JPH04351422A - Open circuit detector for secondary circuit of current transformer - Google Patents
Open circuit detector for secondary circuit of current transformerInfo
- Publication number
- JPH04351422A JPH04351422A JP12598491A JP12598491A JPH04351422A JP H04351422 A JPH04351422 A JP H04351422A JP 12598491 A JP12598491 A JP 12598491A JP 12598491 A JP12598491 A JP 12598491A JP H04351422 A JPH04351422 A JP H04351422A
- Authority
- JP
- Japan
- Prior art keywords
- current transformer
- light
- circuit
- secondary circuit
- open
- 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
Links
- 238000001514 detection method Methods 0.000 claims description 25
- 230000001681 protective effect Effects 0.000 abstract description 8
- 238000012544 monitoring process Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 4
- 230000015556 catabolic process Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000020169 heat generation Effects 0.000 description 2
- 230000004913 activation Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
Description
【０００１】 ［発明の目的］0001 [Purpose of the invention]
【０００２】0002
【産業上の利用分野】本発明は、変流器の２次出力端に
負荷装置を結合してなる変流器の２次回路において、何
等かの理由によりこの２次回路が開放された場合に、こ
れを検出すると共に変流器を含めた２次回路の保護及び
負荷装置の状態を知ることのできる装置に関する。[Industrial Application Field] The present invention is applicable to a secondary circuit of a current transformer in which a load device is connected to the secondary output terminal of the current transformer, and when the secondary circuit is opened for some reason. The present invention also relates to a device that can detect this, protect a secondary circuit including a current transformer, and know the status of a load device.
【０００３】0003
【従来の技術】一般に変流器の２次回路は低インピーダ
ンスに形成されている。従って１次側通電中において２
次回路が開放されると、その開放端には高電圧が生じて
変流器のみならず２次回路の絶縁破壊を招く可能性があ
る。従って従来は変流器２次回路の不測の開放を検出す
るために、変流器の２次回路に監視用の補助変流器等を
挿入して、２次回路に流れる電流値を監視しており、こ
れが所定値以下に減少したことを判別回路で判断して、
変流器の２次回路が開放されたことを知る方法や、負荷
装置が発熱部品である場合には、２次回路が開放された
ことにより負荷装置への通電が消滅し、このために発熱
がなくなり負荷装置の温度が低下することを予め設置し
てあるバイメタル等のサーマルセンサで検知して、２次
回路開放を検出する方法が採用されていた。2. Description of the Related Art Generally, the secondary circuit of a current transformer is formed to have low impedance. Therefore, when the primary side is energized, 2
If the next circuit is opened, a high voltage will be generated at the open end, which may lead to dielectric breakdown not only in the current transformer but also in the secondary circuit. Therefore, in the past, in order to detect an unexpected open circuit in the secondary circuit of a current transformer, an auxiliary current transformer for monitoring was inserted into the secondary circuit of the current transformer to monitor the current value flowing in the secondary circuit. The determination circuit determines that this has decreased below a predetermined value, and
How to know when the secondary circuit of a current transformer is open, or if the load device is a heat-generating component, the current to the load device disappears when the secondary circuit is opened, and this causes heat generation. A method has been adopted in which an open secondary circuit is detected by detecting a decrease in the temperature of the load device due to the loss of heat with a thermal sensor such as a bimetal installed in advance.
【０００４】0004
【発明が解決しようとする課題】変流器の２次回路に流
れる電流値を測定する方法では、変流器の１次電流が大
幅に減少したり、または消滅した場合においても２次回
路の電流が大きく減少するので、これを２次回路の開放
と誤判断したり、外部からの雷ノイズ等の侵入に際して
も作動し易い欠点がある。また負荷装置の温度を検知す
る方法では、部品の発熱と熱伝導を利用することから応
答性が悪く、かつ周囲温度の影響や用途が限定される等
の問題があった。[Problem to be Solved by the Invention] In the method of measuring the value of the current flowing in the secondary circuit of a current transformer, even if the primary current of the current transformer significantly decreases or disappears, the value of the current flowing in the secondary circuit remains unchanged. Since the current decreases significantly, there is a drawback that this is easily misjudged as an open circuit in the secondary circuit, or it is easy to operate when lightning noise or the like from the outside enters. In addition, the method of detecting the temperature of a load device uses heat generation and heat conduction of components, so there are problems such as poor responsiveness, influence of ambient temperature, and limited applications.
【０００５】本発明の目的は簡易な構成の検出装置によ
り、変流器２次回路の開放時に生じる高電圧を瞬時に検
出して、誤動作がなく変流器の２次回路の保護や負荷装
置の状態監視が容易な変流器２次回路の開放検出装置を
提供することにある。
［発明の構成］An object of the present invention is to instantly detect the high voltage generated when the secondary circuit of a current transformer is opened using a detection device with a simple configuration, thereby preventing malfunction and protecting the secondary circuit of the current transformer and the load device. An object of the present invention is to provide an open circuit detection device for a current transformer secondary circuit, which allows easy monitoring of the state of the current transformer. [Structure of the invention]
【０００６】[0006]
【課題を解決するための手段】変流器の２次出力端に接
続して、所定電圧値を超過した時に放電するアレスタと
このアレスタの放電電流を制御する抵抗器と前記アレス
タの放電電流により発光する発光部及びこの発光部の発
光を検知して外部に信号を出力する受光部からなるフォ
トカプラを直列に接続すると共に前記フォトカプラの発
光部と並列に発光部保護用素子を接続した開放検出装置
を設ける。[Means for Solving the Problems] An arrester connected to the secondary output terminal of a current transformer discharges when a predetermined voltage value is exceeded, a resistor that controls the discharge current of this arrester, and a resistor that controls the discharge current of the arrester. A photocoupler consisting of a light-emitting part that emits light and a light-receiving part that detects the light emission from the light-emitting part and outputs a signal to the outside is connected in series, and a light-emitting part protection element is connected in parallel to the light-emitting part of the photocoupler. Provide a detection device.
【０００７】[0007]
【作用】変流器の２次回路が開放されると、その開放端
に高電圧が発生する。この高電圧がアレスタの所定電圧
値を超過すると、アレスタは放電して放電電流が流れる
。この放電電流は抵抗器により制限されると共に、フォ
トカプラの発光部に流れてフォトカプラから発光にとも
なう信号が出力される。この信号は変流器２次回路の開
放信号であり、また負荷装置が灯火にあっては、その灯
火の断芯信号でもある。[Operation] When the secondary circuit of the current transformer is opened, a high voltage is generated at the open end. When this high voltage exceeds a predetermined voltage value of the arrester, the arrester is discharged and a discharge current flows. This discharge current is limited by a resistor, flows to the light emitting part of the photocoupler, and a signal accompanying the light emission is output from the photocoupler. This signal is an open signal for the current transformer secondary circuit, and if the load device is a light, it is also a break signal for the light.
【０００８】[0008]
【実施例】本発明の一実施例を図面を参照して説明する
。図１は灯火点灯装置に採用した場合のブロック構成図
で、１次側に交流電源１を接続した変流器２と、この変
流器２の２次側の出力端子２ａ間に負荷装置である灯火
（ランプ）３を接続して２次回路を形成している。開放
検出装置４は、所定電圧値を超過した時に放電するアレ
スタ５と、このアレスタ５が放電した時にこの放電電流
を制御する抵抗器６と、放電電流を検出するダイオード
７を直列にして接続すると共に、このダイオード７と並
列に接続して共に放電電流の検出をする前記放電電流に
より発光する発光部及びこの発光部の発光を検知して外
部に信号を出力する受光部からなるフォトカプラ８で構
成して、前記変流器２の２次側の端子２ａ間に接続する
。DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Figure 1 is a block configuration diagram when the device is used in a lamp lighting device. A certain light (lamp) 3 is connected to form a secondary circuit. The open detection device 4 connects in series an arrester 5 that discharges when a predetermined voltage value is exceeded, a resistor 6 that controls the discharge current when the arrester 5 discharges, and a diode 7 that detects the discharge current. In addition, a photocoupler 8 includes a light emitting part that is connected in parallel with the diode 7 and emits light based on the discharge current and detects the discharge current, and a light receiving part that detects the light emitted from the light emitting part and outputs a signal to the outside. and is connected between the terminals 2a on the secondary side of the current transformer 2.
【０００９】また前記開放検出装置４の出力から２次回
路を保護する装置として、前記変流器２の２次側の出力
端子２ａ間に接続した保護接点１０と、フォトカプラ８
の出力信号を入力し、その出力信号の発信回数等を確認
して当該２次回路の開放信号９を発すると共に、前記保
護接点１０を作動させる制御装置１１を設けている。な
お前記ダイオード７はフォトカプラ８発光部と逆極性に
接続して発光部の保護も兼ねる。Further, as a device for protecting the secondary circuit from the output of the open detection device 4, a protective contact 10 connected between the output terminals 2a on the secondary side of the current transformer 2 and a photocoupler 8 are used.
A control device 11 is provided which inputs the output signal of , checks the number of times the output signal is transmitted, etc., issues an open signal 9 for the secondary circuit, and operates the protective contact 10 . Note that the diode 7 is connected with the opposite polarity to the light emitting section of the photocoupler 8 and also serves to protect the light emitting section.
【００１０】次ぎに上記構成による作用について説明す
る。正常時においては、交流電源１より変流器２を介し
て伝達された電力は、２次側の出力端子２ａを介して負
荷装置である灯火３に供給されて灯火３を点灯する。こ
の時、開放検出装置４には図２の開放検出装置の作動特
性図で示す、点２０におけるように変流器２次側の出力
端子２ａ間には正規値の電圧３０と波形が発生し、灯火
３には２次回路の電流３１が流れる。このような正常時
における電圧３０の大きさは、開放検出装置４内のアレ
スタ５に定められた放電開始電圧より低いためアレスタ
５は放電せず、フォトカプラ８発光部及びダイオード７
には電流が流れないので開放検出装置４は作動しない。
よって制御装置１１からも保護接点１０の作動と開放信
号９の出力は行われず保護接点１０は開いている。Next, the operation of the above structure will be explained. Under normal conditions, power transmitted from the AC power supply 1 via the current transformer 2 is supplied to the light 3, which is a load device, through the output terminal 2a on the secondary side, and lights the light 3. At this time, the open circuit detection device 4 generates a normal value voltage 30 and a waveform between the output terminals 2a on the secondary side of the current transformer, as shown at point 20 in the operating characteristic diagram of the open circuit detection device in FIG. , a secondary circuit current 31 flows through the lamp 3. The magnitude of the voltage 30 in such a normal state is lower than the discharge starting voltage determined for the arrester 5 in the open detection device 4, so the arrester 5 does not discharge, and the light emitting part of the photocoupler 8 and the diode 7
Since no current flows through the opening detection device 4 does not operate. Therefore, the control device 11 does not operate the protective contact 10 and output the open signal 9, and the protective contact 10 remains open.
【００１１】次いで灯火３が断芯すると灯火３が消え、
この断芯により変流器２の２次回路は開放されるので、
図２の点２１におけるように電流３１は消滅するが、電
圧３０は急峻な波形の高電圧３０ａが変流器２の出力端
子２ａ間に出現する。この高電圧３０ａはこのままの状
態で放置しておくと、２次回路全体即ち２次回路を形成
している変流器２を含む配線部分等全てが、過電圧によ
る絶縁破壊に至る危険にさらされる。[0011] Next, when the light 3 is broken, the light 3 goes out.
This disconnection opens the secondary circuit of current transformer 2, so
As at point 21 in FIG. 2, the current 31 disappears, but a high voltage 30a with a steep waveform appears across the output terminal 2a of the current transformer 2. If this high voltage 30a is left as it is, the entire secondary circuit, that is, all the wiring parts including the current transformer 2 forming the secondary circuit, will be exposed to the risk of dielectric breakdown due to overvoltage. .
【００１２】しかしながらこの高電圧３０ａが開放検出
装置４に加わると、この電圧値がアレスタ５の放電開始
電圧を超えた時点でアレスタ５は直ちに放電して導通す
る。この時流れる放電電流は抵抗器６により制限される
と共に、ダイオード７とフォトカプラ８の発光部に対し
て交互に半波づつ流れる。この放電電流により発光部は
発光し、この光信号は電気的に絶縁された受光部で再び
電気信号に変換されてフォトカプラ８より断芯信号３２
として制御装置１１に出力される。However, when this high voltage 30a is applied to the open circuit detection device 4, the arrester 5 immediately discharges and becomes conductive when this voltage value exceeds the discharge start voltage of the arrester 5. The discharge current flowing at this time is limited by the resistor 6, and flows alternately in half waves to the light emitting portion of the diode 7 and photocoupler 8. This discharge current causes the light emitting section to emit light, and this optical signal is converted into an electric signal again by the electrically insulated light receiving section, and the photocoupler 8 sends a disconnection signal 32.
It is output to the control device 11 as .
【００１３】なおこの出力は開放検出装置４からの開放
検出信号でもある。この出力は制御装置１１において変
流器２の２次回路開放信号と誤りがちな外部要因の一つ
である例えば雷ノイズ等によるものでないことの確認を
するために、この断芯信号３２が所定数連続した信号で
あるか、あるいは同一ピッチで同一電圧であるか等のカ
ウント、あるいはチェックを行い、その結果、明らかに
２次回路が開放されたものと確認されると、図２の点２
２におけるように図示しない表示装置等への開放信号９
の出力と保護接点１０の閉作動が行われる。Note that this output is also an open detection signal from the open detection device 4. In order to confirm in the control device 11 that this output is not caused by an external factor such as lightning noise, which tends to be mistaken for the secondary circuit open signal of the current transformer 2, this disconnection signal 32 is set as a predetermined signal. After counting or checking whether there are several consecutive signals or whether the signals are the same pitch and the same voltage, if it is confirmed that the secondary circuit is clearly open, point 2 in Figure 2 is performed.
2, an open signal 9 to a display device, etc., not shown.
output and the protective contact 10 is closed.
【００１４】保護接点１０が閉じることにより変流器２
次側の出力端子２ａ間が短絡されるので、変流器２の２
次回路の開放はなくなり、電流３１が復活し、電圧３０
も低下して、その電圧値と波形は正常に復する。また電
圧３０が正常に復すと、アレスタ５における放電は直ち
に停止し、開放検出装置４からの断芯信号３２も消滅す
るが、予め制御装置１１内において信号保持回路と解除
回路を設けておけば、２次回路の開放確認が容易で、そ
の開放検出後の保全処置等が迅速に行える。When the protective contact 10 closes, the current transformer 2
Since the output terminals 2a on the next side are short-circuited, 2 of the current transformer 2
Next, the circuit is no longer open, the current 31 is restored, and the voltage 30
The voltage value and waveform return to normal. Furthermore, when the voltage 30 returns to normal, the discharge in the arrester 5 immediately stops, and the disconnection signal 32 from the open detection device 4 also disappears. However, a signal holding circuit and a release circuit must be provided in the control device 11 in advance. For example, it is easy to confirm that the secondary circuit is open, and maintenance measures can be quickly taken after the open circuit is detected.
【００１５】以上の結果、変流器２の２次回路の過電圧
による絶縁破壊等の発生は、速やかに、かつ自動的に検
知され、回避されると共に開放信号９により灯火点灯装
置の特定と、灯火３の断芯を検出することができるので
、当該灯火３（ランプ）の交換作業等が速やかに実施で
きる。また開放検出装置４は変流器２の２次回路におけ
る所定値以上の高電圧により作動させているので、その
結果は変流器２の１次電流の有無や変動による影響は受
けず、また、制御装置１１での判別により外部からの突
発的なノイズの侵入あるいは周囲温度よる影響等も受け
ない。As a result of the above, the occurrence of dielectric breakdown or the like due to overvoltage in the secondary circuit of the current transformer 2 can be quickly and automatically detected and avoided, and the light lighting device can be identified by the open signal 9. Since breakage of the light 3 can be detected, work such as replacement of the light 3 (lamp) can be carried out promptly. In addition, since the open detection device 4 is activated by a high voltage higher than a predetermined value in the secondary circuit of the current transformer 2, the result is not affected by the presence or absence of the primary current of the current transformer 2 or fluctuations. As a result of the determination made by the control device 11, there is no sudden intrusion of noise from the outside or the influence of ambient temperature.
【００１６】図３は本発明の他の実施例を示すブロック
構成図で、開放検出装置１２以外の構成は上記一実施例
と同様であり、その作用も大略変わりがないが開放検出
装置１２の構成において、アレスタ５と直列でフォトカ
プラ８の発光部と並列に接続する保護用で、かつ放電電
流の検出部をダイオードブリッジ１３としたので、フォ
トカプラ８の発光部に伝達される放電電流の検出信号が
全波信号となるため、上記一実施例の半波信号に比べて
単位時間当たりのフォトカプラ８への入力信号数が倍と
なり、従って開放検出装置１２の出力である断芯信号３
２の発信数も２倍で、制御装置１１における外来ノイズ
等との判定確認速度が２倍となり、判定処理が高速で行
える効果がある。FIG. 3 is a block diagram showing another embodiment of the present invention. The structure other than the open detection device 12 is the same as that of the above embodiment, and its operation is also roughly the same. In the configuration, the diode bridge 13 is used for protection and is connected in series with the arrester 5 and in parallel with the light emitting part of the photocoupler 8, and as a detection part of the discharge current. Since the detection signal is a full-wave signal, the number of input signals to the photocoupler 8 per unit time is doubled compared to the half-wave signal of the above embodiment, and therefore the disconnection signal 3 which is the output of the open detection device 12
The number of transmissions in 2 is also twice as high, and the speed at which the control device 11 confirms the judgment against external noise etc. is doubled, which has the effect of allowing the judgment process to be performed at high speed.
【００１７】また、上記一実施例及び他の実施例に示し
たフォトカプラ８を図示しないフォトモスリレーに代え
ることにより、その作用効果を変えずに駆動電源を交流
とすることができる他、装置の構成を簡素化することが
できる。Furthermore, by replacing the photocoupler 8 shown in the above embodiment and other embodiments with a photoMOS relay (not shown), the driving power source can be changed to AC without changing its function and effect, and the device can also be The configuration can be simplified.
【００１８】なお、上記実施例は、いずれも負荷装置を
灯火３（ランプ）で、変流器２の２次回路が開放される
原因を灯火の断芯とし、さらに本開放検出装置４，１２
による１基の変流器２の２次回路の開放検出をもとにし
て、この開放検出信号を負荷装置である灯火３の断芯信
号３２として灯火３の断芯検出、あるいは保護接点１０
の作動信号として変流器２の２次回路を短絡させて、変
流器２を含む２次回路の保護をするとして説明したが、
負荷装置は灯火３に限らず、また２次回路の開放原因も
灯火の断芯のみに限定されず、回路の断線等によっても
発生する。さらに制御装置１１における断芯信号３２と
外来ノイズの判別を３個の断芯信号３２を基準として図
示したがこの判断基準も必要に応じて適宜変更すること
は容易である。In each of the above embodiments, the load device is a light 3 (lamp), the cause of the opening of the secondary circuit of the current transformer 2 is a break in the light, and the main open detection devices 4, 12 are used.
Based on the detection of an open circuit in the secondary circuit of one current transformer 2 by
It has been explained that the secondary circuit of the current transformer 2 is short-circuited as an activation signal to protect the secondary circuit including the current transformer 2.
The load device is not limited to the light 3, and the cause of the opening of the secondary circuit is not limited to a break in the light, but may also occur due to a break in the circuit, etc. Further, although the discrimination between the core breakage signal 32 and external noise in the control device 11 is illustrated using three core breakage signals 32 as a reference, it is easy to change this determination criterion as appropriate.
【００１９】[0019]
【発明の効果】以上本発明によれば簡易な装置でありな
がら変流器の２次回路が開放した際に、１次電流や周囲
温度及びノイズ等、外部からの影響を受けずに、これを
精度良く迅速に検出するので、この検出信号を利用して
変流器を含む２次回路の保護のみならず、負荷装置の状
態も容易に監視することができる効果がある。[Effects of the Invention] Although the present invention is a simple device, when the secondary circuit of a current transformer is opened, the current transformer can be operated without being affected by external influences such as the primary current, ambient temperature, and noise. Since the detection signal is detected quickly and accurately, it is possible to use this detection signal not only to protect the secondary circuit including the current transformer, but also to easily monitor the condition of the load device.
【図１】本発明の灯火点灯装置に採用した場合を示すブ
ロック構成図。FIG. 1 is a block configuration diagram showing a case where the lamp lighting device of the present invention is adopted.
【図２】図１における作動特性図。FIG. 2 is an operational characteristic diagram in FIG. 1.
【図３】本発明の他の実施例でダイオードブリッジ採用
を示すブロック構成図。FIG. 3 is a block diagram showing the use of a diode bridge in another embodiment of the present invention.
２…変流器、２ａ…出力端子、３…灯火、４，１２…開
放検出装置、５…アレスタ、６…抵抗器、７…ダイオー
ド、８…フォトカプラ、９…開放信号、１０…保護接点
、１１…制御装置、１３…ダイオードブリッジ、３０…
電圧、３０ａ…高電圧、３１…電流、３２…断芯信号。2...Current transformer, 2a...Output terminal, 3...Light, 4, 12...Open detection device, 5...Arrester, 6...Resistor, 7...Diode, 8...Photocoupler, 9...Open signal, 10...Protective contact , 11...control device, 13...diode bridge, 30...
Voltage, 30a... High voltage, 31... Current, 32... Breaking signal.
Claims (1)
負荷装置よりなる変流器の２次回路において、前記変流
器の２次出力端に接続した、所定電圧値を超過した時に
放電するアレスタと前記アレスタの放電電流により発光
する発光部及びこの発光部の発光を検知して外部に信号
を出力する受光部からなるフォトカプラを直列に接続す
ると共に前記フォトカプラの発光部と並列に接続した発
光部保護用素子からなる開放検出装置を備えたことを特
徴とする変流器２次回路の開放検出装置。Claim 1: In a secondary circuit of a current transformer consisting of a current transformer and a load device connected to the secondary output terminal, the voltage connected to the secondary output terminal of the current transformer exceeds a predetermined voltage value. A photocoupler consisting of an arrester that discharges at the same time, a light emitting part that emits light by the discharge current of the arrester, and a light receiving part that detects the light emission from the light emitting part and outputs a signal to the outside is connected in series, and the light emitting part of the photocoupler and the light emitting part of the photocoupler are connected in series. 1. An open circuit detection device for a current transformer secondary circuit, comprising an open circuit detection device consisting of light emitting unit protection elements connected in parallel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12598491A JPH04351422A (en) | 1991-05-29 | 1991-05-29 | Open circuit detector for secondary circuit of current transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12598491A JPH04351422A (en) | 1991-05-29 | 1991-05-29 | Open circuit detector for secondary circuit of current transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04351422A true JPH04351422A (en) | 1992-12-07 |
Family
ID=14923852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12598491A Pending JPH04351422A (en) | 1991-05-29 | 1991-05-29 | Open circuit detector for secondary circuit of current transformer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04351422A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120236614A1 (en) * | 2011-03-14 | 2012-09-20 | Tohoku Ricoh Co., Ltd. | High voltage inverter device |
| CN102709901A (en) * | 2012-06-14 | 2012-10-03 | 北京恒源利通电力技术有限公司 | Overvoltage protection method and device of current transformer |
| JP2012222866A (en) * | 2011-04-04 | 2012-11-12 | Densoku Techno Co Ltd | Current transformer protector |
| CN104078963A (en) * | 2014-06-11 | 2014-10-01 | 安徽三和电力技术有限公司 | Secondary open circuit protection device for current mutual inductor |
| CN106684820A (en) * | 2016-11-09 | 2017-05-17 | 国网天津市电力公司 | Open circuit automatic protection device for secondary circuit of high voltage current transformer |
| CN107785870A (en) * | 2017-11-11 | 2018-03-09 | 河南森源电气股份有限公司 | A kind of current transformer and its secondary side open-circuit protecting device |
| CN107785869A (en) * | 2017-11-08 | 2018-03-09 | 河南森源电气股份有限公司 | A kind of current transformer and its secondary side protective arrangement for limiting output voltage |
| CN108362922A (en) * | 2018-01-23 | 2018-08-03 | 宁波三星医疗电气股份有限公司 | CT secondary circuit power theft monitoring methods based on genetic algorithm frequency-selecting |
-
1991
- 1991-05-29 JP JP12598491A patent/JPH04351422A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120236614A1 (en) * | 2011-03-14 | 2012-09-20 | Tohoku Ricoh Co., Ltd. | High voltage inverter device |
| US9160225B2 (en) * | 2011-03-14 | 2015-10-13 | Ricoh Company, Ltd. | High voltage inverter device |
| JP2012222866A (en) * | 2011-04-04 | 2012-11-12 | Densoku Techno Co Ltd | Current transformer protector |
| CN102709901A (en) * | 2012-06-14 | 2012-10-03 | 北京恒源利通电力技术有限公司 | Overvoltage protection method and device of current transformer |
| CN104078963A (en) * | 2014-06-11 | 2014-10-01 | 安徽三和电力技术有限公司 | Secondary open circuit protection device for current mutual inductor |
| CN106684820A (en) * | 2016-11-09 | 2017-05-17 | 国网天津市电力公司 | Open circuit automatic protection device for secondary circuit of high voltage current transformer |
| CN107785869A (en) * | 2017-11-08 | 2018-03-09 | 河南森源电气股份有限公司 | A kind of current transformer and its secondary side protective arrangement for limiting output voltage |
| CN107785870A (en) * | 2017-11-11 | 2018-03-09 | 河南森源电气股份有限公司 | A kind of current transformer and its secondary side open-circuit protecting device |
| CN107785870B (en) * | 2017-11-11 | 2023-11-24 | 河南森源电气股份有限公司 | Current transformer and secondary side open circuit protection device thereof |
| CN108362922A (en) * | 2018-01-23 | 2018-08-03 | 宁波三星医疗电气股份有限公司 | CT secondary circuit power theft monitoring methods based on genetic algorithm frequency-selecting |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4618907A (en) | Desensitized ground fault interrupter | |
| US7400478B2 (en) | Arc detection circuit | |
| US4027204A (en) | Phase failure detection circuit for multi-phase systems | |
| US10557883B2 (en) | Leakage current detection and protection device for power cord | |
| US6359763B1 (en) | Monitoring apparatus for electrical circuits | |
| JPH04351422A (en) | Open circuit detector for secondary circuit of current transformer | |
| US20030143503A1 (en) | Industrial flame sensor communication system | |
| JPH0254025B2 (en) | ||
| JP6372926B2 (en) | Switch | |
| KR200200399Y1 (en) | Error detector of lamp control circuit | |
| JP2665567B2 (en) | Disconnection detection circuit | |
| JP2728561B2 (en) | Electronic device with printed board insulation deterioration detection means | |
| US3755799A (en) | Ultraviolet flame detector | |
| EP0051907B1 (en) | Testing arrangement for a control system | |
| KR100745835B1 (en) | Leakage current sensor type power off device | |
| EP0991042A2 (en) | Signalling device and monitoring system | |
| KR100683926B1 (en) | Leakage current sensor type power off device | |
| CN114362092B (en) | Load short-circuit protection circuit and electronic equipment | |
| GB2082752A (en) | Burner Igniter/Detector | |
| KR100321101B1 (en) | Fire detector | |
| KR200215803Y1 (en) | Fire-sensing apparatus having a test function | |
| JP2008159423A (en) | Switch state detector | |
| KR100193863B1 (en) | AC power detection circuit | |
| KR200179251Y1 (en) | The sensing device for grounding current | |
| RU5297U1 (en) | DEVICE FOR PROTECTING A RADIO ELECTRONIC INSTRUMENT AGAINST SHORT VOLTAGE VOLTAGE IN AC NETWORK |