Standard-compliant protective switching device and method

Abstract

This invention relates to a protective switchgear for a low-voltage AC circuit, comprising: - a mechanically disconnecting contact unit connected in series with an electronic interruption unit, wherein the series connection is connected on one side to at least one terminal on the grid side and on the other side to at least one terminal on the load side; - a current sensor unit for determining the magnitude of the current in the low-voltage AC circuit; - a control unit connected to the current sensor unit, the mechanically disconnecting contact unit, and the electronic interruption unit, wherein current flow avoidance is initiated when a specific trigger current-time limit value forming a trigger curve is exceeded; - a trigger current-time limit value for which current flow in the low-voltage AC circuit must be avoided and a non-trigger current-time limit value for which current flow in the low-voltage AC circuit must be carried out are pre-defined according to standards for electrical installation materials, the trigger current-time limit value and the non-trigger current-time limit value marking a trigger range; - a specific trigger current-time limit value located within the trigger range; - the protective switchgear is designed such that, for the trigger range, at least one first trigger curve and a second trigger curve can be selected within the trigger range, thereby enabling the selection of different trigger behaviors within the trigger range marked in a standard manner.

Description

[0001] Regardless of the grammatical gender of a particular term, people with either male or female gender identity are included. Technical Field

[0002] This invention relates to the field of standard-compliant (standard-bound) protective switchgear for line protection of low-voltage AC circuits, and to a method for using standard-compliant (standard-bound) protective switchgear for line protection of low-voltage AC circuits. Background Technology

[0003] Low voltage refers to voltages up to 1000 volts AC or up to 1500 volts DC. Specifically, low voltage refers to voltages greater than a small voltage of 50 volts AC or 120 volts DC.

[0004] Low-voltage circuits, low-voltage power grids, or low-voltage systems refer to circuits with rated or nominal currents up to 125 amps, more particularly up to 63 amps. Specifically, low-voltage circuits refer to circuits with rated or nominal currents up to 50 amps, 40 amps, 32 amps, 25 amps, 16 amps, or 10 amps. The current values ​​mentioned specifically refer to the rated current, nominal current, and / or breaking current, i.e., the maximum current that the circuit can normally carry, or the current at which the circuit would typically be interrupted, for example by a protective device, such as a protective switching device or a line protection switch or circuit breaker. Rated currents can be further graded, from 0.5 A through 1A, 2A, 3A, 4A, 5A, 6A, 7A, 8A, 9A, 10A, etc., up to 16A.

[0005] Circuit breakers are overcurrent protection devices known for a long time, used in electrical installations for low-voltage circuits. They protect circuits from damage caused by overheating due to excessive current and / or short circuits. Circuit breakers automatically shut off the circuit in case of overload and / or short circuit. They are non-automatically resettable fuses. For example, in standard DIN EN 60898 "ElektrischesInstallationsmaterial - Leitungsschutzschalter" Hausinstallationen und Zwecke (Electrical Installation Materials - Circuit Protective Switches for Home Installation and Similar Purposes) defines circuit protective switches and their characteristics.

[0006] Unlike line protection switches, circuit breakers are designed for currents greater than 125 A, and in some cases, for currents starting from 63 amps. Circuit breakers are constructed differently from line protection switches. For example, in standard DIN EN 60947… The term "(Low-voltage switchgear)" defines circuit breakers and their characteristics.

[0007] Unlike circuit breakers, line protection switches are constructed in a simpler and more refined manner. Line protection switches typically have the option of being mounted on so-called top-cap rails (support rails, DIN rails, TH35).

[0008] Circuit breakers are electromechanical in construction. Within their housing, they have mechanical switch contacts or operating current triggers for interrupting (triggering) current. Typically, bimetallic protection elements or bimetallic components are used for triggering (interrupting) in the event of prolonged overcurrent (overcurrent protection) or thermal overload (overload protection). Electromagnetic triggers with coils are used for short-term triggering when the overcurrent limit is exceeded or in the event of a short circuit (short circuit protection). One or more arc-extinguishing chambers or arc-extinguishing devices are provided. Furthermore, connecting elements for the conductors of the circuit to be protected are included.

[0009] Electromechanical line protection switches determine their triggering behavior through their constituent mechanical components, such as bimetallic circuits (overload protection) and electromagnetic triggers (e.g., trigger coils or magnetic triggers) (short-circuit protection). Triggering behavior refers to the current and duration under which the line protection switch automatically interrupts (= disconnects= breaks) the circuit. These electromechanical components define the triggering behavior of the protection device, determined during the manufacturing phase, through their structure. According to standards, line protection switches have triggering behavior (= triggering characteristics) within a triggering range defined by the standards. Particularly after the line protection switch is assembled, it is no longer possible or permissible to change or adjust the triggering behavior because electrical planning, according to standards, takes into account the triggering behavior (triggering characteristics) of the line protection switch in the dimensions of low-voltage circuits. Changing the triggering characteristics could result in the wiring cross-section (conductor cross-section) pre-given and laid by the electrical planning being insufficient, and the safety of the wiring (in low-voltage circuits) would therefore no longer correspond to the standard requirements.

[0010] Circuit breakers conforming to standard DIN EN 60898 have a specific triggering range (triggering characteristic). Generally, circuit breakers are distinguished by their triggering range, in addition to their rated current and structural form. Currently, standardized triggering range types (triggering characteristic types) are designated using uppercase letters. For example, there are standardized triggering characteristic types B, C, D, or manufacturer-specific triggering characteristics such as A, E, K, or Z. With these manufacturer-specific triggering characteristics, the manufacturer tests and guarantees triggering within the applicable range of the characteristic. Electrical planners can use this information to design (determine) the cross-sectional area of ​​low-voltage circuitry and the corresponding circuit protection provided by the appropriate circuit breakers.

[0011] Type B line protection switches are currently the most common type of line protection switch (in Germany). These line protection switches must be able to carry a rated current of, for example, 10 A or 16 A. Therefore, it is called "B10 line protection" or "B16 line protection" (or "B16 automatic switch (Automat)"). That is to say, for example, when the load current is 16A, the B16 line protection must always be able to carry that load current indefinitely over time.

[0012] The exemplary triggering range (triggering characteristics) mentioned above, used to practically cover the line protection switch in a standard-compliant manner, is due to electromechanical structural reasons. And the resulting tolerance limit This results in a response threshold. Therefore, to be precise, a line protection switch with a certain triggering range (triggering characteristics) always exhibits a slightly deviated triggering behavior (due to structural (tolerance) deviations caused by electromechanical factors). Logically, this applies not only to line protection switches from different manufacturers, but also to line protection switches from a single manufacturer or even a single production site. In this context, the line protection switch always (must) conform to the triggering characteristics / triggering range according to standards (or parameters given by the manufacturer).

[0013] Line protection switches always have a fixed triggering range (triggering characteristic). For example, a type B line protection switch only has the triggering range according to the type B standard. This triggering range cannot be changed. Therefore, by specifying the corresponding type with defined behavior in the planned electrical installation, reliable planability of the electrical installation can be achieved. Furthermore, the layperson's operability and usability of the protection switchgear are ensured.

[0014] Circuit breakers are also constructed electromechanically. They have mechanical switching contacts within the housing for interrupting (triggering) current. A current measuring device is typically present, connected to an electronic trigger unit (ETU). Alternatively, thermomagnetic trigger units (TMTUs) are also known in circuit breakers (particularly those with bimetallic and magnetic triggers). The (electronic) trigger unit ensures that the switching contacts open when the current-time limit is exceeded. The current-time limit is fixed within the electronic trigger unit. One or more arc-extinguishing chambers or devices for arc extinguishing are provided. Furthermore, connecting elements for the conductors of the circuit to be protected are provided.

[0015] According to standards, circuit breakers do not have triggering characteristics / triggering ranges. Triggering characteristics must be designed or calculated during the electrical planning process. Therefore, the correct setting of triggering characteristics must be performed by appropriately trained professionals during circuit breaker installation or commissioning. In this context, it is also referred to as "non-layman operability." That is, laypeople cannot operate or set the equipment. However, it must be possible to set triggering characteristic curves with specific current-time limits. Triggering characteristic curves can be set (in some cases, over a very wide range). This setting can only be performed by trained electrical personnel (instructed professionals). Layman operability (uninstructed personnel) and layman usability of circuit breakers are neither provided nor permitted (in cases of improper setting and incorrect triggering behavior, large currents in the circuit breaker can lead to serious property damage and personal injury). Summary of the Invention

[0016] The technical problem to be solved by this invention is to improve the type of line protection switch or protection switch device mentioned at the beginning, especially to achieve greater flexibility in triggering behavior.

[0017] The aforementioned technical problem is solved by a protective switchgear having the features of claim 1 and by the method according to claim 13.

[0018] According to the present invention, a protective switchgear for providing standard-compliant line protection for low-voltage AC circuits is provided, the protective switchgear having:

[0019] - A housing having at least one connector on the power grid side and at least one connector on the load side.

[0020] - A mechanically disconnecting contact unit connected in series with an (optional) electronic interruption unit, wherein the series connection is connected on one side to the at least one connection on the power grid side and on the other side to the at least one connection on the load side.

[0021] This mechanically disconnecting contact unit can be switched by opening at least one contact for preventing current flow or closing at least one contact for current flow in a low-voltage AC circuit.

[0022] - This (optional) electronic interruption unit can be switched via a semiconductor-based switching element to a high-ohmic state for preventing current flow or a low-ohmic state for current flow in low-voltage AC circuits.

[0023] - A current sensor unit used to determine the magnitude of the current in a low-voltage AC circuit.

[0024] - A control unit, which is connected to a current sensor unit, a mechanical disconnect contact unit, and (optionally) an electronic interrupt unit.

[0025] Specifically, when the specific trigger current-time limit value for forming the trigger curve is exceeded, current flow prevention (in the low-voltage AC circuit) is initiated, particularly through an (optional) electronic interruption unit.

[0026] - Standards for electrical installation materials, especially for line protection switches, predefine the trigger range marked by current-time limits (current-time limits refer to the time-current limits according to the standard, which are usually test points associated with the standard). That is, the trigger range is marked (or defined) by a single test point (current-time limit).

[0027] - A triggering range is marked by an upper (upper) current-time limit that must be avoided to trigger current flow in a low-voltage AC circuit and a lower (lower) current-time limit that must be allowed to carry current flow in a low-voltage AC circuit without triggering.

[0028] - The specific trigger current-time limit is within the trigger range (that is, for example, the specific trigger current-time limit is (only) between the current-time limit for triggering and the current-time limit for not triggering).

[0029] (This prevents current flow in the low-voltage circuit from being initiated when the specific trigger current-time limit value that forms the trigger curve is exceeded (and when it is below that, triggering is not initiated).)

[0030] - This protective switchgear is designed to be,

[0031] This allows for the selection of at least one first trigger curve and one second trigger curve within a given trigger range.

[0032] This allows for the selection of different trigger behaviors within a trigger range that is marked in a standard manner.

[0033] In other words, the protective switchgear has two trigger curves, such that within the trigger range, either a first trigger curve (with a (first) specific current-time limit value) or a second trigger curve (with a (second) specific current-time limit value) is used to trigger, i.e., to prevent current flow (in the low-voltage AC circuit to be protected by the protective switchgear).

[0034] The first trigger curve may, for example, have first specific current-time limits, which are close to or almost identical to the current-time limit at which triggering occurs. Therefore, within the trigger range, the protective switching device triggers only when it is close to or shortly before triggering as required by the standard. This achieves high power supply safety because a brief period exceeding the trigger range does not necessarily lead to a trigger that prevents current flow.

[0035] The second trigger curve may, for example, have second specific current-time limits that are close to or almost identical to the non-triggered current-time limit. Therefore, within the trigger range, the protective switching device triggers only after the current flow has almost left or has left the (safe) load that is required by standard procedures. This achieves high safety because within the trigger range, especially briefly or slightly exceeding it, will not trigger a current-avoidance mechanism.

[0036] The trigger range cannot be changed on the protective switchgear side. This is similar to the currently available type B, C (and D) line protection switches (lazy operator, with standardized trigger ranges for electrical planning).

[0037] Electrical planning is based on the unchangeable trigger range of protective switching equipment.

[0038] This has the advantage that triggering behavior can be selected within a trigger range (e.g., triggering features of type B or type C), meaning that tiered triggering behavior can be achieved using trigger ranges. Within the standard limits of a standardized trigger range, tiered settings are possible. Therefore, trigger ranges defined in a standard manner can be used to achieve, for example, more robust or more sensitive triggering behavior.

[0039] Therefore, laypeople can advantageously modify the triggering behavior in a standard-compliant manner within the triggering scope.

[0040] This advantageously enables this to be achieved in protective switching devices, particularly through current sensor units, and especially through electronic interruption units, in conjunction with corresponding control units. Therefore, the triggering behavior can be changed without deviating from standard triggering behavior.

[0041] In particular, "standard" refers to a manufacturer-specific standard, or an EN (standard). Norm (European Standard) or DIN (German Standards Institute) standards, i.e., the standards of the German Institute for Standardization (Deutschen Instituts) DIN standards are voluntary standards developed under the guidance of the DIN Normung (German Standard for Standards), which provide unified specifications for both tangible and intangible objects. DIN standards are formed at the suggestion and initiative of relevant stakeholders (usually German companies), with all parties reaching a consensus.

[0042] Manufacturer-specific standards may be, for example, descriptions or definitions of triggering behaviors based on (the manufacturer's) data sheets, manuals, or product catalogs.

[0043] Advantageous designs of the invention are given in the dependent claims and embodiments.

[0044] In an advantageous embodiment of the invention, the mechanical disconnect contact unit is associated with a connector on the load side, and the electronic interrupt unit is associated with a connector on the power grid side. In particular, the mechanical disconnect contact unit can be operated by a mechanical handle to switch at least one contact open or at least one contact closed.

[0045] This has the particular advantage of providing a structure for protecting switchgear, in which the functional capability of the protective switchgear is maintained even when the contacts of the mechanically disconnecting contact unit are open.

[0046] In an advantageous embodiment of the invention, two grid-side connectors and at least one load-side connector are provided. Specifically, a grid-side phase conductor connector, a grid-side neutral conductor connector, and a load-side phase conductor connector are provided.

[0047] This has the following particular advantages: it provides a structure for protecting switching equipment, which, on the one hand, provides the energy supply for protecting the switching equipment, and on the other hand, enables a space-saving construction by switching only one pole.

[0048] In an advantageous embodiment of the invention, two grid-side connectors and two load-side connectors are provided. Specifically, a grid-side neutral conductor connector, a grid-side phase conductor connector, a load-side neutral conductor connector, and a load-side phase conductor connector are provided.

[0049] This has the particular advantage of providing a structure for a two-pole protective switchgear, which allows the phase conductors and neutral conductors to be directly connected, and, for example, eliminates the need for an additional neutral conductor busbar.

[0050] In an advantageous embodiment of the invention, at least one contact of the mechanically separating contact unit can be disconnected by the control unit, but cannot be closed by the control unit.

[0051] This has the particular advantage of providing high safety for the protective switchgear because the contacts will not be mistakenly closed inside the protective switchgear.

[0052] In an advantageous embodiment of the invention, at least one contact of the mechanically disconnecting contact unit has a free-switching function. This free-switching function can be configured according to standard conditions. Specifically, it enables at least one contact to be disconnected by the control unit even when the mechanical handle is locked, i.e., when the handle is locked / locked for a closed contact state.

[0053] This offers the particular advantage of providing high safety and standard-compliant protective switching equipment for low-voltage circuits. Current flow can be interrupted at any time by disconnecting at least one contact.

[0054] In an advantageous embodiment of the invention, for a given trigger range, a third trigger curve (standard) can be selected within that trigger range. Therefore, additional triggering behavior can be selected within that trigger range.

[0055] This has the particular advantage that the triggering behavior can be further selected within a triggering range (e.g., triggering characteristics of type B or type C). In other words, the triggering range is supplemented by a third triggering curve (having a third specific current-time limit value) that can be located between the first and second triggering curves. Therefore, further graded triggering behavior can be achieved.

[0056] In an advantageous embodiment of the invention, similarly, for one trigger range, at least one other trigger curve (or additional trigger curve) can be selected within that trigger range. Therefore, at least one other (or additional) triggering behavior can be selected within that trigger range.

[0057] This has the following particular advantage: it allows for further granular selection of triggering behavior within the trigger range, achieving a higher level of granularity.

[0058] In an advantageous embodiment of the invention, the standard for compliant protective switchgear or for compliant line protection is the standard for line protection switches DIN EN 60898, particularly DIN EN 60898-1 or DIN EN 60898-2.

[0059] Alternatively, the standard for compliant protective switchgear or for compliant line protection is a manufacturer-specific standard (for line protection switches).

[0060] This has the particular advantage that there are standard trigger ranges (trigger characteristics) here, such as type B and type C, and according to the invention, these trigger ranges can be further classified in a layman's operable manner.

[0061] In an advantageous embodiment of the invention, the control unit has a microprocessor and a memory. The trigger curve (trigger characteristic curve) is stored in the control unit, and particularly in its memory.

[0062] This has the particular advantage that it allows the selection of only previously stored feature curves as trigger curves, thus enabling previously known and verified triggering behavior. For example, all stored feature curves can be verified together (according to standard testing). This ensures that specific triggering occurs according to standards (even when feature curves differ).

[0063] In an advantageous embodiment of the invention, the protective switching device is designed such that the prevention of current flow is triggered by a high-ohmic state of the switching element of the electronic interruption unit, particularly when at least one contact of the mechanically disconnecting contact unit remains closed.

[0064] This has the particular advantage of providing fast and flexible current flow avoidance, and avoiding the switching time of mechanical current flow avoidance.

[0065] According to the present invention, protection is sought for a corresponding method of protective switching device for low-voltage AC circuits having the same and other advantages, the protective switching device having, in particular, electronic (semiconductor-based) switching elements.

[0066] The protective switchgear is used to provide standard-compliant line protection for low-voltage AC circuits, and the method using the protective switchgear is characterized by:

[0067] - When the specific trigger current-time limit value that forms the trigger curve is exceeded, the protective switching device is activated to prevent current flow.

[0068] - Standards for electrical installation materials predefine triggering current-time limits that must be avoided when current flows in low-voltage AC circuits and non-triggering current-time limits that must be allowed to carry current flows in low-voltage AC circuits. These triggering and non-triggering current-time limits mark the triggering range.

[0069] - The specific trigger current-time limit values ​​are within the trigger range.

[0070] - For the trigger range, it is possible to select at least one first trigger curve (robust) and one second trigger curve (sensitive) within the trigger range.

[0071] This allows for the selection of different triggering behaviors (within or on the protective switchgear) within a triggering range marked in a standard manner.

[0072] Advantageously, for this trigger range, a third trigger curve (standard) can be selected within this trigger range.

[0073] Advantageously, the protection of the switching equipment from current flow is triggered by the high-ohmic state of the switching element of the electronic interruption unit, particularly when at least one contact of the mechanical disconnecting contact unit remains closed.

[0074] All design solutions, not only by referencing the dependent form of claim 1 or 13, but also by referring only to the individual features or combinations of features of the claims, especially the reference of the device dependent claims to the independent method claims (and vice versa), have achieved improved flexibility and expanded operability for protecting switchgear, and have provided a new design solution for protecting switchgear, especially for line protection. Attached Figure Description

[0075] The features, characteristics, and advantages of the present invention, as well as its implementation, will become clearer and easier to understand in conjunction with the following description of the embodiments, which are described in detail with reference to the accompanying drawings.

[0076] Here, in the attached diagram:

[0077] Figure 1 The first illustration shows the protection switchgear.

[0078] Figure 2 The first illustration of the curve is shown.

[0079] Figure 3 The second illustration of the curve is shown.

[0080] Figure 4 The third illustration of the graph is shown. Detailed Implementation

[0081] Figure 1 A diagram is shown of a novel protective switchgear SG with a housing GEH for line protection. This line protection is used to protect low-voltage AC circuits. The protective switchgear SG has:

[0082] - The neutral conductor terminal NG on the grid side, the phase conductor terminal LG on the grid side, the neutral conductor terminal NL on the load side, and the phase conductor terminal LL on the load side of the low-voltage circuit.

[0083] On the grid side, an energy source is typically connected.

[0084] On the load side, electrical equipment (energy sink) is usually connected.

[0085] - A (two-pole) mechanically disconnecting contact unit MK, which has load-side connection points APLL and APNL and grid-side connection points APLG and APNG.

[0086] Specifically, a load-side connection point APNL is provided for the neutral conductor; a load-side connection point APLL is provided for the phase conductors; a grid-side connection point APNG is provided for the neutral conductor; and a grid-side connection point APLG is provided for the phase conductors. The load-side connection points APNL and APLL are connected to the load-side neutral conductor terminals and phase conductor terminals NL and LL, respectively, thereby allowing switching between the opening of contacts KKN and KKL (used to prevent current flow) and the closing of contacts (used to allow current flow in low-voltage AC circuits).

[0087] The mechanically separating contact unit can also be implemented as a single-pole mechanically separating contact unit, i.e., having one contact, wherein the contact KKL is preferably arranged in the phase conductor L, thus eliminating the need for a neutral conductor N that penetrates the protective switchgear SG.

[0088] - Electronic interruption unit EU, especially unipolar electronic interruption unit EU (which is particularly arranged in phase conductor L in unipolar implementation).

[0089] It has a grid-side connection point EUG, which is electrically connected to the grid-side phase conductor connector LG, and

[0090] The load-side connection point EUL is electrically connected to the grid-side connection point APLG of the mechanical disconnect contact unit MK.

[0091] The electronic interruption unit utilizes semiconductor-based switching elements, which can have a high-ohmic state for preventing current flow or a low-ohmic state for current flow in low-voltage AC circuits.

[0092] - A current sensor unit SI is used to determine the magnitude of the current in a low-voltage AC circuit. This current sensor unit SI is specifically arranged in the phase conductor L.

[0093] - Control unit SE, which is connected to current sensor unit SI, mechanical disconnect contact unit MK, and electronic interrupt unit EU.

[0094] Specifically, when the specific trigger current-time limit value for forming the trigger curve is exceeded, the flow of the initiation current is avoided.

[0095] - Standards for electrical installation materials predefine triggering and non-triggering current-time limits. The triggering current-time limits necessitate preventing current flow in low-voltage AC circuits, while the non-triggering current-time limits ensure the carrying capacity of current flow in low-voltage AC circuits. These triggering and non-triggering current-time limits mark the triggering range.

[0096] - The specific trigger current-time limit value falls within this trigger range.

[0097] According to the present invention, the protective switchgear is designed to,

[0098] For this trigger range, at least one first trigger curve (robust) and one second trigger curve (sensitive) can be selected within this trigger range.

[0099] This allows for the selection of different trigger behaviors within a trigger range that is marked in a standard manner.

[0100] This protective switching device is advantageously designed so that the avoidance of current flow triggering, not only for the first trigger curve but also for the second trigger curve, is achieved through the high-ohmic state of the switching element of the electronic interrupt unit EU. This is particularly true when at least one contact of the mechanically disconnecting contact unit MK remains closed.

[0101] Advantageously, for this trigger range, a third trigger curve (standard) can be selected within that trigger range. This allows for the selection of another trigger behavior within the trigger range. Similarly, for this trigger range, at least one other trigger curve can be selected within that trigger range. In a similar manner, another trigger curve can be selected. This allows for the selection of at least one other trigger behavior within the trigger range.

[0102] The most advantageous standard for this compliant protective switchgear is DIN EN 60898, specifically DIN EN 60898-1 or DIN EN 60898-2, for line protection switches.

[0103] The replacement is a manufacturer-specific standard.

[0104] Furthermore, the protective switchgear SG can be designed to include a temperature sensor TS connected to the control unit SE.

[0105] In particular, such as Figure 1 As indicated, the temperature sensor TS is set or arranged at the electronic interrupt unit EU.

[0106] Furthermore, a first voltage sensor unit SUA connected to the control unit SE can be provided. This first voltage sensor unit SUA determines the magnitude, and in particular the instantaneous value, of the voltage at the terminals LG and NG on the low-voltage circuit, particularly on the grid side, and especially between the neutral conductor terminal NG on the grid side and the phase conductor terminal LG on the grid side. Advantageously, when the instantaneous value of the voltage is below, in particular less than or equal to, a first voltage limit of 50 volts (or 25 volts or 10 volts), the electronic interrupt unit EU is switched to a low-ohm state.

[0107] Generally, the mechanical disconnect contact unit MK and the electronic interrupt unit EU form a series circuit. This series circuit is connected to at least one terminal on the power grid side and at least one terminal on the load side. For example, in Figure 1 As shown, the mechanical disconnect contact unit MK can be advantageously associated with a connector on the load side, while the electronic interrupt unit EU can be advantageously associated with a connector on the grid side.

[0108] The mechanically disconnecting contact unit MK can be operated via a mechanical handle HH to switch the contacts open or closed, just like in a classic line protection switch or miniatur circuit breaker (MCB).

[0109] The control unit may have a microprocessor and memory. The trigger curve can then be stored in the control unit, particularly in the memory. The selected trigger curve can be retrieved from the memory. In the control unit (e.g., using a microprocessor), the value of the selected trigger curve is compared with the determined magnitude of the fault current. If the magnitude is exceeded, a current-prevention trigger is activated.

[0110] According to Figure 1In the example, the electronic interruption unit EU is implemented as unipolar, and in this example, it is implemented in the phase conductor. Here, the connection point APNG on the grid side of the neutral conductor of the mechanical disconnect contact unit MK is connected to the neutral conductor connector NG on the grid side of the housing GEH. In the unipolar variant of the protective switchgear SG, this connection can be omitted, and the neutral conductor contact KKN of the mechanical disconnect contact unit can also be omitted.

[0111] The protective switchgear SG is advantageously designed such that the contacts of the mechanically disconnecting contact unit MK can be opened by the control unit SE, but cannot be closed by the control unit SE, as indicated by the arrow from the control unit SE to the mechanically disconnecting contact unit MK.

[0112] The mechanically disconnecting contact unit MK can be operated via the mechanical handle HH on the protective switchgear SG to switch the manual (human-made) opening or closing of contacts KKL and KKN. The mechanical handle HH (in the unlocked state) (especially through the mechanical connection between the contacts and the handle) indicates the on / off state (open or closed) of the contacts of the mechanically disconnecting contact unit MK on the protective switchgear.

[0113] The mechanically disconnecting contact unit MK is advantageously designed so that the contacts can only be closed (manually) via a mechanical handle after a release (Enable) signal, particularly a release signal. That is, the contacts KKL and KKN of the mechanically disconnecting contact unit MK can only close via the handle HH in the presence of a release or a release signal (from the control unit SE). Without a release or release signal, the handle HH can be operated, but the contacts will not close ("Dauerrutscher, continuous sliding").

[0114] The protective switchgear SG has an energy supply device NT (not shown), such as a power supply unit. In particular, the energy supply device NT is configured for use with the control unit SE. The energy supply device NT is connected, for example, to the neutral conductor terminal NG and the phase conductor terminal LG on the grid side. In the connection with the neutral conductor terminal NG (or / and the phase conductor terminal LG) on the grid side, a safety device SS, particularly a fuse or / and a switch, can be advantageously provided.

[0115] In the case of purely single-pole protection switchgear, energy supply is provided through an external energy source / other connection.

[0116] High ohms refers to a state in which only a negligible current flows. In particular, high ohms refers to a resistance value greater than 1 kiloohm, preferably greater than 10 kiloohms, 100 kiloohms, 1 megaohm, 10 megaohms, 100 megaohms, 1 gigaohms or greater.

[0117] Low ohms refers to a state in which a given current value can flow through a protective switching device. In particular, low ohms refers to a resistance value of less than 10 ohms, preferably less than 1 ohm, 100 milliohms, 10 milliohms, 1 milliohm, or less.

[0118] In the first variant, the mechanically disconnecting contact unit MK can be interrupted in a unipolar manner. That is, only one conductor (among two or more conductors), particularly the active conductor or phase conductor, is interrupted, i.e., it has one mechanical contact. Thus, the neutral conductor has no contact, i.e., the neutral conductor is directly connected.

[0119] As in Figure 1 As illustrated in the second variant of the mechanically separated contact unit MK, the neutral conductor also has mechanical contacts (two-pole interruption).

[0120] In particular, the mechanically separating contact unit MK refers to the (standard-compliant) separation function achieved through the separating contact unit MK. The separation function includes the following:

[0121] - According to the standard minimum air gap (minimum distance between contacts).

[0122] - Mechanical contact position indication of the contacts in a mechanically disconnecting contact unit.

[0123] - Free trigger or free switch function, that is, it can always be operated by the handle or control unit to interrupt the contacts of the mechanically disconnecting contact unit, so that the contacts cannot be (continuously) locked in the closed state by the handle.

[0124] In particular, the free-trigger or free-switch function means that at least one contact can be disconnected by the control unit even if the mechanical handle (e.g., in the ON state) is locked.

[0125] In addition, the standard separation function can have the ability to disconnect the contact unit or handle in both the on and off states.

[0126] Regarding the minimum air gap between the contacts of the separation contact unit, it is essentially voltage-related. Other parameters include the degree of contamination, field type (uniform, non-uniform), and air pressure or altitude.

[0127] For these minimum air gaps or creepage paths, there are corresponding (alternative) regulations or standards. These (alternative) regulations, for example, specify minimum air gaps based on the degree of contamination, for non-uniform and uniform (ideal) electric fields, when air is used for impulse withstand voltage. Impulse withstand voltage is the ability to withstand a corresponding impulse voltage. Only when this minimum length (minimum gap) exists does the disconnecting contact unit or protective switching device have a disconnecting function (disconnector characteristic).

[0128] Here, in the sense of the present invention, the function and characteristics of the separator are particularly relevant to the DIN EN 60947 or IEC 60947 series of standards.

[0129] The disconnecting contact unit is advantageously characterized, based on the nominal impulse withstand voltage and the degree of contamination, by the minimum air gap of the disconnected contact in the open position (open circuit position, contact disconnected). This minimum air gap is particularly between 0.01 mm and 14 mm. Especially for contamination level 1 and especially for non-uniform electric fields, the minimum air gap is advantageously between 0.01 mm at 0.33 kV and 14 mm at 12 kV.

[0130] In particular, mechanically disconnected contact units do not refer to relay contacts.

[0131] Protective switchgear may have (especially wireless / wireless) communication unit COM, which is connected to or is part of the control unit SE.

[0132] In addition, 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 or is part of the control unit SE. The display unit has a display device visible on the protective switching equipment, particularly for displaying the high-ohm or low-ohm state of the electronic interrupt unit EU. Using the combined display and input unit, for example, a first or second (or third / additional) trigger curve can be selected.

[0133] Alternatively or additionally, for example, the first or second (or third / other) trigger curve can be selected via the communication unit COM.

[0134] The standard for compliant line protection can advantageously be the standard for line protection switches DIN EN60898 (VDE 0641-11) "Elektrisches Installationsmaterial -Leitungsschutzschalter" Hausinstallationen und Zwecke (Electrical Installation Materials - Circuit Protection Switches for Home Installation and Similar Purposes). Part 1 includes "Leitungsschutzschalter". Wechselstrom (AC) (Line protection switch for AC). German version: EN 60898-1.

[0135] The following Table 7 is copied from the 2019 version of the aforementioned standard (Section 8.6.1. – Standardized Time-Current Characteristic Range, pp. 50 / 51 and 58 / 59).

[0136] The triggering characteristics of a line protection switch (LS switch) must ensure that the circuit is properly protected without triggering prematurely.

[0137] The range of the time-current characteristic curve of the LS switch is defined by the specifications and the values ​​given in Table 7.

[0138] This table pertains to the following line protection switch (LS switch), which is installed in accordance with reference conditions and operates with a limit deviation of +5 / 0°C at a reference calibration temperature of 30°C. Tests can be performed at appropriate temperatures, according to the manufacturer's given parameters, with results referenced to 30°C. Under no circumstances should the deviation of the test current according to Table 7 exceed 1.2% per 1K of the calibration temperature deviation.

[0139] When the marked line protection switch has a calibration temperature that deviates by 30°C, the line protection switch is tested at that temperature.

[0140] In this table:

[0141] - "Test" refers to a test point indicated by a lowercase letter, which is associated with a corresponding current-time limit.

[0142] - "Type" (B, C, D) refers to the type of line protection switch. One type has the following trigger range, which is marked by the current-time limit value for triggering (test point) when current flow in the low-voltage AC circuit must be avoided, and the current-time limit value for not triggering (test point) when current flow in the low-voltage AC circuit must be carried.

[0143] - "Test current" refers to the magnitude of the test current relative to the rated current of the line protection switch / protection switchgear, i.e., the current limit value (current-time limit value).

[0144] - "Initial state" refers to the state of the line protection switch / protection switchgear at the start of the test.

[0145] - "The limit of trigger time or non-trigger time" refers to the time limit value (current-time limit value) for triggering or not triggering.

[0146] - "The desired result" refers to whether to trigger (trigger) or not trigger (not trigger).

[0147] - Notes refer to other notes regarding the relevant table items.

[0148] Table 7 - Time-current triggering characteristics

[0149]

[0150] Test points c and d correspond to results that are further subdivided into c1 and d1, representing no triggering, and c2 and d2, representing triggering.

[0151] Other key points and explanations can be found in the standard.

[0152] Figure 2 A graph illustrating the current-time behavior is shown. The magnitude of the current I of the line protection switch / protective switching device relative to its rated current is plotted on the horizontal X-axis. (Nominal current) ratio As the rated current The ratio of (nominal current) to the magnitude of current I is plotted. This ratio is shown logarithmically in the graph. The trigger time t is plotted on the vertical Y-axis, where the given parameter seconds / sek represents the range of seconds, and the given parameter minutes / min represents the range of minutes. The trigger time t is plotted logarithmically in this graph.

[0153] exist Figure 2 In this graph, the test points according to the "Test" column of Table 7 above are plotted, namely, the current-time limit for triggering the circuit that must be avoided from current flow in the low-voltage AC circuit, and the current-time limit for not triggering the circuit that must be able to withstand current flow in the low-voltage AC circuit. Figure 2 In the diagram, the current-time limits for triggering (b, c2, d2) are marked by squares (diamonds) erected on the peaks. In this diagram, the current-time limits for non-triggering (a, c1, d1) are marked by circles. This example is for a type B line protection switch / protective switchgear.

[0154] This yields the trigger range marked by the test point, which is exemplarily marked by a correspondingly drawn straight line.

[0155] On the left side of the graph, the "on" range where no triggering occurs is located from the origin of the graph up to the straight line formed by test points a, c1, and d1, until these current-time limits (where current exists within a defined time) must or must carry the current flow in the low-voltage AC circuit through the line protection switch / protection switchgear (safely).

[0156] On the right side of the graph, the "disconnected" range (the triggered range) is located on the straight line formed by test points b, c2, d2, and e, starting from the right or upper right edge. From these current-time limits (where current exists within a defined time), the current flow in the low-voltage AC circuit must be prevented (but not within the range where triggering is not required) by the line protection switch / protection switchgear.

[0157] The triggering range AB lies between the "on" state of the non-triggered range and the "off" state of the triggered range (the already triggered range). Triggering typically occurs within the (transition) range between (safe) current carrying and (safe) current avoidance. That is, current can still be carried here, or triggering can occur here, where the precise current-time limits for triggering are not defined in detail.

[0158] Importantly, current is carried safely within the non-triggered range (without triggering), while current is safely avoided within the triggered range (the already triggered range) (pre-triggered). That is, specific trigger current-time limits lie within the trigger range AB, and triggering is performed by the protective switching equipment at these specific trigger current-time limits (avoidance of initiating current flow). These specific trigger current-time limits form the trigger curve of the line protection switch / protective switching equipment. Figure 2 The trigger curve AK (“Standard”) is illustrated in the example.

[0159] Figure 3 It shows according to Figure 2 The graph shows two different trigger curves, one for "robust" and the other for "sensitive." Both are plotted within the trigger range AB.

[0160] The first trigger curve is "robust" and the trigger range near the right is "disconnected," allowing it to carry a larger current or a longer current for a longer period of time (or a larger current for a longer period of time). Therefore, triggering occurs shortly before the (forced) trigger range is "disconnected."

[0161] The second trigger curve is "sensitive" and close to the non-triggered range on the left. Therefore, when the device "turns on" after leaving this non-triggered range, a small overcurrent or a short-term overcurrent has already triggered the trigger (or a small overcurrent within a short period triggers the trigger). Thus, triggering occurs shortly after leaving this non-triggered range.

[0162] In addition, Figure 3 Within the trigger range AB, a third trigger curve "standard" is set, which is roughly positioned in the middle of the trigger range AB. Therefore, other trigger behaviors can be selected within the trigger range.

[0163] Similarly, additional trigger curves can be set within the trigger range. Therefore, at least one additional trigger behavior can be selected within the trigger range.

[0164] In particular, it is possible for laypeople to select trigger curves within the trigger range (e.g., the trigger range of type B) on the protection switchgear or for the protection switchgear.

[0165] Triggering of current flow can be advantageously prevented by using the high-ohmic state of the switching element of the electronic interrupt unit EU. This is particularly true when at least one contact of the mechanical disconnect contact unit MK remains closed.

[0166] Figure 4 The diagram is shown in a slightly different way according to Figure 3 and Figure 2 The graph shows information about the test points.

[0167] The trigger range of line protection switches / protection switchgear is used to perform (standardized or safe) electrical planning for low-voltage circuits or corresponding equipment.

[0168] According to the present invention, for example, at least two trigger characteristic curves are stored in the control unit, so that the triggering behavior can be changed within certain limits (of the triggering range) in a layman's operable manner.

[0169] In the case of a line protection switch, for example:

[0170] - Type A, which, for example, triggers at 2 to 3 times the rated current.

[0171] - Type B, which, for example, triggers between 3 and 5 times the rated current.

[0172] - Type C, which, for example, triggers between 5 and 10 times the rated current.

[0173] - Type D, which, for example, is triggered between 10 and 20 times the rated current.

[0174] According to the invention, these trigger ranges, originally derived from electromechanical circuit protection, are advantageously utilized.

[0175] The invention and other aspects will now be described using other terminology. Line switches with configurable current ranges according to DIN EN 60898 are generally not permitted. Nevertheless, standards for trigger ranges are still provided, allowing contemporary devices with the same rated current and the same trigger range (the same triggering characteristics, e.g., types B, C, D) to still exhibit different triggering behaviors.

[0176] This standard yields three ranges. The first is the non-triggered range, where the protective switchgear must safely carry current. The second is the triggered (triggered) range, where the current must safely be interrupted. The third is the so-called triggering range. The protective switchgear must trigger within this intermediate range to comply with the standard according to this type. However, how the triggering characteristic curve operates within this triggering / intermediate range is open.

[0177] Test point or current-time limit: The test point or current-time limit is generated by the test current and test time defined by the standard.

[0178] Current-time limit without triggering ( Figure 2 and Figure 3 The small circle in the middle): a test point where the protective switchgear is not allowed to be triggered when it carries the test current before the test time is reached.

[0179] Triggering current-time limit ( Figure 2 and Figure 3 (The square standing on the peak): a test point that must be triggered when the protective switchgear carries the test current before the test time is reached.

[0180] Current-time limit: The (consistent) limit of the current-time value determined by the test point.

[0181] The (lower limit) current-time limit that does not trigger: the (consecutive) limit of the current-time value that the protective switching device is not allowed to trigger before (or at) it.

[0182] The (upper limit) current-time limit for triggering (already triggered): the (consistent) limit of the current-time value that the protective switching device must have triggered before (or at) it.

[0183] Range: The range of current-time values ​​determined by the current-time limit.

[0184] Triggered (already triggered) range: the range obtained by the (standard) test point, which requires the current to be safely interrupted.

[0185] Non-triggering range: The range obtained by the test point due to the requirement that the current must be safely carried.

[0186] Trigger range: The intermediate range between the non-triggered range and the triggered (already triggered) range.

[0187] Here, according to the present invention, different trigger characteristic curves can be realized by means of electronic measurement technology (current sensor unit) and digital algorithm (control unit) of novel electronic protection switchgear.

[0188] Figure 3 An example of how this can be implemented is shown. Three trigger characteristic curves or operating modes can be provided and selected on the protection switchgear through simplified setup possibilities: "Standard," "Sensitive," and "Robust."

[0189] The triggering behavior is defined by a corresponding digital algorithm (e.g., in the device firmware of the control unit). According to the present invention, it is now possible to retroactively change the triggering behavior of the protective switching device within existing standard limits.

[0190] This invention enables the possibility of a simple change to the triggering behavior of protective switchgear without altering the standardized triggering characteristics (used for electrical planning of the equipment).

[0191] Therefore, the possibility of installing electronic circuit protection switches / protection switchgear that conform to existing standards has been obtained.

[0192] Because it allows for changes to the triggering behavior without altering the standardized triggering scope (standardized triggering characteristics), even laypeople can use this possibility of change in a simplified way.

[0193] Although the invention has been described and illustrated in detail with reference to embodiments, the invention is not limited to the disclosed examples and other variations can be derived by those skilled in the art without departing from the scope of protection of the invention.

Claims

1. A protective switchgear for providing standard-compliant line protection for low-voltage AC circuits, the protective switchgear comprising: - Housing (GEH), the housing having at least one connector on the grid side and at least one connector on the load side, - A mechanically disconnecting contact unit (MK), which is connected in series with an electronic interruption unit (EU), wherein, The series connection is connected to at least one connector on the power grid side and to at least one connector on the load side. The mechanically disconnecting contact unit (MK) can be switched by either opening at least one contact to prevent current flow or closing at least one contact to allow current flow in the low-voltage AC circuit. - The electronic interruption unit (EU) can be switched via a semiconductor-based switching element to a high-ohmic state for preventing current flow or a low-ohmic state for current flow in the low-voltage AC circuit. - A current sensor unit (SI) for determining the magnitude of the current in the low-voltage AC circuit. - A control unit (SE), which is connected to the current sensor unit (SI), the mechanical disconnect contact unit (MK), and the electronic interrupt unit (EU). Specifically, when the specific trigger current-time limit value for forming the trigger curve is exceeded, the flow of the initiation current is avoided. - Standards for electrical installation materials predefine triggering current-time limits that must be avoided when current flows in the low-voltage AC circuit and non-triggering current-time limits that must be allowed to carry current flows in the low-voltage AC circuit. These triggering and non-triggering current-time limits mark the triggering range. - The specific trigger current-time limit value is within the trigger range. - The protective switchgear is designed to be, This allows for the selection of at least one first trigger curve (robust) and one second trigger curve (sensitive) within the trigger range. This allows for the selection of different trigger behaviors within a trigger range that is marked in a standard manner.

2. The protective switchgear (SG) according to claim 1. Its features are, The mechanical disconnect contact unit (MK) is associated with the connector on the load side, and the electronic interrupt unit (EU) is associated with the connector on the power grid side.

3. The protective switchgear (SG) according to claim 1 or 2. Its features are, It is equipped with two grid-side connectors and at least one load-side connector.

4. The protective switchgear (SG) according to claim 1 or 2. Its features are, It is equipped with two grid-side connectors and two load-side connectors.

5. The protective switchgear (SG) according to any one of the preceding claims. Its features are, At least one contact of the mechanically disconnecting contact unit (MK) can be disconnected by the control unit (SE), but cannot be closed by the control unit.

6. The protective switchgear (SG) according to any one of the preceding claims. Its features are, The mechanically disconnecting contact unit (MK) can be operated via a mechanical handle (HH) to switch the at least one contact open or closed.

7. The protective switchgear (SG) according to claim 6. Its features are, At least one contact of the mechanical disconnect contact unit (MK) has a free-switch function, which allows the at least one contact to be disconnected by the control unit (SE) even if the mechanical handle (HH) is locked.

8. The protective switchgear (SG) according to any one of the preceding claims. Its features are, For the aforementioned trigger range, a third trigger curve (standard) can be selected within the trigger range. This allows for the selection of additional triggering behaviors within the triggering range.

9. The protective switchgear (SG) according to any one of the preceding claims. Its features are, For the aforementioned trigger range, at least one additional trigger curve can be selected within the trigger range. This allows for the selection of at least one additional triggering behavior within the triggering range.

10. The protective switchgear (SG) according to any one of the preceding claims. Its features are, The standard in question is DIN EN 60898, specifically DIN EN 60898-1 or DIN EN60898-2, for line protection switches, or a manufacturer-specific standard.

11. The protective switchgear (SG) according to any one of the preceding claims. Its features are, The control unit has a microprocessor and a memory. The trigger curve is stored in the control unit.

12. The protective switchgear (SG) according to any one of the preceding claims. Its features are, The protective switchgear is designed to be, This prevents the triggering of current flow through a high-ohmic state of the switching element of the electronic interrupt unit (EU). In particular, when at least one contact of the mechanically disconnecting contact unit (MK) remains closed.

13. A method for protecting a switchgear, said switchgear being used to provide standard-compliant line protection for low-voltage AC circuits. - When the specific trigger current-time limit value that forms the trigger curve is exceeded, the protection switching device is activated to prevent current flow. - Standards for electrical installation materials predefine triggering current-time limits that must be avoided when current flows in the low-voltage AC circuit and non-triggering current-time limits that must be allowed to carry current flows in the low-voltage AC circuit. These triggering and non-triggering current-time limits mark the triggering range. - The specific trigger current-time limit value is within the trigger range. - For the trigger range, at least one first trigger curve (robust) and one second trigger curve (sensitive) can be selected within the trigger range. This allows for the selection of different trigger behaviors within a trigger range that is marked in a standard manner.

14. The method according to claim 13, Its features are, For the aforementioned trigger range, a third trigger curve (standard) can be selected within the trigger range.

15. The method according to claim 13 or 14, Its features are, The protection switchgear is triggered to prevent current flow by a high-ohmic state of the switching element of the electronic interrupt unit (EU). In particular, when at least one contact of the mechanically disconnecting contact unit (MK) remains closed.

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