JPS60247119A - Calibrating device for converter of electromagnetic flowmeter - Google Patents
Calibrating device for converter of electromagnetic flowmeterInfo
- Publication number
- JPS60247119A JPS60247119A JP59102702A JP10270284A JPS60247119A JP S60247119 A JPS60247119 A JP S60247119A JP 59102702 A JP59102702 A JP 59102702A JP 10270284 A JP10270284 A JP 10270284A JP S60247119 A JPS60247119 A JP S60247119A
- Authority
- JP
- Japan
- Prior art keywords
- converter
- terminals
- voltage
- electromagnetic flowmeter
- output
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/56—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using electric or magnetic effects
- G01F1/58—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using electric or magnetic effects by electromagnetic flowmeters
- G01F1/60—Circuits therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F25/00—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
- G01F25/10—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Details Of Flowmeters (AREA)
- Measuring Volume Flow (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は、電磁流量計変換器の校正装置に関するもので
ある。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a calibration device for an electromagnetic flowmeter converter.
一般に電磁流量計は、第１図に示すように、検出器２と
変換器４とから構成されている。Generally, an electromagnetic flowmeter is composed of a detector 2 and a converter 4, as shown in FIG.
検出器２は、検出器配管６及び励磁コイル８を主な構成
要素とする。６ａ、６ｂは、いずれも検出器配管６に設
けられた電極である。１０ａ、１０ｂ、１０ｃは検出器
信号出力端子であり、出力端子１０ａおよび１０ｂはそ
れぞれ電極６ａおよび６ｂに接続されており、出力端子
１０ｃは接地されている。１２ａおよび１２ｂは励磁電
流の入力端子であり、励磁コイル８の両端に接続されて
いる。The main components of the detector 2 are a detector pipe 6 and an excitation coil 8. 6a and 6b are both electrodes provided in the detector piping 6. 10a, 10b, and 10c are detector signal output terminals, and the output terminals 10a and 10b are connected to electrodes 6a and 6b, respectively, and the output terminal 10c is grounded. 12a and 12b are excitation current input terminals, which are connected to both ends of the excitation coil 8.
変換器４は、検出器信号増幅部１４．励磁電流発生部１
６およびタイミング信号発生部１８を主な構成要素とす
る。The converter 4 includes a detector signal amplification section 14. Excitation current generator 1
6 and a timing signal generator 18 as the main components.
検出器信号増幅部１４は、増幅器２０ａ〜２０ｅ、抵抗
２２ａおよび２２ｂ、スイッチ２４ａおよび２４ｂ、コ
ンデンサ２６ａおよび２６ｂを含む。励磁電流発生部１
６は、定電流電源２８およびスイッチ３０ａ〜３０ｄを
含む。タイミング信号発生部１８は、マイクロコンピュ
ータ３２を含み、スイッチ２４ａ、２４ｂ、３（ｌａ′
＝３０ｄの切換制御を行っている。なお、３４はインタ
ーフェースである。Detector signal amplification section 14 includes amplifiers 20a to 20e, resistors 22a and 22b, switches 24a and 24b, and capacitors 26a and 26b. Excitation current generator 1
6 includes a constant current power supply 28 and switches 30a to 30d. The timing signal generator 18 includes a microcomputer 32, and switches 24a, 24b, 3 (la'
=30d switching control is performed. Note that 34 is an interface.
３６は増幅器２０ｅの出力するアナログ信号をディジタ
ル信号に変換するＡ−Ｄ変換器である。36 is an AD converter that converts the analog signal output from the amplifier 20e into a digital signal.
３８ａ〜３８Ｃは検出器出力の入力端子であり出力端子
１０８〜ＩＯＣと接続し、４０ａおよび４０ｂは励磁電
流の出力端子であり入力端子１２ａおよび１２ｂと接続
している。38a to 38C are input terminals for detector output and are connected to output terminals 108 to IOC, and 40a and 40b are output terminals for excitation current and are connected to input terminals 12a and 12b.
ところで、電磁流量計の変換器は一般に校正を行なう必
要がある。すなわち、所定の入出力関係を満足するよう
に該変換器を調整する必要がある。By the way, the converter of an electromagnetic flowmeter generally needs to be calibrated. That is, it is necessary to adjust the converter so as to satisfy a predetermined input/output relationship.
たとえば、第１図において、入力端子３８ａ〜３８Ｃに
１ｍＶの電圧の信号を与えた時に、増幅器２０ｅに４ｍ
Ａの出力が出るように検出器信号増幅部１４の各素子を
調整する。For example, in FIG. 1, when a voltage signal of 1 mV is applied to the input terminals 38a to 38C, the amplifier 20e is supplied with a voltage of 4 mV.
Each element of the detector signal amplification section 14 is adjusted so that an output of A is output.
ところが、検出器信号のタイミングを決定するところの
励磁コイルの励磁方式には種々の方式が考えられている
。第２図は種々の励磁電流波形を示すタイミングチャー
トであり、（ａ、 ）および（ｂ）は両極性励磁方式の
励磁電流波形を示し、（Ｃ）は片極性励磁方式の励磁電
流波形を示す。However, various methods have been considered for the excitation method of the excitation coil that determines the timing of the detector signal. Fig. 2 is a timing chart showing various exciting current waveforms, (a, ) and (b) show the exciting current waveform of the bipolar excitation method, and (C) shows the exciting current waveform of the unipolar excitation method. .
変換器の校正を正確に行なうためには、実際に用いる励
磁方式のタイミングに合わせて基準電圧の信号を与える
必要がある。そのため、従来の校正装置では、変換器の
タイミング信号発生部から信号をもらい、該信号をデコ
ードして校正用の基準電圧信号を発生していた。したが
って、変換器の励磁方式が異なれば、それに応じた校正
装置が必要であった。In order to accurately calibrate the converter, it is necessary to provide a reference voltage signal in accordance with the timing of the excitation method actually used. Therefore, in the conventional calibration device, a signal is received from a timing signal generating section of a converter, and the signal is decoded to generate a reference voltage signal for calibration. Therefore, if the excitation method of the converter differs, a corresponding calibration device is required.
本発明は、上記問題点に鑑みてなされたものであり、そ
の目的とするところは、電磁流量計変換器が如何なる励
磁方式であっても校正試験をすることのできる校正装置
を提供することにある。The present invention has been made in view of the above problems, and its purpose is to provide a calibration device that can perform a calibration test regardless of the excitation method of an electromagnetic flowmeter converter. be.
かかる目的を達成するために本発明は、電磁流量計変換
器からの励磁電流を入力してこの励磁電流の方向を判別
し、この判別結果に応じて校正用の基準電圧信号を電磁
流量計変換器の入力端子に与えるようにしたものである
。In order to achieve such an object, the present invention inputs an excitation current from an electromagnetic flowmeter converter, determines the direction of this excitation current, and converts a reference voltage signal for calibration into an electromagnetic flowmeter converter according to the determination result. It is designed to be applied to the input terminal of the device.
以下、実施例と共に本発明の詳細な説明する。Hereinafter, the present invention will be described in detail along with examples.
第３図は、本発明の一実施例を示すブロック図である。 FIG. 3 is a block diagram showing one embodiment of the present invention.
５０ａ、５０ｂは電磁流量計変換器が出力する励磁電流
を入力する入力端子であり、入力端子５０ａは作動増幅
器５２のプラス入力端子に接続され、入力端子５０ｂは
作動増幅器５４のプラス入力端子に接続されている。作
動増幅器５２および５４のマイナス入力端子はいずれも
定電圧直流電源５６を介して接地されている。作動増幅
器５２および５４のプラス入力端子間には抵抗値Ｒの抵
抗５８が接続されている。これら作動増幅器５２、作動
増幅器５４．定電圧直流電源５６および抵抗５８は、励
磁電流の方向およびタイミングを判別する励磁電流判別
手段６０を構成している。50a and 50b are input terminals for inputting the excitation current output by the electromagnetic flowmeter converter, the input terminal 50a is connected to the positive input terminal of the operational amplifier 52, and the input terminal 50b is connected to the positive input terminal of the operational amplifier 54. has been done. The negative input terminals of operational amplifiers 52 and 54 are both grounded via a constant voltage DC power supply 56. A resistor 58 having a resistance value R is connected between the positive input terminals of operational amplifiers 52 and 54. These operational amplifiers 52, 54. The constant voltage DC power supply 56 and the resistor 58 constitute excitation current determining means 60 that determines the direction and timing of the excitation current.
作動増幅器５２および５４の出力線６２および６４はそ
れぞれスイッチ６６および６８の切換入力端子に接続さ
れている。スイッチ６６および６８は、後述する基準電
圧源８０から出力端子９０ａ〜９０ｃへの電圧供給を切
換制御するスイッチング手段７０を構成している。Output lines 62 and 64 of differential amplifiers 52 and 54 are connected to switching input terminals of switches 66 and 68, respectively. The switches 66 and 68 constitute a switching means 70 that switches and controls voltage supply from a reference voltage source 80 to the output terminals 90a to 90c, which will be described later.
８２は、電圧値を任意に設定することができる直流電源
であり、マイマス側は接地され、プラス側はスイッチ６
６の一方の端子および極性反転器８４の入力端子に接続
されている。極性反転器８４は入力電圧と異なる極性の
電圧を入力電圧値に応じて出力するものであり、その出
力端子はスイッチ６８の一方の端子に接続されている。82 is a DC power supply whose voltage value can be set arbitrarily, the main side is grounded, and the positive side is connected to switch 6.
6 and an input terminal of a polarity inverter 84. The polarity inverter 84 outputs a voltage with a polarity different from the input voltage according to the input voltage value, and its output terminal is connected to one terminal of the switch 68.
スイッチ６６の他方の端子と直流電源８２のマイナス側
との間には抵抗値ｒの抵抗８６が挿入され、同様に、ス
イッチ６８の他方の端子と直流電源８２のマイナス側と
の間には抵抗値ｒの抵抗８８が挿入されている。なお、
直流電源８２．極性反転器８４．抵抗８６．８８は基準
電圧源８０を構成している。A resistor 86 with a resistance value r is inserted between the other terminal of the switch 66 and the negative side of the DC power source 82, and similarly, a resistor 86 is inserted between the other terminal of the switch 68 and the negative side of the DC power source 82. A resistor 88 of value r is inserted. In addition,
DC power supply 82. Polarity inverter 84. Resistors 86 and 88 constitute a reference voltage source 80.
９０８〜９０Ｃは、出力端子であり、電磁流量計変換器
の検出器信号入力端子に接続されるものである。908 to 90C are output terminals, which are connected to the detector signal input terminal of the electromagnetic flowmeter converter.
次に、本実施例の動作を説明す条。Next, there will be a section explaining the operation of this embodiment.
入力端子５０ａ、５０ｂを電磁流量計変換器の励磁電流
出力端子（第１図４０８，４０ｂ）に接続し、出力端子
９０３〜９０Ｃを同じく電磁流量計変換器の検出器信号
入力端子（第１図３８ａ〜３８ｂ）に接続する。The input terminals 50a and 50b are connected to the excitation current output terminals (408, 40b in Fig. 1) of the electromagnetic flowmeter converter, and the output terminals 903 to 90C are connected to the detector signal input terminals of the electromagnetic flowmeter converter (Fig. 1). 38a-38b).
かかる状態で、変換器から第４図（ａ）に示すような両
極性励磁電流を入力端子５Ｑａ、５０ｂに供給すると、
出力線６２および出力線６４にはそれぞれ第４図（ｂ）
および（Ｃ）に示すような信号が得られる。すなわち、
励磁電流の方向がＸ方向（波形ａ）の時は作動増幅器５
２の出力信号が論理値“１”となり、励磁電流の方向が
Ｙ方向（波形ｂ）の時は作動増幅器５４の出力信号が論
理値“１”となり、励磁電流が零（波形Ｃ）の時は作動
増幅器５２．５４いずれも論理値“０”が保持されたま
まとなる。In this state, when a bipolar excitation current as shown in FIG. 4(a) is supplied from the converter to the input terminals 5Qa and 50b,
The output line 62 and the output line 64 are each shown in FIG. 4(b).
And a signal as shown in (C) is obtained. That is,
When the direction of the excitation current is the X direction (waveform a), the operational amplifier 5
When the output signal of the differential amplifier 54 has a logical value of "1" and the direction of the excitation current is in the Y direction (waveform b), the output signal of the operational amplifier 54 has a logical value of "1", and when the excitation current is zero (waveform C) The operational amplifiers 52 and 54 both maintain the logic value "0".
作動増幅器５２の出力論理値が“１”となるとスイッチ
６６が閉じ、直流電源８２によって抵抗８６の両端に校
正用の基準電圧が生じる。この電圧は出力端子９０ａ、
９０ｃ間に現れ、電磁流量計変換器の検出器信号入力端
子に与えられる。同様に、作動増幅器５４の出力論理値
が“１”となるとスイッチ６８が閉じ、直流電源８２お
よび極性反転器８４によって抵抗８８の両端に逆極性の
校正用基準電圧が生じる。この電圧は出力端子９０ｂ、
９０ｃ間に現れ、電磁流量計変換器の検出器信号入力端
子に与えられる。When the output logic value of the operational amplifier 52 becomes "1", the switch 66 is closed, and a reference voltage for calibration is generated across the resistor 86 by the DC power supply 82. This voltage is applied to the output terminal 90a,
90c and is applied to the detector signal input terminal of the electromagnetic flowmeter converter. Similarly, when the output logic value of the operational amplifier 54 becomes "1", the switch 68 is closed, and a calibration reference voltage of opposite polarity is generated across the resistor 88 by the DC power supply 82 and the polarity inverter 84. This voltage is applied to the output terminal 90b,
90c and is applied to the detector signal input terminal of the electromagnetic flowmeter converter.
励磁電流が第２図（ｃ）に示すような片極性の場合には
、作動増幅器５４の出力は論理値“０”を保持し、作動
増幅器５２の出力は論理値“１”と“０″を繰り返すこ
とになる。When the excitation current is unipolar as shown in FIG. 2(c), the output of the differential amplifier 54 maintains the logic value "0", and the output of the differential amplifier 52 maintains the logic values "1" and "0". will be repeated.
このようにして、変換器の検出器信号入力端子には、実
際の検出器信号と同じタイミングで校正用の検出器信号
が与えられるので、このときの変換器の出力電流（第１
図の増幅器２０ｅの出力）が予め定められた値になるよ
うに変換器の各素子の調整を行なえばよい。In this way, the detector signal for calibration is given to the detector signal input terminal of the converter at the same timing as the actual detector signal, so the output current of the converter at this time (the first
Each element of the converter may be adjusted so that the output (of the amplifier 20e in the figure) becomes a predetermined value.
第５図は他の実施例を示すブロック図である。FIG. 5 is a block diagram showing another embodiment.
なお、同図において、第３図と同一の部分には同一の符
号を付してその詳細な説明を舌略する。In addition, in this figure, the same parts as in FIG. 3 are given the same reference numerals, and detailed explanation thereof will be omitted.
１００は基準電圧源であり、プラス出力端子１０２、マ
イナス出力端子１０４．共通端子１０６を有する。この
基準電圧源１００は指定した電圧値を任意にプラス出力
端子１０２．マイナス出力端子１０４に出力することが
できる。なお、電圧値の指定はディジタル入力式になっ
ている。100 is a reference voltage source, which has a positive output terminal 102, a negative output terminal 104 . It has a common terminal 106. This reference voltage source 100 arbitrarily outputs a specified voltage value to a plus output terminal 102. It can be output to the negative output terminal 104. Note that the voltage value is specified using a digital input method.
スイッチング手段７０の動作は前述の実施例と同様であ
るので説明は省略するが、本実施例においても変換器の
検出器信号入力端子に、実際の検出器信号と同じタイミ
ングで校正用の検出器信号を与えることができる。The operation of the switching means 70 is the same as in the previous embodiment, so a description thereof will be omitted. In this embodiment as well, a calibration detector is connected to the detector signal input terminal of the converter at the same timing as the actual detector signal. can give a signal.
第６図はさらに他の実施例を示すブロック図である。こ
の実施例では第３図の基準電圧源８０とスイッチング手
段７０における動作をマイクロコンピュータ２００によ
るディジタル処理およびＤ／Ａ変換器２０２によるアナ
ログ値への変換によって達成するものであり、基準電圧
値等の必要なデータはキー＆ディスプレイ装置２０４か
ら自由に入力できる。FIG. 6 is a block diagram showing still another embodiment. In this embodiment, the operations of the reference voltage source 80 and the switching means 70 shown in FIG. 3 are achieved by digital processing by the microcomputer 200 and conversion into analog values by the D/A converter 202. Necessary data can be input freely using the key and display device 204.
以上説明したように、本発明の校正装置によれば、電磁
流量計変換器からの励磁電流を入力してこの励磁電流の
方向を判別し、この判別結果に応じて校正用の基準電圧
信号を電磁流量計変換器の入力端子に与えるようにした
ので、電磁流量計変換器が如何なる励磁方式であっても
正確かつ容易に校正試験をすることのできる。As explained above, according to the calibration device of the present invention, the excitation current from the electromagnetic flowmeter converter is input, the direction of this excitation current is determined, and the reference voltage signal for calibration is determined according to the determination result. Since it is applied to the input terminal of the electromagnetic flowmeter converter, a calibration test can be performed accurately and easily regardless of the excitation method of the electromagnetic flowmeter converter.
第１図は一般的な電磁流量計を示すブロック図、第２図
は種々の励磁電流波形を示すタイミングチャート、第３
図は本発明の一実施例を示すブロック図、第４図はその
タイミングチャート、第５図は本発明の他の実施例を示
すブロック図、第６図はさらに別の実施例を示すブロッ
ク図である。
５０ａ、５０ｂ・・・入力端子、６０・・・励磁電流判
別手段、７０・・・スイッチング手段、８０・・・基準
電圧源、９０ａ〜９０Ｃ・・・出力端子。
特許出願人 山武ハネウェル株式会社
代 理 人 山川 政樹（ほか２名）Figure 1 is a block diagram showing a general electromagnetic flowmeter, Figure 2 is a timing chart showing various exciting current waveforms, and Figure 3 is a timing chart showing various exciting current waveforms.
The figure is a block diagram showing one embodiment of the present invention, FIG. 4 is a timing chart thereof, FIG. 5 is a block diagram showing another embodiment of the present invention, and FIG. 6 is a block diagram showing yet another embodiment. It is. 50a, 50b...input terminal, 60...excitation current discrimination means, 70...switching means, 80...reference voltage source, 90a-90C...output terminal. Patent applicant Yamatake Honeywell Co., Ltd. Agent Masaki Yamakawa (and 2 others)
Claims (1)
子と、この入力端子から得られた励磁電流を入力してこ
の励磁電流の方向およびタイミングを判別する励磁電流
判別手段と、電磁流量計変換器の検出器信号入力端子と
接続する出力端子と、この出力端子に任意の電圧を供給
する基準電圧源と、前記励磁電流判別手段の出力信号に
応じて前記基準電圧源から前記出力端子への電圧供給を
切換制御するスイッチング手段とを具備する電磁流量計
変換器の校正装置。an input terminal connected to the excitation current output terminal of the electromagnetic flowmeter converter; an excitation current determination means for inputting the excitation current obtained from the input terminal and determining the direction and timing of the excitation current; and an electromagnetic flowmeter conversion device. an output terminal connected to the detector signal input terminal of the detector; a reference voltage source that supplies an arbitrary voltage to the output terminal; A calibration device for an electromagnetic flow meter converter, comprising switching means for switching and controlling voltage supply.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59102702A JPS60247119A (en) | 1984-05-23 | 1984-05-23 | Calibrating device for converter of electromagnetic flowmeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59102702A JPS60247119A (en) | 1984-05-23 | 1984-05-23 | Calibrating device for converter of electromagnetic flowmeter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60247119A true JPS60247119A (en) | 1985-12-06 |
| JPH0535362B2 JPH0535362B2 (en) | 1993-05-26 |
Family
ID=14334590
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59102702A Granted JPS60247119A (en) | 1984-05-23 | 1984-05-23 | Calibrating device for converter of electromagnetic flowmeter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60247119A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100408986C (en) * | 2005-04-21 | 2008-08-06 | 上海大学 | Tester for electromagnetic flowmeter signal converter |
| US20160116325A1 (en) * | 2014-10-28 | 2016-04-28 | Azbil Corporation | Standard signal generator |
| JP2016085149A (en) * | 2014-10-28 | 2016-05-19 | アズビル株式会社 | Standard signal generator |
| JP2016085148A (en) * | 2014-10-28 | 2016-05-19 | アズビル株式会社 | Standard signal generator |
| CN112229457A (en) * | 2020-11-19 | 2021-01-15 | 吉林大学 | Novel electromagnetic flowmeter and measuring method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5971124U (en) * | 1982-11-05 | 1984-05-15 | 富士電機株式会社 | Calibration device for electromagnetic flowmeter converter |
-
1984
- 1984-05-23 JP JP59102702A patent/JPS60247119A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5971124U (en) * | 1982-11-05 | 1984-05-15 | 富士電機株式会社 | Calibration device for electromagnetic flowmeter converter |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100408986C (en) * | 2005-04-21 | 2008-08-06 | 上海大学 | Tester for electromagnetic flowmeter signal converter |
| US20160116325A1 (en) * | 2014-10-28 | 2016-04-28 | Azbil Corporation | Standard signal generator |
| JP2016085149A (en) * | 2014-10-28 | 2016-05-19 | アズビル株式会社 | Standard signal generator |
| JP2016085150A (en) * | 2014-10-28 | 2016-05-19 | アズビル株式会社 | Standard signal generator |
| JP2016085148A (en) * | 2014-10-28 | 2016-05-19 | アズビル株式会社 | Standard signal generator |
| US10215615B2 (en) * | 2014-10-28 | 2019-02-26 | Azbil Corporation | Standard signal generator |
| CN112229457A (en) * | 2020-11-19 | 2021-01-15 | 吉林大学 | Novel electromagnetic flowmeter and measuring method thereof |
| CN112229457B (en) * | 2020-11-19 | 2021-09-21 | 吉林大学 | Novel electromagnetic flowmeter and measuring method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0535362B2 (en) | 1993-05-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |