JPH04131770A - Dielectric resistance measuring device for capacitor - Google Patents
Dielectric resistance measuring device for capacitorInfo
- Publication number
- JPH04131770A JPH04131770A JP25467490A JP25467490A JPH04131770A JP H04131770 A JPH04131770 A JP H04131770A JP 25467490 A JP25467490 A JP 25467490A JP 25467490 A JP25467490 A JP 25467490A JP H04131770 A JPH04131770 A JP H04131770A
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- fet
- constant current
- capacitor
- source
- 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.)
- Granted
Links
- 239000003990 capacitor Substances 0.000 title claims abstract description 32
- 238000005259 measurement Methods 0.000 claims description 27
- 238000009413 insulation Methods 0.000 claims description 14
- 230000000694 effects Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- SXAAVRUIADQETA-UHFFFAOYSA-N 2-chloro-n-(2-methoxyethyl)-n-(2-methylphenyl)acetamide Chemical compound COCCN(C(=O)CCl)C1=CC=CC=C1C SXAAVRUIADQETA-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はコンデンサの!!縁低抵抗測定するための絶縁
抵抗測定装置、特にコンデンサに流れる電流を一定化す
るための定電流回路に関するものである。[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to capacitors! ! This invention relates to an insulation resistance measuring device for measuring low edge resistance, and in particular to a constant current circuit for making the current flowing through a capacitor constant.
〔従来の技術]
一般に、コンデンサの絶縁抵抗測定では、耐圧測定も兼
ねるので、コンデンサの種類によって印加測定電圧も異
なる。また、印加時の初期電流は印加電圧が変わっても
一定であることが要求される。さらに、コンデンサは正
電圧を印加した場合と負電圧を印加した場合とで漏れ電
流が異なることがあるので、正逆の両電圧で測定する場
合もある。[Prior Art] Generally, when measuring the insulation resistance of a capacitor, it also measures the withstand voltage, so the applied measurement voltage varies depending on the type of capacitor. Further, the initial current during application is required to be constant even if the applied voltage changes. Furthermore, since the leakage current of a capacitor may differ depending on whether a positive voltage is applied or a negative voltage is applied, measurements may be performed using both positive and reverse voltages.
このような要求に応しるため、第2図のような絶縁抵抗
測定装置が提案されている。即ち、1は正弦波発生器、
2は正側の直流測定電源、3は負側の直/It測定電源
であり、それぞれの一端はアースされ、他端は切換器4
によって択一的に切り換えられる。なお、4aはアース
側端子である。切換器4は複数の制限抵抗5aを並列接
続してなるt流制限回路50入力端Aに接続され、この
電流制限回路5は切換器6によって任意の制限抵抗5a
を択一的に選択する。電流制限回路5の出力端Bは被検
体であるコンデンサ7の一端に接続され、コンデンサ7
の他端はOPアンプ8の負入力に接続される。なお、O
Pアンプ8の正入力はアースされている。OPアンプ8
の出力端は帰還抵抗9を介して負入力に接続されるとと
もに、切換器10とRMS/DC変換器11とに接続さ
れている。切換器10をOPアンプ側端子10aへ切り
換えると、OPアンプ8の出力はそのままA/D変換器
12へ送られ、切換器10をRMS/DC変換器側端子
10bへ切り換えると、OPアンプ8の出力はRMS/
DC変換器11を経てA/D変換器12へ送られる。な
お、この測定袋!では、回路を簡素化するため0Pアン
プ8の入力保護回路等は省略しである。In order to meet such demands, an insulation resistance measuring device as shown in FIG. 2 has been proposed. That is, 1 is a sine wave generator,
2 is a positive side DC measurement power supply, 3 is a negative side DC/It measurement power supply, one end of each is grounded, and the other end is connected to a switch 4.
can be selectively switched by. Note that 4a is a ground terminal. The switch 4 is connected to the input terminal A of a current limiting circuit 50 formed by connecting a plurality of limiting resistors 5a in parallel, and the current limiting circuit 5 is connected to an arbitrary limiting resistor 5a by a switch 6.
Select alternatively. The output end B of the current limiting circuit 5 is connected to one end of the capacitor 7 which is the test object.
The other end is connected to the negative input of the OP amplifier 8. In addition, O
The positive input of P amplifier 8 is grounded. OP amplifier 8
The output terminal of is connected to a negative input via a feedback resistor 9, and is also connected to a switch 10 and an RMS/DC converter 11. When the switch 10 is switched to the OP amplifier side terminal 10a, the output of the OP amplifier 8 is sent as is to the A/D converter 12, and when the switch 10 is switched to the RMS/DC converter side terminal 10b, the output of the OP amplifier 8 is sent to the A/D converter 12. Output is RMS/
The signal is sent to the A/D converter 12 via the DC converter 11. By the way, this measuring bag! Here, the input protection circuit of the 0P amplifier 8 and the like are omitted to simplify the circuit.
上記測定回路を用いて被検体であるコンデンサ7の!!
縁低抵抗測定する方法を説明する。Using the above measurement circuit, test capacitor 7! !
We will explain how to measure edge low resistance.
まず、コンデンサ7の種類により正負の測定電i2.a
の出力電圧を設定し、かつ規定のNmとなるように制限
抵抗5aの中から適切なものに切換器6を切り換える。First, depending on the type of capacitor 7, positive and negative measurement voltages i2. a
The output voltage is set, and the switch 6 is switched to an appropriate one from among the limiting resistors 5a so that the output voltage becomes the specified Nm.
次に、絶縁抵抗の測定に先立ち、コンデンサ7が正しく
測定端子に接触しているかを確認するため、切換器4を
正弦波発生器1側へ切り換え、回路に正弦波信号を流す
、同時に、切換器10をRMS/DC変換器側端子ta
bへ切り換える。°その結果、正弦波信号つまり交流信
号がコンデンサ7を通り、OPアンプ8で増幅された後
、RMS/DC変換器11で実効値に対応した直流信号
に変換される。そして、この直流信号をA/D変換器1
2でデジタル化し、解析する。デジタル化された信号が
基準以下であれば、接触不良である。Next, before measuring the insulation resistance, in order to check whether the capacitor 7 is correctly in contact with the measurement terminal, switch the switch 4 to the sine wave generator 1 side, apply a sine wave signal to the circuit, and at the same time switch Connector 10 to RMS/DC converter side terminal ta
Switch to b. As a result, a sine wave signal, that is, an AC signal passes through the capacitor 7, is amplified by the OP amplifier 8, and is then converted by the RMS/DC converter 11 into a DC signal corresponding to an effective value. Then, this DC signal is transferred to the A/D converter 1.
2. Digitize and analyze. If the digitized signal is below the standard, there is a poor contact.
接触が良好であれば、まずコンデンサ7の正電圧による
絶縁抵抗を測定する。この時、切換器4を正側の直流電
流2へ切り換えると同時に、切換器IOをOPアンプ側
端子10aへ切り換える。これにより、制限抵抗5aで
制限された電流はコンデンサ7に充電される。充電後、
コンデンサ7の漏れ電流をOPアンプ8でI/V変換し
、この出力電圧をA/D変換器12でデジタル化したも
のを解析し、電圧換算でコンデンサ7の絶縁抵抗を計算
する。If the contact is good, first measure the insulation resistance of the capacitor 7 due to positive voltage. At this time, the switch 4 is switched to the positive DC current 2, and at the same time, the switch IO is switched to the OP amplifier side terminal 10a. Thereby, the current limited by the limiting resistor 5a charges the capacitor 7. After charging,
The leakage current of the capacitor 7 is converted to I/V by the OP amplifier 8, and this output voltage is digitized by the A/D converter 12 and analyzed, and the insulation resistance of the capacitor 7 is calculated in terms of voltage.
逆電圧を測定する場合、コンデンサ7の正充電電圧を一
旦放電する必要があるため、切換器4をまずアース側端
子4aへ切り換え、ついで切換器4を負側の直2it電
流3へ切り換える。その後、上記の正電圧による絶縁抵
抗測定と同様にして、負電圧による絶縁抵抗測定が行わ
れる。When measuring the reverse voltage, it is necessary to once discharge the positive charging voltage of the capacitor 7, so first switch the switch 4 to the ground side terminal 4a, and then switch the switch 4 to the negative side direct 2IT current 3. Thereafter, insulation resistance measurement using a negative voltage is performed in the same manner as the insulation resistance measurement using a positive voltage described above.
〔発明が解決しようとする課題)
ところが、上記絶縁抵抗測定装置の場合、抵抗による電
流制限回路5を使用しているため、測定電′82.3の
電圧を変えると、充電電流が変化してしまうことになる
。そのため、測定する電圧値に応して制限抵抗5aを何
種類か用意して切り換える必要があり、回路が複翼化す
るとともに、切換に手間がかかるという問題があった。[Problem to be Solved by the Invention] However, in the case of the above-mentioned insulation resistance measuring device, since the current limiting circuit 5 using a resistor is used, changing the voltage of the measuring voltage '82.3 causes a change in the charging current. It will end up being put away. Therefore, it is necessary to prepare and switch between several types of limiting resistors 5a depending on the voltage value to be measured, resulting in a problem that the circuit becomes multi-blade and that switching takes time and effort.
また、コンデンサの充電がCRの時定数によるexpカ
ーブとなるため、充電時間がかかり、測定効率が悪いと
いう問題もあった。Furthermore, since the charging of the capacitor follows an exp curve based on the time constant of CR, there is a problem that charging time is required and measurement efficiency is poor.
そこで、本発明の目的は、測定電圧を代えてもコンデン
サに一定の電流を流すことができ、正逆の測定電圧の定
電流化が可能で、かつ測定効率の良好なコンデンサの絶
縁抵抗測定装置を提供することにある。SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a capacitor insulation resistance measuring device that allows a constant current to flow through a capacitor even when the measurement voltage is changed, that makes it possible to make the measurement voltage constant in both forward and reverse directions, and that has good measurement efficiency. Our goal is to provide the following.
上記目的を達成するために、本発明は、正と負の直流測
定電源と、何れかの測定NBに選択的に切り換える切換
器と、測定電源から切換器を介して供給される電流を一
定化する定電流回路と、定電流回路の出力端に接続され
る被検体であるコンデンサの漏れ電流を電圧に変換する
I/V変換器とを備え、I/V変換器の出力電圧により
コンデンサの絶縁抵抗を測定する測定装置において、上
記定電流回路は、正逆直列接続された2個のエンハンス
メント型FETと、各FETのソース−ドレイン間に並
列接続され、ソースからドレイン方向への電流の流れを
許容する保護ダイオードと、夫々のFETのゲート−ソ
ース間に直流電圧を印加する測定電源と独立したバイア
ス電源と、各FETのソースに直列接続された定電流負
帰還用の抵抗と、バイアス電源の出力電圧を分圧して各
FETのゲートに印加するゲート−ソース間電圧設定用
の抵抗とを備えてなるものである。In order to achieve the above object, the present invention provides positive and negative DC measurement power supplies, a switch that selectively switches to either measurement NB, and a constant current supplied from the measurement power supply via the switch. and an I/V converter that converts the leakage current of the capacitor under test connected to the output end of the constant current circuit into voltage. In a measuring device for measuring resistance, the constant current circuit has two enhancement type FETs connected in forward and reverse series, and is connected in parallel between the source and drain of each FET, and controls the flow of current from the source to the drain. A bias power supply independent of the measurement power supply that applies DC voltage between the gate and source of each FET, a resistor for constant current negative feedback connected in series to the source of each FET, and a bias power supply that applies a DC voltage between the gate and source of each FET. It also includes a resistor for setting a gate-source voltage that divides the output voltage and applies it to the gate of each FET.
測定taのtiJtは、定電流負帰還用の抵抗。 tiJt of measurement ta is a resistance for constant current negative feedback.
方のFET、他方のFET、定電流負帰還用の抵抗の順
に流れる。FETのドレイン−ソース間を流れる電流値
はゲート−ソー入間の電位差により決まる。ゲート−ソ
ース間の電位差は、バイアス電源の出力電圧をゲート−
ソース間電圧設定用の抵抗で分圧した電圧から、定電流
負帰還用の抵抗に電流が流れることによる電圧降下分を
差し引いたものとなるので、定電流負帰還用の抵抗を流
れる電流が増大すると、その電圧降下が大きくなり、ゲ
ート−ソース間の電位差が縮まり、そのためドレイン−
ソース間に流れる′:it流が小さくなる。このように
、FETの定電流特性を利用して測定電圧を変えても常
に一定の電流をコンデンサに流すことができる。また、
2個のFETは逆向きに接続されているので、片方のF
ETにはソースからドレイン方向へt211tが流れよ
うとし、二〇FETを損傷するおそれがあるので、保護
ダイオードが並列接続されている。したがって、この場
合には他方のFETによって定電流化を行う、このよう
に、正逆いずれの測定電圧が印加されても定電流化が可
能となる。The current flows through one FET, the other FET, and the constant current negative feedback resistor in this order. The value of the current flowing between the drain and source of the FET is determined by the potential difference between the gate and source. The potential difference between the gate and the source changes the output voltage of the bias power supply from the gate to the source.
The voltage drop due to current flowing through the constant current negative feedback resistor is subtracted from the voltage divided by the source-to-source voltage setting resistor, so the current flowing through the constant current negative feedback resistor increases. Then, the voltage drop increases, the potential difference between the gate and source decreases, and therefore the drain
The ':it flow flowing between the sources becomes smaller. In this way, by utilizing the constant current characteristics of the FET, a constant current can always be passed through the capacitor even if the measured voltage is changed. Also,
The two FETs are connected in opposite directions, so one FET
A protection diode is connected in parallel to prevent t211t from flowing from the source to the drain of the ET, potentially damaging the 20FET. Therefore, in this case, the current is made constant by the other FET. In this way, it is possible to make the current constant regardless of whether a forward or reverse measurement voltage is applied.
本発明においてエンハンスメント型FETを使用した理
由は、デプレション型FETでは高電圧に耐え得られず
、数百ボルトを印加するコンデンサの耐圧測定には不向
きであるのに対し、エンハンスメント型では高耐圧性を
備えているためである。The reason for using an enhancement type FET in the present invention is that a depletion type FET cannot withstand high voltage and is not suitable for measuring the withstand voltage of a capacitor that applies several hundred volts, whereas an enhancement type FET has a high withstand voltage. This is because it is equipped with
また、バイアス電源はエンハンスメント型FETのゲー
ト−ソース間に電位差を持たせるために用いられ、測定
電源やコンデンサとは独立したGNDレヘルを持つ電源
をいう。Further, the bias power supply is used to create a potential difference between the gate and source of the enhancement type FET, and is a power supply having a GND level independent of the measurement power supply and the capacitor.
(実施例] 第1図は本発明にかかる定電流回路の一例を示す。(Example] FIG. 1 shows an example of a constant current circuit according to the present invention.
入力端子Aは第2図における測定!#側に接続され、出
力端子Bはコンデンサ側に接続される。Input terminal A is measured in Figure 2! The output terminal B is connected to the # side, and the output terminal B is connected to the capacitor side.
20、21はA、B間に互いに逆向きに直列接続された
エンハンスメント型MO3−FETであり、FET20
21のソース(S) −ドレイン(D)間にはソー
スからドレイン方向への電流の流れを許容する内部保護
ダイオード22.23が並列接続されている。20 and 21 are enhancement type MO3-FETs connected in series between A and B in opposite directions, and FET20
Internal protection diodes 22 and 23 are connected in parallel between the source (S) and drain (D) of 21 to allow current to flow from the source to the drain.
A端とFET20のソース(S) との間、およびB
端とFET21のソース(S) との間には夫々定電流
負帰還用の可変抵抗24.25が接続され、FET20
21のゲー) (G)は夫々ゲート−ソース間電圧設定
用の可変抵抗26.27と接続されている。電圧設定用
の可変抵抗26.27の両端はバイアス電源の一例であ
るD C70C変換器28.29の二次側に接続されて
おり、各D C70C変換器28.29の二次側の負礒
が夫々A、B端と接続されている。なお、DC/DC変
換器28.29の一次側は共通の直2it電源30に接
続されている。Between the A terminal and the source (S) of FET20, and B
Variable resistors 24 and 25 for constant current negative feedback are connected between the ends and the source (S) of FET 21, respectively, and FET 20
21 (G) are respectively connected to variable resistors 26 and 27 for setting the gate-source voltage. Both ends of the variable resistor 26.27 for voltage setting are connected to the secondary side of the DC70C converter 28.29, which is an example of a bias power supply, and the negative resistance of the secondary side of each DC70C converter 28.29 is connected. are connected to terminals A and B, respectively. Note that the primary sides of the DC/DC converters 28 and 29 are connected to a common direct 2-it power supply 30.
上記構成の定電流回路において、被検体(コンデンサ7
)の正電圧による絶縁抵抗を測定する場合には、電流が
A端からB端へと流れる。この時、FET20側は内部
保護ダイオード22を流れ、定電流作用はFET21で
行う、即ち、FET21のゲート(G)にはD C70
C変換器29の出力電圧を可変抵抗27で分圧した電圧
が印加され、ソース(S)の電圧はB81tIに比べて
可変抵抗25に′@流が流れることによる電圧降下分だ
け高い、つまり、FET21のゲート(G)−ソース(
S)間の電位差は、DC/DC変換器29の出力電圧を
可変抵抗27で分圧した電圧から、可変抵抗25に電流
が流れることによる電圧降下分だけ差し引いたものとな
る。FET21のドレイン(D)−ソース(S)間を流
れる電流値はゲート(G)−ソース(S)間の電位差に
よって決定されるので、可変抵抗25を流れる電流が増
大すると、電圧−下が大きくなり、ゲート(G) −ソ
ース(S)間の電位差が縮まり、・これによりトルイン
(D)〜ソース(S)間を流れる電流が小さくなる。In the constant current circuit with the above configuration, the test object (capacitor 7
), current flows from the A end to the B end. At this time, the current flows through the internal protection diode 22 on the FET 20 side, and the constant current action is performed by the FET 21. That is, the gate (G) of the FET 21 has a DC70
A voltage obtained by dividing the output voltage of the C converter 29 by the variable resistor 27 is applied, and the source (S) voltage is higher than B81tI by the voltage drop caused by the current flowing through the variable resistor 25, that is, FET21 gate (G) - source (
The potential difference between S) is obtained by subtracting the voltage drop due to current flowing through the variable resistor 25 from the voltage obtained by dividing the output voltage of the DC/DC converter 29 by the variable resistor 27. The value of the current flowing between the drain (D) and the source (S) of the FET 21 is determined by the potential difference between the gate (G) and the source (S), so as the current flowing through the variable resistor 25 increases, the voltage decreases. As a result, the potential difference between the gate (G) and the source (S) is reduced, and the current flowing between the toluin (D) and the source (S) is thereby reduced.
このようにして、被検体に流れるt2itが自動的に一
定化される。In this way, t2it flowing through the subject is automatically made constant.
また、被検体の負電圧による絶縁抵抗を測定する場合に
は、電流がB端からA端へと流れるので、上記とは逆に
、FET21側は内部保護ダイオード23を流れ、定i
t流作用はFET20で行うことになる。Furthermore, when measuring the insulation resistance of the test object due to a negative voltage, the current flows from the B terminal to the A terminal, so on the FET 21 side it flows through the internal protection diode 23 and the constant i
The t current action will be performed by FET20.
なお、被検体が正しく測定端子に接触していることを確
認するため、本定電流回路に交流信号を流しても何ら支
障がない。Note that in order to confirm that the subject is correctly contacting the measurement terminal, there is no problem in flowing an alternating current signal through this constant current circuit.
上記実施例の定電流回路では、2個のFET2021を
ドレインコモンにして正逆直列接続したが、これを左右
入れ替えてソースコモンにして正逆直列接続しても同様
の効果を奏することは勿論である。また、バイアス電源
としてD C/D C変換器28、29を使用したのは
、F E T2O,21がエンハンスメント型であり、
かつ定電流回路の両端A、 Bがフローティングとな
っているからである。さらに、定電流負帰還用の抵抗2
4.25とゲート−ソース間電圧設定用の抵抗26.2
7として可変抵抗を使用したが、固定抵抗を使用して調
整を不要化してもよい。In the constant current circuit of the above embodiment, the two FETs 2021 are connected in forward and reverse series with the drain common, but it goes without saying that the same effect can be achieved even if the left and right are swapped and the sources are made common and connected in forward and reverse series. be. Furthermore, the reason why the DC/DC converters 28 and 29 were used as bias power supplies was that FET2O and 21 were of the enhancement type.
This is also because both ends A and B of the constant current circuit are floating. Furthermore, resistor 2 for constant current negative feedback
4.25 and resistor 26.2 for setting the gate-source voltage
Although a variable resistor is used as 7, a fixed resistor may be used to eliminate the need for adjustment.
以上の説明で明らかなように、本発明によれば、エンハ
ンスメント型FETの定電流特性を利用してコンデンサ
に流れる電流を一定化したので、従来の抵抗による電流
制限回路と異なり、印加測定電圧を変えても常に一定の
電流が得られ、多数の部品を必要とせず、かつ切換の手
間も必要としない。As is clear from the above explanation, according to the present invention, the current flowing through the capacitor is made constant by utilizing the constant current characteristics of the enhancement type FET. Even if the current is changed, a constant current is always obtained, and there is no need for many parts or effort for switching.
また、2個のFETを逆向きに直列接続しているので、
正逆いずれの電流に対しても定電流化でき、かつ交流電
流を流しても支障がない。Also, since two FETs are connected in series in opposite directions,
It can be made a constant current for both forward and reverse currents, and there is no problem even when an alternating current is passed.
さらに、従来の電流制限回路ではコンデンサの充電がC
Rの時定数によるexpカーブとなるので、充電時間が
かかるのに対し、本発明ではFETを使用しているので
、充電時間を格段に短縮でき、測定効率が良いという効
果がある。Furthermore, in conventional current limiting circuits, the charging of the capacitor is C
Since the exp curve is determined by the time constant of R, charging time is required, whereas in the present invention, since FET is used, the charging time can be significantly shortened and the measurement efficiency is high.
第1図は本発明にかかる定電流回路の一例の回路図、第
2図は従来の絶縁抵抗測定装置の回路図である。
2.3・・・測定電源、7・・・コンデンサ、8・・・
OPアンプ(1/V変換器) 、20.21・・・FE
T、2223・・・保護ダイオード、24.25・・・
定電流負帰還用抵抗、26.27・・・ゲート−ソース
間電圧設定用抵抗、28.29・・・バイアスta。
特許出願人 株式会社 村田製作所
代 理 人 弁理士 筒井 秀隆FIG. 1 is a circuit diagram of an example of a constant current circuit according to the present invention, and FIG. 2 is a circuit diagram of a conventional insulation resistance measuring device. 2.3...Measurement power supply, 7...Capacitor, 8...
OP amplifier (1/V converter), 20.21...FE
T, 2223...protection diode, 24.25...
Constant current negative feedback resistor, 26.27... Gate-source voltage setting resistor, 28.29... Bias ta. Patent applicant Murata Manufacturing Co., Ltd. Representative Patent attorney Hidetaka Tsutsui
Claims (1)
択的に切り換える切換器と、測定電源から切換器を介し
て供給される電流を一定化する定電流回路と、定電流回
路の出力端に接続される被検体であるコンデンサの漏れ
電流を電圧に変換するI/V変換器とを備え、I/V変
換器の出力電圧によりコンデンサの絶縁抵抗を測定する
測定装置において、 上記定電流回路は、正逆直列接続された2個のエンハン
スメント型FETと、各FETのソース−ドレイン間に
並列接続され、ソースからドレイン方向への電流の流れ
を許容する保護ダイオードと、夫々のFETのゲート−
ソース間に直流電圧を印加する測定電源と独立したバイ
アス電源と、各FETのソースに直列接続された定電流
負帰還用の抵抗と、バイアス電源の出力電圧を分圧して
各FETのゲートに印加するゲート−ソース間電圧設定
用の抵抗とを備えてなることを特徴とするコンデンサの
絶縁抵抗測定装置。(1) Positive and negative DC measurement power supplies, a switch that selectively switches to either measurement power supply, a constant current circuit that stabilizes the current supplied from the measurement power supply via the switch, and a constant current circuit A measuring device that measures the insulation resistance of the capacitor based on the output voltage of the I/V converter, which is equipped with an I/V converter that converts the leakage current of the capacitor being tested into voltage, which is connected to the output terminal of the I/V converter. The constant current circuit includes two enhancement type FETs connected in forward and reverse series, a protection diode connected in parallel between the source and drain of each FET to allow current to flow from the source to the drain, and each FET. gate of
A bias power supply independent of the measurement power supply that applies a DC voltage between the sources, a resistor for constant current negative feedback connected in series to the source of each FET, and the output voltage of the bias power supply divided and applied to the gate of each FET. 1. A capacitor insulation resistance measuring device, comprising: a resistor for setting a gate-source voltage.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP25467490A JP2949242B2 (en) | 1990-09-25 | 1990-09-25 | Capacitor insulation resistance measuring device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP25467490A JP2949242B2 (en) | 1990-09-25 | 1990-09-25 | Capacitor insulation resistance measuring device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH04131770A true JPH04131770A (en) | 1992-05-06 |
JP2949242B2 JP2949242B2 (en) | 1999-09-13 |
Family
ID=17268289
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP25467490A Expired - Lifetime JP2949242B2 (en) | 1990-09-25 | 1990-09-25 | Capacitor insulation resistance measuring device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2949242B2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6127828A (en) * | 1997-05-09 | 2000-10-03 | Murata Manufacturing Co., Ltd. | Apparatus for measuring resistance of electronic component |
WO2003010546A1 (en) * | 2001-07-25 | 2003-02-06 | Tokyo Weld Co., Ltd. | Capacitor insulation resistance measuring method and insulation resistance measuring instrument |
JP2014228452A (en) * | 2013-05-24 | 2014-12-08 | 株式会社エーディーシー | Measuring device |
-
1990
- 1990-09-25 JP JP25467490A patent/JP2949242B2/en not_active Expired - Lifetime
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6127828A (en) * | 1997-05-09 | 2000-10-03 | Murata Manufacturing Co., Ltd. | Apparatus for measuring resistance of electronic component |
WO2003010546A1 (en) * | 2001-07-25 | 2003-02-06 | Tokyo Weld Co., Ltd. | Capacitor insulation resistance measuring method and insulation resistance measuring instrument |
US6642721B2 (en) | 2001-07-25 | 2003-11-04 | Tokyo Weld Co., Ltd. | Method of measuring insulation resistance of capacitor and insulation resistance measuring apparatus of the same |
JP2014228452A (en) * | 2013-05-24 | 2014-12-08 | 株式会社エーディーシー | Measuring device |
Also Published As
Publication number | Publication date |
---|---|
JP2949242B2 (en) | 1999-09-13 |
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