DE102009026742A1 - Current transformer unit - Google Patents

Abstract

The current transformer assembly has three current transformers (1,2,3) for detecting current flowing through the fuse block. Each of the current transformer has primary conductors (10,12) circumferentially surrounding the core. The coil shaped core surrounds the core secondary conductor. The ends of the secondary conductor have a measuring port, and the primary conductor is connected to output connection of the fuse panel with a connecting cable. An independent claim is also included for a fuse panel.

Description

The The present invention relates to a power conversion unit for a fuse load bar and a fuse load bar with a such a current transformer unit.

Fuse switches, mostly low-voltage, high-performance (NH) fuse switch-disconnectors, have long been known and serve safe electric To provide outgoing busbars that are under load can be separated. The facilities generally have one or more fuse bases, each with two fuse holders have and are arranged in a housing. Appropriate Fuse links are on one or more switch covers mounted so that with a closed switch cover the fuse links are inserted in the fuse bases and a connection between the respective supply contacts that can be connected to the busbars and make the outgoing contacts. When opening the or the switch cover are the fuse links from the Pulled fuse chases so that the connection is broken is.

Often is a measurement of the current flow over the provided Departure desired. For this purpose, current transformers are usually used. Current transformers work like transformers, d. H. one by one Primary conductor, in the prior art usually the electrical Connection between busbar connection and a first Fuse or the electrical connection between a second fuse holder and the outgoing terminal of the Ledge, flowing alternating current induced in one of Current transformers provided secondary conductors one of the Primary circuit galvanically isolated secondary current, measured and evaluated to determine the primary current can be. Thus, the measurement of the current flow over The contact provided by the fuse load bar without contact. The current transformer is the connecting line between the Busbar connection and a first fuse holder or a second fuse receptacle and an outgoing terminal arranged.

It For example, so-called plug-on current transformers are known which have a core and a surrounding secondary conductor. Of the Core is pushed over a current-carrying line and is electrically isolated from this. The alternating current flow through the line induces an alternating magnetic field in the core, which in turn has a current flow in which the core is coil-shaped induced secondary conductor. Such Aufsteckstromwandler However, in the typical sizes, they have thicknesses, which apply significantly and in the rule lead to that the fuse switch-disconnectors in a control cabinet build higher as the same bars without current transformers.

About that In addition, the assembly of plug-in current transformers to existing, already installed fuse load switch strips consuming, there for mounting the fuse switch disconnector must be removed from the control cabinet got to.

For example, in the DE 100 02 800 A1 an embodiment of a NH fuse-switch-disconnector is shown in which, if necessary, a current transformer can be threaded with a slot-shaped opening on the Z-shaped feed contact between the electrical busbar terminal and a first fuse holder. In order to enable such threading, however, the housing bottom must be designed to be open, which leads to considerable constructive measures on the housing. In addition, a corresponding contact protection can hardly be guaranteed.

In contrast, It is an object of the present invention, a current transformer unit provide, which subsequently, d. H. then, when the fuse load bar already installed in a control cabinet is, can be installed.

About that In addition, it is an object of the present invention, a current transformer unit which is designed to be compatible with a conventional, commercially available fuse load bar is connectable, without that the fuse load bar for a special design would have to have.

At least One of the aforementioned objects is achieved by a current transformer unit for a fuse load bar with three current transformers for Detection of a current flowing through the fuse load bar each of the current transformers having one primary conductor each, a ring surrounding the primary conductor core and a coil surrounding the core secondary conductor has, wherein the ends of the secondary conductor depending one Measuring terminal, and wherein the primary conductor a first connectable to a feeder terminal of the fuse load bar End and a second connectable with a connecting cable end having.

The current transformer unit according to the invention can be mounted on a commercial fuse load bar without having to remove these from the cabinet. For this purpose, the current transformer unit can be connected to the outgoing connections of the fuse load bar. The fuse load bar does not have to have any special design features for accommodating the current transformer element according to the invention at its outgoing area which deviate from the commercial ones.

About that In addition, it allows the invention Current transformer unit due to their arrangement in the outgoing area of the fuse load bar or by extending this area, one and the same Strip with all known connection techniques, d. H. especially Frame clamp, bolt and nut to provide.

The Integration of the three current transformers in a single current transformer unit simplifies the assembly considerably, because instead of three separate transducers only to assemble a single compact unit.

The Arrangement of the converter unit in the outgoing area of a fuse load bar provides more volume for the current transformers as with conventional between fuse load bar and busbar arranged current transformers is the case. Therefore can with the current transformer unit according to the invention larger power ranges of the fuse load bars be covered than is conventionally the case. In One embodiment of the invention is each of the three Current transformer designed or dimensioned so that he a power flowing through its primary conductor of more than 5 VA is suitable.

in principle The current transformer unit can also be used with open distribution strips be used, in which the fuse links with pulled a suitable tool from the open housing can be. The term fuse load bar should therefore both fuse switch disconnectors and open distribution strips include.

at the current transformer unit according to the invention the primary conductor unlike plug-in current transformers the prior art component of each current transformer and is connected to the outgoing terminal of the fuse load bar. In this sense, extends the primary conductor of the invention Current transformer unit the outgoing terminal of a fuse load bar. Therefore, the second ends are the primary conductors of the power conversion unit designed so that they can be connected with a connecting cable are.

In In one embodiment, the primary conductor is as Ladder plate executed.

requirement for the realization of an inventive Current transformer unit is that these at least in one embodiment a building measure whose width and height the Dimensions of the outlet area of a conventional safety edge does not exceed.

there it is expedient if two of the primary conductors arranged in a plane while the third primary conductor has a distance to this plane. That way you can the primary conductors with the outgoing terminals one connect commercially available fuse load bar, which usually a corresponding geometric arrangement of the outlet connections exhibit. The relocation of a primary conductor from the Level out from the other two primary ladders is clamped, allows a minimization of the width the current transformer unit.

In In a preferred embodiment, the cores of the three Current transformer arranged so that at least two of the cores in one Direction parallel to the primary conductors have no spatial overlap.

A staggered arrangement of at least one core relative to the two other cores in a direction substantially parallel to the primary ladders allows the height to minimize the current transformer unit. In one embodiment the three primary conductors are substantially parallel to each other arranged.

In According to one embodiment, the primary conductor its first end a through hole for screwing the primary conductor with an output terminal on a fuse load bar. A screwing of the primary conductor with the outlet connection ensured a good electrical connection between the current transformer unit and the fuse load bar.

In an embodiment of the current transformer unit, the second end of the primary conductor has a through hole for screwing of the primary conductor with a cable lug of a connecting cable exhibit. It is expedient if the primary conductor in Area of the through hole a thread for receiving a through the Lug has cross-thread screw or a nut is connected to the primary conductor so that they are has concentric internal thread to the through hole.

In an alternative embodiment has the second end of the primary conductor a clamping structure for receiving a Connection cable on. In this case, the clamping structure is preferably designed so that in him a cable end of a connecting cable record and the cable with the help of the terminal structure is pressed against an electrically conductive portion to a electrical connection between the connecting cable and the Making primary conductor.

In a preferred embodiment each However, the current transformer unit comprises a housing, wherein in the housing a the primary conductor associated recess is provided into which a push insert is inserted, wherein the push insert has a recess for receiving a connection element.

A Such an embodiment of the current transformer unit with a, preferably However, three drawer elements or sliding inserts for Recording a connection element allows a rapid adaptation of the second, the outgoing connections forming Ends of the current transformer unit. Such an adjustment can also done during assembly on a construction site. As soon as determines how the power conversion unit connected to the outgoing cable should be the push insert with a corresponding connection element equipped and in the housing of the current transformer unit be inserted.

there the push insert and the recess of the housing are preferably designed such that a arranged in the recess of the drawer insert Connecting element after inserting the push insert in the corresponding recess of the housing an electrical Contact to the respective primary conductor of the current transformer unit having.

In In one embodiment, the connection element is which is receivable in the recess of the push insert, a Terminal construction. In an alternative embodiment the connecting element is a nut, which is a screw provides for screwing a pole piece with the primary conductor.

In In one embodiment, the push insert and / or the Recess in the housing of the current transformer unit a movable or deformable locking element, and the recess in the housing the current transformer unit and / or the push insert has a recess for receiving the locking element. In this way increases the mechanical stability of the drawer assembly connected to the primary conductor connecting element.

At least One of the aforementioned tasks is also performed by a backup load bar solved with a current transformer element described above.

there is the fuse load bar in a preferred embodiment a fuse load switch strip, which is a housing lower part, in the three electrical busbar terminals, each with connected to a first fuse holder, and three output terminals, each connected to a second fuse holder, are arranged, an upper housing part and one opposite the housing top arranged verschränkbar Has shift lid, the at least one holding device for having a fuse link, wherein in each case a primary conductor the current transformer unit with an outgoing terminal of the fuse load switching strip connected is.

Further Advantages, features and applications of the present The invention will be apparent from the following description of an embodiment and the associated figures clearly.

1 shows a three-dimensional view of an embodiment of the current transformer unit according to the invention seen from the second end of the primary conductor.

2 shows a three-dimensional representation of the current transformer unit 1 seen in a view from the first end of the primary conductor.

3 shows a partial sectional view of the current transformer unit 1 and 2 in a plane which intersects the upper transducer.

4 shows a partial sectional view through the current transformer according to 1 to 3 in a sectional plane through the two lower transducers.

5 shows a partial sectional view through the current transformer unit according to 1 to 5 in a plane parallel to the primary ladders.

5 shows an exploded view of the current transformer unit according to 1 to 6 ,

The in the 1 to 7 illustrated embodiment of a current transformer unit according to the invention for a fuse load bar has an arrangement of three current transformers 1 . 2 . 3 on, the compact in a multi-part housing 4 . 5 . 6 are arranged.

The construction of each current transformer of the current transformer unit is particularly well in the sectional view 5 to recognize. The sectional view 5 represents a section through the current transformer unit in a plane perpendicular to that of the primary conductors 10 . 11 . 12 the converter 1 . 2 . 3 clamped levels and stands by the clamping screw 15 of the clamping structure 9 of the upper converter 3 runs.

The converter 3 has a primary conductor designed as a conductor plate 12 on which the extension of the outgoing terminal of a fuse load switch bar (not shown) is used. To the flow of current through the primary conductor 12 to be able to detect, has the current transformer 3 over a metallic core 18 which is configured as a ring and the primary conductor 12 surrounds. The core 18 turn is from a secondary conductor 19 surrounded, the ends of each with a measuring terminal 22 . 23 are connected. The measuring connections 22 . 23 can be contacted from the outside with the aid of test probes to that in the secondary conductor 19 to detect induced measuring current.

The primary conductor 12 that surrounds him annular annular core 18 as well as the secondary conductor 19 together form a transformer which has only half a winding on the primary side, that of the through the core 18 extending primary conductor 12 is formed.

The two other intended for the other two outgoing terminals of a switching strip converter 1 . 2 have an identical structure to the converter 3 on. They also each have a primary conductor 10 . 11 , a core 16 . 17 as well as a secondary conductor 20 . 21 ,

How particularly clear from the three-dimensional view 2 indicates the primary conductors 10 . 11 . 12 the current transformer 1 . 2 . 3 at their first end in each case a perforation 24 . 25 . 26 on. With the help of these through holes and screws engaging in the through holes, the current transformer unit is electrically and mechanically connected to the outgoing terminals of a fuse load switch bar.

At their opposite ends, the three primary conductors 10 . 11 and 12 each a terminal structure 7 . 8th . 9 for connecting the primary conductors 10 . 11 . 12 with cables as outputs of the fuse load switching strip. The concrete structure of the clamping assemblies 7 . 8th . 9 is especially good the 1 . 6 and 7 refer to.

The detailed construction of the clamping structure 7 will now be based on the 6 described. The two other terminal assemblies 8th and 9 are identical.

The clamp construction 7 has a substantially U-shaped cage bracket 27 on, the two leg sections 28 . 29 and one leg portions 28 . 29 connecting floor section 30 having. Furthermore, a cage yoke 31 provided, which is substantially at the bottom of the section 30 opposite side of the leg sections 28 . 29 connecting them together so that between the cage yoke 31 on the one hand and the cage bracket 27 on the other hand, a space is formed, which is also referred to below as a cage cell. In the cage cell is between the two leg sections 28 . 29 a clamping piece 32 arranged. This clamp 32 divides the cage cell into a terminal space for the primary conductor 11 and a cable room for receiving the cable. The connection space is essentially limited by the clamping piece 32 and the bottom section 30 while the cable space from the clamping piece 32 , the two leg sections 28 . 29 and the cage yoke 31 is limited. The cage yoke 31 has a threaded through bore through which a grub screw 14 with a clamping plate 33 , which is arranged in the cable compartment, is connected. By turning the threaded pin 14 can the clamp 33 in the direction of the clamping piece 32 or be moved away from it. The two leg sections 28 . 29 have at their the bottom section 30 opposite end two cranked sections 34 . 35 on. These beheaded sections 34 . 35 are formed such that the distance between them is slightly smaller than the corresponding extent of the cage yoke 31 , so in the example in 1 shown position the cage yoke 31 not up from the cage frame 27 can be removed without the two legs are bent outwards. Furthermore, both legs have 28 . 29 an approximately U-shaped recess having a corresponding tongue portion 36 surrounds. This tongue section 36 has been bent in the production of something in the direction of the cage cell, so that in the example in 1 shown position the cage yoke 31 on both sides of the corresponding tongue section 36 supported. For removal of the cage yoke 31 must either the leg sections 28 . 29 be slightly bent apart or the cage yoke 31 must be pushed forwards (or backwards).

It can be clearly seen in particular in the 1 and 6 in that each of the clamping assemblies 7 . 8th . 9 with the help of a push insert 37 . 38 . 39 on the housing 4 the transducer device is attached. All push inserts 37 . 38 . 39 are configured identically, so that the specific embodiment is now referring to 6 based on the push insert 37 is described.

The push insert 37 has a recess 40 on, in which the bottom section 30 of the clamping structure 27 can be used. The recess 40 is from side cheeks 41 . 42 and a front stop surface 43 limited. Furthermore, the push insert on two locking elements (not shown in the figures), which are elastically deformable.

Alternatively to the recording of the clamping structure shown in the figures 27 can the push insert 38 a nut (not shown), which allows a pole piece with the primary conductors 10 . 11 . 12 to screw. This is indicated by the push insert 38 a recess 44 to the Auf take a nut on.

From a synopsis of 4 and 5 , which have substantially the same scale, it becomes clear how the inventive arrangement of the individual current transformers 1 . 2 . 3 a compact design of the current transformer unit with the three current transformers 1 . 2 . 3 allows. The converter unit has a comparatively small width and height. These are the two current transformers 1 . 2 leading to the two primary conductors 10 . 11 belong, arranged at the same height, ie the centers of their annular cores lie in the plane in which also the primary conductors 10 . 11 lie. In contrast, the third transducer is arranged in a different plane, both its primary conductor 12 , its core 18 as well as his secondary leader 19 are above the other two current transformers 1 . 2 , This arrangement of the transducers one above another allows a small width of the current transformer unit according to the invention, so that it can be accommodated in the outgoing area of a conventional fuse load switching strip.

In addition, the third current transformer 3 in the viewing direction for example of 1 behind the other two current transformers 1 . 2 arranged. Ie. the cores 16 and 18 respectively. 17 and 18 the current transformer 1 and 3 respectively. 2 and 3 overlap one another in a direction parallel to the primary conductors 10 . 11 . 12 not spatially. In this way, a much tighter pack of Stormwandler 1 . 2 and 3 be reached, ie the primary conductor 10 and 12 respectively. 11 and 12 have a much smaller distance from each other than would be the case if the third transducer 3 immediately above the two transducers 1 and 2 would be arranged.

1, 2, 3

Power converter

4

first housing part

5

second housing part

6

third housing part

7, 8, 9

terminal building

10 11, 12

primary conductor

13 14, 15

Set screw

16 17, 18

metallic core

19 20, 21

secondary conductor

22 23

measuring connection

24 25, 26

perforation

27

roll cage

28 29

leg portion

30

bottom section

31

Käfigjoch

32

clamp

33

clamp

34 35

cranked section

36

tongue portion

37, 38, 39

railable

40

recess

41 42

lateral cheek

43

front stop surface

44

recess for receiving a nut

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10002800 A1 [0006]

Claims (14)

Current transformer unit for a fuse load bar with three current transformers ( 1 . 2 . 3 ) for detecting a current flowing through the fuse load bar, each of the current transformers ( 1 . 2 . 3 ) one primary conductor each ( 10 . 11 . 12 ), a primary conductor ( 10 . 11 . 12 ) annularly surrounding core ( 16 . 17 . 18 ) and a coil surrounding the core secondary conductor ( 19 . 20 . 21 ), wherein the ends of the secondary conductor ( 19 . 20 . 21 ) each a measuring connection ( 22 . 23 ), and wherein the primary conductor ( 10 . 11 . 12 ) has a first connectable to an outgoing terminal of the fuse load bar end and a second connectable to a connecting cable end. Current transformer unit according to claim 1, characterized in that two of the primary conductors ( 10 . 11 ) are arranged in one plane, while the third primary conductor ( 12 ) has a distance to this plane. Current transformer unit according to claim 1 or 2, characterized in that the cores ( 16 . 17 . 18 ) of the three current transformers ( 1 . 2 . 3 ) are arranged so that at least two cores ( 16 . 18 respectively. 17 . 18 ) in a direction parallel to the primary conductors ( 10 . 11 . 12 ) have no spatial overlap. Current transformer unit according to one of claims 1 to 3, characterized in that the primary conductor ( 10 . 11 . 12 ) is designed as a conductor plate. Current transformer unit according to one of claims 1 to 4, characterized in that the primary conductor ( 10 . 11 . 12 ) at its first end a perforation ( 24 . 25 . 26 ) for screwing the primary conductor ( 10 . 11 . 12 ) having an outgoing terminal of a fuse load bar. Current transformer unit according to one of claims 1 to 5, characterized in that the primary conductor ( 10 . 11 . 12 ) at its second end a perforation ( 24 . 25 . 26 ) for screwing the primary conductor ( 10 . 11 . 12 ) with a cable lug of a connecting cable. Current transformer unit according to one of claims 1 to 6, characterized in that the primary conductor ( 10 . 11 . 12 ) at its second end a clamping structure ( 7 . 8th . 9 ) for receiving a connecting cable. Current transformer unit according to one of claims 1 to 7, characterized in that the current transformer unit comprises a housing ( 4 . 5 . 6 ), wherein in the housing ( 4 . 5 . 6 ) a primary conductor ( 10 . 11 . 12 ) associated recess ( 40 ), into which a push insert ( 37 . 38 . 39 ) is insertable, wherein the push insert ( 37 . 38 . 39 ) a recess ( 40 ) for receiving a connection element. Current transformer unit according to claim 8, characterized in that the push insert ( 37 . 38 . 39 ) and / or the recess ( 40 ) in the housing ( 4 . 5 . 6 ) of the current transformer unit has a movable or deformable latching element, and the recess ( 40 ) in the housing ( 4 . 5 . 6 ) of the current transformer unit and / or the push insert ( 37 . 38 . 39 ) has a recess for receiving the locking element. Current transformer unit according to claim 8 or 9, characterized in that the connection element has a clamping structure ( 7 . 8th . 9 ). Current transformer unit according to claim 8 or 9, characterized characterized in that the connecting element is a nut. Current transformer unit according to one of the claims 1 to 11, characterized in that each of the three current transformers designed to be for one by its primary leader flowing power of more than 5 VA is suitable. Fuse load bar with a current transformer element according to one of claims 1 to 12. Fuse load bar according to claim 13, characterized in that it is a fuse load switch bar, which a housing lower part, in which three electrical busbar terminals, which are respectively connected to a first fuse holder, and three outgoing terminals, which are each connected to a second fuse holder, are arranged Has housing upper part and a relative to the upper housing part pivotally mounted switch cover having at least one holding device for a fuse link, wherein in each case a primary conductor ( 10 . 11 . 12 ) of the power conversion unit is connected to an outgoing terminal of the fuse load switching strip.