AU8453482A - Distribution board for electrical installations - Google Patents

Description

Distribution board for electrical installations

The present invention relates to a distribution board for electrical installations in which an incoming three phase system is to be distributed between single- phase and three-phase conductor race ways.

There are previously known distribution boards for electrical installations in which the incoming three- phase system is branched out or distributed via fuse elements or automatic fuses to appropriate single-phase and three-phase conductor race ways. Such distribution boards are today mounted on the site of the installation where the electrician must put together each individual element or automatic fuse and also connect the current supply to the bottom screw of the element or automatic fuse, respectively. When distributing, the individual conduit race ways or conduit runs the electrician must watch- that the incoming phases are loaded as evenly as possible.

The object of the present invention is to provide a distribution board for electrical installations which does not suffer from the disadvantage involving an uneven loading of the phases R, S and T taking place during the installation. Another object of the present invention is to provide a distribution board which makes the bottom connection to each fuse element or automatic fuse superfluous, for thereby reducing the possibility of poor contact and thereby the risk of heat development in the element to a minimum. Yet another object o the invention is to provide a distribution board having physical dimensions which are less than those of known boards constructed from hitherto known elements.

These objects are achieved in connection with a distribution board of the type stated in the preamble, which according to the invention is characterized in that it comprises a preconnected bus system which

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^Zn- distributes the three incoming phases R, S and T in rows and columns of race way connection points, so that the phases R, S and T are alternated sequentially both along the rows and the columns of the connection points.

By means of such a distribution board or board module the electrician can during the electrical in¬ stallation in a bungalow or a larger building refrain from dividing the installation between the phases R, S and T as this division is already effected by means of the bus system included in the board module.

Besides, the bottom of the fuse elements are preconnected to the above-mentioned bus system, and it is thereby possible to avoid the dangers associated with heat development coming about in known distribution boards in which unsafe connections at the bottom of the elements can exist. In the present distribution board there is between the bus system and the bottom of the elements only one connection for each phase, irrespec¬ tive of how many elements are included in each board module.

Preferably the distribution board comprises at least three rows of conductor race way connection points, each column comprising three connection points and each connection point associated with one of the phases being connected by means of buses running iri zigzag.

In a preferred embodiment the distribution board according to the invention comprises a bottom plate of electrical insulating material carrying the bus system for distribution of the conductor race way connection points, as well as a connection plate arranged above the bus system and consisting of electrical insulating material carrying fuse element holders having connection points for the conductor runs, as well as a top cover covering the charged parts of the fuse element holders .

OMPI The invention will in the following be further described, reference being had to the drawing, which illustrates an embodiment of the distribution board according to the invention.

On the drawing there is illustrated an exploded isometric view of an embodiment of a distribution board according to the invention, Fig.1a illustrating a bottom plate carrying zig¬ zag-shaped bus systems,

Fig. lb illustrating a connection plate of elec¬ trical insulating material carrying fuse element holders with connection points for the conductor runs,

Fig. lσ illustrating a cover for screening off the charged points of the plate according to Fig. lb and allowing access to the portions of the elements holding the fuses, and

Fig. Id illustrating fuse caps serving to retain the fuses in the fuse elements of Fig. lb.

On the drawing there appears an embodiment of the distribution board for electrical installations according to the invention, a bottom plate 1 of electrical insu¬ lating material being depicted in Fig. la. On the bottom plate 1 there are provided three main connection clamps, 2R, 2S and 2T, respectively, which are connected to a not illustrated incoming three-phase system symbo¬ lized by the designations R, S and T.

Connection straps 3R, 3S and 3T, respectively, extend from the clamps 2R, 2S and 2T, and are at the ends opposite the clamps supported by guiding studs of different heights. Thus, the strap 3R is supported by a m* stud 4R of relatively small height, whereas the strap 3S

^? is supported by a guiding stud 4S of medium height and the strap 32 is supported by a guiding stud 4T, which is higher than the previously mentioned studs . The reason for giving the studs 4R, 4S and 4T different heights, is that the respective straps 3R, 3S and 3T are connected to their own zigzag-shaped bus system 5R, 5S and 5T, respectively, which at a certain distance are crossing each other, the bus system 5R being supported on a plurality of guiding studs 4RR having a height corre¬ sponding to that of the guiding stud 4R, the bus system 5S being supported on guiding studs 4SS having heights corresponding to the guiding studs 4S, and the bus system 5T being supported on high studs 4 T correspon¬ ding to the studs 4T. The above-mentioned bus systems 5R, 5S and 5T are so designed that when being connected to the straps 3R, 3S and 3T, they distribute the three incoming phases R, S and T in rows RO and columns CO of conductor race way connection points so that the phases R, S and T are alternated sequentially both along the rows RO and the columns CO of connection points. Between every stud in the respective bus system and the buses themselves there is mounted a bimetallic disc 6 serving to provide a temperature dependent pressure against the buses 5R, 5S, 5T from the respective guiding studs 4RR, 4SS, 4TT. In the area of the guiding studs there are on the buses 5R, 5S, 5T provided sleeve-shaped contact studs 7R, 7S, 7T, in which there is provided a threaded portion into which the bottom screw of a fuse element can be screwed. The contact lugs 7R, 7S and 7T are of different, heights, dependent on which phase they represent, the contact lug 7R having a greatest height, the contact lug 7S an intermediate height and the contact lug 7T a smallest height for thereby together with the respective subjacent guiding lugs 4RR, 4SS and 4TT, respectively, having their top surfaces at the same level above the bottom plate 1. upon assembly of the zigzag-shaped buses 5R, 5S and 5T the latter will run at different height, but the connection points represented by the sleeve-shaped contact lugs 7R, 7S and 7T will be at the same height above the bottom plate 1.

Above the bus system there is mounted an element plate 13, for example of the type illustrated in Fig. 1, onto which there are mounted fuse holders 14 having an upper threaded portion 15 with connection clamps 16. The fuse holders 14 can either be firmly molded to the element plate 13 or be attached to said plate by other attachment means, for example screw connection or similar. The element plate 13 is screw connected to the subjacent bottom plate 1, the element plate 13 being assembled on appropriate mounting bolts 17 arranged at the corners of the bottom plate 1 and having a top portion 18 which is adapted to corresponding recesses 19 in the element plate 13 , so that the element plate 13 can be threaded onto the top portions 18 and screw connected to the bottom plate 1, for example by not illustrated screws fitting into the threaded portion 20 of the top portion 18 of the mounting bolt 17.

Appropriately, there are on the bottom side of the element plate 13 provided a plurality of supporting studs 21 serving to press against the zigzag-shaped bus systems 5R, 5S and 5T, so that these are held down on the guiding studs 4R, 4S and 4T with a suitable pressure.

Above the element plate 13 there is mounted a cover plate 22, for example of the type illustrated in Fig. lc, the purpose of the cover plate being to protect against touching of the charged parts, namely the connection clamps 16 on the fuse holders 14 on the element plate 13. In the cover plate 22 there are provided a series of holes 23 which as regards their positions, correspond to the positions of the fuse holders 14 on the element plate 13 , for thereby allowing an access to the fuse holders 14 , which is protected against any touch with the charged parts when the cover plate 22 is put in position on the element plate 13.

After the assembly of the bottom plate 1 and element plate 13 into a module, the latter can be mounted in an appropriate fuse board for connection to the individual conductor runs, said conductor runs being connected to the connection clamps 16 on the fuse holders 14 of the element plate 13. After the com¬ pletion of the connection of the conductor runs, the cover plate 22 can be put in position, whereafter the elements illustrated in Fig. Id, namely the bottom screw 24, the fuse 25 and the fuse cover 26, can be put in position in their respective fuse holders 14 for making the assembled distribution board ready for use.

Because the bus systems 5R, 5S and 5T pass along in a zigzag pattern as illustrated in Fig. 1, it is possible upon the connection of outgoing conductor runs to choose between one-phase and three-phase race ways, either by using connection points in horizontal direction or in vertical direction, i.e. by going along either the rows RO or the columns CO. If a choice is made to use the two first elements in the horizontal direction for a one-phase conductor race way it is possible, as a matter of course, to use the three following elements for a three-phase conductor race way or vice versa. In other words, in connection with the bus system according to the invention, the advantage is at hand that the phases R, S and T always will be present in the correct sequence in horizontal and vertical direction, so that the electrician does not have to think of which phase the element is connected to. In other words the electrician does not have to connect each individual element in the bottom connection because the distribution board module has only one connection for each phase, irrespective of the number of elements in each module. Due to a smaller number of connections per phase, the risk of poor contact and thereby the risk of heat development in the element is avoided.

It will further appear that if the three first elements in the vertical direction is used as a three phase race way, the next three elements in horizontal direction can be used for a second three-phase conductor race way. This means that elements for the outgoing conductor race ways can be connected both as one-phase and three-phase without taking into account how the phases R, S and T are mounted, which was the case in connection with previously known distribution boards.

No matter where one-phase or three-phase race ways are chosen in horizontal or vertical direction, the cyclic alteration between the phases will always give the correct phases independent of which elements have been used previously.

Aside from rendering the advantage that the electrician does not have to think of the distribution of the different conductor runs between the three incoming phases, the present distribution board also includes the advantage of making the assembly work easier for the electrician, the physical dimensions of the board also being smaller as compared with known boards.

It is to be understood that the above described embodiment can be varied within wide limits without transgressing the scope of the invention. For example, a distribution board according to the invention can be implemented with other elements and other locations thereof than what has been illustrated in the drawing. For example, the zigzag-shaped bus systems can be expanded to involve not only three columns but for example four, five or six. When using six columns, two such systems as illustrated in Fig. la, may appropri¬ ately be built together, but it is to be understood that the bus systems not necessarily must have a strict zigzag-form, but can, of course, include extensions at suitable locations thereof, such extensions with their points of contacts also giving an alternating sequence of the phases, R, S, T in the same manner as illustrated in the example of Fig. la.

It is further to be understood that a distribution board according to the invention can also include main fuses, the connection to the individual bus systems then being accomplished from the connection clamps via the main fuses. In the example illustrated in Fig. la a connection may appropriately be made direct to the main connection clamps 2R, 2S and 2T via for example a fuse disconnecting switch.

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Claims (7)

P a t e n t C l a i m s;

1. Distribution board for electrical installations in which an incoming three-phase system is distributed between single-phase and three-phase conductor race ways, c h a r a c t e r i z e d i n ^' that it comprises a bus system (5R, 5S, 5T) which distributes the three incoming phases (R, S and T) in rows (RO) and columns (CO) of race way connection points (at 7R, 7S, 7T and at 16, respectively) , so that the phases (R, S and T) are alternated sequentially both along the rows (RO) and columns (CO) of the connection points (at 7R, 7S, 7T and at 16,. respectively) .

2. Distribution board as claimed in claim 1, c h a r a c t e r i z e d i n that it comprises at least three rows (RO) of race way connection points, each column (CO) comprising three connection points (at 4RR, 4TT and 4SS, and at 16, respectively) , and that each connection point which belongs to one of the phases (R or S or T) is connected by buses (5R, 5S, 5T) running in zigzag.

3. Distribution board as claimed in claim 1 or 2, c h a r a c t e r i z e d i n that the distribution board (1, 13, 22) is designed as a completed module with preconnected bus systems and comprising fuse holders (14) and fuse elements (24, 25, 26).

4. Distribution board as claimed in any of the pre¬ ceding claims, c h a r a c t e r i z e d i n that it comprises a bottom plate (1) of electrical insulating material carrying bus systems (5R, 5S, 5T) for the distribution of race way connection points (7R, 7S , 7T) as well as a connection or element plate (13) which is

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/». WIPO provided above the bus system (5R, 5S and 5T) and made of electrical insulating material "carrying f se element holders (14) with connection clamps (16) for the race ways as well as a cover (22) for touch protection of the connection clamps (16) .

5. Distribution board as claimed in claim 4, c h a r a c t e r i z e d i n that bus carrying guiding lugs (4RR, 4SS, 4TT) of different heights are mounted on the bottom plate (1) , lugs carrying buses belonging to the same phase having the same height but different from the lug height of the other phases so that buses (5R or 5S or 5T) for each phase (R, S and T, respectively) extend in the same plane, which is diffe¬ rent from the planes of the other phases.

6. Distribution board as claimed in claim 4 or 5, c h a r a c t e r i z e d i n that on the bottom side of the element/connection plate (13) there are provided supporting lugs (21) having a size and location being so adapted to the planes of the buses that they keep the buses (5R, 5S, 5T) in position on the bus carrying guiding lugs (4RR, 4SS, 4TT) .

7. Distribution board as claimed in any of the claims 4-6, c h a r a c t e r i z e d i n that in the area of the bus carrying guiding lugs (4RR, 4SS, 4TT) there is mounted a bimetallic disc (6) serving to provide a temperature dependent pressure against the buses (5R, 5S, 5T) from the guiding lugs (4RR, 4SS, 4TT) .

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