DE102011075456A1 - Core-balance current transformer for use in earth leakage circuit breaker e.g. relay, for detecting alternating current sensitive residual current in conductor circuit, has partitioning part with wall that is arranged in inner area of core - Google Patents

Abstract

The transformer (10) has a cylindrical magnetic core wrapped with a secondary conductor (12) i.e. enameled wire secondary conductor. The magnetic core comprises an inner area, which conducts multiple primary conductors (3) i.e. flexible wire primary conductors, of a conductor circuit. A partitioning part (20) protects the secondary conductor from damage while conducting the primary conductors in the inner area of the magnetic core. The partitioning part is formed in a cylindrical manner, and comprises a cylinder wall that is arranged in the inner area of the magnetic core.

Description

The invention relates to a summation current transformer for a residual current circuit breaker for detecting alternating current sensitive and / or pulse current sensitive fault currents in a line circuit, and a residual current circuit breaker having such a summation current transformer.

In the field of electrical installation technology, suitable devices such as residual current circuit breakers or residual current circuit breakers are used to detect a so-called residual current, in order to protect persons from the dangers which may arise when touching live parts of electrical installations. To protect against such dangers summation current transformer are used, with the aid of the differential current can be detected. Residual currents can occur if, for example, faulty insulation or, in the case of contact, a fault current flows through the human body against earth. To detect such a differential current, the magnitude of the current in a line leading to an electrical consumer, for example a phase line, is compared with the magnitude of the current in a line, for example a neutral conductor, which is returned by the electrical consumer. In the fault-free state, the sum of the electrical currents flowing to the consumer is equal to the sum of the returning electrical currents. If the currents are vectorial, i. directional or signed, added, it follows that the signed sum of the electrical currents in the forward and return lines in the zero-fault state is equal to zero. Conversely, in the case of a fault current flowing to earth, the sum of the currents flowing back and forth in the summation current transformer is not equal to zero. The resulting current difference leads to the triggering of the electrical installation device and as a result to the shutdown of the corresponding circuit.

A summation current transformer essentially consists of a magnetic core, which is usually ring-shaped or cylindrical. Such magnetic cores are wound from strip material usually made of crystalline or nanocrystalline soft magnetic tape and therefore also referred to as so-called "ring band cores". In order to achieve the necessary to trigger the electrical installation device power, however, a certain size and a certain mass of the magnetic core are required. Through the magnetic core, the leading and returning conductors of the circuit to be monitored, the so-called primary conductor, passed. If a fault current flows from one of the primary conductors towards earth, then the sum of currents flowing back and forth in the summation current transformer is no longer equal to zero. As a result, a current is induced in a secondary winding wound around the magnetic core. This induced secondary current triggers a mechanism of the residual current circuit breaker, such as a relay or a switch lock, whereby the primary lines are interrupted.

In German standardization, the terms "Residual Current Circuit Breaker" (FI) are used for mains-voltage-independent devices and "residual current circuit breaker" (DI) for mains-voltage-dependent devices. Such a distinction in mains voltage-independent and mains voltage-dependent electrical installation equipment is no longer made in English-speaking standards and in today's standard IEC and EN standards. In these recent regulations for electrical installations, residual current circuit breakers are uniformly managed under the superordinate term "RCD" (Residual Current Device). The terms "differential current" and "fault current" are therefore used interchangeably in the present description.

From the prior art, a plurality of electrical installation devices is known, which have a summation current transformer for detecting a difference or a fault current. The summation current transformer can be tubular or disk-shaped. However, in order to meet the required tripping power, a certain size of the summation current transformer is required, making it difficult to use in small electrical installation devices, for example in low-voltage modular devices. Furthermore, the space available for the summation current converter space is extremely reduced due to the required for the heat dissipation and the current flow thick primary conductor. Especially in residual current circuit breakers with higher rated currents, for example of 63 A, 80 A or 125 A, prevails in the housing of the residual current circuit breaker - especially in the area of the summation current transformer - increased space. Because of these tight spaces, the primary conductor strands often have to be bent excessively narrow, which entails the risk of damaging the strands and their insulation.

If the residual current circuit breaker further not only AC-sensitive, but also be designed pulse current sensitive, so large-volume transducers and - because of the high number of secondary conductor windings required - so-called enameled wire secondary conductors are required. This is a conductor wire coated with an insulating varnish, the thickness and the weight of the varnish insulation being very small in comparison with other conventionally used insulating materials having the same effect. The wound with enameled magnetic cores must be in the passage of the primary conductor, which stripped at their ends and Press welded and therefore sharp-edged, necessarily be protected by a so-called barrier to avoid damage to the sensitive secondary conductor when passing the Primärleiterlitzen. Summation current transformer with such a partition are for example from DE 10 2005 007 334 A1 known. By such a partition to protect the sensitive secondary conductor windings, however, increase the outer dimensions of the summation current transformer including the bulkhead. Since the space available for the entire summation current transformer is limited in the interior of the residual current circuit breaker just in compact devices available space is further reduced by the use of a partition of the space available for the wound magnetic core space.

The prior art also discloses the use of rigid, solid primary conductors rather than flexible strands. Although these are less thick and can be bent more closely, however, this requires an increased production cost. Furthermore, with a solid primary conductor no mutually movable parts can be connected to each other, as when using a solid primary conductor such movements can not be compensated. For this purpose, an additional strand is again required, which further increases the number of parts and the production cost.

In addition, to avoid false triggering at high currents due to unbalanced winding, the summation current transformer must pass over the entire toroid, i. over the entire circumference of the magnetic core, evenly distributed wound with secondary conductor wire. An accumulation of secondary conductor windings on a small sector, i. H. a small toroidal section of the summation current transformer, could lead to the induction of secondary voltages due to the proximity of the secondary windings to only one or two of the primary conductor strands at high rated currents, even though there is no fault current event, i. H. although the sum of the currents flowing in the primary lines passed through the summation current transformer added in signed form equal to zero. To avoid such false triggering due to an asymmetric secondary conductor winding, the magnetic core of the summation current transformer is uniformly wound over its entire circumference with secondary conductor wire.

It is the object of the present invention to provide a summation current transformer for detecting alternating current sensitive and / or pulse current sensitive fault currents and a corresponding residual current circuit breaker with such a summation current transformer, which are easy to manufacture and are characterized by a higher release capacity with the same volume.

This object is achieved by the summation current transformer and the residual current circuit breaker according to the independent claims. Advantageous embodiments are the subject of the dependent claims.

The summation current transformer according to the invention for a fault current circuit breaker, for detecting alternating current sensitive and / or pulse current sensitive fault currents in a line circuit, has a cylindrical magnetic core, which is wrapped with a secondary conductor. The magnetic core has an inner region which is designed to pass through a plurality of primary conductors of the line circuit. Furthermore, the summation current transformer has a partition which protects the secondary conductor from damage during the passage of the primary conductors in the inner region of the magnet core. In this case, the partition is substantially cylindrical and has only one cylinder wall, wherein the cylinder wall is arranged in the inner region of the magnetic core.

Since the partition does not surround the entire magnetic core with the secondary conductor wound around it, but only in an inner area of the magnetic core - i. in the opening of the summation current transformer - is arranged, on the one hand, the sensitive secondary conductor when performing the sometimes sharp-edged primary conductor strands are effectively protected by the opening of the summation current transformer against damage. The sensitive secondary conductor windings are thus spatially isolated from the primary conductors in the opening of the summation current transformer. On the other hand, the summation current transformer including the partition can be kept comparatively compact, since the partition only in the inner

Area of the magnetic core is arranged, the outer circumferential surface of the summation current transformer, i. the outer region of the wound magnetic core, but is not covered by the partition. As a result, the space required for the summation current transformer including the bulkhead is significantly reduced. The space gained in this way can in turn be used for a summation current transformer with a larger transformer core. As a result, the tripping accuracy and the tripping performance are further improved. Furthermore, the implementation of the primary conductor strands is significantly simplified.

The partition thus does not constitute a housing in which the wrapped magnetic core is completely accommodated, but merely a contact protection in the inner region of the magnetic core to damage the sensitive secondary conductor turns during so-called converter winding - ie when performing the relatively stiff, thick Primary conductor strands with their stripped and sharp-edged, since press-welded ends - to avoid. In the sections of the primary conductor, which are returned to the outside of the summation current transformer again, since the winding takes place outside of the device housing of the residual current circuit breaker, there is enough space to avoid endangering the secondary conductor windings in the region of the outer surface of the magnetic core during winding. In the region of the outer circumferential surface of the summation current transformer, ie the wound magnetic core, a danger to the secondary conductor windings is therefore not given by the stripped, sharp-edged ends of the Primärleiterlitzen. The isolated part of the primary conductor strands can thus be laid directly over the secondary conductor windings without any damage to the secondary conductor windings.

In an advantageous development of the summation current transformer, the partition has a collar at a first end of its axial longitudinal direction which at least partially covers a first end side of the annular or tubular magnetic core. With the help of the collar, it is possible to protect the frontal region of the wound magnetic core at least on one of the end faces against damage during insertion of the sharp-edged primary conductor strands. The end face is considered to be that part of the wound magnetic core which, at the edges of the annular or tubular magnetic core, defines the inner region, i. the inner circumferential surface of the wound magnetic core with the outer region, i. connects to the outer surface of the wound magnetic core.

In a further advantageous development of the summation current transformer, the partition has a plurality of extensions at a second end of its axial longitudinal extension direction, which extensions can be bent outward in a radial direction after insertion of the partition into the annular or tubular magnetic core. The extensions represent tabs, which are formed at the second end of the partition in the longitudinal direction of the cylindrical main body of the partition and juxtaposed lying on the circumference of the cylindrical base body. After the introduction of the barrier, they can be bent radially outward into the magnetic core wrapped with a secondary conductor, so that they protrude in the radial direction from the cylindrical base body of the partition. Advantageously, the tabs are bent fan-shaped in a large radius to the outside. In this way, the second end region of the wound magnetic core is at least partially covered by the partition; The sensitive secondary conductor windings are thus also protected in the region of the second end face of the summation current transformer from damage, for example due to careless handling.

In a further advantageous development of the summation current transformer, the partition has at least one guide element for guiding the primary conductors in an inner region of its cylindrical base body. With the aid of the guide element, the primary conductors can be held in a defined position after being passed through the opening of the summation current transformer. As a result, on the one hand facilitates the assembly; On the other hand, the tripping characteristic is improved by the exact positional positions of the primary conductor strands relative to the secondary conductor windings.

In a further advantageous development of the summation current transformer, the secondary conductor is uniformly distributed over an entire surface of the annular or tubular magnetic core wound. Due to the uniform winding of the secondary conductor windings over the entire surface of the magnetic core false tripping due to asymmetrical winding can be avoided. The symmetrical strength and thus the tripping accuracy of the summation current transformer are thereby significantly improved.

In a further advantageous development of the summation current transformer of the secondary conductor is designed as enamel wire secondary conductor. An enameled wire is a conductor wire coated with an insulating varnish, the thickness and weight of the varnish insulation being comparatively small compared with other, conventionally used insulating materials having the same effect. This results in the advantage that the summation current transformer can be kept relatively light, small and thus compact. This is particularly advantageous in residual current circuit breakers, which are not only AC sensitive, but also sensitive to pulse current, since the converters required for this purpose require a larger number of secondary conductor windings.

In a further advantageous development of the summation current transformer, the partition is formed in two or more parts. Multi-part enclosures are generally easier to assemble, reducing assembly costs.

In a further advantageous development of the summation current transformer, the two parts of the partition can be plugged together in the region of the cylinder wall. A two-part partition, the two parts of which are connectable by means of a plug connection, provides an easy-to-install option for protecting the secondary conductor windings. If the partition of the partition is arranged symmetrically, the partition can be made up of two identical parts be plugged together, which reduces the number of different parts. The procurement and storage costs are significantly reduced by the increased use of identical parts.

The fault current circuit breaker according to the invention is designed to detect alternating current-sensitive and / or pulse current-sensitive fault currents in a line circuit with the aid of a summation current transformer according to the invention. With regard to the advantages of the residual current circuit breaker according to the invention with such a summation current transformer, reference is first made to the statements made above on the summation current transformer according to the invention. By using the summation current transformer according to the invention in a residual current circuit breaker whose housing can be kept small and compact with significantly improved triggering power.

In a further advantageous development of the residual current circuit breaker, the primary conductors of the line circuit are formed as flexible strands, which are guided by the magnetic core of the summation current transformer. The use of flexible primary conductor strands instead of rigid conductors has the advantage that they do not have to be correspondingly bent and are relatively cumbersome to assemble. The manufacturing costs are thereby significantly reduced. Furthermore, the use of flexible strands allows a compensation of relative movements of the parts connected by means of the respective strand; this is also not possible when using rigid conductors.

In a further advantageous refinement of the residual current circuit breaker, the primary conductors already have stripped ends before being passed through the magnet core. If the primary conductor strands are already removed prior to assembly, i. stripped before passing through the opening of the summation current transformer, this operation can be done automatically before assembly. Further work steps on the already wound transducer module are therefore no longer required. The manufacturing costs are further reduced. The same applies to the case where the primary conductor strands are already press-welded at their ends prior to assembly.

Embodiments of the summation current transformer according to the invention and of the residual current circuit breaker according to the invention will be explained in more detail below with reference to the accompanying figures. In the figures are:

1 a schematic representation of the residual current circuit breaker according to the invention with mounted summation current transformer;

2A and 2 B schematic representations of the bulkhead of the summation current transformer according to the invention;

3A to 3C schematic representations of several assembly steps of the summation current transformer according to the invention;

4A to 4D schematic representations of alternative embodiments of the partitioning of the summation current transformer;

5A and 5B schematic representations of an alternative embodiment of the summation current transformer and the residual current circuit breaker;

6 a schematic representation of the size of the summation current transformer according to the invention in comparison to the size of a summation current transformer with conventional Schottung.

In the various figures of the drawing, like parts are always provided with the same reference numerals. The description applies to all drawing figures in which the corresponding part can also be recognized.

1 shows a schematic representation of the residual current circuit breaker according to the invention 1 with the summation current transformer according to the invention mounted therein 10 in a top view. The residual current circuit breaker 1 has a housing 2 in which the individual components of the residual current circuit breaker 1 are held and protected. In the case 2 are four terminals 5 (two input terminals 5 and two output terminals 5 ) for contacting the residual current circuit breaker 1 arranged with electrical connection conductors of an external line circuit (not shown). In the case 2 of the residual current circuit breaker 1 are two primary conductors 3 arranged, which are formed as strands and over their ends 4 one each of the input terminals 5 with one of these associated output terminal 5 connect electrically conductive. To detect fault currents, the primary conductors 3 by a summation current transformer 10 guided. This has a ring or tubular magnetic core 11 (please refer 3A . 3B . 5B such as 6 ) with an opening 13 on. The magnetic core 11 is with a thin secondary conductor 12 wrapped. The secondary conductor 12 can be designed for reasons of space as enamel wire secondary conductor. The winding is not in the circumferential direction, but substantially along a longitudinal direction A of the annular or tubular magnetic core 11 , ie along the generatrices of the magnetic core 11 , executed. The secondary conductor windings 12 are evenly over the entire circumference of the magnetic core 11 distributed to the best possible symmetry resistance and thus an improved tripping accuracy of the summation current transformer 10 to achieve and avoid false tripping as far as possible.

Because when performing the primary conductor 3 through the opening 13 of the magnetic core 11 the sensitive secondary conductor windings 12 could be easily damaged, the summation current transformer 10 a substantially hollow cylindrical partition 20 on which in the opening 13 of the magnetic core 11 is plugged. In this way, when performing the primary conductor 3 through the opening 13 of the magnetic core 11 the stripped and thus sharp-edged ends 4 the primary conductor strands 3 not in direct contact with the sensitive secondary conductor windings 12 come. The secondary conductor windings 12 thus be through the bulkhead 20 from damage when passing through the primary conductors 3 effectively protected.

Since the partition only in an inner region, ie in the region of the opening 13 of the magnetic core 11 is arranged, but not on the outer circumferential surface of the cylindrical summation current transformer 10 , the limited space available inside the housing 2 for a correspondingly larger dimensions of the magnetic core 11 be used. The tripping accuracy of the summation current transformer 10 and thus the residual current circuit breaker 1 is thereby significantly improved.

In the 2A and 2 B is the barrier 20 the summation current transformer according to the invention 10 perspective shown schematically in two views. The barrier 20 has a substantially cylindrical body 21 on, which extends in a longitudinal direction A. At a first end 22 of the cylindrical body 21 is a collar 24 formed, which in a radial direction R of the cylindrical base body 21 protrudes outwards and a first end face 14 of the summation current transformer 10 at least partially covering. At a second end 23 which is the first end 22 is arranged opposite, has the cylindrical body 21 several extensions 25 on, which parallel to the longitudinal direction A to the cylindrical body 21 are formed. These extensions or tabs 25 can after the installation of the partition 20 at the summation current transformer 10 in the radial direction R are bent outwards, on the one hand, the partition 20 in its installation position within the opening 13 of the summation current transformer 10 to fix, and on the other hand, the second end face 15 of the summation current transformer 10 at least partially cover and thus protect against damage.

The 3A to 3C schematically show several steps in the assembly of the summation current transformer according to the invention 10 , 3a shows the magnetic core 11 which is provided with a plurality of secondary conductor windings 12 is uniformly wound in a substantially axial direction over the entire circumference of the toroid. In the inner area, that is, in the area of the opening 13 of the summation current transformer 10 , is a barrier 20 arranged, whose tab-like extensions 25 from the ring torus of the summation current transformer 10 protrude. 3b shows a subsequent assembly step, in which the tab-like extensions 25 the partition 20 in the area of a second end face 15 of the summation current transformer 10 are bent in the radial direction R to the outside. The extensions 25 thus stick the area of the second end face 15 of the summation current transformer 10 in the area of the opening 13 at least partially off.

3c shows the summation current transformer according to the invention 10 with those through the opening 13 guided primary conductors 3 , The primary conductor strands 3 are each twice through the opening 13 of the summation current transformer 10 passed through to the tripping accuracy of the residual current circuit breaker 1 to improve. For this purpose, the primary conductor strands 3 outside on the magnetic core 11 of the summation current transformer 10 recycled. However, this space is sufficient, so that a threat to the outer secondary conductor strands 12 through the stripped, sharp-edged ends 4 the primary conductor strands 3 can be avoided. The barrier 20 thus seals the secondary conductor 12 only in an inner area 13 as well as in the area of the first front side 14 and the second end face 15 of the summation current transformer 10 against the primary conductor strands 3 from. Damage to the sensitive secondary conductor turns 12 can thus be effectively prevented in the above areas.

In the 4A to 4D are alternative embodiments of the partition 20 shown schematically. The in the 4A to 4C illustrated alternative embodiments have within the partition 20 each a guide element 26 for clear guidance and positioning of the barrier 20 guided primary conductor strands 3 on. This guide element 26 For example, as a rib ( 4C ) or as a guide cross ( 4B ) be formed. 4D shows a further embodiment of the partition 20 : here is the partition 20 of two substantially identical bulkhead halves 27 and 28 composed, which at their contact line by means of a snap toothing 29 connected to each other. The two bulkhead halves 27 and 28 are initially separated from two different sides in the wound magnetic core 11 introduced and only within the magnetic core 11 by compressing in the longitudinal direction A over the snap teeth 29 together. This embodiment has the advantage that the partition 20 in the longitudinal direction A and at the second end a complete collar 24 instead of the several bendable tabs 25 comprising the sensitive secondary conductor 12 also in the area of the second end face 15 of the summation current transformer 10 from damage due to the sharp-edged ends 4 the primary conductor strands 3 protects.

The 5A and 5B show schematic representations of an alternative embodiment of the summation current transformer according to the invention 10 and the thus equipped, inventive residual current circuit breaker 1 , Instead of in the area of the first front page 14 trained collar 24 has the bulkhead 20 a mounting plate 30 on which in the housing 2 of the residual current circuit breaker 1 through several guide ribs 6 is guided and supported. In this way, the summation current transformer 10 not just by the primary conductor strands 3 , but also on the mounting plate 30 the partition 20 in a precisely defined position within the housing 2 of the residual current circuit breaker 1 fixed.

In 6 is a size comparison of the summation current transformer according to the invention 12 (in 6 left) compared to a summation current transformer with conventional isolation 50 (in 6 right) shown schematically. The conventional containment 50 has two concentrically arranged cylinders 51 and 52 on, which at their end faces, each with an annular lid 53 are closable and the with the secondary conductor 12 wound magnetic core 11 completely absorb and thus the entire surface of the wound magnetic core 11 protect. However, this complete protection leads to an increased space requirement within the housing 2 of the residual current circuit breaker 1 , Because the partition 20 the summation current transformer according to the invention 10 only in an inner area of the magnetic core 11 as well as partly in the area of the first front side 14 and the second end face 15 is arranged, but not in the region of the outer circumferential surface of the wound magnetic core 11 , The summation current transformer according to the invention 10 be kept compact by up to 25%. This is especially for use in residual current circuit breakers 1 with a narrow housing of only two graduation units of great advantage. Alternatively, the magnetic core 11 by omitting the partition in the region of the outer surface of the wound magnetic core 11 be sized larger, which is advantageous to the tripping accuracy of the summation current transformer 10 and thus the residual current circuit breaker 1 effect.

LIST OF REFERENCE NUMBERS

1

Residual Current Device

2

casing

3

Primary conductor / primary conductor strand

4

The End

5

terminal

6

guide rib

10

Summation current transformer

11

magnetic core

12

Secondary conductor / secondary conductor winding

13

inner area / opening

14

first end face

15

second end face

20

compartmentalization

21

Cylinder wall / basic body

22

first end

23

second end

24

collar

25

Extensions / tabs

26

guide element

27

first part / first half

28

second part / second half

29

snap teeth

30

mounting plate

50

conventional containment

51

inner cylinder

52

outer cylinder

53

cover

A

Longitudinal extension

R

radial direction

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102005007334 A1 [0006]

Claims (11)

Summation current transformer ( 10 ) for a residual current device ( 1 ), for detecting alternating current sensitive and / or pulse current sensitive fault currents in a line circuit, - with a cylindrical magnetic core ( 11 ), which is connected to a secondary conductor ( 12 ), - in which the magnetic core ( 11 ) an inner area ( 13 ), which is used to pass through a plurality of primary conductors ( 3 ) of the circuit, - with a partition ( 20 ), which the secondary conductor ( 12 ) from damage during the passage of the primary conductors ( 3 ) in the inner area ( 13 ) of the magnetic core ( 11 ), characterized in that the partition ( 20 ) is substantially cylindrical and only one cylinder wall ( 21 ), wherein the cylinder wall ( 21 ) in the inner area ( 13 ) of the magnetic core ( 11 ) is arranged. Summation current transformer ( 10 ) according to claim 1, characterized in that the partition ( 20 ) at a first end ( 22 ) an axial longitudinal direction (A) of the cylindrical bulkhead ( 20 ) a collar ( 24 ), which has a first end face ( 14 ) of the annular or tubular magnetic core ( 11 ) at least partially covers. Summation current transformer ( 10 ) according to one of the preceding claims, characterized in that the partition ( 20 ) at a second end ( 23 ) its axial longitudinal direction (A) several extensions ( 25 ), which after insertion of the partition ( 20 ) in the annular or tubular magnetic core ( 11 ) are bendable outwards in a radial direction (R). Summation current transformer ( 10 ) according to one of the preceding claims, characterized in that the partition ( 20 ) in an inner region of its cylindrical body ( 21 ) at least one guiding element ( 26 ) for guiding the primary conductors ( 3 ) having. Summation current transformer ( 10 ) according to one of the preceding claims, characterized in that the secondary conductor ( 12 ) evenly distributed over an entire surface of the annular or tubular magnetic core ( 11 ) is wound. Summation current transformer ( 10 ) according to one of the preceding claims, characterized in that the secondary conductor ( 12 ) is designed as enamel wire secondary conductor. Summation current transformer ( 10 ) according to one of the preceding claims, characterized in that the partition ( 20 ) is formed in two or more parts. Summation current transformer ( 10 ) according to claim 7, characterized in that the two parts ( 27 . 28 ) of the containment ( 20 ) in the region of the cylinder wall ( 21 ) are plugged together. Residual current circuit breaker ( 1 ) for detecting alternating current sensitive and / or pulse current sensitive fault currents in a line circuit, wherein the residual current circuit breaker ( 1 ) a summation current transformer ( 10 ) according to one of claims 1 to 8. Residual current circuit breaker ( 1 ) according to claim 9, characterized in that the primary conductors ( 3 ) of the line circuit are formed as flexible strands, which by the magnetic core ( 11 ) of the summation current transformer ( 10 ) are guided. Residual current circuit breaker ( 1 ) according to one of claims 9 or 10, characterized in that the primary conductors ( 3 ) already before passing through the magnetic core ( 11 ) stripped ends ( 4 ) exhibit.

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