Withdrawable summation current transformers, residual current circuit breakers and installation methods

Description

[0001] The invention relates to a withdrawable summation current transformer for a residual current device consisting of multiple modules, for example, an RCBO or FI / LS. Furthermore, the invention relates to a modular residual current device with such a withdrawable summation current transformer and an assembly method for such a residual current device.

[0002] Electromechanical protective devices – such as circuit breakers, miniature circuit breakers, residual current devices, and arc or fire protection switches – are used to monitor and protect electrical circuits and are used primarily as switching and safety elements in electrical power supply and distribution networks. To monitor and protect the electrical circuit, the protective device is electrically connected to an electrical line of the circuit to be monitored via two or more connection terminals in order to interrupt the electrical current in the respective monitored line if necessary. For this purpose, the protective device has at least one switching contact, which can be opened when a predefined condition occurs – for example, when a short circuit or fault current is detected – to disconnect the monitored circuit from the electrical network.Such protective switching devices are also known as modular devices in the field of low-voltage technology.

[0003] Circuit breakers are specifically designed for high currents. A miniature circuit breaker (MCB), also known as a miniature circuit breaker (LSB), is a so-called overcurrent protection device in electrical installations and is used primarily in low-voltage networks. Circuit breakers and miniature circuit breakers guarantee safe shutdown in the event of a short circuit and protect consumers and systems from overload, for example, from damage to electrical cables caused by excessive heating resulting from excessive electrical current. They are designed to automatically shut down a monitored circuit in the event of a short circuit or overload, thus isolating it from the rest of the power system.Circuit breakers and miniature circuit breakers are therefore used primarily as switching and safety elements for monitoring and protecting electrical circuits in electrical power grids. Miniature circuit breakers are already known in principle from the publications DE 10 2015 217 704 A1, EP 2 980 822 A1, DE 10 2015 213 375 A1, DE 10 2013 211 539 A1, and EP 2 685 482 B1.

[0004] To interrupt a single phase line, a single-pole circuit breaker is usually used, which typically has a width of one module (approximately 18 mm). For three-phase connections, three-pole circuit breakers are used (as an alternative to three single-pole switching devices), which accordingly have a width of three modules (approximately 54 mm). Each of the three phase conductors is assigned a pole. iea switching point is assigned. If the neutral conductor is to be interrupted in addition to the three phase conductors, the devices are referred to as four-pole devices, which have four switching points: three for the three phase conductors and one for the common neutral conductor.

[0005] In addition, there are compact circuit breakers which, with a housing width of only one module, provide two switching contacts for each connecting cable, i.e. either for two phase cables (compact circuit breakers of type 1+1) or for one phase cable and the neutral conductor (compact circuit breakers of type 1+N).

[0006] Such compact protective switching devices in a narrow design are known in principle, for example from the documents DE 10 2004 034 859 A1, EP 1 191 562 B1 or EP 1 473 750 A1.

[0007] A residual current device (RCD) is a protective device designed to provide protection against dangerous fault currents in an electrical system. Such a fault current—also known as a differential current—occurs when a live wire makes electrical contact with ground. This occurs, for example, when a person touches a live part of an electrical system: in this case, the current flows as a fault current through the person's body to earth. To protect against such body currents, the residual current device (RCD) must quickly and safely disconnect all poles of the electrical system from the power grid when such a fault current occurs.In common usage, the terms FI circuit breaker (short: FI switch), residual current circuit breaker (short: DI switch) or RCD (for "Residual Current Protective Device") are used interchangeably instead of the term "residual current circuit breaker".

[0008] A further distinction is made between mains voltage-dependent and mains voltage-independent residual current circuit breakers: while mains voltage-dependent residual current circuit breakers have control electronics with a release that relies on an auxiliary or mains voltage to fulfil their function, mains voltage-independent residual current circuit breakers do not require an auxiliary or mains voltage to implement the release function, but usually have a somewhat larger summation current transformer to implement the mains voltage-independent release, which can generate a larger induction current in the secondary winding.

[0009] There are also device designs that combine the functionality of a residual current device with that of a miniature circuit breaker: such combined protective switching devices are known in German as FI / LS or in English-speaking countries as RCBO (residual current operated circuit-breaker with overcurrent protection). Compared to separate residual current devices and miniature circuit breakers, these combination devices have the advantage that each circuit has its own residual current device: normally, a single residual current device is used for multiple circuits. If a fault current occurs, all protected circuits are switched off. By using RCBOs, only the affected circuit is switched off.

[0010] To detect such a fault or differential current, the magnitude of the current in a cable leading to an electrical consumer, e.g. a phase cable, is compared with the magnitude of the current in a cable returning from the electrical consumer, e.g. a neutral conductor, using a so-called summation current transformer. This has a ring-shaped magnetic core through which the primary conductors (outgoing and returning electrical cables) are passed. The magnetic core itself is wound with a secondary conductor or secondary winding. When there is no fault current, the sum of the electrical currents flowing to the consumer is equal to the sum of the electrical currents flowing back from the consumer. If the currents are vectorial, i.e. direction-related orsigned, it follows that the signed sum of the electrical currents in the forward and return lines in the fault-free state is zero: no induced current is induced in the secondary conductor. In contrast, in the case of a fault or differential current that flows to earth, the sum of the forward and return electrical currents recorded in the summation current transformer is not zero. The resulting current difference leads to a voltage proportional to the current difference being induced in the secondary winding, causing a secondary current to flow in the secondary winding. This secondary current serves as a fault current signal and, once a predetermined value is exceeded, leads to the protective switching device being triggered and consequently - by opening at least one switching contact of the protective switching device - to the shutdown of the correspondingly protected circuit.

[0011] A line-voltage-independent residual current device with a narrow design, i.e., with a width of only one module, is known, for example, from published patent application DE< 10 2018 202 204 A1. The residual current device has two current path areas arranged side by side in a common insulating housing in the width direction. During assembly, a pre-assembled summation current transformer assembly is inserted into a middle section of the insulating housing via one of the wide sides, with the installation space required for the summation current transformer being located in both the first and second current path areas.

[0012] Furthermore, the patent specification DE 691 02 583 T2 discloses a residual current transformer for a residual current circuit breaker, the housing of which consists of two half-shells, to each of which two breakable clips are formed, which, when not broken out, enable a snap connection of the two half-shells and can be broken out after the assembly of the primary conductors in order to achieve the most compact design possible.

[0013] Especially with multi-pole residual current devices—whether as a pure residual current device or as a combined device design such as a residual current device (RCD) / MCB (RCD / MCB) or RCBO (RCD / MCB)—the relatively thick primary conductors must be manually threaded through the ring-shaped magnetic core during assembly of the summation current transformer. Especially with compact protective or measuring devices that have limited installation space, such assembly is comparatively complex and must be carried out manually.

[0014] It is therefore the object of the present invention to provide a withdrawable summation current transformer for a residual current circuit breaker formed from several individual modules, a modular residual current circuit breaker with such a withdrawable summation current transformer and an assembly method for such a residual current circuit breaker, which are characterized by simplified assembly.

[0015] This object is achieved according to the invention by the withdrawable summation current transformer for a residual current circuit breaker formed from several individual modules, the modular residual current circuit breaker with such a withdrawable summation current transformer, and the assembly method for such a residual current circuit breaker according to the independent claims. Advantageous embodiments are the subject of the dependent claims.

[0016] The withdrawable summation current transformer according to the invention for a residual current circuit breaker formed from several structurally stable individual modules has a magnetic core accommodated and held in a housing, through the opening of which at least two rigid primary conductors are passed. Each of the primary conductors has a first end and a second end for contacting a connection element of the module uniquely assigned to the respective primary conductor. Furthermore, the withdrawable summation current transformer has at least one guide contour that enables guided insertion of the withdrawable summation current transformer along an insertion direction into a laterally open installation space extending over the several modules of the residual current circuit breaker, wherein the ends of the primary conductors assume a predefined position relative to their respective associated connection elements after insertion.

[0017] The use of the withdrawable summation current transformer according to the invention has the advantage that the rigid primary conductors are routed through the magnetic core before the summation current transformer is installed in the residual current device – and thus outside the residual current device housing. The magnetic core can be tubular or ring-shaped. If it is wound from strip material, it is referred to as a toroidal core. Furthermore, the magnetic core can be housed and held in its own protective sheath.

[0018] The term "rigid" refers to the primary conductors having inherent stability, allowing them to retain their shape. In particular, the first and second ends of the primary conductors, which are contacted with a respective connection element of the residual current device in a later assembly step, each have a predefined position—adjacent to the respective associated connection element—after the withdrawable summation current transformer has been installed, i.e., after the withdrawable summation current transformer has been inserted into the designated installation space of the residual current device.

[0019] The number of primary conductors to be passed through the magnetic core corresponds to the number of individual modules of the residual current device, with each module of the residual current device being uniquely assigned one of the primary conductors: For a two-pole residual current device consisting of two modules, two primary conductors are required - one for contacting a neutral conductor, another for contacting a phase conductor. For a three-pole residual current device consisting of three modules, three primary conductors are required - one for contacting the neutral conductor, two further conductors each for contacting a phase conductor. For a four-pole residual current device consisting of four modules, there are four primary conductors: one for contacting the neutral conductor, three further conductors each for contacting a phase conductor.

[0020] The guide contours are formed on the housing of the withdrawable summation current transformer and serve to facilitate the insertion of the withdrawable summation current transformer in a insertion direction into a laterally open installation space extending across the multiple modules of the residual current circuit breaker. In particular, they serve to prevent the first and second ends of the primary conductors from colliding with the connection elements of the residual current circuit breaker that protrude into the installation space during insertion in the insertion direction. The guide contours can, for example, be webs, lugs, or stop surfaces formed on the housing, which enable a predefined spatial positioning of the withdrawable summation current transformer during the insertion movement.

[0021] In an advantageous refinement of the withdrawable summation current transformer, each primary conductor is routed through the opening of the magnetic core at least twice. This means that each primary conductor must be returned at least once on the outside of the withdrawable summation current transformer. The resulting higher number of turns in the primary conductors allows for a higher secondary current on the secondary side of the withdrawable summation current transformer.

[0022] In a further advantageous development of the withdrawable summation current transformer, the first and second ends of each primary conductor are oriented opposite each other transversely to the insertion direction. The opposite orientation of the first and second ends of each primary conductor allows for a certain distance between the primary conductor ends, effectively preventing contact errors such as contacting, incorrect contacts, etc. Each primary conductor is uniquely assigned a module of the residual current device. The two ends of a primary conductor are thus "at the same height" in the insertion direction, so that after insertion, they are positioned within their assigned module and adjacent to their respective connection element.

[0023] In a further advantageous development of the withdrawable summation current transformer, the first ends of the primary conductors are arranged one behind the other in the insertion direction. The second ends of the primary conductors are also arranged one behind the other in the insertion direction. By arranging the first ends of the primary conductors and the second ends of the primary conductors one behind the other in a row, collisions between the primary conductor ends and components of the residual current device that protrude into the installation space can be avoided.

[0024] In a further advantageous development of the withdrawable summation current transformer, the housing has several guide ribs on its exterior for guiding the primary conductors. These guide ribs hold the primary conductors in a predefined position while winding the magnetic core. This allows the external dimensions of the withdrawable summation current transformer to be reliably maintained, which is advantageous given the limited space within the installation compartment, as it ensures that the maximum available installation space is not exceeded.

[0025] In a further advantageous development of the withdrawable summation current transformer, the ends of the primary conductors are arranged at a distance from the housing downwards, i.e., from the front side to the mounting side. This ensures better accessibility to the primary conductor ends, which is particularly advantageous for the subsequent joining process (welding, soldering). This also minimizes the energy input during joining of the primary conductor ends, thus reducing the risk of damage to the withdrawable summation current transformer—especially the magnetic core.

[0026] In a further advantageous development, the withdrawable summation current transformer has a cuboid-shaped outer contour. This allows for a compact design, with the cuboid-shaped outer contour corresponding to the essentially cuboid-shaped installation space of the residual current device.

[0027] The modular residual current device according to the invention comprises a first module designed as an MCB module, in which a current path for contacting a phase conductor is arranged, which has a switching contact and a switching mechanism with a magnetic and a thermal tripping system for interrupting the switching contact. Furthermore, the residual current device comprises a second module designed as an RCD module, in which a current path for contacting a neutral conductor is arranged. Both modules each comprise an insulating housing with a front side, a fastening side arranged opposite the front side, and narrow and wide sides connecting the front and fastening sides, and are arranged side by side.The insulating housings each have a plug-in opening extending from one broad side to the other, whereby, when the MCB module is combined with the RCD module, a cross-module installation space is formed in which a cross-module plug-in summation current transformer of the type described above is accommodated and held.

[0028] The residual current circuit breaker according to the invention is a combined device design in which the functionality of a pure residual current circuit breaker is combined with the functionality of a circuit breaker: in German, such combined protective devices are referred to as FI / LS (residual current / line protection), in English-speaking countries the term RCBO (for residual current operated circuit-breaker with overcurrent protection) is used.

[0029] The term "modular" refers to the fact that the residual current device is constructed from two individual modules – an MCB module and an RCD module. Both modules are structurally stable, enclosed modules, each with its own insulating housing and a plug-in opening. Once the two modules are mounted, wide side to wide side, they form a cross-module installation space for accommodating and installing the plug-in summation current transformer. Internally, each module has a primary conductor current path – for the neutral conductor in the case of the RCD module, and for a phase conductor in the MCB module. The assemblies and components required to implement the functionality of each module – a switching contact, switching and tripping mechanism (for short circuits and thermal overloads in the MCB module, for residual currents in the case of residual currents), arc quenching equipment, etc. – are also included.- are arranged, i.e. accommodated and held, in the respective module.

[0030] The installation space is arranged off-center between the two narrow sides, i.e. shifted towards one of the two narrow sides, and is accessible from the outside via the two wide sides of each module. Once the two modules have been assembled (wide side to wide side), the two outer wide sides can be closed using suitable locking elements such as covers or flaps. The off-center arrangement has the advantage that free installation space is available in this area of ​​the modules forming the residual current device, which can be used to install a large-volume assembly such as the withdrawable summation current transformer. In this way, the modules - and thus the residual current device - can be kept compact, so that each module has a width of just one pitch unit, which corresponds to approximately 18mm.The residual current circuit breaker accordingly has a width of one pitch unit per module - i.e. two pitch units for a two-pole device consisting of two modules.

[0031] In an advantageous development, the modular residual current circuit breaker has at least one further module, which is designed as an MCB module and arranged next to the first module. By adding further MCB modules, three-pole (one further MCB module) or four-pole (two further MCB modules) FI / LS or RCBO devices can be easily implemented. Only the summation current transformer, which is to be inserted into the common installation space across all modules, needs to be modified accordingly, i.e. an additional primary conductor is required for each additional module. The individual modules are arranged side by side and fastened to one another using suitable connecting elements - for example clamps, rivets or snap connections.

[0032] The assembly method according to the invention for a modular residual current circuit breaker of the type described above comprises the steps a) Attaching at least one MCB module to an RCD module so that a cross-module installation space is formed; b) Inserting a withdrawable summation current transformer formed in the manner described above into the installation space in an insertion direction (R1); c) Establishing joining connections between the first and second ends of the primary conductors and a connection element of the respective module that is uniquely assigned to the respective primary conductor end. The assembly method according to the invention for a modular residual current device can significantly reduce assembly effort, particularly because the primary conductors no longer have to be manually threaded through the opening of the residual current transformer within the housing of the residual current device, but can be pre-assembled outside the housing. This allows steps b) "inserting into the installation space" and c) "creating a joining connection" to be carried out at least partially automatically. During joining, the components / joining parts to be joined – in this case, the ends of the primary conductors with the respective associated connection element – ​​are permanently connected. The joining connection can be implemented as a form-fitting, force-fitting, or material-fitting connection.

[0033] In an advantageous further development, the assembly method comprises the additional step b1) moving the withdrawable summation current transformer in an engagement direction (R2) oriented transversely to the insertion direction,

[0034] The additional step b1) is performed before the "production of joint connections." In this way, the ends of the primary conductors are brought into close proximity with the respective connection element only after the summation current transformer has been inserted into the installation space, so that they can then be easily connected. This reliably prevents collisions during insertion.

[0035] In a further advantageous development of the assembly process, step c) "Creating joints" is performed thermally by soldering or welding. These thermal joining processes, soldering and welding, can create a solid, sometimes highly heat-resistant, and secure joint between the primary conductor ends and the respective associated connecting element.

[0036] In the following, exemplary embodiments of the withdrawable summation current transformer according to the invention, the modular residual current device according to the invention, and the assembly method according to the invention are explained in more detail with reference to the attached figures. In the figures: Figures 1 and 2 schematic representations of the modular residual current circuit breaker according to the invention; Figure 3 a first embodiment of the withdrawable sum current transformer according to the invention; Figures 4 and 5 schematic side views of the Figure 3corresponding residual current circuit breaker in different assembly states; Figure 6 shows a further embodiment of the withdrawable summation current transformer according to the invention; Figure 7 shows a further embodiment of a Figure 6 corresponding modular residual current circuit breaker according to the invention; Figure 8 shows a schematic representation of the assembly method according to the invention.

[0037] In the various figures of the drawing, identical parts are always provided with the same reference symbol. This description applies to all drawing figures in which the corresponding part can also be seen.

[0038] In the Figures 1 and 2The basic structure of the modular residual current device 1 according to the invention is shown schematically in two different views. The four-pole residual current device 1, designed as a residual current device (RCD) or RCBO, is composed of four individual modules, an RCD module 2 (shown on the right in Figure 1a) and three MCB modules 3, each of which has an independent, structurally stable insulating housing 10.

[0039] The insulating housings 10 are each designed in a narrow design and have a width B of one pitch unit (1TE, corresponding to approximately 18mm). The outer dimensions defining the envelope surfaces are formed by a front side 11, a fastening side 12 arranged opposite the front side 11, and narrow sides 13 and wide sides 14 connecting the front and fastening sides 11, 12. In the area of ​​the narrow sides, screw terminals 19 for contacting mains-side or load-side connecting conductors (not shown) are accommodated and held in the respective insulating housing 10 of the respective module. For manual actuation, each of the modules 2, 3 has an actuating element 23 arranged in the area of ​​its front side 11. Joint actuation of the individual actuating elements 23 is realized by means of a connecting element 24 coupling the individual actuating elements 23.

[0040] Typically, narrow-profile insulating housings 10 comprise two half-shells, which are joined together at the end of the assembly of the low-voltage protective device 1 using suitable fasteners, such as rivets or snap-in connections, to form a circumferential joint line. Each half-shell includes one of the wide sides 14 as well as parts (in whole or in full) of the front, mounting, and narrow sides 11, 12, and 13.

[0041] In the broad sides 14 of each of the insulating housings 10, a plug-in opening is formed, which extends orthogonally to the broad sides 14 from one broad side 14 to the other, thereby forming an installation space 16. Electrical connection elements 26 of the respective module 2, 3 protrude laterally into the installation space 16. By assembling the individual modules 2, 3 to form a multi-pole device, here the four-pole FI / LS or RCBO, a cross-module installation space 16 is formed from the installation spaces 16, in which a large-volume assembly, for example a plug-in summation current transformer 100 (see Figure 3), i.e., can be accommodated and held. The installation space 16 is positioned off-center, i.e., shifted toward one of the narrow sides 13, in the insulating housing 10 and is accessible via each of the two wide sides 14. To protect against environmental influences such as dust or moisture, the insertion openings can be closed by means of suitable closure elements, for example a cover 25.

[0042] In Figure 3 A first embodiment of the plug-in summation current transformer 100 according to the invention is shown schematically in a perspective view. This has a ring-shaped or tubular magnetic core 102, which is accommodated and held in a housing 101 of the plug-in summation current transformer 100. Since this is a summation current transformer for the Figures 1 and 2In the known four-pole residual current circuit breaker of the FI / LS or RCBO type, four primary conductors 110, 120, 130, 140 are passed through the opening of the magnetic core. Each of the primary conductors 110, 120, 130, 140 has a first end 111, 121, 131, 141 and a second end 112, 122, 132, 142. The first and second ends of each primary conductor 110, 120, 130, 140 are oriented opposite to each other transversely to an insertion direction R1, ie the ends each point outwards transversely to the insertion direction, wherein the first ends 111, 121, 131, 141 and the second ends 112, 122, 132, 142 each form a row extending in the insertion direction.

[0043] In order to facilitate the insertion of the withdrawable summation current transformer 100 into the installation space 16 and to avoid collisions of the first and second ends 111, 112, 121, 122, 131, 132, 141, 142 of the primary conductors 110, 120, 130, 140 with the connection elements 26 projecting into the installation space 16, the withdrawable summation current transformer 100 has guide contours 108 which, when the withdrawable summation current transformer 100 is inserted into the installation space 16, engage on corresponding contact surfaces 17 formed there (see Figures 4 and 5 ). In this way, a defined relative movement of the withdrawable summation current transformer 100 relative to the residual current circuit breaker 1 can be realized, which effectively prevents a collision of the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142 with the connection elements 26.

[0044] To achieve better magnetic induction of the withdrawable summation current transformer 100 – and thus a higher current flow in the secondary winding – each of the primary conductors 110, 120, 130, 140 is passed twice through the magnetic core 102 – and correspondingly returned to the outside of the housing 101. To also hold the primary conductors 110, 120, 130, 140 in a predefined position on the outside of the housing 101, the withdrawable summation current transformer 100 has several guide webs 109 through which the primary conductors 110, 120, 130, 140 are guided at a distance from one another.

[0045] In the Figures 4 and 5 is the one from the Figures 1 and 2 known residual current circuit breaker 1 with the mounted therein, made of Figure 3 known withdrawable summation current transformer 100 is shown schematically in two side views, which show different assembly states. Figure 4shows the residual current device 1 with the withdrawable summation current transformer 100 inserted into the installation space 16 immediately at the end of the insertion movement in the insertion direction R1. Figure 5 the withdrawable summation current transformer 100 is offset in a second direction, the insertion direction R2, which is oriented from the fastening side 12 to the front side 11 - and thus transversely to the insertion direction R1 - so that the first and second ends 111, 112, 121, 122, 131, 132, 141, 142 of the primary conductors 110, 120, 130, 140 are located directly in the region of the connection element 26 assigned to them.

[0046] In the Figures 4 and 5In the exemplary embodiment shown, the connection elements 26 have U-shaped receptacles for the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142, which serve to mechanically secure the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142: if the first and second ends 111, 112, 121, 122, 131, 132, 141, 142 of the primary conductors 110, 120, 130, 140 are located directly in the region of the U-shaped receptacle of the connection element 26 assigned to them in each case, the U-shaped receptacles can be pressed together by means of a tool suitable for this purpose, whereby a mechanically stable connection is initially realized between the respective primary conductor end and the connection element 26 assigned to it. In order to achieve a good electrical conductivity, this connection can then be thermally joined, for example by soldering, brazing or welding.

[0047] To enable better access to the connection elements 26, the insulating housings 10 of the individual modules 2, 3 have closable mounting openings (not shown) on their mounting side 12, which allow access to the installation space and are located directly below the connection elements 26. In this way, the mechanical and / or thermal joining connection can be carried out from the mounting side 12 using standard tools.

[0048] In the representations of the Figures 4 and 5 Furthermore, the two contact surfaces 17, which guide the withdrawable summation current transformer 100 during its insertion movement in the engagement direction R2 and thereby prevent the first and second ends 111, 112, 121, 122, 131, 132, 141, 142 of the primary conductors 110, 120, 130, 140 from colliding with the connection elements 26 during the insertion movement in the direction R1, can be clearly seen.

[0049] The primary conductors 110, 120, 130, 140 are initially guided downwards centrally below the housing 101 of the withdrawable summation current transformer 100, before the first and second ends 111, 112, 121, 122, 131, 132, 141, 142 are angled outwards. In this way, a free space defined by the distance is created between the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142 and the housing 101, into which the connection elements 26 protrude during the insertion movement of the withdrawable summation current transformer 100 without colliding with the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142.

[0050] In the Figures 6 and 7 An alternative embodiment of a withdrawable summation current transformer 100' according to the invention and of a corresponding, alternative modular residual current device 1' are schematically shown. Figure 6shows the alternative plug-in summation current transformer 100', which is used for a two-pole residual current device 1' (see Figure 7 ) and therefore has only two primary conductors 110', 120', which in turn are passed twice through the magnetic core 102'. In contrast to the Figures 1 to 5 In the first embodiment shown, the magnetic core 102' is now erected so that the primary conductors 110', 120' from top to bottom - iefrom the front side 11 to the fastening side 12 through the opening of the magnetic core 102'. The first and second ends 111', 112', 121', 122' of the two primary conductors 110' and 120' are in turn angled outwards, so that between the primary conductor ends 111', 112', 121', 122' and the housing 101' of the two-pole withdrawable summation current transformer 100' there is a free space defined by the distance to the magnetic core 102', into which the connection elements 26 protrude without colliding with the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142 during the insertion movement.

[0051] The Figure 7 The two-pole residual current device 1' shown in a side view has only two modules - an RCD module 2 and an MCB module 3 (see Figures 1 and 2 ) - which are structurally equivalent to modules 2 and 3 of the Figures 1 to 5correspond to the modules 2, 3 shown and described and each have an independent, structurally stable insulating housing 10. This design makes it possible to combine modular protective switching devices, for example two-, three-, or four-pole FI / LS residual current circuit breakers 1, 1', with cross-module assemblies such as the withdrawable summation current transformer 100, 100', whereby the respective withdrawable summation current transformer 100, 100' is specifically adapted to the modular conditions of the respective residual current circuit breaker 1, 1'.

[0052] The assembly method according to the invention for a modular residual current device 1, 1' of the type described above is briefly explained below with reference to the illustration in Figure 8: In a first step S1, at least one MCB module 3 is attached to an RCD module 2, so that a residual current device 1, 1' with a cross-module installation space 16 is formed. Using only one MCB module 3 results in a two-pole residual current device 1'; installing three MCB modules results in a four-pole residual current device 1.

[0053] In a second step S2, a withdrawable summation current transformer 100, 100' matching the respective residual current circuit breaker 1, 1' is inserted into the cross-module installation space 16 in an insertion direction R1. The first ends 111, 121, 131, 141, 111', 121' and the second ends 112, 122, 132, 142, 112', 122' of the primary conductors 110, 120, 130, 140, 110', 120' are positioned adjacent to the respective connection element 26 assigned to them.

[0054] Finally, in a third step S3, joining connections are established between the first ends or second ends 111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122' of the primary conductors 110, 120, 130, 140, 110', 120' and the connecting element 26 of the respective module 2, 3, which is uniquely assigned to the respective primary conductor end 111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122'. This means that the respective joining partners are firmly connected to one another. The joining connection can be mechanical, for example, by clamping or crimping, or thermal, such as soldering, brazing, or welding. Combinations of the various joining methods are also possible.

[0055] If the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122' are not yet in the immediate vicinity of the respectively assigned connection elements 26 after the second step, the insertion of the withdrawable summation current transformer 100, 100' in the insertion direction R1 into the cross-module installation space 16, an additional step S2a is required before joining (step S3), in which the withdrawable summation current transformer 100, 100' is moved in an engagement direction R2 oriented transversely to the insertion direction until the primary conductor ends 111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122' are located in the immediate vicinity of the connecting element 26 assigned to them.

[0056] The installation sequence is independent of whether it is a two-pole, three-pole or four-pole FI / LS residual current device 1, 1'. List of reference symbols:

[0057] 1, 1'Residual current circuit breaker 2RCD module 3MCB module 10Insulated housing 11Front 12Mounting side 13Narrow side 14Wide side 16Installation space 17Contact surface 19Screw terminal 23Actuating element 24Connecting element 25Cover 26Connecting element 100, 100'Summation current transformer 101, 101'Housing 102, 102'Magnet core 108, 108'Guide contour 109, 109'Guide web 110, 110'Primary conductor 111, 111'First end 112, 112'Second end 120, 120'Primary conductor 121, 121'First end 122, 122'Second end 130Primary conductor 131First end 132Second end 140Primary conductor 141First end 142Second end R1Insertion direction R2Insertion direction S1first step S2second step S2additional step S3third step

Claims

1. Slide-in summation current transformer (100, 100') for a residual-current circuit breaker (1, 1') formed from a plurality of structurally mechanically stable modules (2, 3), - having a housing (101, 101') in which a magnetic core (102, 102') is received and held and through the opening in which at least two rigid primary conductors (110, 120, 130, 140, 110', 120') are passed, - wherein each of the primary conductors (110, 120, 130, 140, 110', 120') has a first end (111, 121, 131, 141, 111', 121') and a second end (112, 122, 132, 142, 112', 122') for contact-connection with a respective connection element (26) of the module (2, 3) uniquely assigned to the respective primary conductor (110, 120, 130, 140, 110', 120'), - wherein the slide-in summation current transformer (100, 100') has at least one guide contour (108, 108'), which allows the slide-in summation current transformer (100, 100') to be slid in a guided manner along a slide-in direction (R1) into a laterally open installation space (16) extending over the plurality of modules (2, 3) of the residual-current circuit breaker (1, 1'), wherein the ends of the primary conductors (111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122'), after the slide-in operation, assume a predefined position in relation to the connection elements (26) respectively assigned to them.

2. Slide-in summation current transformer (100, 100') according to Claim 1, wherein each of the primary conductors (110, 120, 130, 140, 110', 120') is guided through the opening in the magnetic core (102, 102') at least twice.

3. Slide-in summation current transformer (100, 100') according to either of the preceding claims, wherein the first and the second end (111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122') of each primary conductor (110, 120, 130, 140, 110', 120') are oriented oppositely to each other transversely in relation to the slide-in direction (R1).

4. Slide-in summation current transformer (100, 100') according to any of the preceding claims, wherein the first ends (111, 121, 131, 141, 111', 121') of the primary conductors (110, 120, 130, 140, 110', 120') are arranged one behind the other in the slide-in direction (R1) and the second ends (112, 122, 132, 142, 112', 122') of the primary conductors (110, 120, 130, 140, 110', 120') are arranged one behind the other in the slide-in direction (R1).

5. Slide-in summation current transformer (100, 100') according to any of the preceding claims, wherein the housing (101, 101'), on its outside, has a plurality of guide bars (109, 109') for guiding the primary conductors (110, 120, 130, 140, 110', 120').

6. Slide-in summation current transformer (100, 100') according to any of the preceding claims, wherein the ends (111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122') of the primary conductors (110, 120, 130, 140, 110', 120') are arranged spaced apart from the housing (101, 101') downwardly, i.e. from the front side (11) to the mounting side (12).

7. Slide-in summation current transformer (100, 100') according to any of the preceding claims, wherein the slide-in summation current transformer (100, 100') has a cuboidal outer contour.

8. Modular residual-current circuit breaker (1, 1'), - comprising a first module (3), which is in the form of an MCB module and in which a current path is arranged for contact-connection with a phase conductor, which comprises a switching contact and a switching mechanism with a magnetic and a thermal tripping system for interrupting the switching contact, - comprising a second module (2), which is in the form of an RCD module and in which a current path is arranged for contact-connection with a neutral conductor, - wherein the two modules both have an insulating-material housing (10) with a front side (11), a mounting side (12) arranged opposite the front side (11), and with narrow and broad sides (13, 14) connecting the front and the mounting side (11, 12) and are arranged next to each other, - wherein the insulating-material housings (10) each have a slide-in opening extending from one broad side (14) to the other, as a result of which, when the MCB module (3) is combined with the RCD module (2), a module-overlapping installation space (16) is formed, in which a module-overlapping slide-in summation current transformer (100, 100') formed according to any of Claims 1 to 7 is received and held.

9. Modular residual-current circuit breaker (1, 1') according to Claim 8, comprising at least one further module (3), which is in the form of an MCB module and is arranged next to the first module (3).

10. Assembly method for a modular residual-current circuit breaker (1, 1') according to either of Claims 8 and 9, comprising the steps of: a) mounting at least one MCB module (3) on an RCD module (2), so that a module-overlapping installation space (16) is formed; b) sliding a slide-in summation current transformer (100, 100') formed according to any of Claims 1 to 7 into the installation space (16) in a slide-in direction (R1); c) establishing joining connections between the first and, respectively, second ends (111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122') of the primary conductors (110, 120, 130, 140, 110', 120') and a connection element (26) of the respective module (2, 3), the connection element being uniquely assigned to the respective primary conductor end (111, 112, 121, 122, 131, 132, 141, 142, 111', 112', 121', 122').

11. Assembly method according to Claim 10, comprising the additional step of: b1) moving the slide-in summation current transformer (100, 100') in an engagement direction (R2) oriented transversely in relation to the slide-in direction (R1), wherein the additional step b1) is executed before joining connections are established.

12. Assembly method according to either of Claims 10 and 11, wherein step c), establishing joining connections, is performed thermally by soldering or welding.