JPH01209921A - Protecting circuit for firing lamp - Google Patents

Protecting circuit for firing lamp

Info

Publication number
JPH01209921A
JPH01209921A JP3439388A JP3439388A JPH01209921A JP H01209921 A JPH01209921 A JP H01209921A JP 3439388 A JP3439388 A JP 3439388A JP 3439388 A JP3439388 A JP 3439388A JP H01209921 A JPH01209921 A JP H01209921A
Authority
JP
Japan
Prior art keywords
lamp
thermistor
current
normally open
lighting
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
JP3439388A
Other languages
Japanese (ja)
Inventor
Osamu Fukushima
修 福島
Kanji Tokuda
莞司 徳田
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.)
Fujifilm Holdings Corp
Original Assignee
Fuji Photo Film Co 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 Fuji Photo Film Co Ltd filed Critical Fuji Photo Film Co Ltd
Priority to JP3439388A priority Critical patent/JPH01209921A/en
Publication of JPH01209921A publication Critical patent/JPH01209921A/en
Pending legal-status Critical Current

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Abstract

PURPOSE:To protect a lamp against a rush current and to suppress the deterioration of a thermistor by closing a normally open contact provided in parallel with the thermistor connected in series with the lamp after a predetermined time is elapsed from the time of initiating to fire the lamp. CONSTITUTION:A fuse 16, a lamp 12 and a thermistor 18 are connected in series with an AC power source 14A. Bypass circuits 22, 23 are composed through a normally open contact 20 at the thermistor 18. The contact 20 forms a relay circuit 24 to be energized by a coil 26. When the lamp 12 is fired, a small current flows from the power source 14A by the negative resistance of the thermistor 18 to suppress the rush current of the lamp 12, and a small current also flows to the coil 26. The current increases upon rising of the temperature of the thermistor 12. When the current of the coil 26 rises at a predetermined value or more, the contact 20 is closed to short-circuit the thermistor 18, thereby supplying a predetermined current to the lamp 12. Thus, the lamp 12 is protected against the rush current, thereby preventing the thermistor 18 from consuming.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明はランプの点灯開始時の突入電流を低減するラン
プ点灯用保護回路に関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lamp lighting protection circuit that reduces inrush current at the start of lamp lighting.

〔従来技術〕[Prior art]

一般にランプ、例えばハロゲンランプのフィラメントは
、その温度と抵抗値とが比例関係にあり、消灯状態では
抵抗値が低くこの状態で点灯を開始すると、第6図に示
される如く、点灯する瞬間に通常の電流値に比べて14
〜15倍の電流(突入電流)が流れることになる。この
初期の大電流によってフィラメントが切れ易いことはよ
く知られている。なお、点灯が継続されると、温度上昇
に伴って抵抗値が高くなり、定格の電流値となり安定す
る。
Generally, the filament of a lamp, for example a halogen lamp, has a proportional relationship between its temperature and its resistance value, and when it is off, the resistance value is low. 14 compared to the current value of
~15 times the current (rush current) will flow. It is well known that the filament is likely to break due to this initial large current. Note that if the lighting continues, the resistance value increases as the temperature rises, and the current value becomes stable at the rated value.

ここで、点灯開始時の突入電流を低減するため、ハロゲ
ンランプと直列にサーミスタを接続することが考えられ
ている。すなわち、サーミスタは温度と抵抗値とが反比
例の関係にあり、点灯開始時には抵抗値が高いので、第
7図に示される如く、電流をあまり流さず、この結果突
入電流を低減できる。また、点灯状態が継続され温度が
上昇するに従い抵抗値が下がり、ハロゲンランプへ定格
の電流を流すことができる。これにより、ノ\ロゲンラ
ンプの寿命をのばすことがきる。なお、現在電球とソケ
ットとの間に挿入するのみで、前記効果を得ることがで
きるものが市販されている(CIRTIFIED BN
ERGY SYSTBMS lNC1(米国)社製「サ
ーミスタボタン(商品名)」)。これによれば、組み付
けも容易で既存の装置に改良を加えることなく、効果を
あげることができる。
Here, in order to reduce the rush current at the start of lighting, it has been considered to connect a thermistor in series with the halogen lamp. That is, the temperature and resistance value of the thermistor are inversely proportional, and the resistance value is high at the start of lighting, so as shown in FIG. 7, not much current flows, and as a result, the rush current can be reduced. Further, as the lighting state continues and the temperature rises, the resistance value decreases, allowing the rated current to flow through the halogen lamp. This can extend the life of the halogen lamp. Currently, there is a product on the market that can achieve the above effect by simply inserting it between a light bulb and a socket (CIRTIFIED BN).
"Thermistor button (product name)" manufactured by ERGY SYSTBMS INC1 (USA). According to this, it is easy to assemble and the effect can be achieved without making any improvements to the existing device.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

しかしながら、このような回路構成では、ハロゲンラン
プ点灯中はサーミスタ(市販のサーミスタボタンも含む
)に常に電流が流れており、ハロゲンランプの寿命は長
くなるものの、サーミスタ自体が熱により破損すること
が考えられ、このサーミスタをも保護する必要がある。
However, with this type of circuit configuration, current always flows through the thermistor (including commercially available thermistor buttons) while the halogen lamp is on, and although the life of the halogen lamp is extended, the thermistor itself may be damaged by heat. This thermistor also needs to be protected.

本発明は上記事実を考慮し、ランプとこのランプを保護
するサーミスタとの両方を保護し、回路全体の寿命を延
ばすことができるランプ点灯用保護回路を得ることが目
的である。
In consideration of the above-mentioned facts, the present invention aims to provide a lamp lighting protection circuit that can protect both the lamp and the thermistor that protects the lamp, and extend the life of the entire circuit.

〔課題を解決するための手段〕[Means to solve the problem]

本発明に係るランプ点灯用保護回路は、温度上昇に応じ
て抵抗値が低くなるサーミスタを備えランプに対して直
列に接続されてランプの点灯開始時の突入電流を低減す
るランプ点灯用保護回路であって、前記サーミスタに対
して並列接続された常開接点と、前記常開接点をランプ
点灯開始時から所定時間経過後に閉状態とする導通手段
と、を有している。
The lamp lighting protection circuit according to the present invention is a lamp lighting protection circuit that includes a thermistor whose resistance value decreases as the temperature rises and is connected in series with the lamp to reduce the rush current when the lamp starts lighting. The lamp includes a normally open contact connected in parallel to the thermistor, and conduction means for closing the normally open contact after a predetermined period of time has elapsed from the start of lighting the lamp.

〔作用〕[Effect]

ランプの点灯を開始状態では温度が低いため、サーミス
タの抵抗値が高い。これにより、ランプへの突入電流が
低減される。ランプ点灯後は温度上昇に応じてサーミス
タの抵抗値が下がりランプへ流れる電流が徐々に多くな
り定格電流へと近づく。
When the lamp starts lighting, the temperature is low, so the resistance value of the thermistor is high. This reduces the rush current into the lamp. After the lamp is turned on, the resistance value of the thermistor decreases as the temperature rises, and the current flowing into the lamp gradually increases until it approaches the rated current.

ここで、本発明ではランプの点灯開始から所定時間後に
導通手段によって常開接点を閉状態とし、バイパス回路
を導通させる。これにより、サーミスタの両端は短絡さ
れ、サーミスタへは電流は流れず、バイパスして電流は
流れるので、ランプの点灯継続状態でのサーミスタの熱
による破損等を防止することができる。
Here, in the present invention, the normally open contact is closed by the conduction means after a predetermined period of time from the start of lighting of the lamp, and the bypass circuit is made conductive. As a result, both ends of the thermistor are short-circuited, and no current flows to the thermistor, but the current flows in a bypass manner, so that damage to the thermistor due to heat while the lamp continues to be lit can be prevented.

このように、本発明ではサーミスタによってランプを保
護するのみならず、常開接点の導通状態で電流をバイパ
スさせるので、サーミスタ自体をも保護することができ
、回路全体の寿命を大幅に延ばすことができる。
In this way, in the present invention, the thermistor not only protects the lamp, but also bypasses the current when the normally open contact is conductive, so the thermistor itself can also be protected, and the life of the entire circuit can be significantly extended. can.

〔実施例〕〔Example〕

第1図には本実施例に係るランプ点灯用保護回路10が
示されている。。
FIG. 1 shows a lamp lighting protection circuit 10 according to this embodiment. .

本実施例ではランプとしてハロゲンランプ12が適用さ
れてふり、交流電源線14の中間部に接続されている。
In this embodiment, a halogen lamp 12 is used as the lamp, and is connected to an intermediate portion of an AC power line 14.

また、この交流電源線14にはヒユーズ16とサーミス
タ18とが直列に接続されいる。サーミスタ18は温度
と抵抗とが反比例となる特性を有する素子であり、ハロ
ゲンランプ12の消灯状態ではその抵抗値は高い値とな
っている。従って、この状態で交流電源線14に電流が
流れると、サーミスタ18の抵抗によりハロゲンランプ
12には電流があまり流れず、第7図に示される如く、
突入電流を低減することができる。
Further, a fuse 16 and a thermistor 18 are connected in series to this AC power line 14. The thermistor 18 is an element having a property that temperature and resistance are inversely proportional, and its resistance value is high when the halogen lamp 12 is off. Therefore, when current flows through the AC power line 14 in this state, the resistance of the thermistor 18 prevents much current from flowing through the halogen lamp 12, as shown in FIG.
Inrush current can be reduced.

サーミスタ18の両端は常開接点20を介してバイパス
線22.23によって接続されている(バイパス回路)
。この常開接点20はリレー回路24の一部を構成して
おり、この常開接点2・0を磁力で閉状態とする前記常
開接点20と共にリレー回路24を構成するコイル26
が常開接点20に対応して配置されている。コイル26
の両端は、交流電源線14の一方の入力端子14Aとヒ
ユーズ16との間、ハロゲンランプ12とサーミスタ1
8との間にそれぞれ接続されている。
Both ends of the thermistor 18 are connected by bypass wires 22 and 23 via a normally open contact 20 (bypass circuit)
. This normally open contact 20 constitutes a part of a relay circuit 24, and the coil 26 which constitutes the relay circuit 24 together with the normally open contact 20 which closes this normally open contact 2.0 by magnetic force.
are arranged corresponding to the normally open contacts 20. coil 26
The two ends of the halogen lamp 12 and the thermistor 1 are connected between one input terminal 14A of the AC power line 14 and the fuse 16.
8, respectively.

従って、交流電源線14に電流が流れるとその一部がコ
イル26へも流れ、磁力が生じて常開接点20を閉状態
とすることができるようになっている。なお、この場合
交流はコイル26へは流れにクク、かつサーミスタ18
によりハロゲンランプ120点灯初期状態では電流値が
小さいので、磁力を生じさせるための電流値(第2図に
示すリレー作動電流値)に至るまでに若干の立ち上がり
時間が必要とされ、この時間分(第2図及び第3図時間
t、参照)常開接点20の閉動作が遅れることになる。
Therefore, when a current flows through the AC power line 14, a portion of the current also flows to the coil 26, generating magnetic force, which allows the normally open contact 20 to be closed. In this case, the alternating current flows to the coil 26, and the thermistor 18
Since the current value is small in the initial state of lighting of the halogen lamp 120, a slight rise time is required until the current value for generating magnetic force (the relay operating current value shown in Fig. 2) is reached, and this time ( (See time t in FIGS. 2 and 3) The closing operation of the normally open contact 20 is delayed.

ここで、常開接点20が閉状態とされると、サーミスタ
18の両端のバイパス線22.23が導通状態とされ、
サーミスタ18へは電流が流れなくなることになる。な
お、この遅れ時間は前記突入電流の最大値を越えた後と
されており、この結果ハロゲンランプ12を流れる電流
値は第3図の実線で示されるような特性となる。
Here, when the normally open contact 20 is brought into a closed state, the bypass wires 22 and 23 at both ends of the thermistor 18 are brought into a conductive state,
Current will no longer flow to the thermistor 18. Note that this delay time is set after the inrush current exceeds the maximum value, and as a result, the value of the current flowing through the halogen lamp 12 has characteristics as shown by the solid line in FIG.

以下に本実施例の作用を説明する。The operation of this embodiment will be explained below.

ハロゲンランプ12の消灯状態から交流電源線14へ電
流が流れると、ハロランプ12は点灯を開始するが、サ
ーミスタ18の温度が低いためこのサーミスタ18の抵
抗値が高く、この結果ハロゲンランプ12へ流れる電流
値も小さい。ハロゲンランプ12の点灯状態が継続され
ると、サーミスタ18の温度が徐々に上がり、サーミス
タ18の特性によりサーミスタ18自体の抵抗値が徐々
に下がってくる。この抵抗値の低下に応じてハロゲンラ
ンプ12へ流れる電流値が増加する。
When a current flows from the halogen lamp 12 to the AC power line 14 when the halogen lamp 12 is turned off, the halogen lamp 12 starts lighting up, but since the temperature of the thermistor 18 is low, the resistance value of the thermistor 18 is high, and as a result, the current flows to the halogen lamp 12. The value is also small. When the halogen lamp 12 continues to be lit, the temperature of the thermistor 18 gradually increases, and the resistance value of the thermistor 18 itself gradually decreases due to the characteristics of the thermistor 18. As the resistance value decreases, the current value flowing to the halogen lamp 12 increases.

ここで、本実施例では、交流電源線14へ電流を流すと
コイル26にも電流が流れる。しかし、ハロゲンランプ
点灯初期状態ではこのコイル26へ流れる電流値は小さ
く、常開接点20を閉状態とするための磁力はない。こ
こで、所定の時間t、が経過すると、コイル26へ流れ
る電流値がリレー作動電流値を越え、常開接点20は閉
状態となり、バイパス線22.23が導通状態とされる
。バイパス線22.23が導通状態とされると、電流は
このバイパス線22.23を通るので、サーミスタ18
へは電流は流れなくなる。これにより、ハロゲンランプ
120点灯状態で常時サーミスタ18へ電流を流すこと
が防止され、サーミスタ18を保護することができる。
Here, in this embodiment, when a current is passed through the AC power line 14, a current also flows through the coil 26. However, in the initial state of lighting the halogen lamp, the current value flowing through the coil 26 is small, and there is no magnetic force to close the normally open contact 20. Here, when a predetermined time t has elapsed, the current value flowing to the coil 26 exceeds the relay operating current value, the normally open contact 20 is closed, and the bypass wires 22 and 23 are brought into a conductive state. When the bypass line 22.23 is made conductive, current passes through the bypass line 22.23, so the thermistor 18
Current will no longer flow to. This prevents current from constantly flowing to the thermistor 18 while the halogen lamp 120 is on, and the thermistor 18 can be protected.

また、このサーミスタ18の保護開始時(時間1.経過
時)、サーミスタ18が取り付けられていない場合に生
じる突入電流(第6図参照)の最大値を越えており、ハ
ロゲンランプ12へ流れる電流値もさほど高くなく、ハ
ロゲンランプ12も従来どおり保護することができる。
Furthermore, at the start of protection of this thermistor 18 (after time 1), the maximum value of the inrush current (see Figure 6) that would occur if the thermistor 18 is not installed is exceeded, and the current flowing to the halogen lamp 12 exceeds the maximum value. The cost is not so high, and the halogen lamp 12 can also be protected as before.

このように、本第実施例ではハロゲンランプ12への突
入電流を低減することができると共に突入電流が発生す
る時期を越えた場合には、サーミスタ18へ流れる電流
も阻止するようにしたので、ハロゲンランプ点灯用の回
路全体の寿命を延ばすことができる。
In this way, in this embodiment, the inrush current to the halogen lamp 12 can be reduced, and when the inrush current generation period is exceeded, the current flowing to the thermistor 18 is also blocked. The life of the entire lamp lighting circuit can be extended.

な右、本実施例では、電源に交流を適用したが、第4図
に示される如く、電源に直流を適用する場合も同様の効
果を得ることができる。但し、直流電源の場合は、コイ
ル26へ電流が流れ易いため、直列接続された抵抗28
及びコンデンサ30をコイル26の両端に並列接続し、
コンデンサ30の電荷時間を利用してコイル26へ流れ
る電流値を制御し、第5図に示される如く、リレー作動
電流までの立ち上がり時間を遅らせる必要がある。すな
わち、第5図に示される如くハロゲンランプ点灯初期で
はコンデンサ30とコイル26との両方に電流が分散さ
れ、コンデンサ30の電荷が終了すると、全電流がコイ
ル26へ流れ前記リレ、−作動電流を越えることになる
。   − また、本実施例では、バイパス回路導通手段と常開接点
とを組み合わせてリレー回路24を構成し、適用したが
、バイパス回路導通手段にタイマを適用し、このタイマ
で常開接点を導通遮断させる時期を得るようにしてもよ
い。
Although, in this embodiment, an alternating current is applied to the power source, the same effect can be obtained when a direct current is applied to the power source as shown in FIG. However, in the case of a DC power supply, current easily flows to the coil 26, so the resistor 28 connected in series
and a capacitor 30 is connected in parallel to both ends of the coil 26,
It is necessary to control the current value flowing to the coil 26 using the charging time of the capacitor 30, and delay the rise time to the relay operating current, as shown in FIG. That is, as shown in FIG. 5, at the beginning of lighting the halogen lamp, the current is dispersed in both the capacitor 30 and the coil 26, and when the capacitor 30 is fully charged, the entire current flows to the coil 26, reducing the operating current of the relay. I will cross it. - In addition, in this embodiment, the relay circuit 24 is configured and applied by combining the bypass circuit conduction means and the normally open contact, but a timer is applied to the bypass circuit conduction means, and this timer interrupts the conduction of the normally open contact. You may also try to find a time to do so.

〔発明の効果〕〔Effect of the invention〕

以上説明した如く本発明に係るランプ点灯用保護回路は
、ランプとこのランプを保護するサーミスタとの両方を
保護し、回路全体の寿命を延ばすことができるという優
れた効果を有する。
As explained above, the lamp lighting protection circuit according to the present invention has the excellent effect of protecting both the lamp and the thermistor that protects the lamp, and extending the life of the entire circuit.

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

第1図は本実施例に係るハロゲンランプ点灯用保護回路
の回路図、第2図はコイル電流の特性図、第3図はハロ
ゲンランプを流れる電流の特性図、第4図は電源に直流
を適用した場合の回路図、第5図は第4図に示す回路で
のコイル電流の特性図、第6図はサーミスタの取り付け
られていない場合のハロゲンランプを流れる電流の特性
図、第7図はサーミスタを取り付けた場合のハロゲンラ
ンプを流れる電流の特性図である。 10・・・ランプ点灯用保護回路、 12・・・ハロゲンランプ、 18・・・サーミスタ、 20・・・常開接点、 22.23・・・バイパス線、 24・・・リレー回路、 26・・・コイル、 30・・・コンデンサ。
Figure 1 is a circuit diagram of the protective circuit for lighting a halogen lamp according to this embodiment, Figure 2 is a characteristic diagram of the coil current, Figure 3 is a characteristic diagram of the current flowing through the halogen lamp, and Figure 4 is a diagram of the DC power supply. Figure 5 is the characteristic diagram of the coil current in the circuit shown in Figure 4, Figure 6 is the characteristic diagram of the current flowing through the halogen lamp when the thermistor is not installed, Figure 7 is the circuit diagram when the application is applied. It is a characteristic diagram of the electric current which flows through a halogen lamp when a thermistor is attached. DESCRIPTION OF SYMBOLS 10... Lamp lighting protection circuit, 12... Halogen lamp, 18... Thermistor, 20... Normally open contact, 22.23... Bypass line, 24... Relay circuit, 26...・Coil, 30... Capacitor.

Claims (1)

【特許請求の範囲】[Claims] (1)温度上昇に応じて抵抗値が低くなるサーミスタを
備えランプに対して直列に接続されてランプの点灯開始
時の突入電流を低減するランプ点灯用保護回路であって
、前記サーミスタに対して並列接続された常開接点と、
前記常開接点をランプ点灯開始時から所定時間経過後に
閉状態とする導通手段と、を有するランプ点灯用保護回
路。
(1) A protection circuit for lamp lighting that is equipped with a thermistor whose resistance value decreases as the temperature rises and is connected in series to the lamp to reduce inrush current when the lamp starts lighting; normally open contacts connected in parallel;
A protection circuit for lighting a lamp, comprising: a conduction means for closing the normally open contact after a predetermined period of time has elapsed from the start of lighting the lamp.
JP3439388A 1988-02-17 1988-02-17 Protecting circuit for firing lamp Pending JPH01209921A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3439388A JPH01209921A (en) 1988-02-17 1988-02-17 Protecting circuit for firing lamp

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3439388A JPH01209921A (en) 1988-02-17 1988-02-17 Protecting circuit for firing lamp

Publications (1)

Publication Number Publication Date
JPH01209921A true JPH01209921A (en) 1989-08-23

Family

ID=12412932

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3439388A Pending JPH01209921A (en) 1988-02-17 1988-02-17 Protecting circuit for firing lamp

Country Status (1)

Country Link
JP (1) JPH01209921A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02140559U (en) * 1989-04-28 1990-11-26
JPH04190618A (en) * 1990-11-21 1992-07-09 Mitsubishi Electric Corp Plant protective apparatus
JPH04229019A (en) * 1990-09-04 1992-08-18 Internatl Business Mach Corp <Ibm> Rectifier for limiting current and current sensing circuit

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56110435A (en) * 1980-02-04 1981-09-01 Fujitsu Ltd Rush current preventing circuit
JPS6025341B2 (en) * 1976-05-20 1985-06-18 新日本製鐵株式会社 Automatic warehouse for coils
JPS617290B2 (en) * 1980-12-17 1986-03-05 Kyoritsu Kk

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6025341B2 (en) * 1976-05-20 1985-06-18 新日本製鐵株式会社 Automatic warehouse for coils
JPS56110435A (en) * 1980-02-04 1981-09-01 Fujitsu Ltd Rush current preventing circuit
JPS617290B2 (en) * 1980-12-17 1986-03-05 Kyoritsu Kk

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02140559U (en) * 1989-04-28 1990-11-26
JPH04229019A (en) * 1990-09-04 1992-08-18 Internatl Business Mach Corp <Ibm> Rectifier for limiting current and current sensing circuit
JPH04190618A (en) * 1990-11-21 1992-07-09 Mitsubishi Electric Corp Plant protective apparatus

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