JPS5821039Y2 - 2 Senshikidensouki - Google Patents
2 SenshikidensoukiInfo
- Publication number
- JPS5821039Y2 JPS5821039Y2 JP1975176406U JP17640675U JPS5821039Y2 JP S5821039 Y2 JPS5821039 Y2 JP S5821039Y2 JP 1975176406 U JP1975176406 U JP 1975176406U JP 17640675 U JP17640675 U JP 17640675U JP S5821039 Y2 JPS5821039 Y2 JP S5821039Y2
- Authority
- JP
- Japan
- Prior art keywords
- receiving side
- voltage
- information
- transmitter
- transmission line
- 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
Landscapes
- Arrangements For Transmission Of Measured Signals (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Description
【考案の詳細な説明】
この考案は測定量を電気信号に変換し、この変換された
情報信号を離れた受信側に伝送する伝送器（変換器）、
特に測定対象のある場所に配設された伝送器よりの受信
側への情報信号の伝送と、受信側よりの伝送器（変換器
）の、駆動電力の供給とを同一の２線でもって行なうよ
うにした２線式伝送器に関するものである。[Detailed description of the invention] This invention consists of a transmitter (converter) that converts a measured quantity into an electrical signal and transmits this converted information signal to a remote receiving side;
In particular, the transmission of information signals from a transmitter placed at the location of the measurement target to the receiving side and the supply of driving power from the receiving side to the transmitter (converter) are performed using the same two wires. The present invention relates to a two-wire transmitter.
情報信号と電力供給とを同一の２線で行なうようにした
２線式伝送器は測定対象のある場所（以下現場という）
に配設された伝送器と現場より離れた受信側とを２線で
もって接続したもので、定電流特性を有しており、この
特性でもって測定量をそれに比例した直流電流信号に変
換し、それを上記２線の伝送線を介して受信側に伝送す
ると共に受信側より上記伝送線を介して上記伝送器にそ
れの駆動用の定電圧を与えるようにしたもので、現場よ
りの情報信号の伝送と、受信側よりの現場の伝送器への
電力供給を同一の２線で同時に行なうようにしたもので
ある。A two-wire transmitter that uses the same two wires for information signals and power supply is installed at the location where the measurement target is located (hereinafter referred to as the "site").
The transmitter installed at the site and the receiver located far away from the site are connected by two wires, and it has constant current characteristics, and this characteristic allows the measured quantity to be converted into a direct current signal proportional to it. This is transmitted to the receiving side via the above two transmission lines, and the receiving side applies a constant voltage for driving the transmitter to the transmitter via the above transmission line. Signal transmission and power supply from the receiving side to the on-site transmitter are simultaneously carried out over the same two wires.
要するに受信側より供給される一方向の定電圧に伝送器
の定電流特性をミックスしたもので受信側より定電圧を
現場の伝送器に供給し、現場よりの伝送器の定電流特性
により受信側に直流電流出力を情報信号として伝送する
ようにした伝送路回路である。In short, it is a combination of a one-way constant voltage supplied from the receiving side and the constant current characteristics of the transmitter.The receiving side supplies constant voltage to the transmitter at the site, and the constant current characteristics of the transmitter from the site is used to This is a transmission line circuit that transmits direct current output as an information signal.
なお、上記において測定量とは温度・圧力等の測定され
た物理量ないし物理的変数を意味する。In addition, in the above, the measured quantity means a measured physical quantity or physical variable such as temperature and pressure.
近年上記の２線式伝送器においても・、現場よりの受信
側への情報信号の伝送のみならず、現場の伝送器への電
力供給とは別に受信側より現場に各種の指令信号等の情
報を伝送することが必要となり、その伝達情報も多くな
る傾向にある。In recent years, the two-wire transmitters mentioned above not only transmit information signals from the field to the receiving side, but also transmit information such as various command signals from the receiving side to the field, in addition to supplying power to the transmitter at the field. It becomes necessary to transmit information, and the amount of information to be transmitted tends to increase.
このような場合、上記の情報信号の伝送と電力供給とを
同一の２線で行なうようにしたものでは、受信側より現
場に伝送する情報量に応じて伝送線（回線）を増設する
必要があり、そのために多額の費用と労力を必要とする
。In such cases, if the above-mentioned information signal transmission and power supply are carried out over the same two wires, it is necessary to install additional transmission lines (lines) depending on the amount of information to be transmitted from the receiving side to the site. This requires a large amount of money and effort.
また、一般的に多量の情報を伝送する場合、高周波搬送
波で情報を変調して伝送する多重伝送方式が有利であり
、回線の増設を必要とすることなく多量の情報が伝送で
きるものの送受装置に多額の経費がかかると共に伝送線
も、同軸ケーブルとといったような特別な工事となり高
周波伝送によるケーブル損失も問題となる。Additionally, when transmitting a large amount of information, a multiplex transmission method that modulates and transmits the information using a high-frequency carrier wave is generally advantageous, and although it can transmit a large amount of information without the need for additional lines, In addition to requiring a large amount of expense, the transmission line requires special construction such as a coaxial cable, and cable loss due to high frequency transmission becomes a problem.
計装において一般的に取り扱う信号は現場よりの受信側
に伝送される測定量に比例した連続アナログ信号と、受
信側より現場への情報信号としては例えばバルブの開度
制御における警報信号・起動・停止信号といった０Ｎ−
ＯＦＦ信号である。Signals commonly handled in instrumentation are continuous analog signals proportional to the measured quantity that are transmitted from the field to the receiving side, and information signals sent from the receiving side to the field include alarm signals, activation signals, etc. for valve opening control. 0N- such as a stop signal
This is an OFF signal.
したがってこのような現場よりの１つのアナログ連続信
号と受信側よりの各０Ｎ−ＯＦＦ信号を相互に伝送する
ことができ、しかも現場より受信側に伝送されるアナロ
グ連続信号の伝送と同時にそれを切ることなく受信側よ
り各種の０Ｎ−ＯＦＦ情報信号を同一の伝送線を介して
伝送できれば有利であり、このように現場よりの情報信
号の伝送と同時に受信側よりの各種の情報の伝送をも可
能ならしめた２線式伝送器が要望されている。Therefore, one analog continuous signal from the field and each ON-OFF signal from the receiving side can be mutually transmitted, and it can be turned off at the same time as the analog continuous signal transmitted from the field to the receiving side. It would be advantageous if various 0N-OFF information signals could be transmitted from the receiving side via the same transmission line without any interference, and in this way, it would be possible to transmit various information from the receiving side at the same time as transmitting information signals from the field. There is a need for a standardized two-wire transmitter.
この考案は上記に鑑み、現場に配設された伝送器よりの
測定量に比例した情報信号の伝送に使用される２本の伝
送線のみで、受信側より上記伝送器駆動用定電圧の供給
と共に現場よりの情報信号と同時に受信側１よりの情報
を現場に伝送できるようにした２線式伝送器を提供しよ
うとするものである。In view of the above, this idea was developed by using only two transmission lines used to transmit information signals proportional to the measured amount from a transmitter installed at the site, and supplying a constant voltage for driving the transmitter from the receiving side. The present invention also aims to provide a two-wire transmitter capable of transmitting information from the receiving side 1 to the field at the same time as information signals from the field.
すなわち、現場よりのアナログ信号は受信側よりの供給
定電圧で駆動される伝送器でもって測定量に比例は直流
電流信号に変換して伝送し、受信側よシの現場への各種
の情報は受信側より現場に２本の伝送線を介して供給さ
れる伝送器駆動用電源としての定電圧のレベルを現場に
伝送される各情に応じて割り当でることにより現場では
伝送線に供給された定電圧レベルを検出して供給された
定電圧より受信側よりの各情報信号を取り出す。In other words, the analog signal from the field is converted into a DC current signal proportional to the measured quantity by a transmitter driven by a constant voltage supplied from the receiving side, and transmitted, and various information from the receiving side to the field is transmitted. By allocating the level of the constant voltage as the power source for transmitter drive, which is supplied from the receiving side to the field via two transmission lines, according to the various information transmitted to the field, the level of the constant voltage that is supplied to the transmission line at the field is The constant voltage level is detected and each information signal from the receiving side is extracted from the supplied constant voltage.
これによって現場よりの連続アナログ信号と受信側より
現場への各種指令信号が２本の伝送線でもって同時に伝
送できる。This allows continuous analog signals from the field and various command signals from the receiving side to the field to be transmitted simultaneously over two transmission lines.
すなわち現場よりの信号は受信側の定電圧の供給を受は
現場よりの伝送器の定電流特性回路によりその伝送線に
測定量に比例は直流定電流信号を受信側に２本の伝送線
を介して伝送することができ 又受信側よりの各種情報
信号は受信側の伝送器に供給する定電圧装置の電圧を変
化させ現場ではその供給電圧レベルを検出し制御するこ
とにより受信側より送られた電圧レベルより受信側の情
報を理解することができる。In other words, the signal from the field is supplied with a constant voltage on the receiving side, and the constant current characteristic circuit of the transmitter from the field sends a direct current constant current signal proportional to the measured amount to the transmission line, which is connected to two transmission lines on the receiving side. Various information signals from the receiving side can be transmitted from the receiving side by changing the voltage of a constant voltage device that supplies the transmitter on the receiving side, and detecting and controlling the supply voltage level at the site. The information on the receiving side can be understood from the voltage level.
つぎにこの考案の実施例について図面により説明する。Next, an embodiment of this invention will be described with reference to the drawings.
第１図はこの考案の構成を示す回路図である。FIG. 1 is a circuit diagram showing the configuration of this invention.
図において■１〜Ｖｎは定電圧装置（駆動電力源）で、
これらの電圧値（レベル）はそれぞれ異なっており、こ
の電圧レベルによってに送量の位置する現場では受信側
よりの情報判断を行う。In the figure, ■1 to Vn are constant voltage devices (driving power sources),
These voltage values (levels) are different, and information from the receiving side is determined based on these voltage levels at the site where the amount of data to be sent is located.
Ａは電流検出装置で、これｌこより現場よりの測定量に
比例したアナログ情報、すなわち直流電流信号を取り出
す。A is a current detection device from which analog information proportional to the measured amount from the field, that is, a DC current signal, is extracted.
ＳＷは定電圧装置■１〜Ｖｎを択一的に伝送線ｔに接続
する切り換えスイッチ、ｔは受信側と現場を結ぶ２本の
伝送線、Ｑは測定量をそれに比例した４〜２０ｍＡの直
流電流信号に変換する高利得のトランジスターで、伝送
器Ｔの主要部を構成するもので、コレクタならびにエミ
ッタは伝送線ｔに接続されている。SW is a voltage regulator switch that selectively connects 1 to Vn to the transmission line t, t is the two transmission lines connecting the receiving side and the site, and Q is a 4 to 20 mA DC proportional to the measured quantity. This is a high-gain transistor that converts into a current signal, and constitutes the main part of the transmitter T, and its collector and emitter are connected to the transmission line t.
このトランジスタＱの出力電流が伝送線ｔを通して受信
側の電流検出装置Ａに流れる。The output current of this transistor Q flows through the transmission line t to the current detection device A on the receiving side.
Ｂは前記トランジスタＱのベースｌこアナログ情報信号
を与えるポテンショメータでＥはその基準定電圧であり
、前記ベースは測定量に応じてポテンショメータＲ上を
移動する。B is a potentiometer that provides an analog information signal to the base of the transistor Q, E is its reference constant voltage, and the base moves on the potentiometer R in accordance with the measured quantity.
ＭＣ１−ＭＣｎは前記スイッチＳＷによって選択された
定電圧装置■１〜Ｖｎの各電圧レベル、すなわち伝送器
Ｔの供給電圧レベルを検出し、受信側よりの情報（指令
）を検出し取り出す電圧レベル検出装置（コンパレータ
）である。MC1 to MCn are voltage level detectors that detect each voltage level of voltage regulators 1 to Vn selected by the switch SW, that is, the supply voltage level of the transmitter T, and detect and extract information (commands) from the receiving side. It is a device (comparator).
これら前記トランジスタＱのコレクタに並列に接続され
、かつ、それらは受信側に位置する定電圧装置■１〜Ｖ
ｎに対応している。Constant voltage devices 1 to V connected in parallel to the collectors of these transistors Q and located on the receiving side
It corresponds to n.
なお図中鎖線から右が測定対象のある場所すなわち現場
で、左が受信側である。In the figure, the area to the right of the chain line is the location where the measurement target is located, that is, the site, and the area to the left is the receiving side.
またｒはトランジスタＱのエミッタ抵抗である。Further, r is the emitter resistance of the transistor Q.
上記構成において、図示の状態では伝送線ｔには定電圧
装置■１が供給され、トランジスタＱのベース電位に応
じた定電流ｌ、すなわち測定量に比例した直流電流が伝
送線ｔに流れ、受信側の電流検出装置Ａで検出される。In the above configuration, in the illustrated state, a constant voltage device 1 is supplied to the transmission line t, and a constant current l corresponding to the base potential of the transistor Q, that is, a direct current proportional to the measured quantity flows through the transmission line t, and the reception It is detected by the current detection device A on the side.
この場合、トランジスタＱのベース電位すなわち測定量
に応じてコレクタ電圧は変化しようとするが、このトラ
ンジスタＱには受信側より定電圧装置■１の電圧が供給
されているので、その作用により伝送線ｔならびに抵抗
ｒの抵抗値を無視すれば電圧ｖ１に保持され、この電圧
が電圧レベル検出装置ＭＣ１で検出され、受信側より定
電圧装置■１により電力供給がなされていることが現場
で感知される。In this case, the collector voltage tends to change depending on the base potential of the transistor Q, that is, the measured quantity, but since the voltage of the voltage regulator ■1 is supplied to the transistor Q from the receiving side, the transmission line If t and the resistance value of the resistor r are ignored, the voltage is held at v1, and this voltage is detected by the voltage level detection device MC1, and it is sensed at the site that power is being supplied from the receiving side by the constant voltage device 1. Ru.
すなわち伝送線ｔには、トランジスタＱで変換された測
定量に比例した電流が流れ、受信側に伝送され、受信側
よりの供給電圧は電圧検出装置ＭＣ１でもって検出され
る。That is, a current proportional to the measured quantity converted by the transistor Q flows through the transmission line t, and is transmitted to the receiving side, and the voltage supplied from the receiving side is detected by the voltage detection device MC1.
つぎにスイッチＳＷを定電圧装置■２に切り換えると、
伝送器ＴのトランジスタＱのコレクターベース間に電圧
ｖ２が供給されるが、トランジスタＱは高インピーダン
スを有するので、供給電圧の変化に関係なく定電圧装置
■１よりの電圧ｖ１の供給時と同様に測定量に比例した
直流電流に変換された電流が伝送線に流れると共にこの
時の供給電圧■２が電圧レベル検出装置ＭＣ２で検出さ
れ、定電圧装置■２でもって電力供給が□なされている
ことが感知される。Next, when switch SW is switched to constant voltage device ■2,
Voltage v2 is supplied between the collector and base of transistor Q of transmitter T, but since transistor Q has high impedance, regardless of changes in the supply voltage, voltage v1 is supplied from voltage regulator ■1 in the same way as when voltage v1 is supplied from voltage regulator ■1. A current converted to a direct current proportional to the measured quantity flows through the transmission line, and the supply voltage (2) at this time is detected by the voltage level detection device (MC2), and power is supplied by the constant voltage device (2). is sensed.
したがってこの電圧レベルｖ２が受信１細よりの停止指
令の情報信号であるとすると、電圧レベル検出装置ＭＣ
２の出力でもって例えばバルブの開閉操作を停止させる
ことができる。Therefore, if this voltage level v2 is the information signal of the stop command from the reception 1, then the voltage level detection device MC
With the second output, for example, the opening/closing operation of a valve can be stopped.
第２図はスイッチＳＷにより伝送線ｔに接続される定電
圧装置ｖ１〜Ｖｎの電圧■１〜Ｖｎと現場で検出される
と出力信号との関係を示す図で図ａは受信側のスイッチ
ＳＷによる定電圧レベルとトランジスタＱのコレクタ電
圧■Ｌの電圧変動との関係を示すもので、右図のε■は
トランジスタによる定電流変換による伝送線ｔの抵抗ｒ
Ｌ１抵抗ｒの電圧降下によるコレクタ電圧Ｖｃの変動を
意味する。Figure 2 is a diagram showing the relationship between the voltages 1 to Vn of the constant voltage devices v1 to Vn connected to the transmission line t by the switch SW and the output signal detected at the site, and Figure a is the switch SW on the receiving side. This shows the relationship between the constant voltage level and the voltage fluctuation of the collector voltage L of the transistor Q. ε■ in the right figure is the resistance r of the transmission line t due to constant current conversion by the transistor.
It means the fluctuation of the collector voltage Vc due to the voltage drop of the L1 resistor r.
この電圧ε■はε■＝電流変化ＪＩＸ（ｒｔ＋２ｒＬ） で現わされる。This voltage ε■ is ε■ = current change JIX (rt+2rL) It is expressed as
したがって電圧レベル検出装置ＭＣＩ−ＭＣｎは、この
電圧変化ε■によって右左されないよう設計しておく必
要がある。Therefore, the voltage level detection devices MCI-MCn must be designed so as not to be affected by this voltage change ε■.
図すに示すように受信側の定電圧装置ｖ１〜Ｖｎの切り
換えによる電圧レベルに応じて現場では、それに対応し
た電圧レベル検出装置に出力信号が生じることにより受
信側の情報が現場に伝送され、たことｌこなる。As shown in the figure, information on the receiving side is transmitted to the site by generating an output signal to the corresponding voltage level detection device at the site according to the voltage level by switching the voltage regulators v1 to Vn on the receiving side. This is what happened.
また受信側よりの各情報を同時に送ることもマドノック
３回路を構成することにより一度に多くの情報を同時に
伝送できる。Also, by configuring the Madnock 3 circuit, a large amount of information can be transmitted simultaneously from the receiving side.
定電流伝送も同様である。The same applies to constant current transmission.
以上の実施例では定電圧レベルでの切り換えで情報を受
信側より現場に伝送するようにしたが伝送時間（パルス
巾）によっても情報伝達は可能である。In the above embodiments, information is transmitted from the receiving side to the site by switching at a constant voltage level, but information can also be transmitted by changing the transmission time (pulse width).
また両者を組み合すことにより、より多くの情報伝達も
可能である。Furthermore, by combining the two, it is possible to transmit more information.
以上詳述したように、この考案は２本の伝送線に多くの
情報を受信側より現場に伝送することができ、かつ、現
場よりも測定量に比例した直流電流信号としての連続ア
ナログ信号を同時ｌこ伝送することができる。As explained in detail above, this invention allows a large amount of information to be transmitted from the receiving side to the field over two transmission lines, and it also transmits a continuous analog signal in the form of a DC current signal proportional to the measured quantity, rather than at the field. It is possible to transmit multiple signals at the same time.
また構成においても、受信側にはスイッチ０切換で電圧
値レベルの異なる駆動電力を伝送路に供給するとともに
、伝送器Ｏ）位置する現場には、単に複数の電圧検出装
置を設けるだけで、単に測定量信号のみならず種類の異
なる信号を送信することができ、又、伝送回路の増設を
せずとも単に切換電圧値の数およびそれに応じた電圧検
出器の数の増減だけで自由に信号の伝達種類数も調節す
ることができるので、この考案は実用に供した場合その
効果は極めて顕著である。In addition, in the configuration, driving power with different voltage levels is supplied to the transmission line by switching the switch 0 on the receiving side, and multiple voltage detection devices are simply installed at the site where the transmitter is located. It is possible to transmit not only measured quantity signals but also different types of signals, and signals can be transmitted freely by simply increasing or decreasing the number of switching voltage values and the number of voltage detectors accordingly, without adding a transmission circuit. Since the number of types of transmission can also be adjusted, the effect of this invention will be extremely significant when put into practical use.
第１図はこの考案の実施例を示す回路図、第２図は第１
図の動作説明用図である。
■１〜■ｎ；定電圧装置、ＳＷ：切換スイッチ、Ａ：電
流検出装置、ｔ＝伝送線、Ｔ：伝送器（変換器）、Ｑ：
伝送器Ｔの電流制御用トランジスタ、Ｒ：ポテンショメ
ータ、Ｅ：ポテンショメータの電源、ＭＣ１〜ＭＣｎ二
電圧検出装置。Figure 1 is a circuit diagram showing an embodiment of this invention, and Figure 2 is a circuit diagram showing an embodiment of this invention.
It is a diagram for explaining the operation of the figure. ■1 to ■n; Constant voltage device, SW: Changeover switch, A: Current detection device, t=transmission line, T: Transmitter (converter), Q:
Transmitter T current control transistor, R: potentiometer, E: potentiometer power supply, MC1 to MCn two voltage detection devices.
Claims (1)
の伝送線を介して受信側に伝送するとともにこの伝送線
を介して変換器に駆動電力を供給するようにしたものに
おいて、上記伝送線の受信側の電流検出装置に直列に、
切換スイッチを介して上記駆動電力源としての異なる電
圧値の複数の電源を切換接続するよう接続するとともに
、上記供給される電圧値に対応したそれぞれの異なる検
出電圧値レベルを有し、その値で出力信号を出す複数の
電圧検出装置を上記変換器側の伝送線に並列に設けてな
ることを特徴とする２線式伝送器。In a device in which the output of a converter that converts a measured quantity into a DC current signal is transmitted to the receiving side via a pair of transmission lines, and driving power is supplied to the converter via this transmission line, the above-mentioned transmission In series with the current sensing device on the receiving end of the line,
A plurality of power supplies having different voltage values as the driving power source are connected to each other via a changeover switch, and each has a different detection voltage value level corresponding to the supplied voltage value, and at that value. A two-wire transmitter characterized in that a plurality of voltage detection devices for outputting output signals are provided in parallel on a transmission line on the converter side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1975176406U JPS5821039Y2 (en) | 1975-12-27 | 1975-12-27 | 2 Senshikidensouki |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1975176406U JPS5821039Y2 (en) | 1975-12-27 | 1975-12-27 | 2 Senshikidensouki |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5290055U JPS5290055U (en) | 1977-07-05 |
| JPS5821039Y2 true JPS5821039Y2 (en) | 1983-05-02 |
Family
ID=28654714
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1975176406U Expired JPS5821039Y2 (en) | 1975-12-27 | 1975-12-27 | 2 Senshikidensouki |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5821039Y2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59201536A (en) * | 1983-04-30 | 1984-11-15 | Yamatake Honeywell Co Ltd | Method and apparatus of analog-digital communication |
| JPS59201539A (en) * | 1983-04-30 | 1984-11-15 | Yamatake Honeywell Co Ltd | Analog-digital communication method |
| DE10342625A1 (en) * | 2003-09-15 | 2005-04-14 | Robert Bosch Gmbh | sensor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4710237U (en) * | 1971-03-05 | 1972-10-06 | ||
| JPS505062A (en) * | 1972-04-20 | 1975-01-20 |
-
1975
- 1975-12-27 JP JP1975176406U patent/JPS5821039Y2/en not_active Expired
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4710237U (en) * | 1971-03-05 | 1972-10-06 | ||
| JPS505062A (en) * | 1972-04-20 | 1975-01-20 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5290055U (en) | 1977-07-05 |
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