Terminal protection cover of current transformer with excellent protection performance

Abstract

The present invention relates to a protective cover for a current transformer terminal, comprising a body portion that encloses the terminal, a corrugated tube portion that encloses the cable, and guide portions formed on both sides of the lower opening of the body portion. Anti-detachment plates are formed at mutually staggered positions on both guide portions to prevent the protective cover from detaching while installed. A connection color mark according to the current transformer-electricity meter connection rule is displayed on the body portion to prevent incorrect wiring.

Description

Technology Field

[0001] The present invention relates to a protective cover for current transformer terminals, and more specifically, to a protective cover for current transformer terminals that surrounds and protects the terminals so that both terminals of the current transformer are not exposed to the outside. Background Technology

[0002] Instrument current transformers, generally referred to as 'CTs', convert large currents into small currents and supply them to measuring instruments (electricity meters, power meters), thereby enabling the instruments to measure power consumption at the point of use without directly utilizing the large currents.

[0003] Current transformers come in direct-connection and through-through types. While the through-through type, which does not require cable cutting, is sometimes used for general in-house meter reading, the direct-connection type, which offers lower error margins, is installed when power meters are mounted for KEPCO meter reading.

[0004] FIG. 1 illustrates the installation state of a direct-connection type current transformer (since the current transformer discussed in this specification is a direct-connection type current transformer, the term 'current transformer' below will refer to a direct-connection type current transformer).

[0005] Since power is supplied in three phases, a current transformer (2) is installed for each cable (1) corresponding to each phase (R, S, T). Terminals (2a, 2b) are provided at both ends of the current transformer (2) to connect the cable (1).

[0006] The power meter (3) is provided with terminals P1, P2, and P3 for voltage measurement, terminals 1S, 2S, 3S, 1L, 2L, and 3L for current measurement, and a ground terminal P0 (total of 10 terminals). The voltage measurement terminals are connected to the power side terminal (2a) of the current transformer (2), and the current measurement terminals are connected to the secondary side terminals (2c, 2d) provided on the body of the current transformer (2). The ground terminal is connected to the N-phase cable (not shown) and the terminals corresponding to 1L, 2L, and 3L among the secondary side terminals of the current transformer (2) as a common connection.

[0007] At this time, the wiring work is carried out using seven predetermined colors of wires to prevent incorrect wiring and ensure accurate readings. P1 - red, P2 - white, P3 - blue are used as voltage wires, 1S,1L - yellow, 2S,2L - brown, 3S,3L - black are used as current wires, and green is used as the ground wire.

[0008] However, in the past, even after the connection of the current transformer (2) and the power meter (3) was completed, the terminals (2a, 2b) on both sides of the current transformer (2) were left exposed to the outside, so there was a high risk of electric shock.

[0009] Therefore, insulation taping was performed, but the work was not only cumbersome, but complete taping was also difficult due to the voltage line connection part, so it was still not possible to prevent the live part from being exposed to the outside.

[0010] In addition, 7-color wiring is used to prevent incorrect wiring, but there was a possibility that incorrect wiring could occur at any time if the worker's attention was reduced. Prior art literature

[0011] Republic of Korea Registered Patent Publication No. 10-0333953 (Published April 22, 2002) The problem to be solved

[0012] Accordingly, the present invention was devised to solve the above-mentioned problems and aims to provide a current transformer terminal protective cover that reduces the risk of electric shock and helps improve wiring accuracy. means of solving the problem

[0013] The present invention for achieving the above-mentioned purpose comprises: a body portion having an internal space that is open downward to surround a terminal of a current transformer; a corrugated tube portion formed at one end of the body portion and having an opening downward to surround a cable connected to the terminal; and plate-shaped guide portions protruding downward from both sides of the downward opening of the body portion.

[0014] An embossing section is formed on the inner surface of the above-mentioned corrugated tube, in which a number of bosses made of a soft rubber material are formed.

[0015] A detachment prevention plate is formed protruding from each of the above two guide sections to block the opening of the body section.

[0016] The above-mentioned two guide sections are formed at different positions along the length of the body section so as not to overlap each other.

[0017] A plurality of teeth are formed at each of the mutually facing ends of the two guide parts mentioned above, and the teeth on both sides mesh with each other.

[0018] A connection color mark according to the current transformer-electricity meter connection rule is displayed on the above body part.

[0019] The above connection color mark includes a voltage line color mark indicating the color of the voltage line connected to the power side terminal of the current transformer, and a current line color mark indicating the color of the current line connected to the secondary side terminal of the current transformer.

[0020] The above voltage line color mark is displayed in a band shape on one side of the body part, and is displayed in red on the R-phase protective cover, white on the S-phase protective cover, and blue on the T-phase protective cover.

[0021] The above current line color mark is displayed in a circular shape on one side of the body part, and is displayed in yellow on the R-phase protective cover, brown on the S-phase protective cover, and black on the T-phase protective cover. Effects of the invention

[0022] According to the present invention as described above, a protective cover capable of completely enclosing both terminals of a current transformer is provided.

[0023] The installation of the above protective cover prevents external exposure of the charging part, thereby significantly reducing the risk of electric shock accidents during current transformer replacement, power meter replacement, and instrument testing.

[0024] In addition, the aforementioned protective cover is marked with a connection color mark of the same color as the connection wire color for each phase, which is of great help in preventing incorrect wiring when installing current transformers and electricity meters. Brief explanation of the drawing

[0025] FIG. 1 is a diagram showing the installation state of a current transformer according to the prior art. FIG. 2 is a front view of a current transformer terminal protective cover according to the present invention, where (a) is a protective cover for the R phase, (b) is a protective cover for the S phase, and (c) is a protective cover for the T phase. Figure 3(a) is a top view of the protective cover, (b) is a bottom view of the protective cover, and (c) is an enlarged view of the anti-detachment plate formed on the bottom surface of the protective cover. Figure 4 is a diagram explaining the installation process of the protective cover. Figure 5 is a diagram showing the installation state of the protective cover. Figure 6 is a cross-sectional view of the installation state of the corrugated pipe section of the protective cover. FIG. 7 is a drawing showing the state in which current transformers and protective covers are installed on all three-phase power supply cables. Specific details for implementing the invention

[0026] The present invention is susceptible to various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention. The thickness of lines or the size of components, etc., illustrated in the attached drawings may be exaggerated for clarity and convenience of explanation.

[0027] Furthermore, the terms described below are defined in consideration of their functions in the present invention, and these may vary depending on the intent of the user or operator or case law. Therefore, the definitions of these terms should be based on the content throughout this specification.

[0028] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. Regarding the connection structure of the current transformer and the power meter, Figure 1, which was referenced in the description of the prior art, will be used, and the same reference numerals for each component will be used.

[0029] As illustrated in FIGS. 2 and 3, the current transformer terminal protection cover according to the present invention comprises a U-shaped body portion (10) that is open downward, a corrugated tube portion (20) formed at one end of the body portion (10), and thin plate-shaped guide portions (30) formed on both sides of the downward opening of the body portion (10). The body portion (10), the corrugated tube portion (20), and the guide portions (30) are made of a rubber or plastic material that does not conduct current.

[0030] The above body part (10) has a generally rectangular shape in both its front and flat surfaces. Inside the body part (10), a space is provided to accommodate one terminal (2a, 2b) of a current transformer (2), and the sides and bottom of the terminal receiving space are open to the outside so that the terminal (2a, 2b) can be inserted into the internal terminal receiving space.

[0031] The corrugated tube portion (20) is formed at one end of the body portion (10) and is a part that wraps around the cable (1) connected to the terminals (2a, 2b). The corrugated tube portion (20) is also formed with an open structure with an open bottom, just like the body portion (10), so that a protective cover can be placed over the current transformer (2) terminals (2a, 2b) and the cable (1) connection part.

[0032] The guide portion (30) is a flat plate-shaped part formed protruding downward at both ends of the lower opening of the body portion (10). The guide portion (30) serves to guide the insertion path of the terminals (2a, 2b) so that they can be easily inserted into the inside of the body portion (10) when the protective cover is installed. In addition, the guide portion (30) provides a location where the anti-detachment plate (40), which will be described later, is formed.

[0033] The anti-detachment plate (40) is a flat protruding plate formed horizontally protruding from both guide parts (30), and the anti-detachment plates (41, 42) (see Fig. 3 (b)) are formed at positions offset from each other in the longitudinal direction of the body part (10) so as not to interfere with each other.

[0034] At the mutually facing ends of the two anti-detachment plates (41, 42), teeth (41a, 41b) with small differences in height between the peaks and valleys are formed. These teeth (41a, 41b) normally connect with each other to improve the connection strength of the anti-detachment plates (41, 42), and when a worker artificially opens the two sides of the body part (10), the connection state can be released without applying great force due to the elastic deformation of the anti-detachment plates (41, 42).

[0035] The above corrugated tube portion (20) is formed with a shape in which the diameter decreases stepwise from the body portion (10) toward the end portion, and is structured so that the outer shape can be freely expanded or contracted according to the diameter of the cable (1) inserted inside (see FIG. 6).

[0036] Therefore, even if the diameter of the cable (1) connected to the current transformer (2) changes (decreases or increases), the corrugated pipe section (20) expands and contracts accordingly to wrap around the cable (1), thereby making the installation of the protective cover secure.

[0037] Additionally, an embossing portion (21) with multiple bosses made of soft rubber material may be formed on the inner surface of the corrugated tube portion (20). Therefore, when the protective cover is installed, the embossing portion (21) adheres to the surface of the cable (1), and the adhesion force in the front-rear direction (longitudinal direction of the cable) is improved, which helps the protective cover maintain its installation position stably.

[0038] FIG. 4 shows the process of installing a protective cover with the structure described above. The worker places the protective cover on the upper part of the terminal (2a) to be installed, spreads the two sides of the body part (10) to secure an insertion path for the terminal (2a) between the two sides of the anti-detachment plates (41, 42), and covers the terminal (2a) with the body part (10) so that the terminal (2a) is inserted into the inside of the body part (10). Afterward, when the force holding the two sides of the body part (10) apart is removed, the two sides close up again, and the teeth (41a, 42a) of the two sides of the anti-detachment plates (41, 42) engage with each other. At this time, the corrugated tube part (20) is also placed on the outside of the cable (1) in the same manner as the body part (10).

[0039] Through the process described above, a protective cover is installed as shown in FIGS. 5 to 7, and the protective cover completely covers the terminal (2a) of the current transformer (2), thereby preventing an electric shock accident caused by the exposure of the terminal (2a).

[0040] At this time, as described above, the detachment of the terminal (2a) from the inside of the body part (10) is suppressed by the above-described detachment prevention plates (41, 42), and in addition, the installation state of the protective cover can be maintained very firmly and stably by the above-described corrugated tube part (20) holding the cable (1) in close contact.

[0041] With the protective cover installed, the voltage line (P1) connected to the terminal (2a; power side terminal) extends to the outside of the protective cover through the opening in front of the anti-detachment plate (41, 42).

[0042] Meanwhile, as shown in FIG. 2, the protective cover according to the present invention may have connection color marks (M1, M2) corresponding to each phase (R, S, T) of the three-phase current in accordance with the seven-color wire connection rules of the current transformer (2) and the power meter (3).

[0043] The above wire color marks (M1, M2) include a voltage wire color mark (M1) displayed in a vertical band shape on the side of the body of the body part (10) and a current wire color mark (M2) displayed in a circular shape on one corner of the body of the body part (10). These voltage wire color marks (M1) and current wire color marks (M2) can be displayed anywhere on the body part (10), but it is preferable to display them on the rear end of the body part (10) as shown in FIG. 2 so that the worker can easily see the color of the mark even while holding the protective cover with their hand.

[0044] As shown in Fig. 2 (a), the protective cover installed on the power side terminal (2a) of the current transformer connected to the R-phase cable has the voltage line color mark (M1) marked in red and the current line color mark (M2) marked in yellow.

[0045] And as shown in Fig. 2 (b), the protective cover installed on the power side terminal (2a) of the current transformer connected to the S-phase cable has the voltage line color mark (M1) displayed in white and the current line color mark (M2) displayed in brown.

[0046] And as shown in Fig. 2 (c), the protective cover installed on the power side terminal (2a) of the current transformer connected to the T-phase cable has the voltage line color mark (M1) marked in blue and the current line color mark (M2) marked in black.

[0047] As described above, if a protective cover marked with a voltage line color mark (M1) and a current line color mark (M2) according to the current transformer-electricity meter connection rule is placed over the cable (1) of the input terminal (2a) of the corresponding phase current transformer and the connection work between the current transformer (2) and the electricity meter (3) is performed, the color of the wire connected to each phase current transformer can be visually checked immediately, which helps prevent errors in the connection work.

[0048] In addition, after completing the wiring work and properly installing the protective cover of each phase on the outside of the corresponding terminal (2a) as shown in Fig. 7, when checking the wiring status to see if the wiring was done correctly, the wiring color marks (M1, M2) on the protective cover and the color of the wire connected to the corresponding current transformer (2) can be checked to immediately and easily check for any abnormalities in the wiring status.

[0049] As described above, since the wiring work and wiring status check work for the current transformer (2) and the power meter (3) can be performed intuitively and very simply, wiring errors do not occur, and thus accurate meter readings can always be achieved.

[0050] Meanwhile, as shown in FIG. 7, since a protective cover with connection color marks (M1, M2) marked only on the power side terminal (2a) of the two terminals of the current transformer (2) as described above can be used, it is acceptable to use an unmarked protective cover without connection color marks (M1, M2) marked on the load side terminal (2b).

[0051] As described above, the present invention has been explained with reference to the embodiments illustrated in the drawings, but this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the true technical scope of protection of the present invention should be determined by the claims below. Explanation of the symbols

[0052] 1 : Cable 2 : Current transformer 2a: Power side terminal 2b: Load side terminal 2c, 2d: Current transformer secondary terminals 3: Electricity meter 10 : Body part 20 : Corrugated tube part 21 : Embossing section 30 : Guide section 40, 41, 42: Anti-detachment plates 41a, 42a: Teeth M1: Voltage line color mark M2: Current line color mark

Claims

Claim 1 A body portion having an internal space that opens downward to enclose the terminal of a current transformer; a corrugated tube portion formed at one end of the body portion and having an opening downward to enclose a cable connected to the terminal; a plate-shaped guide portion protruding downward from both sides of the downward opening of the body portion; and a pair of anti-detachment plates each protruding from the two guide portions and blocking the opening of the body portion. It includes a voltage line color mark indicating the color of the voltage line connected to the power side terminal of the current transformer and a current line color mark indicating the color of the current line connected to the secondary side terminal of the current transformer, and a connection line color mark displayed on the body part according to the current transformer-electricity meter connection rule; wherein a plurality of teeth are formed at each of the mutually facing ends of the two guide parts, and the two teeth mesh with each other; the corrugated tube part is formed in a shape in which the diameter gradually decreases from the body part side toward the end, and an embossing part is formed on the inner surface of the corrugated tube part in which a plurality of bosses made of soft rubber material are formed; the voltage line color mark and the current line color mark are displayed on the rear end of the body part so that the mark color can be easily seen even while the operator is holding the protective cover with their hand; the two guide parts are formed at different positions in the longitudinal direction of the body part so as not to overlap each other; the voltage line color mark is displayed in a band shape on one side of the body part, and is red for the R-phase protective cover, white for the S-phase protective cover, and on the T-phase protective cover A current transformer terminal protective cover with excellent protective performance, characterized by being marked in blue, with the current line color mark being marked in a circular shape on one side of the body part, and marked in yellow on the R-phase protective cover, brown on the S-phase protective cover, and black on the T-phase protective cover.

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