JPH0720577U - Leakage current measuring device - Google Patents
Leakage current measuring deviceInfo
- Publication number
- JPH0720577U JPH0720577U JP5105993U JP5105993U JPH0720577U JP H0720577 U JPH0720577 U JP H0720577U JP 5105993 U JP5105993 U JP 5105993U JP 5105993 U JP5105993 U JP 5105993U JP H0720577 U JPH0720577 U JP H0720577U
- Authority
- JP
- Japan
- Prior art keywords
- current
- voltage
- detection sensor
- circuit
- current detection
- 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.)
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Abstract
(57)【要約】
【構成】 商用電源の相線Ｌ1に接続された第１のクラ
ンプ型電流検出センサ１と、クランプ型電流検出センサ
で検出された電流を第１の電圧に変換する第１の電流／
電圧変換回路２と、商用電源の接地相線Ｌ2に接続され
た第２のクランプ型電流検出センサ６と、第２のクラン
プ型電流検出センサで検出された電流を第２の電圧に変
換する第２の電流／電圧変換回路７と、第１の電流／電
圧変換回路で変換された第１の電圧から第２の電流／電
圧変換回路で変換された第２の電圧を減算する減算回路
１０と、減算回路から出力される減算電圧を整流する整
流回路１１と、整流回路の出力を対大地間漏洩電流とし
て表示するディスプレイ１２とを備えている。
【効果】 相線とは別に接地相線にもクランプ型電流検
出センサが使用することが可能となり、操作性が向上
し、簡単な回路構成で測定精度が極めて優れている。
(57) [Summary] [Structure] The first clamp type current detection sensor 1 connected to the phase line L 1 of the commercial power source and the first clamp type current detection sensor for converting the current detected by the clamp type current detection sensor into the first voltage. 1 current /
The voltage conversion circuit 2, the second clamp type current detection sensor 6 connected to the ground phase line L 2 of the commercial power supply, and the current detected by the second clamp type current detection sensor are converted into a second voltage. A second current / voltage conversion circuit 7 and a subtraction circuit 10 for subtracting the second voltage converted by the second current / voltage conversion circuit from the first voltage converted by the first current / voltage conversion circuit. A rectifying circuit 11 for rectifying the subtracted voltage output from the subtracting circuit, and a display 12 for displaying the output of the rectifying circuit as a leakage current to ground. [Effect] The clamp type current detection sensor can be used not only for the phase line but also for the ground phase line, the operability is improved, and the measurement accuracy is extremely excellent with a simple circuit configuration.
Description
【０００１】[0001]
本考案は、漏洩電流測定装置に関し、特に負荷が接続された状態で対大地間漏 洩電流が測定できる漏洩電流測定装置に係わる。 The present invention relates to a leakage current measuring device, and more particularly, to a leakage current measuring device capable of measuring a leakage current to ground with a load connected.
【０００２】[0002]
従来から、病院、オフィスビル等では医療機器、電子機器、コンピューター等 電源を断にして漏洩電流を測定することができない場合がある。 また、最近の集合住宅、病院、オフィスビルでは、配電盤に設けるノーヒュー ズブレーカを一極ブレーカとし、接地側を配電盤の下部に集合端子を設ける配線 構造とし、配電盤の小型、多回路化を図つている。 Conventionally, in hospitals, office buildings, etc., it may not be possible to measure leakage current by turning off the power of medical equipment, electronic equipment, computers, etc. In recent housing complexes, hospitals, and office buildings, the no-fuse breaker installed on the switchboard is used as a one-pole breaker, and the ground side has a wiring structure with a collective terminal at the bottom of the switchboard, aiming to make the switchboard small and have multiple circuits. .
【０００３】[0003]
このような配線構造では、商用電源の相線と接地相線を一括してクランプ型電 流検出センサでクランプできないので、漏洩電流の測定が出来ないという難点が ある。 In such a wiring structure, the phase line of the commercial power supply and the ground phase line cannot be clamped together by the clamp-type current detection sensor, so that the leakage current cannot be measured.
【０００４】[0004]
本考案は、上述した難点を解消するためになされたもので、相線とは別に接地 相線にもクランプ型電流検出センサが使用でき、操作性が向上し、簡単な回路構 成で測定精度が極めて良い漏洩電流測定装置を提供することを目的とする。 The present invention has been made in order to solve the above-mentioned difficulties, and a clamp type current detection sensor can be used not only for the phase wire but also for the ground phase wire, which improves the operability and improves the measurement accuracy with a simple circuit configuration. Aims to provide an extremely good leakage current measuring device.
【０００５】[0005]
この目的を達成するため、本考案による漏洩電流測定装置は、商用電源の相線 に接続された第１のクランプ型電流検出センサと、クランプ型電流検出センサで 検出された電流を第１の電圧に変換する第１の電流／電圧変換回路と、商用電源 の接地相線に接続された第２のクランプ型電流検出センサと、第２のクランプ型 電流検出センサで検出された電流を第２の電圧に変換する第２の電流／電圧変換 回路と、第１の電流／電圧変換回路で変換された第１の電圧から第２の電流／電 圧変換回路で変換された第２の電圧を減算する減算回路と、減算回路から出力さ れる減算電圧を整流する整流回路と、整流回路の出力を対大地間漏洩電流として 表示するディスプレイとを備えている。 In order to achieve this object, the leakage current measuring device according to the present invention uses a first clamp type current detection sensor connected to a phase line of a commercial power source and a current detected by the clamp type current detection sensor as a first voltage. To a second clamp-type current detection sensor connected to the ground phase line of the commercial power supply, and the current detected by the second clamp-type current detection sensor to the second A second current / voltage conversion circuit for converting to a voltage and a second voltage converted by the second current / voltage conversion circuit is subtracted from the first voltage converted by the first current / voltage conversion circuit And a rectifier circuit that rectifies the subtracted voltage output from the subtractor circuit, and a display that displays the output of the rectifier circuit as a leakage current to ground.
【０００６】[0006]
商用電源の相線に接続された第１のクランプ型電流検出センサで検出された電 流を第１の電流／電圧変換回路で第１の電圧に変換する。また、商用電源の接地 相線に接続された第２のクランプ型電流検出センサで検出された電流を第２の電 流／電圧変換回路で第２の電圧に変換する。 The current detected by the first clamp type current detection sensor connected to the phase line of the commercial power supply is converted into the first voltage by the first current / voltage conversion circuit. Further, the current detected by the second clamp type current detection sensor connected to the ground phase wire of the commercial power source is converted into the second voltage by the second current / voltage conversion circuit.
【０００７】 次に減算回路で第１の電流／電圧変換回路で変換された第１の電圧から第２の 電流／電圧変換回路で変換された第２の電圧を減算する。整流回路でこの減算さ れた電圧を整流し、ディスプレイで対大地間漏洩電流として表示する。Next, the subtraction circuit subtracts the second voltage converted by the second current / voltage conversion circuit from the first voltage converted by the first current / voltage conversion circuit. The rectified circuit rectifies this subtracted voltage and displays it as a leakage current to earth on the display.
【０００８】[0008]
以下、本考案による漏洩電流測定装置の好ましい一実施例を図面に従つて説明 する。 本考案による漏洩電流測定装置は図１に示すように、商用電源の相線Ｌ1に接 続された第１のクランプ型電流検出センサ１と、クランプ型電流検出センサで検 出された電流を第１の電圧に変換する第１の電流／電圧変換回路２と、商用電源 の接地相線Ｌ2に接続された第２のクランプ型電流検出センサ６と、第２のクラ ンプ型電流検出センサで検出された電流を第２の電圧に変換する第２の電流／電 圧変換回路７と、第１の電流／電圧変換回路で変換された第１の電圧から第２の 電流／電圧変換回路で変換された第２の電圧を減算する減算回路１０と、減算回 路から出力される減算電圧を整流する整流回路１１と、整流回路の出力を対大地 間漏洩電流として表示するディスプレイ１２とを備えている。Hereinafter, a preferred embodiment of the leakage current measuring device according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the leakage current measuring device according to the present invention provides a first clamp type current detecting sensor 1 connected to a phase line L 1 of a commercial power source and a current detected by the clamp type current detecting sensor. A first current / voltage conversion circuit 2 for converting to a first voltage, a second clamp type current detection sensor 6 connected to a ground phase line L 2 of a commercial power supply, and a second clamp type current detection sensor. Second current / voltage conversion circuit 7 for converting the current detected in step 2 into a second voltage, and a second current / voltage conversion circuit converted from the first voltage converted by the first current / voltage conversion circuit A subtraction circuit 10 for subtracting the second voltage converted by the above, a rectification circuit 11 for rectifying the subtraction voltage output from the subtraction circuit, and a display 12 for displaying the output of the rectification circuit as a leakage current to ground. I have it.
【０００９】 相線Ｌ1をクランプ部材１ａでクランプする２０００ターンのコアー１ｂを設 けた相線用クランプ型電流検出センサ１は電流検出端子Ｔ1とＴ2とシールド線Ｌ 3を介して相線用電流／電圧変換回路２と接続されている。 接地相線Ｌ2をクランプ部材６ａでクランプする２０００ターンのコアー６ｂ を設けた接地相線用クランプ型電流検出センサ６は電流検出端子Ｔ3、Ｔ4及びシ ールド線Ｌ4を介して接地相線用電流／電圧変換回路７と接続されている。なを 、接地相線Ｌ2は外部の柱上変圧器等で２種アースＧ2に接続され、内部の接地相 線Ｌ2と相線Ｌ1には医療機器、電子機器、コンピューター等の負荷３０が接続さ れている。A clamp-type current detection sensor 1 for phase wire provided with a 2000-turn core 1b for clamping the phase wire L 1 with a clamp member 1a includes a phase wire via current detection terminals T 1 and T 2 and a shield wire L 3. It is connected to the current / voltage conversion circuit 2 for use. Ground phase line L 2 ground phase wire clamp type current sensor 6 having a 2000 turn of the core 6b for clamping by the clamping members 6a and via the current detection terminals T 3, T 4 and cysteinyl Rudo line L 4 ground phase It is connected to the line current / voltage conversion circuit 7. The ground phase line L 2 is connected to the second ground G 2 by an external pole transformer, etc., and the internal ground phase line L 2 and phase line L 1 are connected to the load of medical equipment, electronic equipment, computers, etc. 30 is connected.
【００１０】 更に、相線用電流／電圧変換回路２と接地相線用電流／電圧変換回路７のそれ ぞれの出力側は減算値を２０倍する減算回路１０を経由して整流回路１１の入力 側と接続され、出力側はディスプレイ１２と接続されている。 電池１３は電源スイッチＳＷを接にすると各部回路に電源＋Ｂを供給する。 上記構成の漏洩電流測定装置において、相線Ｌ1に２０Ａの電流と１０ｍＡの 漏洩電流が流れているとすれば、相線用クランプ型電流検出センサ１の検出電流 は２０.０１÷２０００＝１０.００５ｍＡとなる。また、接地相線用クランプ型 電流検出センサ６では２０÷２０００＝１０ｍＡとなる。Further, the output side of each of the phase line current / voltage conversion circuit 2 and the ground phase line current / voltage conversion circuit 7 is connected to the rectification circuit 11 via a subtraction circuit 10 that multiplies the subtraction value by 20. It is connected to the input side and the output side is connected to the display 12. When the power switch SW is turned on, the battery 13 supplies power + B to each circuit. In the leakage current measuring device having the above configuration, if a current of 20 A and a leakage current of 10 mA are flowing in the phase line L 1 , the detected current of the phase line clamp type current detection sensor 1 is 20.01 ÷ 2000 = 10. It will be 0.005 mA. Further, in the clamp type current detection sensor 6 for the ground phase wire, 20 ÷ 2000 = 10 mA.
【００１１】 相線用電流／電圧変換回路２と接地相線用電流／電圧変換回路７で１０.００ ５ｍＡと１０ｍＡを電圧に変換すると、それぞれの出力は１.０００５Ｖと１Ｖ となり、減算回路１０で１.０００５Ｖから１Ｖを減算し、２０倍すると１０ｍ Ｖとなる。 この、１０ｍＶを整流回路１１で整流するとフルスケール１９９.９ｍＶのデ ィスプレイ１２に漏洩電流１０ｍＶを表示する。When the phase line current / voltage conversion circuit 2 and the ground phase line current / voltage conversion circuit 7 convert 10.05 mA and 10 mA to voltage, the respective outputs become 1.0005 V and 1 V, and the subtraction circuit 10 Then, subtract 1V from 1.0005V and multiply by 20 to get 10mV. When this 10 mV is rectified by the rectifying circuit 11, a leak current of 10 mV is displayed on the full scale 199.9 mV display 12.
【００１２】 図２に電池内蔵のディスプレイ１２を実装した筐体１４を有する漏洩電流測定 装置示す。筐体１４にはシールド線Ｌ3、Ｌ4を介して、相線用クランプ型電流検 出センサ１と接地相線用クランプ型電流検出センサ６が接続されている。 図３に筐体１４を設けない漏洩電流測定装置を示す。この、漏洩電流測定装置 では相線用クランプ型電流検出センサ１と接地相線用クランプ型電流検出センサ ６をシールド線Ｌ5せ接続し、接地相線用クランプ型電流検出センサ６に電池を 内蔵しディスプレイ１２を実装している。FIG. 2 shows a leakage current measuring apparatus having a housing 14 in which a display 12 with a built-in battery is mounted. The phase wire clamp type current detection sensor 1 and the ground phase wire clamp type current detection sensor 6 are connected to the housing 14 via shielded lines L 3 and L 4 . FIG. 3 shows a leakage current measuring device without the housing 14. In this leakage current measuring device, the clamp-type current detection sensor 1 for phase wire and the clamp-type current detection sensor 6 for ground phase wire are connected to the shield wire L 5, and the clamp-type current detection sensor 6 for ground phase wire has a built-in battery. The display 12 is mounted.
【００１３】 図４に１極のノーヒューズブレーカ２１ａ〜２１ｅの配電盤２０に漏洩電流測 定装置を接続いた様子を示す。 配電盤２０にはノーヒューズブレーカ２１ａ〜２１ｅが設けられ、このノーヒ ューズブレーカ２１ａ〜２１ｅの下部には接地相線２３ａ〜２３ｅを設けた接地 相線用集合端子盤が配置されている。接地相線２３ａの配線を接地相線用クラン プ型電流検出センサ６のクランプ部材６ａでクランプし、ノーヒューズブレーカ ２１ａの配線を相線用クランプ型電流検出センサ１のクランプ部材１ａでクラン プする。FIG. 4 shows a state in which a leakage current measuring device is connected to the switchboard 20 of the one-pole no-fuse breakers 21a to 21e. No-fuse breakers 21a to 21e are provided on the switchboard 20, and a ground phase wire collective terminal board provided with ground phase wires 23a to 23e is arranged below the no fuse breakers 21a to 21e. The wiring of the ground phase wire 23a is clamped by the clamp member 6a of the clamp type current detection sensor 6 for ground phase wire, and the wiring of the no-fuse breaker 21a is clamped by the clamp member 1a of the clamp type current detection sensor 1 for phase wire. .
【００１４】[0014]
以上のように実施例からも明らかなように本考案の漏洩電流測定装置によれば 、商用電源の相線に接続された第１のクランプ型電流検出センサと、クランプ型 電流検出センサで検出された電流を第１の電圧に変換する第１の電流／電圧変換 回路と、商用電源の接地相線に接続された第２のクランプ型電流検出センサと、 第２のクランプ型電流検出センサで検出された電流を第２の電圧に変換する第２ の電流／電圧変換回路と、第１の電流／電圧変換回路で変換された第１の電圧か ら第２の電流／電圧変換回路で変換された第２の電圧を減算する減算回路と、減 算回路から出力される減算電圧を整流する整流回路と、整流回路の出力を対大地 間漏洩電流として表示するディスプレイとを備えているので、相線とは別に接地 相線にもクランプ型電流検出センサを使用することが可能となり、操作性が向上 し、簡単な回路構成で測定精度が極めて優れている。 As described above, according to the leakage current measuring device of the present invention, as is apparent from the embodiments, it is detected by the first clamp type current detection sensor connected to the phase line of the commercial power source and the clamp type current detection sensor. Detected by the first current / voltage conversion circuit that converts the generated current into the first voltage, the second clamp type current detection sensor connected to the ground phase line of the commercial power supply, and the second clamp type current detection sensor. A second current / voltage conversion circuit that converts the generated current to a second voltage, and the first voltage converted by the first current / voltage conversion circuit from the first voltage that is converted by the second current / voltage conversion circuit. Since it has a subtracting circuit for subtracting the second voltage, a rectifying circuit for rectifying the subtracted voltage output from the subtracting circuit, and a display for displaying the output of the rectifying circuit as a ground leakage current, Separated from the ground wire It becomes possible to use type current detection sensor, and improving the operability, the measurement accuracy by a simple circuit structure is excellent.
【図１】本考案における漏洩電流測定装置の一実施例を
示すブロック図。FIG. 1 is a block diagram showing an embodiment of a leakage current measuring device according to the present invention.
【図２】本考案における漏洩電流測定装置の構成図。FIG. 2 is a block diagram of a leakage current measuring device according to the present invention.
【図３】本考案における漏洩電流測定装置の構成図。FIG. 3 is a block diagram of a leakage current measuring device according to the present invention.
【図４】本考案における漏洩電流測定装置を配電盤に装
着した場合の構成図。FIG. 4 is a configuration diagram of the leakage current measuring device according to the present invention mounted on a switchboard.
１・・・・・・相線用クランプ型電流検出センサ（第１のクラ
ンプ型電流検出センサ） ２・・・・・・相線用電流／電圧変換回路（第１の電流／電圧
変換回路） ６・・・・・・接地相線用クランプ型電流検出センサ（第２の
クランプ型電流検出センサ） ７・・・・・・接地相線用電流／電圧変換回路（第２の電流／
電圧変換回路） １０・・・・・・減算回路 １１・・・・・・整流回路 １２・・・・・・ディスプレイ1 --- Clamp type current detection sensor for phase wire (first clamp-type current detection sensor) 2 ...- Current / voltage conversion circuit for phase wire (first current / voltage conversion circuit) 6- ・ Clamp-type current detection sensor for ground phase wire (second clamp-type current detection sensor) 7- ・ Current / voltage conversion circuit for ground phase wire (second current /
Voltage conversion circuit) 10 --- Subtraction circuit 11 --- Rectification circuit 12 --- Display
フロントページの続き (72)考案者 清家敬司 愛媛県東宇和郡宇和町大字坂戸480 共立 電気計器株式会社内Continuation of the front page (72) Keiji Seike 480 Sakado, Uwa-cho, Higashi-Uwa-gun, Ehime Prefecture Kyoritsu Electric Instrument Co., Ltd.
Claims (1)
プ型電流検出センサと、前記クランプ型電流検出センサ
で検出された電流を第１の電圧に変換する第１の電流／
電圧変換回路と、前記商用電源の接地相線に接続された
第２のクランプ型電流検出センサと、前記第２のクラン
プ型電流検出センサで検出された電流を第２の電圧に変
換する第２の電流／電圧変換回路と、前記第１の電流／
電圧変換回路で変換された第１の電圧から前記第２の電
流／電圧変換回路で変換された第２の電圧を減算する減
算回路と、前記減算回路から出力される減算電圧を整流
する整流回路と、前記整流回路の出力を対大地間漏洩電
流として表示するディスプレイとを備えたことを特徴と
する漏洩電流測定装置。1. A first clamp type current detection sensor connected to a phase line of a commercial power source, and a first current / current for converting a current detected by the clamp type current detection sensor into a first voltage /
A voltage conversion circuit, a second clamp type current detection sensor connected to the ground phase line of the commercial power supply, and a second for converting the current detected by the second clamp type current detection sensor into a second voltage. Current / voltage conversion circuit, and the first current /
A subtraction circuit for subtracting the second voltage converted by the second current / voltage conversion circuit from the first voltage converted by the voltage conversion circuit, and a rectification circuit for rectifying the subtracted voltage output from the subtraction circuit And a display for displaying the output of the rectifier circuit as a leakage current to ground leakage current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5105993U JPH0720577U (en) | 1993-09-20 | 1993-09-20 | Leakage current measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5105993U JPH0720577U (en) | 1993-09-20 | 1993-09-20 | Leakage current measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0720577U true JPH0720577U (en) | 1995-04-11 |
Family
ID=12876238
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5105993U Withdrawn JPH0720577U (en) | 1993-09-20 | 1993-09-20 | Leakage current measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0720577U (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109633254A (en) * | 2019-01-15 | 2019-04-16 | 广东电网有限责任公司 | A kind of clamp on amperemeter for a flow-through test |
| WO2019215836A1 (en) * | 2018-05-09 | 2019-11-14 | 理化工業株式会社 | Current-measurement and current-leakage-detection device and power control device |
| JP2020026967A (en) * | 2018-08-09 | 2020-02-20 | 株式会社日立製作所 | Diagnostic device and diagnostic method of electric machine and rotary electric machine |
| US20210084718A1 (en) * | 2019-09-16 | 2021-03-18 | Rosemount Aerospace Inc. | Monitoring and extending heater life through power supply polarity switching |
| US11630140B2 (en) | 2020-04-22 | 2023-04-18 | Rosemount Aerospace Inc. | Prognostic health monitoring for heater |
| US11639954B2 (en) | 2019-05-29 | 2023-05-02 | Rosemount Aerospace Inc. | Differential leakage current measurement for heater health monitoring |
-
1993
- 1993-09-20 JP JP5105993U patent/JPH0720577U/en not_active Withdrawn
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019215836A1 (en) * | 2018-05-09 | 2019-11-14 | 理化工業株式会社 | Current-measurement and current-leakage-detection device and power control device |
| JPWO2019215836A1 (en) * | 2018-05-09 | 2021-01-07 | 理化工業株式会社 | Current measurement and leakage detection device, power control device |
| JP2020026967A (en) * | 2018-08-09 | 2020-02-20 | 株式会社日立製作所 | Diagnostic device and diagnostic method of electric machine and rotary electric machine |
| CN109633254A (en) * | 2019-01-15 | 2019-04-16 | 广东电网有限责任公司 | A kind of clamp on amperemeter for a flow-through test |
| CN109633254B (en) * | 2019-01-15 | 2024-01-23 | 广东电网有限责任公司 | Clamp ammeter for primary through-flow test |
| US11639954B2 (en) | 2019-05-29 | 2023-05-02 | Rosemount Aerospace Inc. | Differential leakage current measurement for heater health monitoring |
| US20210084718A1 (en) * | 2019-09-16 | 2021-03-18 | Rosemount Aerospace Inc. | Monitoring and extending heater life through power supply polarity switching |
| US11930563B2 (en) * | 2019-09-16 | 2024-03-12 | Rosemount Aerospace Inc. | Monitoring and extending heater life through power supply polarity switching |
| US11630140B2 (en) | 2020-04-22 | 2023-04-18 | Rosemount Aerospace Inc. | Prognostic health monitoring for heater |
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| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19980305 |