimetallic element is used to trip (interrupt) the circuit 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 more arc-quenching chambers or arc-quenching devices are provided. Furthermore, connection elements for conductors of the electrical circuit to be protected are used.

[0009] The tripping behavior of electromechanical circuit breakers is determined by the mechanical components they contain, such as bimetal strips (overload protection) and electromagnetic releases (e.g. trip coils or magnetic releases) (short-circuit protection). Tripping behavior refers to the current at which and after which time the circuit breaker automatically interrupts (opens) the circuit. The design of these electromechanical components defines the tripping behavior of the protective device, which is determined during production. According to standards, a circuit breaker has a tripping behavior within a tripping range (trip characteristic) specified by the standard. This tripping behavior cannot be changed or adapted, particularly after the circuit breaker has been installed.This is because the electrical planning takes into account the tripping behavior (tripping characteristic) of the miniature circuit breaker according to the standard for dimensioning the low-voltage circuit. Changing the tripping characteristic could result in a cable cross-section (conductor cross-section) specified and installed in the electrical planning being no longer sufficient, and thus the safety of the cable (of the low-voltage circuit) no longer meeting the standard requirements.

[0010] Miniature circuit breakers according to the DIN EN 60898 standard have a tripping range (tripping characteristic). In general, miniature circuit breakers are differentiated according to their tripping range in addition to their rated current and design. Currently, standardized tripping range types (tripping characteristic types) are marked with capital letters. There are, for example, standardized tripping characteristic types B, C, D, or manufacturer-specific tripping characteristics such as A, E, K, or Z. For these manufacturer-specific tripping characteristics, the manufacturer tests and guarantees tripping within the range applicable to the characteristic. The electrical planner can use this to design (determine) the cross-section of the electrical cable in the low-voltage circuit and the appropriate line protection provided by an appropriate miniature circuit breaker.

[0011] A type B circuit breaker is a commonly used circuit breaker (in Germany). It must have a rated current I n of, for example, 10 A or 16 A. This is then referred to as a "B10" or "B16 line protection device" (or "B16 circuit breaker"). This means that, for example, a load current of 16 A must always be able to be handled by a B16 line protection device for an unlimited period of time.

[0012] The exemplary tripping ranges (tripping characteristics) specified in the standard serve to cover the response thresholds of the miniature circuit breakers resulting from the electromechanically determined design => and the resulting tolerance limits => and consequently, the resulting response thresholds, in a practically standard-compliant manner. Thus, miniature circuit breakers within a tripping range (tripping characteristic) always exhibit slightly different tripping behavior (due to (tolerance) deviations in the electromechanically determined design). This logically applies both to miniature circuit breakers from different manufacturers and to miniature circuit breakers from the same manufacturer, or even from the same production facility. The miniature circuit breakers always (must) comply with the tripping characteristic / tripping range specified in the standard (or manufacturer's specifications).

[0013] A miniature circuit breaker always has exactly one tripping range (a tripping characteristic) that cannot be changed. For example, a type B miniature circuit breaker only has the type B tripping range according to the standard. This cannot be changed. This enables reliable planning of the electrical installation by specifying corresponding types with defined behavior in the planned electrical installation. Furthermore, the safety device's operability and usability by non-professionals are ensured.

[0014] Circuit breakers are also electromechanical in design. Circuit breakers contain mechanical switching contacts within a housing to interrupt (trip) the electrical current. Typically, they contain a current measuring device connected to an electronic trip unit (ETU). Alternatively, thermo-magnetic trip units (TMTU) (particularly with bimetal and magnetic releases) are also known for circuit breakers. The (electronic) trip unit opens the switching contacts when current-time limit values ​​are exceeded. The current-time limit values ​​are permanently set in the electronic trip unit. One or more arc quenching chambers or arc quenching devices are provided. Connection elements for conductors of the electrical circuit to be protected are also provided.

[0015] According to the standard, circuit breakers do not have a tripping characteristic or tripping range. The tripping characteristic must be designed or calculated as part of the electrical planning. The correct setting of the tripping characteristic must then be carried out by a suitably trained specialist during installation or commissioning of the circuit breaker. In this context, one also speaks of "non-layperson operability." This means that a layperson is not permitted to operate or adjust the device. However, a tripping characteristic with specific current-time limit values ​​must be adjustable. The tripping characteristic can be adjusted over a range that can be quite wide under certain circumstances. This setting may only be carried out by trained electrical personnel (instructed specialists).Operation and use of circuit breakers by non-professionals (untrained persons) is not intended and is also not permitted (high currents in circuit breakers, which can lead to massive damage to property and personal injury if improperly adjusted and the tripping behavior is incorrect).

[0016] The object of the present invention is to improve a circuit breaker of the type mentioned above or a protective switching device, in particular to achieve greater flexibility with regard to the tripping behavior.

[0017] This object is achieved by a protective switching device having the features of patent claim 1 and by a method according to patent claim 13.

[0018] According to the invention, a protective switching device for standard-compliant line protection for low-voltage alternating current circuits is proposed, comprising: - a housing with at least one mains-side connection and at least one load-side connection, - a mechanical isolating contact unit connected in series with an (optional) electronic interruption unit, the series connection being 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 to allow a current flow in the low-voltage alternating current circuit, - that the (optional) electronic interruption unit can be switched by semiconductor-based switching elements into a high-resistance state of the switching elements to prevent current flow or a low-resistance state of the switching elements to allow current flow in the low-voltage AC circuit, - a current sensor unit for determining the current level of the low-voltage AC circuit, - a control unit connected to the current sensor unit, the mechanical isolating contact unit and the (optional) electronic interruption unit, whereby, if specific tripping current time limit values ​​forming a tripping curve are exceeded, the avoidance of a current flow is initiated, in particular by the (optional) electronic interruption unit (of the low-voltage AC circuit), - that a standard for electrical installation material, in particular for circuit breakers, specifies a tripping range characterized by current-time limit values ​​(current-time limit values ​​mean time-current limit values ​​according to the standard, usually these are standard-relevant test points) (i.e. the tripping range is characterized (or limited) by singular test points (current-time limit values), - that one tripping range is limited by (upper) current-time limits of tripping, so that a current flow in the low-voltage AC circuit must be avoided, and (lower) current-time limits of non-tripping, so that a current flow must be maintained in the low-voltage AC circuit, is marked, - that the specific tripping current time limits lie within the tripping range (i.e., for example, that the specific tripping current time limits lie (exclusively) between the tripping current time limits and the non-tripping current time limits) (so that if the specific tripping current-time limit values, which in particular form a tripping curve, are exceeded, a trip usually occurs (if they are undershot, no tripping occurs), so that a current flow prevention of the low-voltage circuit is initiated,) - that the protective switching device is designed in such a way that for one triggering range at least one first triggering curve and one second triggering curve can be selected within the one triggering range, so that a different tripping behavior can be selected within a normatively designated tripping range. This means that the protective switching device has two tripping curves, so that either the first tripping curve (with (first) specific current-time limit values) or the second tripping curve (with (second) specific current-time limit values) triggers a trip, i.e., a current flow (in the low-voltage AC circuit to be protected by the protective switching device) is prevented within the tripping range.

[0019] The first tripping curve can, for example, have initial specific current-time limit values ​​that are close to the current-time limit values ​​for tripping or are (approximately) equal to the current-time limit values ​​for tripping. Thus, the protective switching device in the tripping range only trips when the required tripping is almost reached or (just before) the standard-based tripping is reached. This achieves a high level of supply reliability, since short-term exceedances within the tripping range do not yet lead to a current-preventing trip.

[0020] The second tripping curve can, for example, have second specific current-time limit values ​​that are close to the current-time limit values ​​for non-tripping or (approximately) equal to the current-time limit values ​​for non-tripping. Thus, the protective switching device trips in the tripping range shortly after leaving or upon leaving the (safe) current flow required by the standard. This achieves a high level of safety, since even brief or minor exceedances of the tripping range cause tripping to prevent current flow.

[0021] The tripping range cannot be changed on the circuit breaker side. Similar to today's typically available Type B, C (and D) circuit breakers (operable by laypersons, standardized tripping range for electrical planning).

[0022] The electrical planning is based on the non-changeable tripping range of the protective switching device.

[0023] This has the advantage that the triggering behavior can be selected within a triggering range (a triggering characteristic, for example, Type B or Type C), meaning the triggering range is used for a graduated triggering behavior. Graduated setting options can be configured within the standard limits of the standardized triggering range. This allows the normatively defined triggering range to be used, for example, to achieve a more robust or more sensitive triggering behavior.

[0024] This means that within the triggering range, the triggering behavior can be changed by a layperson in accordance with the standards.

[0025] This is advantageously made possible by a current sensor unit and, in particular, by an electronic interruption unit in conjunction with a corresponding control unit in the protective switching device. This allows the tripping behavior to be modified without deviating from the standard tripping behavior.

[0026] A standard refers in particular to a manufacturer-specific standard, an EN (European standard), or a DIN standard, i.e., a voluntary standard developed under the leadership of the German Institute for Standardization (DIN), in which tangible and intangible elements are standardized. DIN standards are developed at the suggestion and initiative of interested parties (usually German industry), whereby consensus is achieved among all parties involved. A manufacturer-specific standard can, for example, be a specification or definition of a triggering behavior according to a data sheet, manual, or catalog (from the manufacturer).

[0027] Advantageous embodiments of the invention are specified in the subclaims and in the exemplary embodiment.

[0028] In an advantageous embodiment of the invention, the mechanical isolating contact unit is assigned to the load-side connection, and the electronic interruption unit is assigned to the mains-side connection. In particular, the mechanical isolating contact unit can be operated by a mechanical handle to switch the opening or closing of at least one contact.

[0029] This has the particular advantage of providing a structure for a protective switching device in which the protective switching device can function even when the contacts of the mechanical isolating contact unit are open.

[0030] 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.

[0031] This has the particular advantage of providing a structure for a protective switching device which, on the one hand, provides power to the protective switching device and, on the other hand, enables a space-saving design by having only one switched pole.

[0032] 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 a load-side phase conductor connection are provided.

[0033] This has the particular advantage of providing a structure for a two-pole protective switching device, so that phase and neutral conductors can be connected directly and, for example, additional neutral conductor rails can be omitted.

[0034] In an advantageous embodiment of the invention, the at least one contact of the mechanical isolating contact unit can be opened by the control unit, but cannot be closed.

[0035] This has the particular advantage of ensuring a high level of safety for the protective switching device, as the contact cannot be closed incorrectly within the protective switching device.

[0036] In an advantageous embodiment of the invention, the at least one contact of the mechanical isolating contact unit has an isolating function. This can be an isolating function provided in accordance with the standards. In particular, such that the at least one contact can be opened by the control unit even if the mechanical handle is blocked, e.g., if the handle for the closed contact state is / is blocked. This has the particular advantage of providing a high level of safety and, in particular, a standards-compliant protective switching device for low-voltage circuits. The current flow can be galvanically interrupted at any time by opening the at least one contact.

[0037] In an advantageous embodiment of the invention, a third trigger curve (standard) can be selected within the trigger range. This allows a further triggering behavior to be selected within the trigger range.

[0038] This has the particular advantage that the tripping behavior can be further selected within a tripping range (a tripping characteristic, for example, Type B or Type C). This means that the tripping range is supplemented by a third tripping curve (with third specific current-time limit values), which can, for example, lie between the first and second tripping curves. This allows for a more graduated tripping behavior.

[0039] In an advantageous embodiment of the invention, at least one further triggering curve (or further triggering curves) can be selected within the triggering range in an analogous manner for the (one) triggering range. Thus, at least one further triggering behavior (or behaviors) can be selected within a triggering range.

[0040] This has the particular advantage that the triggering behavior can be selected more granularly within a triggering range, thus achieving a higher granularity.

[0041] In an advantageous embodiment of the invention, the standard for the standard-compliant protective switching device or for the standard-compliant line protection is the standard for line circuit breakers DIN EN 60898, in particular DIN EN 60898-1 or DIN EN 60898-2.

[0042] Alternatively, the standard for the standard-compliant protective switching device or for the standard-compliant line protection is a manufacturer-specific standard (for circuit breakers).

[0043] This has the particular advantage that standard-compliant triggering ranges (triggering characteristics) are available, for example type B, type C, which can be further staggered according to the invention, particularly for laypersons.

[0044] In an advantageous embodiment of the invention, the control unit comprises a microprocessor and a memory. The tripping curve (tripping characteristics) are stored in the control unit, particularly in its memory. This has the particular advantage that only a previously stored characteristic can be selected as the tripping curve, thus achieving a previously known and tested tripping behavior. All stored characteristic curves can be verified, for example, during certification (according to standard tests). This ensures that a specific tripping occurs according to the standard (even with different characteristic curves).

[0045] In an advantageous embodiment of the invention, the protective switching device is designed such that the current flow-preventing tripping occurs due to a high-resistance state of the switching elements of the electronic interruption unit, in particular when the at least one contact of the mechanical isolating contact unit remains closed.

[0046] This has the particular advantage of providing fast and flexible current flow avoidance and avoiding the switching times of mechanical current flow avoidance.

[0047] According to the invention, a corresponding method for a protective switching device for a low-voltage alternating current circuit, in particular with electronic (semiconductor-based) switching elements, with the same and further advantages is claimed.

[0048] The procedure for a protective switching device for standard-compliant line protection for low-voltage AC circuits is characterized by: - that if specific tripping current time limit values ​​forming a tripping curve are exceeded, a current flow-preventing tripping of the protective switching device is initiated, - that a standard for electrical installation material specifies current-time limit values ​​for tripping, so that a current flow in the low-voltage alternating current circuit must be avoided, and current-time limit values ​​for non-tripping, so that a current flow in the low-voltage alternating current circuit must be maintained, which identify a tripping range, - that the specific tripping current time limits are within the tripping range, - that at least one first tripping curve (Robust) and one second tripping curve (Sensitive) can be selected within the tripping range, so that different tripping behavior can be selected within a normatively marked tripping range (in or on the protective switching device).

[0049] It is advantageous to be able to select a third trigger curve (standard) within the trigger range.

[0050] The current flow-preventing tripping of the protective switching device is advantageously effected by a high-resistance state of switching elements of an electronic interruption unit, in particular when at least one contact of a mechanical isolating contact unit remains closed.

[0051] All embodiments, both in dependent form referring back to patent claim 1 or 13, and 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), increase the flexibility and expand the operability of a protective switching device by laypersons and provide a new concept for a protective switching device, in particular for line protection.

[0052] The described properties, features and advantages of this invention and the manner in which they are achieved will become clearer and more clearly understood in connection with the following description of the embodiments, which are explained in more detail in connection with the drawings.

[0053] The drawing shows: Fig. 1 a first representation of a protective switching device, Fig. 2 a first representation of a diagram, Fig. 3 a second representation of a diagram, Fig. 4 a third representation of a diagram.

[0054] Fig. 1 shows a representation of a novel protective switching device SG for line protection to protect an electrical low-voltage alternating current 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 grid side, A consumer (an energy sink) is usually connected to the load side; - a (two-pole) mechanical isolating contact unit MK with load-side connection points APLL, APNL and mains-side connection points APLG, APNG, A load-side connection point APNL is provided for the neutral conductor, a load-side connection point APLL for the phase conductor, a mains-side connection point APNG for the neutral conductor, and a mains-side connection point APLG for the phase conductor. The load-side connection points APNL and APLL are connected to the load-side neutral and phase conductor terminals NL and LL, so that the opening of contacts KKN and KKL to prevent current flow or the closing of the contacts to allow current flow in the low-voltage AC 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 case of a single-pole version is arranged in particular in the phase conductor L) with a grid-side connection point EUG, which is electrically connected to the grid-side phase conductor connection LG, and a load-side connection point EUL, which is electrically 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 current flow or a low-resistance state of the switching elements to allow current flow in the low-voltage AC circuit by means of semiconductor-based switching elements, - a current sensor unit SI, for determining the current level of the low-voltage alternating current circuit, which is arranged in particular in the phase conductor L, - a control unit SE connected to the current sensor unit SI, the mechanical isolating contact unit MK and the electronic interruption unit EU, where, if specific tripping current time limit values ​​forming a tripping curve are exceeded, avoidance of a current flow is initiated, - that a standard for electrical installation material specifies current-time limit values ​​for tripping, so that a current flow in the low-voltage alternating current circuit must be avoided, and current-time limit values ​​for non-tripping, so that a current flow in the low-voltage alternating current circuit must be maintained, which identify a tripping range, - that the specific tripping current time limits are within the tripping range, - that the protective switching device is designed according to the invention in such a way that at least one first trigger curve (Robust) and one second trigger curve (Sensitive) can be selected within the trigger range, so that a different triggering behavior can be selected within a normatively marked triggering range.

[0055] The protective switching device is advantageously designed such that the current-preventing triggering of both the first triggering curve and the second triggering curve occurs when the switching elements of the electronic interruption unit EU are in a high-impedance state. This is particularly true when at least one contact of the mechanical isolating contact unit MK remains closed.

[0056] Advantageously, a third trigger curve (standard) can be selected within the trigger range for the (one trigger range). This allows for a further trigger behavior to be selected within the trigger range. Similarly, at least one further trigger curve can be selected within the trigger range for the trigger range. Similarly, further trigger curves can be selected within the trigger range.

[0057] The standard for the standard-compliant protective switching device is preferably the standard for miniature circuit breakers DIN EN 60898, in particular DIN EN 60898-1 or DIN EN 60898-2. Alternatively, a manufacturer-specific standard is also possible.

[0058] The protective switching device SG can further be designed such that a temperature sensor TS connected to the control unit SE is provided in the protective switching device SG.

[0059] In particular, the temperature sensor TS is provided or arranged in the electronic interruption unit EU, as shown in Fig. 1 indicated.

[0060] 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 connections LG, NG, specifically between the mains-side neutral conductor connection NG and the mains-side phase conductor connection LG. Advantageously, the electronic interruption unit EU is switched to a low-impedance state when the magnitude of the instantaneous value of the voltage level falls below a first voltage limit, which is in particular less than or equal to 50 volts (or 25 volts or 10 volts).

[0061] In general, the mechanical isolating contact unit MK and the electronic interruption unit EU form a series circuit. The series circuit is connected to at least one mains-side connection and 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 Fig. 1. The mechanical isolating contact unit MK can be operated by a mechanical handle HH to switch the contacts open or close, as with a classic miniature circuit breaker (MCB).

[0062] The control unit can have a microprocessor and a memory. The tripping curves can then be stored in the control unit, particularly in the memory. The selected tripping curve can be taken from the memory. The values ​​of the selected tripping curve are compared with the determined fault current level in the control unit (e.g., using the microprocessor). If this value is exceeded, a current-preventing tripping is initiated.

[0063] In the example according to Fig. 1, the electronic interruption unit EU is designed as a single-pole device, 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 the mains-side neutral conductor connection NG of the housing GEH. In a single-pole version of the protective switching device SG, this connection can be omitted, as can the neutral conductor contact KKN of the mechanical isolating contact unit.

[0064] The 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.

[0065] The mechanical isolating contact unit MK can be operated using a mechanical handle HH on the protective switching device SG to manually open or close the KKL and KKN contacts. The mechanical handle HH indicates (when not blocked) the switching state (open or closed) of the contacts of the mechanical isolating contact unit MK on the protective switching device (specifically through a mechanical connection between the contacts and the handle).

[0066] 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 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 SE) is present. Without the enable or the enable signal, the handle HH can be operated, but the contacts cannot be closed ("permanent slipping").

[0067] The protective switching device SG has a power supply NT (not shown), for example, a power pack. In particular, the power supply NT is provided for the control unit SE. The power supply NT is connected, for example, to the mains-side neutral conductor connection NG and the mains-side phase conductor connection LG. A fuse, 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).

[0068] In the case of a purely single-pole protective switching device, the power supply is provided by an external power source / additional connections.

[0069] High-impedance refers to a state in which only a negligible current flows. In particular, high-impedance refers to resistance values ​​greater than 1 kiloohm, preferably greater than 10 kiloohms, 100 kiloohms, 1 megaohm, 10 megaohms, 100 megaohms, 1 gigaohm, or greater.

[0070] Low-resistance refers to a condition in which the current value specified on the protective device could flow. Specifically, low-resistance refers to resistance values ​​less than 10 ohms, preferably less than 1 ohm, 100 milliohms, 10 milliohms, 1 milliohm, or less.

[0071] In a first variant, the MK mechanical isolating contact unit can interrupt single-pole. This means that only one conductor (of the two / multiple 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.

[0072] In a second variant of the mechanical isolating contact unit MK, the neutral conductor also has mechanical contacts (two-pole interruption), as in Fig. 1 is shown.

[0073] The term "mechanical isolating contact unit MK" refers specifically 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 standard (minimum distance between contacts), - (mechanical) contact position indicator of the contacts of the mechanical isolating contact unit, - Release function or release functionality, i.e. an operation to interrupt the contacts of the mechanical isolating contact unit by the handle or control unit is always possible, so that no (permanent) blocking of the contacts in the closed state by the handle is possible.

[0074] In particular, release functionality means that at least one contact can be opened by the control unit, even if the mechanical handle is blocked (e.g. in the on state).

[0075] 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.

[0076] The minimum clearance between the contacts of the isolating contact unit is essentially voltage-dependent. Other parameters include the degree of contamination, the type of field (homogeneous, inhomogeneous), and the air pressure or altitude above sea level.

[0077] There are corresponding (additional) regulations or standards for these minimum clearances or creepage distances. These (additional) regulations specify, for example, the minimum clearance for an inhomogeneous and a homogeneous (ideal) electric field for air, depending on the degree of pollution. The surge voltage resistance is the resistance when a corresponding surge voltage is applied. Only if this minimum length (minimum distance) is present does the isolating contact unit or protective switching device exhibit an isolating function (isolating property).

[0078] In the sense of the invention, the DIN EN 60947 or IEC 60947 series of standards may be particularly relevant for the isolating function and its properties.

[0079] 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 impulse withstand voltage and the degree of pollution. The minimum clearance is, in particular, between 0.01 mm and 14 mm (at least). In particular, the minimum clearance is advantageously between 0.01 mm at 0.33 kV and 14 mm at 12 kV, especially for pollution degree 1 and especially for inhomogeneous fields.

[0080] In particular, a mechanical isolating contact unit does not mean a relay contact.

[0081] The protective switching device may have a (particularly wireless) communication unit COM, which is connected to the control unit SE or is a part of it.

[0082] Furthermore, a display unit AE can be provided. The display unit AE can be designed as a combined display and input unit. The display unit AE (display and input unit) is connected to the control unit SE or is 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. With a combined display and input unit, for example, the first or second (or third / further) tripping curve can be selected.

[0083] Alternatively or additionally, the first or second (or third / further) triggering curve can be selected, for example, via the communication unit COM.

[0084] The standard for standard-compliant line protection can advantageously be the standard for miniature circuit breakers DIN EN 60898 (VDE 0641-11) "Electrical installation equipment - Miniature circuit breakers for household and similar purposes." Part 1 covers "Miniature circuit breakers for alternating current (AC). German version: EN 60898-1."

[0085] From the above-mentioned standard, version from 2019, the following Table 7 (Section 8.6.1. - Standardized time-current characteristic range, pages 50 / 51 and 58 / 59) is shown.

[0086] The tripping characteristics of miniature circuit breakers (MCBs) must ensure adequate protection of the circuit without premature tripping.

[0087] The range of the time-current characteristic of a circuit breaker is defined by the specifications and the values ​​given in Table 7.

[0088] This table refers to a miniature circuit breaker (MCB) installed in accordance with the reference conditions and operating at the reference calibration temperature of 30 °C with a tolerance of +5 / 0 °C. Tests may be conducted at a suitable temperature; the results are referenced to 30 °C according to the manufacturer's specifications. In no case shall the deviation of the test current according to Table 7 exceed 1.2% per °C of the calibration temperature deviation.

[0089] If the circuit breakers are marked with a calibration temperature different from 30 °C, they are tested at this different temperature.

[0090] In the table is: - with "test" a designation of a test point by a lowercase letter, whereby this test point is assigned a respective current-time limit value, - "Type" (B, C, D) denotes the type of circuit breaker, where a type has a tripping range characterised by current-time limit values ​​for tripping (test points) so that a current flow in the low-voltage AC circuit must be avoided, and current-time limit values ​​for non-tripping (test points) so that a current flow in the low-voltage AC circuit must be maintained, - with “test current” the level of the test current related to the nominal current of the circuit breaker / protective switching device, ie the current limit value (the current-time limit value), - “Initial state” means the state of the circuit breaker / protective switching device at the beginning of the test, - with “limits of the tripping or non-tripping time” the time limit (of the current time limit) for tripping or non-tripping - with “Result to be achieved” a trigger (Trigger) or non-trigger (No trigger), - with comments other comments on the respective table item. Table 7 - Time-current tripping characteristics Test type Test current Initial state Limits of triggering or non-triggering time Result to be achieved Remarks a B, C, D 1.13 I n Called a t ≤ 1 h (for I n ≤ 63 A) t ≤ 2 h (for I n > 63 A) No triggering b B, C, D 1.45 I n Immediately after the exam a t < 1 h (for I n ≤ 63 A) t < 2h (for I n > 63 A) Trigger Continuous current increase within 5 s c B, C, D 2.55 I n Called a 1 s < t < 60s (for I n ≤ 32 A) 1 s < t < 120 s (for I n > 32 A) Trigger d BCD 3 I n 5 I n 10 I n Called a t ≤ 0.1 s No triggering Current is switched on by closing an auxiliary switch d BCD 3 I n 5 I n 10 I n Called a 0.1 s < t < 45 s (for I n ≤ 32 A) 0.1 s < t < 90 s (for I n > 32 A) 0.1 s < t < 15s (for I n ≤ 32 A) 0.1 s < t < 30 s (for I n > 32 A) 0.1 s < t < 4 s b (for I n ≤ 32 A) 0.1 s < t < 8 s (for I n > 32 A) Trigger Current is switched on by closing an auxiliary switch e BCD 5 I n 10 I n 20 I n Called a t < 0.1 s Trigger Current is switched on by closing an auxiliary switch a "Cold" means without prior stress. b For I n ≤ 10 A, t < 8 s is permissible.

[0091] The test points c and d are divided into c1, d1 for non-triggering and c2, d2 for triggering in more detail below, depending on their result.

[0092] Further points and explanations can be found in the standard.

[0093] Fig. Figure 2 shows a diagram illustrating a current-time response. On the horizontal X-axis, the ratio I / I N the magnitude of the current I to the nominal current I N (rated current) of the miniature circuit breaker / protective switching device. The current I is expressed as a multiple of the rated current I N (rated current). This ratio I / I N is shown logarithmically in the diagram.

[0094] The vertical Y-axis shows the trigger time t, with seconds / sec for the seconds range and minutes / min for the minutes range. The trigger time t is plotted logarithmically in the diagram.

[0095] In Fig. 2, the test points of the "Test" column according to Table 7 above from the standard, i.e. the current-time limit values ​​for tripping, so that a current flow in the low-voltage AC circuit must be avoided, and the current-time limit values ​​for non-tripping, so that a current flow in the low-voltage AC circuit must be maintained, are entered in the diagram. The current-time limit values ​​for tripping (b, c2, d2) are shown in Fig. 2 is indicated by a square standing on its tip (diamond shape). The current-time limit values ​​for non-tripping (a, c1, d1) are indicated by a circle in the figure. This is an example for a Type B circuit breaker / protective switching device.

[0096] This results in a triggering area marked by the test points, which is indicated by straight lines drawn accordingly.

[0097] In the left part of the diagram, from the origin of the diagram to the straight lines formed with the test points a, c1 and d1, is the area of ​​non-tripping ON, up to these current-time limit values ​​(a current is present for the defined time) a current flow in the low-voltage AC circuit must or should be (safely) guided by the miniature circuit breaker / protective switching device.

[0098] In the right part of the diagram, from the right or upper right edge to the straight lines formed with the test points b, c2, d2 and e, is the tripping area (area of ​​tripping) OFF, from these current time limit values ​​(a current is present for the defined time) a current flow in the low-voltage AC circuit must or should be (safely) prevented by a circuit breaker / protective switching device, the tripping must have occurred beforehand (but not in the non-tripping area).

[0099] The tripping zone AB lies between the non-tripping zone ON and the tripping zone (tripped zone OFF). Tripping typically occurs in this (transitional) zone between (safe) current conduction and (safe) current avoidance. This means that a current can still be conducted here, or a tripping event can occur here, although the precise current-time limit for tripping is not defined in detail.

[0100] It is important that in the non-tripping area a current is (safely) conducted (no tripping occurs) and in the tripping area (tripped area) the current is safely avoided (a tripping has previously occurred). This means that in the tripping area AB there are specific tripping current time limits at which a tripping is initiated by the protective switching device (prevention of current flow). These specific tripping current time limits form a tripping curve of the miniature circuit breaker / protective switching device. An example is shown in Fig. 2 such a trigger curve AK (standard) is shown.

[0101] Fig. 3 shows a diagram according to Fig. 2, with the difference that additional trigger curves are shown. First, a Robust trigger curve and a second Sensitive trigger curve. Both are located within the AB trigger range.

[0102] The first tripping curve, Robust, is located near the right-hand side of the OFF tripping range, allowing higher currents to be carried or currents to be carried for a longer time (or higher currents to be carried for a longer time). This means that tripping only occurs shortly before the (mandatory) OFF tripping range.

[0103] The second tripping curve, Sensitive, is close to the left-hand non-tripping ON range, so that even when the non-tripping ON range is left, small overcurrents or the brief presence of overcurrents lead to tripping (or small overcurrents over a short period of time lead to tripping). Thus, tripping occurs shortly after leaving the non-tripping ON range.

[0104] In Fig.3 also provides a third standard trigger curve within the trigger range AB, which is located approximately in the middle of the trigger range AB. This allows for the selection of a further trigger behavior within the trigger range.

[0105] Similarly, additional trigger curves can be provided within the trigger range. This allows at least one additional trigger behavior to be selected within the trigger range.

[0106] The tripping curves within the tripping range (example tripping range of type B) can be selected on or for the protective switching device by, in particular, a layperson.

[0107] The current-preventing tripping is advantageously achieved by a high-resistance state of the switching elements of the electronic interruption unit EU, particularly when at least one contact of the mechanical isolating contact unit MK remains closed.

[0108] Fig.4 shows a diagram according to Fig. 3 and Fig. 2 in a slightly different representation with information on the test points entered.

[0109] The tripping range of a miniature circuit breaker / protective switching device is used to carry out the (standardized or safe) electrical planning of a low-voltage circuit or a corresponding system.

[0110] According to the invention, at least two triggering characteristics are stored, for example in the control unit, so that the triggering behavior can be changed within certain limits (of the triggering range) by laypersons.

[0111] For example, circuit breakers have: - type A, which triggers between 2 and 3 times the rated current, - type B, which triggers between 3 and 5 times the rated current, - type C, which triggers between 5 and 10 times the rated current, - type D, which triggers between 10 and 20 times the rated current.

[0112] These tripping ranges, which originally originate from electromechanical line protection, are advantageously used according to the invention.

[0113] The invention and other aspects are described below in other words. Circuit breakers according to DIN EN 60898 with an adjustable current range are generally not permitted. Nevertheless, the standard specifies a tripping range, so that current devices with the same rated current and the same tripping range (the same tripping characteristic, e.g., type B, C, D) may still exhibit different tripping behavior.

[0114] The standard defines three ranges: a non-tripping range, in which the protective switching device must safely conduct current. A second tripping range (tripped state), in which the current must be safely interrupted. An intermediate range characterizes the so-called tripping range. The tripping of the protective switching device must occur within this intermediate range in order to comply with the standard according to the type. However, it is unclear how the tripping characteristic curve develops in this tripping / intermediate range.

[0115] Test points or current-time limit values: Test currents and test times defined by a standard, which together result in a test point or current-time limit value.

[0116] Current-time limit of non-tripping (small circle in Fig. 2 and Fig. 3): Test point at which the protective switching device must not trip when the test current is present until the test time.

[0117] Current-time limit value of tripping (square on its tip in Fig. 2 and Fig. 3): Test point at which the protective switching device must trip when the test current is present until the test time.

[0118] Current-time limits: (Continuous) limit of current-time values ​​defined by the test points.

[0119] (Lower) current-time limit of non-tripping: (Continuous) limit of current-time values ​​up to (or at) which the protective switching device must not trip.

[0120] (Upper) current-time limit of tripping (tripped): (Continuous) limit of current-time values ​​up to (or at) which the protective switching device must have tripped.

[0121] Ranges: Ranges of current-time values ​​defined by the current-time limits.

[0122] Range of tripping (tripped): Range resulting from the (standard) test points in which the current must be safely interrupted.

[0123] Non-trip area: Area resulting from the test points in which the current must be safely conducted.

[0124] Triggering range: Intermediate range between the non-triggering range and the triggering range (triggered).

[0125] By means of the electronic measuring technology (current sensor unit) and the digital algorithms (control unit) of a novel electronic protective switching device, various tripping characteristics can be realized according to the invention.

[0126] Fig. Figure 3 shows examples of what a possible implementation might look like. The three tripping characteristics or operating modes: "Standard," "Sensitive," and "Robust," could be offered and selected via a simplified setting option on the protective switching device.

[0127] The tripping behavior is defined by a corresponding digital algorithm (e.g., in the device firmware of the control unit). The invention now provides the possibility of subsequently modifying the tripping behavior of the protective switching device within existing standard limits.

[0128] The invention allows for a simple modification of the tripping behavior without changing the standardized tripping characteristic of the protective switching device (which was used for the electrical planning of the system).

[0129] This provides a setting option for an electronic circuit breaker / protective switching device that complies with existing standards.

[0130] Since the change in the triggering behavior is implemented in such a way that the standardized triggering range (the standardized triggering characteristic) is not changed, this change option can be made available in a simplified form even to laypeople.

[0131] 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. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited non-patent literature

[0000] DIN EN 60898

[0005] DIN EN 60947

[0006]

Claims

[1] Protective switching device for standard-compliant line protection for low-voltage alternating current circuits, 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), the series connection being 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 at least one contact to allow a current flow in the low-voltage alternating current 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 current flow or a low-resistance state of the switching elements to allow current flow in the low-voltage AC circuit, - a current sensor unit (SI) for determining the current level of the low-voltage alternating current 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 specific tripping current time limit values forming a tripping curve are exceeded, the avoidance of a current flow is initiated, - that a standard for electrical installation equipment specifies current-time limit values for tripping, so that a current flow in the low-voltage alternating current circuit must be avoided, and current-time limit values for non-tripping, so that a current flow in the low-voltage alternating current circuit must be maintained, which identify a tripping range, - that the specific tripping current time limits are within the tripping range, - that the protective switching device is designed in such a way that at least one first trigger curve (Robust) and one second trigger curve (Sensitive) can be selected within the trigger range, so that a different triggering behavior can be selected within a normatively designated triggering range. [2] Protective switching device (SG) according to claim 1, characterized bythat 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. [3] Protective switching device (SG) according to claim 1 or 2, characterized by 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 by 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 by that at least one contact of the mechanical isolating contact unit (MK) can be opened but not closed by the control unit (SE). [6] Protective switching device (SG) according to one of the preceding claims, characterized bythat the mechanical isolating contact unit (MK) can be operated by a mechanical handle (HH) in order to switch an opening of the at least one contact or a closing of the at least one contact. [7] Protective switching device (SG) according to claim 6, characterized by that the at least one contact of the mechanical isolating contact unit (MK) has an enabling functionality such that the at least one contact is opened by the control unit (SE), even if the mechanical handle (HH) is blocked. [8] Protective switching device (SG) according to one of the preceding claims, characterized by , that a third trigger curve (standard) can be selected within the trigger range, so that another triggering behavior can be selected within the triggering range. [9] Protective switching device (SG) according to one of the preceding claims, characterized by , that at least one further trigger curve can be selected within the trigger range, so that at least one further triggering behavior can be selected within the triggering range. [10] Protective switching device (SG) according to one of the preceding claims, characterized by that the standard is the standard for miniature circuit breakers DIN EN 60898, in particular DIN EN 60898-1 or DIN EN 60898-2, or is a manufacturer-specific standard. [11] Protective switching device (SG) according to one of the preceding claims, characterized by , that the control unit has a microprocessor and a memory, that the trigger curves are stored in the control unit. [12] Protective switching device (SG) according to one of the preceding claims, characterized by , that the protective switching device is designed in such a way that the current flow-preventing tripping occurs through a high-resistance state of the switching elements of the electronic interruption unit (EU), in particular when at least one contact of the mechanical isolating contact unit (MK) remains closed. [13] Procedure for a protective switching device for standard-compliant line protection for low-voltage alternating current circuits, - that if specific tripping current time limit values forming a tripping curve are exceeded, a current flow-preventing tripping of the protective switching device is initiated, - that a standard for electrical installation equipment specifies current-time limit values for tripping, so that a current flow in the low-voltage alternating current circuit must be avoided, and current-time limit values for non-tripping, so that a current flow in the low-voltage alternating current circuit must be maintained, which identify a tripping range, - that the specific tripping current time limits are within the tripping range, - that at least one first trigger curve (Robust) and one second trigger curve (Sensitive) can be selected within the trigger range, so that a different triggering behavior can be selected within a normatively designated trigger range. [14] Method according to claim 13, characterized by that a third trigger curve (standard) can be selected within the trigger range. [15] Method according to claim 13 or 14, characterized by that the current flow-preventing tripping of the protective switching device occurs due to a high-resistance state of switching elements of an electronic interruption unit (EU), in particular when at least one contact of a mechanical isolating contact unit (MK) remains closed.

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