JP3912330B2 - Lightning protection circuit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lightning protection circuit for protecting various electronic devices used by a commercial power source from induced lightning.
[0002]
[Prior art]
DESCRIPTION OF RELATED ART Conventionally, it describes in following patent document 1-patent document 3 for the purpose of protection with respect to the lightning surge of electronic devices, such as a communication apparatus provided with input / output lines, such as another communication line and an antenna line, connected with a commercial power source. As described, table taps, outlets with a lightning protection function, and lightning protection adapters that employ a technique called the bypass arrester method are known.
[0003]
The technology that uses this bypass arrester method is to connect the earth of the protector on the communication line side to the earth of the lightning protector on the power line side. When the surge goes to the ground through the ground, the potential generated at one ground is prevented from being applied to the other ground as a lightning surge. As a result, in the conventional technology, communication devices and the like can be completely protected against lightning surges.
[0004]
[Patent Document 1]
JP 2000-37035 A
[Patent Document 2]
JP-A-2000-106255 [0006]
[Patent Document 3]
JP-A-9-182276
[Problems to be solved by the invention]
However, the conventional technique has a problem in that the invasion route to the electronic device of lightning surge is not sufficient. Therefore, in the prior art, it is necessary to consider the lightning protection on the power line side and the lightning protection on the signal input / output line side separately. In addition, with the conventional technology, it is difficult to select a lightning protection element that constitutes a lightning protection circuit, so it is difficult to design a lightning protection circuit with an accurate overvoltage level to be removed. It was difficult to design a lightning protection circuit.
[0008]
Conventionally, there is a bound charge theory known in the IEEJ Technical Report No. 522 as various theories regarding the path of lightning surges to enter electronic equipment. In spite of this, a lightning protection circuit that protects electronic devices against a lightning surge intrusion path based on this bound charge theory has been proposed. That is, in a conventional electronic device, a lightning protection circuit is designed so that a lightning surge can be removed from a power line or a communication line to a ground line.
[0009]
Therefore, the present invention has been proposed in view of the above-described circumstances, and reliably protects lightning surges on electronic devices having commercial power lines and signal input / output lines, and increases the design margin of electronic devices. An object of the present invention is to provide a lightning protection circuit that can be used.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problem, in the present invention, a surge voltage is applied to an electronic device based on a potential difference between the ground between the input / output line and the power supply line or between the ground terminal of the electronic device and the power supply line. In view of this, a lightning protection circuit provided with a surge absorber for protecting an electronic device against a lightning surge is provided.
[0011]
That is, the lightning protection circuit according to the present invention includes a first surge absorber that includes one first input / output line of the plurality of input / output lines and one first power supply line of the plurality of power supply lines. The second surge absorber is electrically connected to a second input / output line different from the first input / output line and a second power supply line different from the first power supply line. The third surge absorber is electrically connected to an electric wire connecting the first surge absorber and the first power supply line, and the second surge absorber and the second power supply are provided. Electrically connected to an electric wire connecting between the wires, or electrically connected to an electric wire connecting between the first surge absorber and the first input / output line, and the second surge absorption with wire in provided so as to be electrically connected structure for connecting the vessel and the second input line To solve the problems described above.
[0012]
In another lightning protection circuit according to the present invention, the first surge absorber is connected to one first input / output line of the plurality of input / output lines and one first power supply of the plurality of power supply lines. The second surge absorber is electrically connected to a second input / output line different from the first input / output line and a second power supply line different from the first power supply line. The above-described problems are solved by providing the third surge absorber so as to electrically connect the plurality of input / output lines.
[0013]
Furthermore, another lightning protection circuit according to the present invention electrically connects the first surge absorber to one first input / output line of a plurality of input / output lines and a power line corresponding to a neutral line. The second surge absorber is provided so as to be connected, and is configured to electrically connect a second input / output line different from the first input / output line and a power supply line corresponding to the neutral line. This solves the above-mentioned problem.
[0014]
Furthermore, another lightning protection circuit according to the present invention includes a surge absorber provided so as to electrically connect a ground terminal provided in an electronic device and a power line corresponding to a neutral wire. The above-mentioned problem is solved.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
[First configuration example of lightning protection circuit]
The present invention is applied to a lightning protection circuit according to a first configuration example configured as shown in FIG. 1, for example.
[0017]
This lightning protection circuit is connected to a telephone or FAX 1 having a power line, and is housed in the same casing as the telephone or FAX 1. The telephone or FAX 1 is connected to two communication lines 2A and 2B and to two power lines 3A and 3B. As a result, the telephone or FAX 1 is activated upon receiving power supply from the power supply lines 3A and 3B connected to the commercial power supply, and transmits and receives various signals by connecting to the telephone line and the like via the communication lines 2A and 2B.
[0018]
The lightning protection circuit includes a first surge absorber 11 that is electrically connected between the communication line 2A and the power line 3A, and a second surge absorber that is electrically connected between the communication line 2B and the power line 3B. 12 and a third surge absorber 13 that is electrically connected between the first surge absorber 11 and the second surge absorber 12.
[0019]
The 1st surge absorber 11, the 2nd surge absorber 12, and the 3rd surge absorber 13 are provided with the surge protection element which has voltage dependence, for example. The surge protection element has a high resistance in a normal state, and limits the voltage value by rapidly decreasing the resistance when the applied voltage exceeds a predetermined voltage. In addition, as the surge protection element, an element that limits the lightning surge voltage to a voltage that is lower than the withstand voltage of the telephone or FAX 1 is selected.
[0020]
Such a lightning protection circuit electrically bypasses between the communication line 2A and the power line 3A by the first surge absorber 11, and between the communication line 2B and the power line 3B by the second surge absorber 12. It is electrically bypassed. Thus, in the lightning protection circuit, the lightning surge voltage applied between the communication line 2A and the power supply line 3A is limited by the first surge absorber 11, and is applied between the communication line 2B and the power supply line 3B. The lightning surge voltage is limited by the second surge absorber 12, and the lightning surge voltage applied between the communication line 2A and the communication line 2B, and the power supply line 3A and the power supply line 3B is limited by the third surge absorber 13. In this lightning protection circuit, the lightning surge applied between the communication line 2A and the power supply line 3B is further restricted by the first surge absorber 11 and the third surge absorber 13, and the communication line 2B and the power supply line are restricted. The lightning surge applied between 3A is limited by the second surge absorber 12 and the third surge absorber 13.
[0021]
In addition, in this example, although the case where the 3rd surge absorber 13 was connected to the power supply lines 3A and 3B side of the 1st surge absorber 11 and the 2nd surge absorber 12 was shown, not only this but 1st The surge absorber 11 and the second surge absorber 12 may be connected to the communication lines 2A and 2B.
[0022]
The lightning protection circuit configured as described above has a first surge in order to protect the telephone or the FAX 1 against the lightning surge by paying attention to the potential difference between the grounds among the intrusion paths of the lightning surge that exist in many cases regarding the telephone or the FAX 1. An absorber 11, a second surge absorber 12 and a third surge absorber 13 are provided.
[0023]
In other words, it is sometimes argued that induced lightning is caused by the influence of an electromagnetic field, but if a lightning surge enters the telephone or FAX 1 due to the influence of the electromagnetic field, induction to the steel frame of the building or all electrons Equipment will be affected. However, in reality, failures of electronic devices due to lightning surges are often limited to televisions and telephones. All such electronic devices have two or more grounding points. As the two or more grounding points, for example, two grounding points can be considered among the power source grounding points of the B type contact, the D type contact of the commercial power supply, the protector in the communication device, or the device interconnected by the signal line.
[0024]
The ground to which lightning surges are induced has a large capacity and is often used as a potential reference for electronic devices. However, a grounding resistance exists and a potential difference occurs between the grounds.
[0025]
Therefore, in the lightning protection circuit to which the present invention is applied, it is the potential difference between the ground potential of the communication lines 2A and 2B and the ground potential of the power supply lines 3A and 3B that causes lightning surge to the electronic device as induced lightning. It is said. That is, in the lightning protection circuit, the grounding point between the communication lines 2A, 2B and the power supply lines 3A, 3B is bypassed by the first surge absorber 11, the second surge absorber 12, and the third surge absorber 13. The lightning surge voltage due to the induced lightning applied to the telephone or the FAX 1 can be surely limited to reliably protect the telephone or the FAX 1 from the lightning surge.
[0026]
Further, according to this lightning protection circuit, when the lightning surge intrusion route is not clear and complicated, a large number of surge absorbers are required and the telephone or FAX 1 is securely connected to the lightning surge voltage. Although it was difficult to protect against lightning surges, the number of surge absorbers can be reduced by clarifying the lightning surge intrusion route, increasing the design margin and improving the lightning surge protection performance. it can.
[0027]
Furthermore, in this lightning protection circuit, the value of the combination of the communication lines 2A and 2B and the power supply lines 3A and 3B to which the lightning surge voltage is applied is the number (2) of the communication lines 2A and 2B and the power supply lines 3A and 3B. The value (4) obtained by multiplying the number (2) is obtained by connecting the third surge absorber 13 between the first surge absorber 11 and the second surge absorber 12, so that The protection of FAX 1 can be realized with a minimum number of three surge absorbers.
[0028]
That is, assuming that the total number of communication lines and power supply lines is N, the lightning protection circuit can be wired over the entire line with the minimum number of (N−1) surge absorbers. Therefore, according to this lightning protection circuit, even if the communication lines 2A and 2B are connected to the ground via a protector or a grounding terminal of another device, the lightning surge voltage applied to the telephone or FAX 1 is surely limited. can do.
[0029]
Furthermore, as shown in FIG. 2, the lightning protection circuit according to the first configuration example may be configured to be connected to the TV / video recording / reproducing device 21 as an electronic device. This lightning protection circuit is housed in the same housing as the TV / video recording / reproducing device 21. The TV / video recording / reproducing device 21 is connected to a plurality of antenna lines 22A and 22B and to a plurality of power supply lines 3A and 3B. As a result, the TV / video recording / reproducing device 21 is activated by receiving power supply from the power supply lines 3A and 3B connected to the commercial power supply, and receives a television signal through the antenna lines 22A and 22B.
[0030]
In this lightning protection circuit, the antenna line 22A and the power line 3A are electrically connected by the first surge absorber 11, the antenna line 22B and the power line 3B are electrically connected by the second surge absorber 12, The first surge absorber 11 and the second surge absorber 12 are electrically connected by the third surge absorber 13.
[0031]
In this way, even in the case shown in FIG. 2, the TV / video recording / reproducing device 21 can be reliably protected from lightning surge as in the case of FIG.
[0032]
[Second configuration example of lightning protection circuit]
Next, a lightning protection circuit according to a second configuration example to which the invention is applied will be described.
[0033]
As shown in FIG. 3, the lightning protection circuit according to the second configuration example is connected to the communication device 31 and accommodated in the same casing as the communication device 31. The communication device 31 is connected to the four communication lines 2A, 2B, 2C, and 2D, and is connected to the two power supply lines 3A and 3B. Accordingly, the communication device 31 is activated upon receiving power supply from the power supply lines 3A and 3B connected to the commercial power supply, and transmits and receives various signals through the communication lines 2A, 2B, 2C, and 2D.
[0034]
In addition, this lightning protection circuit replaces the third surge absorber 13 in the first configuration example with the fourth surge absorbers 14A and 14B that electrically connect the four communication lines 2A, 2B, 2C, and 2D. , 14C. In such a lightning protection circuit, the lightning surge voltage applied between the communication line 2C and the power supply line 3A is limited by the first surge absorber 11, and is applied between the communication line 2D and the power supply line 3B. The lightning surge voltage is limited by the second surge absorber 12. Lightning surges applied between other communication lines and power lines are limited by the combination of surge absorbers in the path. Specifically, the lightning protection circuit is limited by the fourth surge absorbers 14A, 14B, 14C and the second surge absorber 12 between the communication line 2A and the power supply line 3B. The lightning protection circuit limits the lightning surge voltage applied between the communication line 2A and the communication line 2B by the fourth surge absorber 14A, and the lightning applied between the communication line 2B and the communication line 2C. The surge voltage is limited by the fourth surge absorber 14B, and the lightning surge voltage applied between the communication line 2C and the communication line 2D is limited by the fourth surge absorber 14C.
[0035]
In such a lightning protection circuit, as in the first configuration example, the value of the combination of the communication lines 2A, 2B, 2C, and 2D and the power supply lines 3A and 3B to which the lightning surge voltage is applied is equal to the number of communication lines (4 ) And the number (2) of the power supply lines 3A and 3B (8), but by connecting the fourth surge absorbers 14A, 14B and 14C between the communication lines 2A, 2B, 2C and 2D, The protection of the communication device 31 against the surge voltage can be realized with a minimum number of five surge absorbers.
[0036]
That is, assuming that the total number of communication lines and power supply lines is N, the lightning protection circuit can be wired over the entire line with the minimum number of (N−1) surge absorbers. Therefore, according to this lightning protection circuit, even if the communication lines 2A, 2B, 2C, and 2D are connected to the ground via a protector or a ground terminal of another device, the lightning that is reliably applied to the communication device 31 Surge voltage can be limited.
[0037]
Further, according to this lightning protection circuit, as in the first configuration example, it is of course possible to improve the reliability and increase the design margin by reliably protecting the communication device 31 against lightning surge.
[0038]
In this example, an example in which the fourth surge absorbers 14A, 14B, and 14C are provided in place of the third surge absorber 13 has been described, but the first surge absorber 11 and the second surge absorber 12 are connected. When the third surge absorber 13 is provided, the fourth surge absorber 14C can be omitted, and the lightning surge voltage with respect to the communication device 31 can be surely limited.
[0039]
[Third configuration example of lightning protection circuit]
Next, a lightning protection circuit according to a third configuration example to which the invention is applied will be described.
[0040]
As shown in FIG. 4, the lightning protection circuit according to the third configuration example is connected to the solar power conditioner 41 and accommodated in the same housing as the solar power conditioner 41. The solar power conditioner 41 is connected to a plurality of solar cell input lines 43A and 43B connected to a solar cell (not shown) and is connected to single-phase three-wire power lines 42A, 42B and 42C. Thereby, in the solar power conditioner 41, it starts by receiving the power supply from the power supply lines 42A, 42B, and 42C connected to the commercial power supply, and adjusts the power of the solar battery by the solar battery input lines 43A and 43B. Here, the power lines 42A and 42B are voltage lines, and the power line 42C is a neutral line connected to the ground line.
[0041]
Such a lightning protection circuit electrically connects one of the first surge absorber 11 and the second surge absorber 12 to the solar cell input line 43A and the solar cell input line 43B, respectively, The other of the second surge absorber 12 is electrically connected to the power line 42C (N line).
[0042]
In such a lightning protection circuit, the power supply lines 42A, 42B, 42C and the solar cell input lines 43A, 43B are electrically connected to bypass the solar power conditioner 41 against the lightning surge. Can be protected.
[0043]
In addition, in the first configuration example and the second configuration example, since it is not known which of the power supply lines is the ground line, a surge absorber is connected to each of the power supply lines 3A and 3B, but the solar power conditioner 41 is Since it is connected to the single-phase three-wire power lines 42A, 42B, and 42C, it is possible to connect the first surge absorber 11 and the second surge absorber 12 to the power line 42C that is always connected to the ground line. Therefore, the solar power conditioner 41 can be protected.
[0044]
That is, in this lightning protection circuit, as in the first configuration example, the combination of the solar cell input lines 43A, 43B and the power supply lines 42A, 42B, 42C to which the lightning surge voltage is applied is the solar cell input line 43A, The value (6) is obtained by multiplying the number (2) of 43B and the number (3) of the power supply lines 42A and 42B, but the first surge absorber 11 and the second surge absorber 12 are connected only to the power supply line 42C. Thus, if the value obtained by adding the numbers of the solar cell input lines 43A, 43B and the power supply lines 42A, 42B, 42C is N, the lightning protection circuit uses the minimum number of (N-3) surge absorbers. Wiring can be performed over the entire line.
[0045]
Further, according to this lightning protection circuit, as in the first configuration example, it is possible to improve the reliability and increase the design margin by surely protecting the solar power conditioner 41 against the lightning surge. is there.
[0046]
[Fourth configuration example of lightning protection circuit]
Next, a lightning protection circuit according to a fourth configuration example to which the invention is applied will be described.
[0047]
As shown in FIG. 5, the lightning protection circuit according to the fourth configuration example is connected to the electric device 51 and is housed in the same casing as the electric device 51. The electrical device 51 includes a ground terminal 52 and is connected to single-phase three-wire power lines 42A, 42B, and 42C.
[0048]
In this lightning protection circuit, the fifth surge absorber 15 is provided so as to electrically connect the power supply line 42C corresponding to the N line and the ground terminal 52 among the power supply lines 42A, 42B, and 42C.
[0049]
In such a lightning protection circuit, it is possible to bypass the electrical connection between the power supply lines 42A, 42B, and 42C and the ground terminal 52 and protect the electrical device 51 against a lightning surge.
[0050]
In this lightning protection circuit, since the electric device 51 is connected to the single-phase three-wire power lines 42A, 42B, and 42C, the fifth surge absorber 15 is connected only to the power line 42C as in the third configuration example. It is possible to protect the electric device 51 against lightning surges simply by connecting to.
[0051]
Further, according to this lightning protection circuit, as in the first configuration example, it is of course possible to improve the reliability and increase the design margin by reliably protecting the electric device 51 against the lightning surge.
[0052]
The above-described embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and various modifications can be made depending on the design and the like as long as the technical idea according to the present invention is not deviated from this embodiment. Of course, it is possible to change.
[0053]
In other words, lightning surge protection for electronic devices is not sufficient with a configuration in which a lightning arrester is simply installed on the power line, but lightning surge can be bypassed by connecting the grounding wire of the electronic device to be protected to the grounding wire of the lightning arrester. And can be protected. Specifically, the TV / video recording / reproducing device 21 is more reliably protected by connecting the antenna lines 22A and 22B of the TV / video recording / reproducing device 21 in FIG. 2 to the grounding line of a lightning arrester arranged outdoors. It becomes possible.
[0054]
【The invention's effect】
According to the lightning protection circuit of the present invention, the surge voltage based on the potential difference between the first input / output line and the first power supply line is absorbed by the first surge absorber, and the second input / output line and the second power supply line are The surge voltage based on the potential difference can be absorbed by the second surge absorber, and the surge voltage based on the potential difference between the power supply lines and between the input and output lines can be absorbed by the third surge absorber. It is possible to reliably protect lightning surges to electronic devices having wires, and to increase the design margin of electronic devices.
[0055]
According to another lightning protection circuit of the present invention, a surge voltage based on a potential difference between the first input / output line and the first power supply line is absorbed by the first surge absorber, Since the surge voltage based on the potential difference between the second power supply line and the second surge absorber can be absorbed by the second surge absorber, and the surge voltage based on the potential difference between the plurality of input / output lines can be absorbed by the third surge absorber. It is possible to reliably protect a lightning surge on an electronic device having a power supply line and a signal input / output line, and to increase the design margin of the electronic device.
[0056]
Furthermore, according to another lightning protection circuit according to the present invention, the surge voltage based on the potential difference between the first input / output line and the power line corresponding to the neutral line is absorbed by the first surge absorber, and the second input / output line is absorbed. The surge voltage based on the potential difference between the power line and the power line corresponding to the neutral line can be absorbed by the second surge absorber, so that lightning surge on electronic equipment having commercial power line and signal input / output line can be surely While protecting, the design margin of an electronic device can be made high.
[0057]
Furthermore, according to another lightning protection circuit according to the present invention, a surge voltage can be absorbed by a surge absorber based on a potential difference between a ground terminal provided in an electronic device and a power line corresponding to a neutral wire. Therefore, it is possible to reliably protect the lightning surge on the electronic device and increase the design margin of the electronic device.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a first configuration example of a lightning protection circuit to which the present invention is applied.
FIG. 2 is a block diagram showing another first configuration example of the lightning protection circuit to which the present invention is applied.
FIG. 3 is a block diagram showing a second configuration example of a lightning protection circuit to which the present invention is applied.
FIG. 4 is a block diagram showing a third configuration example of a lightning protection circuit to which the present invention is applied.
FIG. 5 is a block diagram showing a fourth configuration example of a lightning protection circuit to which the present invention is applied.
[Explanation of symbols]
1 Telephone or FAX
2A, 2B Communication lines 3A, 3B, 42A, 42B, 42C Power line 11 First surge absorber 12 Second surge absorber 13 Third surge absorber 14A, 14B, 14C Fourth surge absorber 15 Fifth surge absorber 21 TV / video recording / reproducing machine 22A, 22B Antenna line 31 Communication device 41 Solar power conditioner 43A, 43B Solar cell input line 51 Electric device 52 Ground terminal

Claims (4)

A lightning protection circuit for an electronic device to which a plurality of input / output lines and a plurality of power supply lines are connected,
A first surge absorber electrically connected to one first input / output line of the plurality of input / output lines and one first power line of the plurality of power supply lines;
A second surge absorber in which a second input / output line different from the first input / output line and a second power supply line different from the first power supply line are electrically connected;
Electrically connected to a wire connecting between the first surge absorber and the first power supply line and electrically connected to a wire connecting between the second surge absorber and the second power supply line Or electrically connected to an electric wire that connects between the first surge absorber and the first input / output line and between the second surge absorber and the second input / output line. A lightning protection circuit comprising: a third surge absorber electrically connected to the connecting electric wire . A lightning protection circuit for an electronic device to which a plurality of input / output lines and a plurality of power supply lines are connected,
A first surge absorber electrically connected to one first input / output line of the plurality of input / output lines and one first power line of the plurality of power supply lines;
A second surge absorber in which a second input / output line different from the first input / output line and a second power supply line different from the first power supply line are electrically connected;
A lightning protection circuit comprising: a third surge absorber that electrically connects the plurality of input / output lines. A lightning protection circuit for an electronic device to which a plurality of input / output lines and a single-phase three-wire power line are connected,
A first surge absorber electrically connected to one first input / output line of the plurality of input / output lines and a power line corresponding to a neutral line;
A lightning protection circuit comprising: a second input / output line different from the first input / output line; and a second surge absorber to which a power supply line corresponding to the neutral line is electrically connected. A lightning protection circuit for an electronic device having a ground terminal and connected to a single-phase three-wire power supply line,
A lightning protection circuit comprising a surge absorber to which the ground terminal and a power line corresponding to a neutral wire are electrically connected.

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