JPS61247225A - Overvoltage protection circuit - Google Patents

Overvoltage protection circuit

Info

Publication number
JPS61247225A
JPS61247225A JP8681385A JP8681385A JPS61247225A JP S61247225 A JPS61247225 A JP S61247225A JP 8681385 A JP8681385 A JP 8681385A JP 8681385 A JP8681385 A JP 8681385A JP S61247225 A JPS61247225 A JP S61247225A
Authority
JP
Japan
Prior art keywords
alarm
fuse
circuit
semiconductor
arrester
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP8681385A
Other languages
Japanese (ja)
Inventor
羽生田 謙
早川 日出夫
尾原 通正
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP8681385A priority Critical patent/JPS61247225A/en
Publication of JPS61247225A publication Critical patent/JPS61247225A/en
Pending legal-status Critical Current

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Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。
(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 〔概要〕 落雷により電子機器1通信機器等の信号線又は電源線に
異常電圧が発生し機器を破壊するのを防ぐ、半導体アレ
スタを用いた過電圧保護回路において、半導体アレスタ
と警報接点警報表示付きヒユーズとを直列に接続したも
のをn段構成とし、半導体アレスタが短絡障害となって
も、n回の半導体アレスタのサージ耐量を越えるサージ
流入塩は間断なく十分過電圧に対し保護出来るようにし
て、過電圧保護に対する信頼性を高くし、又半導体アレ
スタの短絡障害はヒユーズの警報接点又は警報表示によ
りすぐ判明するようにし、すぐ交換可能にし、過電圧保
護に対する信頼性を更に高(したものである。
[Detailed Description of the Invention] [Summary] In an overvoltage protection circuit using a semiconductor arrester, which prevents abnormal voltage from occurring in the signal line or power line of electronic equipment 1 communication equipment, etc. due to lightning and destroying the equipment, a semiconductor arrester is used. The n-stage structure consists of a fuse with an alarm contact and an alarm display connected in series, and even if the semiconductor arrester experiences a short-circuit failure, the surge inflow salt that exceeds the surge withstand capacity of the semiconductor arrester will be able to withstand the overvoltage without interruption. The short-circuit failure of the semiconductor arrester can be immediately identified by the fuse alarm contact or alarm display, making it possible to replace it immediately, further increasing the reliability of overvoltage protection. This is what I did.

〔産業上の利用分野〕[Industrial application field]

本発明は、落雷により電子機器9通信機器等の信号線又
は電源線に異常電圧が発生し機器を破壊するのを防ぐ、
半導体アレスタを用いた過電圧保護回路の改良に関する
The present invention prevents abnormal voltage from occurring in the signal line or power line of electronic equipment 9 communication equipment etc. due to lightning and destroying the equipment.
This article relates to improvements in overvoltage protection circuits using semiconductor arresters.

半導体アレスタばサージ耐量を越えるサージ流入により
破壊するが、この時は短絡状態となることが多い。
Semiconductor arresters are destroyed by surges that exceed their surge resistance, but in this case they often become short-circuited.

この為上記過電圧保護回路では、この短絡障害を早く検
出出来ると共に交換する迄の無防備をなくし過電圧保護
の信頼性が高いことが望まれている。
For this reason, it is desired that the above-mentioned overvoltage protection circuit be able to quickly detect this short-circuit fault, eliminate the need for protection until replacement, and have high reliability in overvoltage protection.

〔従来の技術〕[Conventional technology]

第3図は従来例の過電圧保護回路の回路図である。 FIG. 3 is a circuit diagram of a conventional overvoltage protection circuit.

図中20は半導体アレスタ、100は機器、Rは抵抗を
示す。
In the figure, 20 is a semiconductor arrester, 100 is a device, and R is a resistor.

従来半導体アレスタを用いた過電圧保護回路は、第3図
に示す如く、半導体アレスタ20と抵抗Rとを直列接続
した回路を、機器100への信号線又は電源線に並列に
接続し、半導体7レスタ20がサージ耐量を越えるサー
ジ流入により短絡状態になった場合、抵抗Rの両端の電
圧を測定することにより、この回路の漏電流を測定する
ことで、半導体アレスタ20の劣化を判定し短絡障害に
なっていれば交換していた。
As shown in FIG. 3, the conventional overvoltage protection circuit using a semiconductor arrester connects a circuit in which a semiconductor arrester 20 and a resistor R are connected in series to a signal line or a power supply line to a device 100, and connects a semiconductor arrester 20 and a resistor R in parallel. 20 becomes short-circuited due to surge inflow exceeding the surge withstand capacity, by measuring the voltage across the resistor R and the leakage current of this circuit, it is possible to determine the deterioration of the semiconductor arrester 20 and prevent a short-circuit failure. If it had, I would have replaced it.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

しかしながら、従来の過電圧保護回路では、半導体アレ
スタが短絡障害となった場合、漏電流を測定し、半導体
アレスタの短絡障害を検出し交換する迄、次に発生する
過電圧保護に対し正常な保護がされておらず、過電圧保
護に対し信頼性が低い問題点がある。
However, with conventional overvoltage protection circuits, if a semiconductor arrester experiences a short-circuit fault, the leakage current is measured, the short-circuit fault in the semiconductor arrester is detected, and until the semiconductor arrester is replaced, normal protection is not provided against the next overvoltage protection. However, there is a problem that the reliability of overvoltage protection is low.

〔問題点を解決するための手段〕[Means for solving problems]

上記問題点は、過電圧から保護すべき装置に、第1の半
導体アレスタと第1の警報接点付きヒユーズを直列に接
続した回路を電源線又は信号線に並列に接続し、該第1
の警報接点付きヒユーズに、第2の半導体アレスタと第
2の警報接点付きヒユーズを直列に接続した回路を並列
に接続する如く、第n−1の警報接点付きヒユーズに、
第nの半導体アレスタと第nの警報接点付きヒユーズを
直列に接続した回路を並列に接続し、半導体アレスタを
n段構成にするか又は、 第1の半導体アレスタと第1の警報接点警報表示付きヒ
ユーズを直列に接続した第1の回路、及び第2の半導体
アレスタと第2の警報接点警報表示付きヒユーズと該第
1の警報接点警報表示付きヒユーズの警報接点とを直列
に接続した第2の回路、及び第nの半導体アレスタと第
nの警報接点警報表示付きヒユーズと第n−1の警報接
点警報表示付きヒユーズの警報接点とを直列に接続した
第nの回路の合計n個の回路を、過電圧から保護すべき
装置に並列に接続した本発明の手段によりにより解決さ
れる。
The above problem can be solved by connecting a circuit in which a first semiconductor arrester and a first fuse with an alarm contact are connected in series to a power supply line or a signal line in a device to be protected from overvoltage, and
such that a circuit in which a second semiconductor arrester and a second fuse with an alarm contact are connected in series is connected in parallel to the fuse with an alarm contact of the (n-1)th fuse with an alarm contact,
A circuit in which an n-th semiconductor arrester and an n-th fuse with an alarm contact are connected in series is connected in parallel to form an n-stage configuration of the semiconductor arrester, or a first semiconductor arrester and a first alarm contact are provided with an alarm display. a first circuit in which fuses are connected in series; and a second circuit in which a second semiconductor arrester, a second alarm contact, a fuse with an alarm display, and an alarm contact of the first alarm contact and alarm display fuse are connected in series. and an n-th circuit in which the n-th semiconductor arrester, the n-th alarm contact fuse with alarm display, and the n-1 alarm contact of the fuse with alarm display are connected in series, for a total of n circuits. , connected in parallel to the device to be protected against overvoltage, is solved by the measures of the invention.

〔作用〕[Effect]

前者の手段では、第1番目の過電圧サージに対しては、
第1の半導体アレスタが動作し、この半導体アレスタに
サージ耐量を越えるサージの流入があれば、第1の半導
体アレスタは短絡障害となり、第1の警報接点付きヒユ
ーズは溶断し、第2の半導体7レスタが次の過電圧サー
ジに対し機能するようになり、この原理により、n回迄
のサージ耐量を越えるサージ塩の、次々の過電圧サージ
に対して間断なく機能出来るようになり過電圧保護の信
頼性を向上出来る。 又警報接点付きヒユーズの溶断に
より警報接点はオンとなるので、これを用い半導体アレ
スタの短絡障害をすぐ検出出来るため、交換時間が短縮
出来、更に過電圧保護の信頼性を向上出来る。
With the former method, for the first overvoltage surge,
If the first semiconductor arrester operates and a surge exceeding the surge withstand capacity flows into the semiconductor arrester, the first semiconductor arrester becomes a short-circuit failure, the fuse with the first alarm contact melts, and the second semiconductor arrester 7 The resistor will now function against the next overvoltage surge, and based on this principle, it will be able to function without interruption against successive overvoltage surges that exceed the surge resistance up to n times, increasing the reliability of overvoltage protection. I can improve. Furthermore, since the alarm contact is turned on when the fuse with the alarm contact is blown, a short-circuit failure of the semiconductor arrester can be immediately detected using this, so that the replacement time can be shortened and the reliability of overvoltage protection can be improved.

後者の手段では、第1番目の過電圧サージに対しては、
第1の半導体アレスタが動作し、この半導体アレスタに
サージ耐量を越えるサージの流入があれば、第1の半導
体アレスタは短絡障害となり、第1の警報接点警報表示
付きヒユーズは溶断し、警報接点はオンとなり、第2の
半導体アレスタが次の過電圧サージに対し機能するよう
になり、この原理により、n回迄のサージ耐量を越える
サージ塩の、次々の過電圧サージに対して間断な(機能
出来るようになり過電圧保護の信頼性を向上′出来る。
With the latter method, for the first overvoltage surge,
If the first semiconductor arrester operates and a surge that exceeds the surge resistance flows into this semiconductor arrester, the first semiconductor arrester will become short-circuited, the first alarm contact fuse with alarm display will melt, and the alarm contact will be turned off. The second semiconductor arrester is turned on and becomes functional against the next overvoltage surge. Based on this principle, the second semiconductor arrester is activated against successive overvoltage surges that exceed the surge resistance up to n times. This improves the reliability of overvoltage protection.

又警報接点警報表示付きヒユーズの溶断による警報表示
により、半導体アレスタの短絡障害をすぐ検出出来るた
め交換時間が短くなり、更に過電圧保護の信頼性を向上
出来る。
Further, by displaying an alarm by blowing a fuse with an alarm contact alarm display, a short-circuit failure of the semiconductor arrester can be immediately detected, thereby shortening the replacement time and further improving the reliability of overvoltage protection.

〔実施例〕〔Example〕

ζノ 第1図は本発明の実施例の過電圧保護回路の回路図であ
る。
FIG. 1 is a circuit diagram of an overvoltage protection circuit according to an embodiment of the present invention.

図中11〜inは半導体アレスタ、Fil−FInばP
形ヒユーズの如き警報接点警報表示付きヒユーズ、10
0は機器を示す。
In the figure, 11-in is a semiconductor arrester, and Fil-FIn is P.
Fuse with alarm contact alarm display such as type fuse, 10
0 indicates equipment.

第1図では、機器100への信号線又は電源線に、半導
体アレスタ11と警報接点警報表示付きヒユーズFil
を直列に接続した回路を並列に接続し、該警報接点警報
表示付きヒユーズFilに、半導体アレスタ12と警報
接点警報表示付きヒユーズF12を直列に接続した回路
を並列に接続し、該警報接点警報表示付きヒユーズF1
2に、半導体アレスタ13と警報接点警報表示付きヒユ
ーズF13を直列に接続した回路を並列に接続する如く
、半導体アレスタ1nと警報接点警報表示付きヒユーズ
Finを直列に接続した回路を並列に接続する迄のn段
構成にしである。
In FIG. 1, a semiconductor arrester 11 and a fuse filter with an alarm contact alarm display are connected to the signal line or power line to the device 100.
A circuit in which the semiconductor arrester 12 and a fuse F12 with an alarm contact alarm display are connected in series is connected in parallel to the fuse F1 with the alarm contact alarm display, and a circuit in which the semiconductor arrester 12 and the fuse F12 with the alarm contact alarm display are connected in series is connected in parallel. With fuse F1
2, until the circuit in which the semiconductor arrester 1n and the fuse Fin with alarm contact and alarm display are connected in series is connected in parallel, such as the circuit in which the semiconductor arrester 13 and the fuse F13 with alarm contact and alarm display are connected in parallel. It has an n-stage configuration.

従って、第1番目の過電圧サージに対しては、半導体ア
レスタ11が動作し、この半導体7レスタにサージ耐量
を越えるサージの流入があれば、半導体アレスタ11は
短絡障害となり、警報接点警報表示付きヒユーズFil
は溶断し、半導体アレスタI2が次の過電圧サージに対
し毀鮨するようになり、同じ原理によりn回迄のサージ
耐量を越えるサージ塩の、次々の過電圧サージに対して
゛  間断なく機能出来るようになり過電圧保護の信頼
性を向上出来る。
Therefore, in response to the first overvoltage surge, the semiconductor arrester 11 operates, and if a surge that exceeds the surge resistance flows into the semiconductor 7 resistor, the semiconductor arrester 11 will be short-circuited, and the fuse with alarm contact alarm display will be activated. Fil
fuses, and the semiconductor arrester I2 begins to fail against the next overvoltage surge. Based on the same principle, it can function without interruption against successive overvoltage surges of surge salt that exceeds the surge resistance up to n times. The reliability of overvoltage protection can be improved.

又警報接点警報表示付きヒユーズの溶断により警報接点
はオンとなるので、これを用い半導体アレスタの短絡障
害をすぐ検出出来るため、交換時間が短縮出来、更に過
電圧保護の信頼性を向上出来る。
Furthermore, since the alarm contact is turned on by blowing the fuse with the alarm contact alarm display, short-circuit failure of the semiconductor arrester can be immediately detected using this, so that replacement time can be shortened and the reliability of overvoltage protection can be improved.

第2図は本発明の他の実施例の過電圧保護回路の回路図
である。
FIG. 2 is a circuit diagram of an overvoltage protection circuit according to another embodiment of the present invention.

図中1〜nは半導体アレスタ、F1〜FnはP形ヒユー
ズの如き警報接点警報表示付きヒユーズ、f1〜fn−
1は夫々警報接点警報表示付きヒユーズlアリ鼾との警
報接点、10oは機器を示す。
In the figure, 1 to n are semiconductor arresters, F1 to Fn are fuses with alarm contacts such as P-type fuses, and f1 to fn-
1 indicates an alarm contact with a fuse with an alarm display, and 10o indicates a device.

第2図では、機器100への信号線又は電源線に、半導
体7レスタ1と警報接点警報表示付きヒユーズF1を直
列に接続した第1の回路、及び半導体アレスタ2と警報
接点警報表示付きヒユーズF2と該警報接点警報表示付
きヒユーズF1の警報接点f1とを直列に接続した第2
の回路、及び半導体アレスタ3と警報接点警報表示付き
ヒユーズF3と該警報接点警報表示付きヒユーズF2の
警報接点f2とを直列に接続した第3の回路、及び半導
体アレスタnと警報接点警報表示付きヒユーズFnと警
報接点警報表示付きヒユーズFn−1の警報接点fn−
1とを直列に接続した第nの回路を並列に接続するn段
構成にしである。
FIG. 2 shows a first circuit in which a semiconductor 7 arrester 1 and a fuse F1 with an alarm contact alarm display are connected in series to a signal line or a power supply line to the device 100, and a semiconductor arrester 2 and a fuse F2 with an alarm contact alarm display are connected in series. and the alarm contact f1 of the fuse F1 with alarm contact alarm display are connected in series.
and a third circuit in which the semiconductor arrester 3, the fuse F3 with an alarm contact alarm display, and the alarm contact f2 of the fuse F2 with the alarm contact alarm display are connected in series, and the semiconductor arrester n and the fuse with an alarm contact alarm display. Fn and alarm contact Alarm contact fn- of fuse Fn-1 with alarm display
This is an n-stage configuration in which an n-th circuit in which 1 and 1 are connected in series is connected in parallel.

従って、第1番目の過電圧サージに対しては、半導体ア
レスタ1が動作し、この半導体アレスタにサージ耐量を
越えるサージの流入があれば、半導体アレスタ1は短絡
障害となり、警報接点警報表示付きヒユーズF1は溶断
し、警報接点f1はオンとなり、半導体アレスタ2が次
の過電圧サージに対し機能するようになり、同じ原理で
、n回迄のサージ耐量を越えるサージ塩の、次々の過電
圧サージに対して間断なく機能出来るようになり過電圧
保護の信頼性を向上出来る。
Therefore, in response to the first overvoltage surge, the semiconductor arrester 1 operates, and if a surge exceeding the surge withstand capacity flows into this semiconductor arrester, the semiconductor arrester 1 becomes a short-circuit failure, and the fuse F1 with alarm contact alarm display is activated. fuses, the alarm contact f1 turns on, and the semiconductor arrester 2 comes to function against the next overvoltage surge. Based on the same principle, it can be used against successive overvoltage surges of surge salt exceeding the surge resistance up to n times. It can function without interruption, improving the reliability of overvoltage protection.

又警報接点警報表示付きヒユーズの溶断による警報表示
により、半導体アレスタの短絡障害をすぐ表示出来るた
め交換時間が短くなり、更に過電圧保護の信幀性を向上
出来る。
In addition, the alarm display caused by the melting of the fuse with the alarm contact alarm display can immediately indicate a short-circuit failure of the semiconductor arrester, thereby shortening the replacement time and further improving the reliability of overvoltage protection.

〔発明の効果〕〔Effect of the invention〕

以上詳細に説明せる如く本発明によれば、n回迄のサー
ジ耐量を越えるサージ迄の、次々の過電圧サージに対し
て間断なく機能出来るようになり過電圧保護の信頼性を
向上出来又警報接点警報表示付きヒユーズの溶断による
警報表示又は警報接点により、半導体アレスタの短絡障
害をすぐ検出出来、交換時間が短(なり、更に過電圧保
護の信頼性を向上出来る効果がある。
As explained in detail above, according to the present invention, it is possible to function continuously against successive overvoltage surges up to n times of surges exceeding the surge withstand capacity, improving the reliability of overvoltage protection, and alarm contact alarm. By displaying an alarm by blowing a fuse with an indicator or by using an alarm contact, a short-circuit failure of a semiconductor arrester can be immediately detected, the replacement time can be shortened, and the reliability of overvoltage protection can be further improved.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明8★施例の過電圧保護回路の回路図、 くシ 第2図は本発明の他の実施例の過電圧保護回路の回路図
、 第3図は、従来例の過電圧保護回路の回路図である。 図において、 1〜n、11〜In、20は半導体アレスタ、F1〜F
n、Fil〜Finは警報接点警報表示付きヒユーズ、 f1〜fn−1は警報接点−−表示(H区!fずH〕丑
に−H橿i透紅 100は機器、 Rは抵抗を示す。 オ→茫旧月一方巳1にトリ阪電しイネ事駈圀吋シの回に
i図第 1 ffi gb 2 図
Figure 1 is a circuit diagram of an overvoltage protection circuit according to an 8★ embodiment of the present invention, Figure 2 is a circuit diagram of an overvoltage protection circuit according to another embodiment of the invention, and Figure 3 is a conventional overvoltage protection circuit. FIG. In the figure, 1 to n, 11 to In, 20 are semiconductor arresters, F1 to F
n, Fil~Fin are fuses with alarm contact alarm display, f1~fn-1 are alarm contact--display (H ward! O → Tori Handen on the first day of the first month of the month, and the second time of the rice event, Figure i Figure 1 ffi gb 2 Figure

Claims (1)

【特許請求の範囲】 1、過電圧から保護すべき装置に、 第1の半導体アレスタと第1の警報接点付きヒューズを
直列に接続した回路を電源線又は信号線に並列に接続し
、 該第1の警報接点付きヒューズに、第2の半導体アレス
タと第2の警報接点付きヒューズを直列に接続した回路
を並列に接続する如く、 第n−1の警報接点付きヒューズに、第nの半導体アレ
スタと第nの警報接点付きヒューズを直列に接続した回
路を並列に接続し、 半導体アレスタをn段構成としたことを特徴とする過電
圧保護回路。 2、第1の半導体アレスタと第1の警報接点警報表示付
きヒューズを直列に接続した第1の回路、及び第2の半
導体アレスタと第2の警報接点警報表示付きヒューズと
該第1の警報接点警報表示付きヒューズの警報接点とを
直列に接続した第2の回路、 及び第nの半導体アレスタと第nの警報接点警報表示付
きヒューズと第n−1の警報接点警報表示付きヒューズ
の警報接点とを直列に接続した第nの回路の合計n個の
回路を、 過電圧から保護すべき装置に並列に接続したことを特徴
とする過電圧保護回路。
[Claims] 1. In a device to be protected from overvoltage, a circuit in which a first semiconductor arrester and a first fuse with an alarm contact are connected in series is connected in parallel to a power supply line or a signal line, and the first In this way, a circuit in which a second semiconductor arrester and a second fuse with alarm contacts are connected in series is connected in parallel to the fuse with alarm contacts of . An overvoltage protection circuit characterized in that a circuit in which a fuse with an n-th alarm contact is connected in series is connected in parallel to form an n-stage semiconductor arrester. 2. A first circuit in which a first semiconductor arrester, a first alarm contact, a fuse with an alarm display are connected in series, and a second semiconductor arrester, a second alarm contact, a fuse with an alarm display, and the first alarm contact. a second circuit in which an alarm contact of a fuse with an alarm display is connected in series; An overvoltage protection circuit characterized in that a total of n circuits, including an nth circuit connected in series, are connected in parallel to a device to be protected from overvoltage.
JP8681385A 1985-04-23 1985-04-23 Overvoltage protection circuit Pending JPS61247225A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8681385A JPS61247225A (en) 1985-04-23 1985-04-23 Overvoltage protection circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8681385A JPS61247225A (en) 1985-04-23 1985-04-23 Overvoltage protection circuit

Publications (1)

Publication Number Publication Date
JPS61247225A true JPS61247225A (en) 1986-11-04

Family

ID=13897248

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8681385A Pending JPS61247225A (en) 1985-04-23 1985-04-23 Overvoltage protection circuit

Country Status (1)

Country Link
JP (1) JPS61247225A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006325288A (en) * 2005-05-17 2006-11-30 Thor:Kk Thunder surge protector
JP2011205796A (en) * 2010-03-25 2011-10-13 Nec Infrontia Corp Failure detection circuit for overvoltage protection elements and subscriber circuit

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006325288A (en) * 2005-05-17 2006-11-30 Thor:Kk Thunder surge protector
JP2011205796A (en) * 2010-03-25 2011-10-13 Nec Infrontia Corp Failure detection circuit for overvoltage protection elements and subscriber circuit

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