JPH0125332Y2 - - Google Patents
Info
- Publication number
- JPH0125332Y2 JPH0125332Y2 JP1980125645U JP12564580U JPH0125332Y2 JP H0125332 Y2 JPH0125332 Y2 JP H0125332Y2 JP 1980125645 U JP1980125645 U JP 1980125645U JP 12564580 U JP12564580 U JP 12564580U JP H0125332 Y2 JPH0125332 Y2 JP H0125332Y2
- Authority
- JP
- Japan
- Prior art keywords
- resistance
- switch
- replacement
- group
- voltmeter
- 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.)
- Expired
Links
- 238000009413 insulation Methods 0.000 claims description 29
- 238000005259 measurement Methods 0.000 claims description 21
- 238000006467 substitution reaction Methods 0.000 claims 1
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
Description
本考案は使用状態下にある直流電気回路の絶縁
抵抗を短時間に安全確実に測定できる絶縁抵抗測
定装置に関するものである。
従来直流電気回路の絶縁抵抗の測定は、当該電
気回路を含む装置の電源を断とし無電圧状態とし
て抵抗測定器で測定するという方法によつてい
た。しかし近年各装置のシステム化が進行する情
勢の許で、その中心的な要素である電気回路を絶
縁抵抗測定のたび毎に停止状態とすることは、そ
れがシステム全体の停止をともなうことから好ま
しくない。
そこで本考案者は電圧印加状態下にある直流電
気回路の絶縁抵抗を短時間で測定できる方法を発
明した（特願昭55―3480号）。
この方法は直流電気回路の任意の測定点と接地
極との間に抵抗値の異なる２つの置換抵抗をそれ
ぞれ切替可能に挿入し、それぞれの抵抗を挿入し
た回路の漏洩電圧e1，e2を測定し、それらの偏差
値から当該直流電気回路の絶縁抵抗を測定するも
のである。
しかし、この方法は実際には測定点２点間の測
定電圧に基づいて偏差係数を演算し、換算曲線に
よつて当該電気回路の絶縁抵抗値を知るという方
法によつているため、測定には測定電圧の読取、
偏差係数の演算および換算曲線による換算作業が
伴なう。
本考案は上記方法の簡易化による普及の拡大を
計ろうとするもので、予め漏洩電圧e1，e2に対応
する絶縁抵抗を曲線で描いた目盛フイルムを電圧
計に変位可能に装着することによつて被測定直流
電気回路の絶縁抵抗を１目で直読できるようにし
て、上述した測定電圧の読取、偏差係数の演算お
よび換算曲線による換算作業を不要とするととも
に置換抵抗回路および電圧測定範囲を定める分圧
器を複数並列に設けて、絶縁抵抗の測定範囲の拡
大と精度の向上を計ろうとするものである。
本考案を第１図〜第４図に示す実施例に従つて
説明する。
２，２は測定端子で、測定端子２，２には被測
定直流電気回路の測定点が接続される。測定端子
２，２に並列に切替スイツチSW1およびSW2を介
して置換抵抗R1群およびR2群を接続する。スイ
ツチSW1は置換抵抗R1群とR2群との切替用スイ
ツチであり、スイツチSW2はたとえばR1群の抵
抗R1′とR2群の抵抗R2′から抵抗R1″と抵抗R2″…
…抵抗R1 nと抵抗R2 nへと切替える切替用スイツ
チである。
上記各抵抗の抵抗値は、R1′：R2′＝R1″：R2″＝
R1：R2＝R1 n：R2 nのごとく設定される。
上記回路に、点線で囲んで１として示した直流
電圧測定回路を並列接続する。r1〜roはスイツチ
SW3によつて切替可能な分圧器であり、V1は電
圧計である。なおｒは被測定直流電気回路の絶縁
抵抗、Ｄは目盛フイルムを変位するためのダイヤ
ルツマミである。
第１図の状態からスイツチSW1をR1側に倒す
ことによつて電圧計V1に表われる漏洩電圧をe1，
R2側に倒すことによつて電圧計V1に表れる漏洩
電圧をe2とし、直流電圧測定回路１の内部抵抗を
無限大とすると、e1，e2の編差係数ｎは次式で表
わされる。
ｎ＝e1／e2＝R1（ｒ＋R2）／R2（ｒ＋R1） ……(1)
又絶縁抵抗ｒは次式で表わされる。
ｒ＝（ｎ−１）R1／R1／R2−ｎ ……(2)
説明の便のため、R1抵抗群では置換抵抗
R1″を、又R2抵抗群では置換抵抗R2″を選択し、
R1″が11MΩ，R2″が1MΩとし、スイツチSW3の
分圧器r1〜ro 1′の選択によつて定まる直流電圧測
定回路１の電圧測定レンジが30Vであるとした場
合、被測定電気回路の絶縁抵抗ｒに対応する編差
係数ｎおよび漏洩電圧e2に対応するe1の値は第３
図のとおりとなる。第４図には第３図における漏
洩電圧e1，e2に対応する絶縁抵抗ｒを曲線で描い
た目盛フイルム３が示されている。この目盛フイ
ルム３における絶縁抵抗ｒは測定レンジが30Vの
場合のe1，e2から得ているが、抵抗群R1のR1′〜
R1 nおよび抵抗群R2のR2のR2′〜R2 nとの選択組合
せおよびそれぞれの抵抗値は前述したように設定
されているので、直流電圧測定回路１の内部抵抗
が不変である限り偏差係数ｎは常に一定であるの
で、同じ目盛フイルムから、絶縁抵抗ｒの値を
R1群とR2群の組合わされた置換抵抗の設定抵抗
値の倍率で読むことができる。
もし、R1′の抵抗値を22MΩ，R2′のそれを
2MΩ，ｒを18MΩとすると、ｎ＝5.5，又R1″の抵
抗値を11MΩ，R2″のそれを1MΩ，ｒを9MΩとす
ると、(1)式からｎ＝5.5，R1の抵抗値を1.1MΩ，
R2のそれを0.1MΩ，ｒを0.9MΩとすると、ｎ
＝5.5でR1とR2の抵抗値の比が一定であればｎは
常に一定である。又上述した３つの場合における
数値を(2)式に代入すると、第１の場合にはｒ＝
18MΩ、第２の場合にはｒ＝9MΩ、第３の場合
にはｒ＝0.9MΩであり、ｒはR1，R2の設定抵抗
値の倍率として表わされる。
従つて、たとえば第１表に示すごとく諸元を設
定することによつて絶縁抵抗の測定範囲の拡大と
その精度の向上を計ることができる。
The present invention relates to an insulation resistance measuring device that can safely and reliably measure the insulation resistance of a DC electric circuit under use in a short period of time. Conventionally, the insulation resistance of a DC electric circuit has been measured by turning off the power to a device including the electric circuit and measuring it with a resistance meter in a no-voltage state. However, in recent years, as the systemization of various devices has progressed, it is preferable to stop the electrical circuit, which is the central element, every time an insulation resistance measurement is performed, as this would involve stopping the entire system. do not have. Therefore, the present inventor invented a method that can quickly measure the insulation resistance of a DC electric circuit under voltage application (Japanese Patent Application No. 3480/1983). In this method, two replacement resistors with different resistance values are inserted switchably between an arbitrary measurement point in a DC electric circuit and the ground electrode, and the leakage voltages e 1 and e 2 of the circuit in which each resistor is inserted are calculated. The insulation resistance of the DC electric circuit is determined from the deviation values. However, this method actually involves calculating the deviation coefficient based on the measured voltage between two measurement points, and determining the insulation resistance value of the electric circuit from the conversion curve. reading the measured voltage,
This involves calculating the deviation coefficient and converting using a conversion curve. The present invention aims to expand the popularity of the above method by simplifying it, and a scale film on which the insulation resistance corresponding to the leakage voltages e 1 and e 2 is drawn as a curved line is attached in advance to the voltmeter so that it can be displaced. Therefore, the insulation resistance of the DC electric circuit to be measured can be directly read at a glance, thereby eliminating the need for reading the measured voltage, calculating the deviation coefficient, and converting using a conversion curve, as well as eliminating the need for the replacement resistance circuit and voltage measurement range. The aim is to expand the measurement range of insulation resistance and improve accuracy by providing multiple defined voltage dividers in parallel. The present invention will be explained according to the embodiments shown in FIGS. 1 to 4. Reference numerals 2 and 2 indicate measurement terminals, and measurement points of the DC electric circuit to be measured are connected to the measurement terminals 2 and 2. Replacement resistors R 1 group and R 2 group are connected in parallel to measurement terminals 2 and 2 via changeover switches SW 1 and SW 2. The switch SW 1 is a switch for switching between the replacement resistors R 1 group and R 2 group, and the switch SW 2 switches between the resistor R 1 ′ of the R 1 group and the resistor R 2 ′ of the R 2 group, and the resistor R 1 ″. R2 ″…
...This is a switch for switching between resistor R 1 n and resistor R 2 n . The resistance value of each resistor above is R 1 ′: R 2 ′= R 1 ″: R 2 ″=
It is set as R 1 :R 2 =R 1 n :R 2 n . A DC voltage measuring circuit indicated as 1 surrounded by a dotted line is connected in parallel to the above circuit. r 1 ~ r o is a switch
It is a voltage divider switchable by SW 3 and V 1 is a voltmeter. Note that r is the insulation resistance of the DC electric circuit to be measured, and D is a dial knob for displacing the scale film. From the state shown in Figure 1, by turning switch SW 1 to R 1 side, the leakage voltage appearing on voltmeter V 1 is e 1 ,
Assuming that the leakage voltage that appears on the voltmeter V 1 by turning it to the R 2 side is e 2 and that the internal resistance of the DC voltage measurement circuit 1 is infinite, the difference coefficient n of e 1 and e 2 is given by the following formula. expressed. n=e 1 /e 2 =R 1 (r+R 2 )/R 2 (r+R 1 )...(1) Insulation resistance r is expressed by the following formula. r=(n-1)R 1 /R 1 /R 2 -n ...(2) For convenience of explanation, in the R 1 resistance group, replacement resistance
R 1 ″, and for the R 2 resistance group, select the replacement resistor R 2 ″,
Assuming that R 1 ″ is 11MΩ, R 2 ″ is 1MΩ, and the voltage measurement range of DC voltage measurement circuit 1 is 30V, which is determined by the selection of voltage divider r 1 to r o 1 ′ of switch SW 3 . The difference coefficient n corresponding to the insulation resistance r of the measured electric circuit and the value e 1 corresponding to the leakage voltage e 2 are the third
As shown in the diagram. FIG. 4 shows the scale film 3 on which the insulation resistance r corresponding to the leakage voltages e 1 and e 2 in FIG. 3 is drawn as a curve. The insulation resistance r in this scale film 3 is obtained from e 1 and e 2 when the measurement range is 30V, but R 1 ′ to R 1 of the resistance group R 1
Since the selected combinations of R 1 n and R 2 ′ to R 2 n of R 2 of the resistance group R 2 and their respective resistance values are set as described above, the internal resistance of the DC voltage measurement circuit 1 remains unchanged. Since the deviation coefficient n is always constant as long as it is, we can calculate the value of insulation resistance r from the same scale film.
It can be read as a multiplier of the set resistance value of the combined replacement resistance of R1 group and R2 group. If the resistance value of R 1 ′ is 22MΩ and that of R 2 ′ is
2MΩ, r is 18MΩ, n = 5.5, and the resistance value of R 1 ″ is 11MΩ, that of R 2 ″ is 1MΩ, r is 9MΩ, then from equation (1), n = 5.5, the resistance value of R 1 1.1MΩ,
If that of R 2 is 0.1MΩ and r is 0.9MΩ, then n
=5.5 and if the ratio of the resistance values of R 1 and R 2 is constant, n is always constant. Furthermore, when the numerical values in the three cases mentioned above are substituted into equation (2), in the first case, r=
18 MΩ, in the second case r=9 MΩ, and in the third case r=0.9 MΩ, where r is expressed as a multiplier of the set resistance values of R 1 and R 2 . Therefore, by setting the specifications as shown in Table 1, for example, it is possible to expand the measurement range of insulation resistance and improve its accuracy.
【表】
第４図に示す目盛フイルム３を第２図ｂに示す
ごとく、駆動歯車４、回転ドラム６，６の、それ
ぞれの外周の一部に接するようにエンドレスに掛
け、それを電圧計V1の裏側に装着する。１方、
電圧計V1の目盛板７には指示計９が振れる円弧
に沿つた円弧状ののぞき穴８を形成して目盛フイ
ルム３の絶縁抵抗を示す曲線部分ｒが正面から直
読できるようにする。この場合、電圧計V1の目
盛板７はそのまゝ使用できるように上記のぞき穴
８を形成する。
このような構成において、まづ、被測定電気回
路の予想測定電圧e1に従がい、スイツチSW3によ
つてr1〜roのうちの適当な分圧器を選択するとと
もに予想測定絶縁抵抗値ｒに従がい、スイツチ
SW2によつてR1群とR2群のうちの適当な置換抵
抗の組合わせを選択した後、端子２，２に被測定
電気回路の測定点を接続する。
上記の場合、スイツチSW3による分圧器の選択
によつて測定電圧のレンジが定まるので、表示電
圧e1の指示角が大きくなるように分圧器を選ぶ方
が測定精度が高くなるという意味で好ましく、又
スイツチSW2によるR1群とR2群の置換抵抗の組
合せの選定によつてe1とe2の指示角の開きが定ま
るので、e1とe2の指示角の開きが大きくなるよう
に選ぶ方が上述したと同様の理由によつて好まし
い。
上記のように設定した後スイツチSW1を置換抵
抗R2群側に倒すと、電圧計V1にe2が表示される。
しかる後、ダイヤルツマミＤを所定方向へ回動
することによつて駆動歯車４は所定方向へ回転
し、目盛フイルム３は回転ドラム６，６の外周の
一部に沿つて回動する。指示針９の指示位置と目
盛フイルムの、第４図に示す絶縁抵抗の基線
r0MΩの一部が重つたことを、のぞき穴８を介し
て確認したら、目盛フイルム３の回動を停止さ
せ、しかる後、スイツチSW1を置換抵抗R1群側
に切替える。それによつて電圧計V1にはe1が表
示されるが、同時に指示針９は、のぞき穴８の裏
側の目盛フイルム３の絶縁抵抗、すなわち、被測
定電気回路の絶縁抵抗を指示する。なお、１０は
のぞき穴８に張付けた透明板の線で指示針９と絶
縁抵抗との照合用基準線である。
本考案によれば使用状態又は電圧印加状態下に
ある直流電気回路の絶縁抵抗を、測定電圧の読
取、偏差係数の演算および換算曲線の換算等の複
雑な操作をすることなく、きわめて簡易な構成で
直読可能としたもので、これを一般の小型直流電
圧計、回路計等に付加することによつて本書冒頭
において述べたような問題点を容易に解決でき
る。[Table] As shown in FIG. 2b, the scale film 3 shown in FIG. Attach to the back side of 1 . One side,
An arc-shaped peephole 8 is formed in the scale plate 7 of the voltmeter V1 along the arc in which the indicator 9 swings, so that the curved part r indicating the insulation resistance of the scale film 3 can be read directly from the front. In this case, the scale plate 7 of the voltmeter V1 forms the above-mentioned peephole 8 so that it can be used as is. In such a configuration, first, according to the expected measured voltage e 1 of the electric circuit to be measured, an appropriate voltage divider from r 1 to r o is selected by switch SW 3 , and the expected measured insulation resistance value is selected. follow r, switch
After selecting an appropriate combination of replacement resistors from the R1 group and the R2 group using SW 2 , the measurement points of the electrical circuit to be measured are connected to the terminals 2, 2. In the above case, the measurement voltage range is determined by the voltage divider selected by switch SW 3 , so it is preferable to select a voltage divider that increases the indication angle of display voltage e 1 in the sense that measurement accuracy will be higher. Also, the difference in the indicated angles of e 1 and e 2 is determined by the selection of the combination of replacement resistors of the R 1 group and R 2 group by switch SW 2 , so the difference in the indicated angles of e 1 and e 2 becomes larger. It is preferable to select as follows for the same reason as mentioned above. After setting as above, when switch SW 1 is moved to the side of replacement resistor R 2 group, e 2 will be displayed on voltmeter V 1 . Thereafter, by rotating the dial knob D in a predetermined direction, the drive gear 4 is rotated in a predetermined direction, and the scale film 3 is rotated along a part of the outer periphery of the rotating drums 6, 6. The indicated position of the indicator needle 9 and the base line of the insulation resistance of the scale film shown in Fig. 4
When it is confirmed through the peephole 8 that a part of r0MΩ has become heavy, the rotation of the scale film 3 is stopped, and then the switch SW 1 is switched to the side of the replacement resistor R 1 group. As a result, e1 is displayed on the voltmeter V1 , but at the same time, the indicator needle 9 indicates the insulation resistance of the scale film 3 on the back side of the peephole 8, that is, the insulation resistance of the electrical circuit to be measured. Note that 10 is a line on a transparent plate attached to the peephole 8 and is a reference line for checking the indicator needle 9 and the insulation resistance. According to the present invention, the insulation resistance of a DC electric circuit in use or under voltage application can be determined with an extremely simple configuration without having to perform complicated operations such as reading measured voltage, calculating deviation coefficients, and converting conversion curves. By adding this to general small DC voltmeters, circuit meters, etc., the problems mentioned at the beginning of this book can be easily solved.
第１図は本考案の実施例を示す回路図、第２図
ａは本考案の機構例を示す正面図、第２図ｂは第
２図ａの指示計部の側面図、第３図は被測定電気
回路の絶縁抵抗に対応する編差係数および漏洩電
圧e2に対するe1の値を示す図表、第４図は第２図
ａにおける指示計部と目盛フイルムとの位置的関
係を示す正面図である。
２，２……測定端子、３……目盛フイルム、８
……電圧計のぞき穴、R1，R2……置換抵抗、ｒ
……絶縁抵抗、r1〜ro，SW3……電圧測定範囲切
替回路、SW1，SW2……切替スイツチ、V1……
直流電圧計。
Fig. 1 is a circuit diagram showing an embodiment of the invention, Fig. 2a is a front view showing an example of the mechanism of the invention, Fig. 2b is a side view of the indicator section of Fig. 2a, and Fig. 3 is a A chart showing the deviation coefficient corresponding to the insulation resistance of the electrical circuit to be measured and the value of e 1 against the leakage voltage e 2. Figure 4 is a front view showing the positional relationship between the indicator section and the scale film in Figure 2 a. It is a diagram. 2, 2...Measuring terminal, 3...Graduation film, 8
...Voltmeter peephole, R 1 , R 2 ...Replacement resistance, r
... Insulation resistance, r 1 ~ r o , SW 3 ... Voltage measurement range switching circuit, SW 1 , SW 2 ... Selector switch, V 1 ...
DC voltmeter.
Claims (1)
した置換抵抗群R1とR2とをそれぞれ切替スイツ
チSW1およびSW2を介して測定端子間に接続し、
上記一方の置換抵抗群R1を構成する、それぞれ
の抵抗と、それに対応する、他方の置換抵抗群
R2を構成するそれぞれの抵抗との抵抗比がそれ
ぞれ同一であるように設定し、上記切替スイツチ
SW1は上記置換抵抗群R1とR2との切替を、又切
替スイツチSW2は置換抵抗群R1を構成する抵抗
間、および置換抵抗群R2を構成する抵抗間の切
替えをするように設定し、上記切替スイツチSW1
のマイナス側に、並列接続された抵抗群と当該抵
抗群を構成する抵抗間の切替をする切替スイツチ
SW3とからなる分圧器、ついで直流電圧計を接続
し、上記切替スイツチSW3による上記分圧抵抗間
における切替えによつて定まる電圧測定範囲にお
ける、上記切替スイツチSW1，SW2による、置換
抵抗群R1又はR2を構成する抵抗間の切替えによ
つて定まる、置換抵抗に基づく被測定電気回路の
絶縁抵抗を曲線で描いた目盛フイルムを回転自由
に回転ドラム間にエンドレスに掛けて、直流電圧
計の裏側に装着し、上記直流電圧計の目盛板には
指示針が振れる円弧に沿つた円弧状ののぞき穴を
形成して、上記目盛フイルム３の絶縁抵抗を示す
曲線が直流電圧計の正面から直視できるように設
定したことからなる使用状態下にある直流回路の
絶縁抵抗測定装置。 Replacement resistance groups R 1 and R 2 , which are resistances having different resistance values connected in parallel, are connected between measurement terminals via changeover switches SW 1 and SW 2 , respectively.
Each of the resistors forming one of the above-mentioned replacement resistance groups R 1 and the corresponding other replacement resistance group
Set the resistance ratio with each resistor that makes up R 2 to be the same, and turn the above selector switch.
SW 1 is used to switch between the replacement resistance groups R 1 and R 2 , and switch SW 2 is used to switch between the resistances that make up the replacement resistance group R 1 and between the resistances that make up the replacement resistance group R 2 . and set the above selector switch SW 1
On the negative side of the switch, there is a switch that switches between the resistor group connected in parallel and the resistors that make up the resistor group.
A voltage divider consisting of SW 3 and then a DC voltmeter are connected, and the changeover switch SW 1 and SW 2 provide a replacement resistor group in a voltage measurement range determined by switching between the voltage dividing resistors by the changeover switch SW 3 . A scale film with a curved line representing the insulation resistance of the electrical circuit to be measured based on the substitution resistance, determined by switching between the resistors composing R 1 or R 2 , is hung endlessly between the rotating drums, and a DC voltmeter is measured. The scale plate of the DC voltmeter has an arc-shaped peephole along the arc in which the indicator needle swings, so that the curve indicating the insulation resistance of the scale film 3 can be seen directly from the front of the DC voltmeter. A device for measuring insulation resistance of a DC circuit under operating conditions, configured as follows.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1980125645U JPH0125332Y2 (en) | 1980-09-05 | 1980-09-05 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1980125645U JPH0125332Y2 (en) | 1980-09-05 | 1980-09-05 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5748464U JPS5748464U (en) | 1982-03-18 |
| JPH0125332Y2 true JPH0125332Y2 (en) | 1989-07-28 |
Family
ID=29486112
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1980125645U Expired JPH0125332Y2 (en) | 1980-09-05 | 1980-09-05 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0125332Y2 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5540939A (en) * | 1978-09-15 | 1980-03-22 | Matsushita Electric Works Ltd | Impedance measuring unit |
-
1980
- 1980-09-05 JP JP1980125645U patent/JPH0125332Y2/ja not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5540939A (en) * | 1978-09-15 | 1980-03-22 | Matsushita Electric Works Ltd | Impedance measuring unit |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5748464U (en) | 1982-03-18 |
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