JPH0467895B2 - - Google Patents
Info
- Publication number
- JPH0467895B2 JPH0467895B2 JP61267686A JP26768686A JPH0467895B2 JP H0467895 B2 JPH0467895 B2 JP H0467895B2 JP 61267686 A JP61267686 A JP 61267686A JP 26768686 A JP26768686 A JP 26768686A JP H0467895 B2 JPH0467895 B2 JP H0467895B2
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- differential pressure
- pressure transmitter
- water level
- air
- 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 - Lifetime
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 238000003780 insertion Methods 0.000 claims description 9
- 230000037431 insertion Effects 0.000 claims description 9
- 238000010926 purge Methods 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 6
- 238000001514 detection method Methods 0.000 description 9
- 238000005259 measurement Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000010865 sewage Substances 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
Landscapes
- Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
Description
〔産業上の利用分野〕
本発明は各種プロセスの液位測定に係り、特に
下水処理場の雨水ポンプ井の様な突発的な水位変
動に対して迅速に対応する必要がある高信頼性を
要求される液位測定回路に好適なオンライン校正
回路を用いた制御装置に関するものである。
〔従来技術〕
液位測定に関する最近の技術としては特開昭60
−98328号が公知である。
上記公知技術においては、圧力検知部の精度を
向上させる為に温度補償、静圧補償について工夫
されているが、差圧伝送器の自動校正や故障検出
については格別の考慮が為されていなかつた。
〔発明が解決しようとする問題点〕
上記従来技術は、差圧伝送器検出端の精度向上
の為の温度、静圧補償方法に関しては考慮されて
いるが、差圧伝送器の自動校正、及び、故障検出
方法に関しては、考慮されておらず、差圧伝送器
の故障及び、自動校正による、差圧信号の適正さ
の判断までは配慮されていない為、差圧伝送器を
用いた水位計の信頼性の向上が出来ないという問
題があつた。
本発明の目的は、差圧伝送器本体の故障検出及
び、自動校正を可能にし、エアーパージ式水位計
の信頼性の向上を計る事にある。
〔問題点を解決するための手段〕
上記の目的を解決するため創作した本発明の装
置は、液位を計測する個所に計装用圧力空気を吐
出する挿入管と、上記の挿入管に供給する計装用
圧力空気の流量を調節する流量調節弁を内蔵した
エアーパージセツトと、前記挿入管内の圧力の大
気圧に対する差圧を計測する機能を備えた差圧伝
送器とを設けたエアーパージ式水位計に適用され
(a)前記差圧伝送器の挿入管側圧力印加部に規定の
圧力を印加する圧力制御手段と、(b)上記の規定圧
力を印加した状態における差圧伝送器の出力信号
が適正値であるか否かを判定する自動的手段とを
設けたものである。
〔作用〕
上記の構成によれば、前記(a)項の圧力制御手段
によつて差圧伝送器に規定圧力を実際に印加し、
規定圧力を印加した状態で発生する圧力信号を用
いて前記(b)項の適否判定手段によつて校正を行う
ことが出来る。また、この校正操作と校正結果に
より故障検出も可能である。
〔実施例〕
第１図は本発明の自動校正制御装置の１実施例
を備えた水位計の説明図である。
挿入管１０を用いた検出端により水位測定のル
ープ構成は、空気発生源（記入せず）から供給さ
れた計装用空気AIRが定流量弁１１を経て、一定
流量の計装用空気がエアーパージセツト１に導入
され、電磁弁３（SV２）を介して挿入管１０に
送られる。差気伝送器９の片側は大気開放されて
おり大気圧（PA）が印加されている。他方、電
磁弁４（SV３）を経由した側はPAと背圧（ΔP）
との和を加算した圧力が印加される。差圧伝送器
９の出力信号は、ΔPに比例した信号が出力され
る。ΔPは、水深ｈと水の比重との積でありΔPか
ら水深が測定出来る。
本例の装置は、差圧伝送器９の挿入管側圧力印
加部９ａの規定圧力を印加する手段として源圧弁
７を設けてある。
そして、前記の圧力印加部９ａに規定圧力を加
えたときに差圧伝送器９が発する出力信号９ｂが
適正値であるか否かを判定する機能を備えたデイ
ジタル演算器８を設けてある。
電磁弁５（SV４）は減圧弁７と直列に接続し
てあり、この電磁弁５（SV４）を閉じると減圧
弁７は水位計の機能に関与しなくなる。
第１図乃至第３図は同一の実施例を示す系統図
であつて、その異なるところは５個の弁（SV１
〜SV５）の開閉状態である。
第１図は水位計として機能する「通常」状態で
あり、第２図はデイジタル演算器８の「ゼロ点調
整」を行う状態であり、第３図は差圧伝送器９に
フルスパンを与えて出力信号の適否を判定する
「スパン調整」状態である。
第１図乃至第３図における〓〓マークは開弁状
態の示し、〓〓マークは閉弁状態を示している。
第１図乃至第５図における弁の開閉状態を表に
して示すと次表の如くである。×印は閉弁を表わ
し、○印は開弁を表わしている。
[Industrial Field of Application] The present invention relates to liquid level measurement in various processes, and particularly to systems that require high reliability, such as in rainwater pump wells in sewage treatment plants, where it is necessary to quickly respond to sudden changes in water level. The present invention relates to a control device using an online calibration circuit suitable for a liquid level measurement circuit used in a liquid level measurement circuit. [Prior art] The latest technology related to liquid level measurement is JP-A-60
-98328 is publicly known. In the above-mentioned known technology, temperature compensation and static pressure compensation have been devised to improve the accuracy of the pressure detection section, but no special consideration has been given to automatic calibration or failure detection of the differential pressure transmitter. . [Problems to be Solved by the Invention] The above-mentioned prior art takes into consideration the temperature and static pressure compensation method for improving the accuracy of the detection end of the differential pressure transmitter, but it does not solve the problem of automatic calibration of the differential pressure transmitter and , the failure detection method is not considered, and the failure of the differential pressure transmitter and the judgment of the appropriateness of the differential pressure signal through automatic calibration are not considered. There was a problem that the reliability of the system could not be improved. An object of the present invention is to enable failure detection and automatic calibration of the main body of a differential pressure transmitter, and to improve the reliability of an air purge type water level gauge. [Means for Solving the Problems] The device of the present invention created to solve the above object includes an insertion tube for discharging instrument pressure air to the location where the liquid level is to be measured, and a device for supplying pressure air to the insertion tube. An air purge type water level equipped with an air purge set that has a built-in flow control valve that adjusts the flow rate of pressurized air for instrumentation, and a differential pressure transmitter that has a function to measure the differential pressure between the pressure inside the insertion tube and the atmospheric pressure. applied to the meter
(a) Pressure control means for applying a specified pressure to the insertion tube side pressure application part of the differential pressure transmitter; (b) An output signal of the differential pressure transmitter with the above specified pressure applied is an appropriate value. automatic means for determining whether or not there is one. [Operation] According to the above configuration, the specified pressure is actually applied to the differential pressure transmitter by the pressure control means of the above item (a),
Calibration can be performed by the suitability determination means described in (b) above using a pressure signal generated when a specified pressure is applied. Furthermore, failure detection is also possible based on this calibration operation and calibration results. [Embodiment] FIG. 1 is an explanatory diagram of a water level gauge equipped with an embodiment of the automatic calibration control device of the present invention. The loop configuration for water level measurement using the detection end using the insertion tube 10 is that instrumentation air AIR supplied from an air source (not written) passes through the constant flow valve 11, and a constant flow rate of instrumentation air enters the air purge set. 1 and sent to the insertion tube 10 via the solenoid valve 3 (SV2). One side of the differential air transmitter 9 is open to the atmosphere, and atmospheric pressure (P A ) is applied thereto. On the other hand, the side that passes through solenoid valve 4 (SV3) is PA and back pressure (ΔP).
The pressure obtained by adding the sum of is applied. The differential pressure transmitter 9 outputs a signal proportional to ΔP. ΔP is the product of the water depth h and the specific gravity of water, and the water depth can be measured from ΔP. The device of this example is provided with a source pressure valve 7 as a means for applying a specified pressure to the insertion tube side pressure applying section 9a of the differential pressure transmitter 9. A digital calculator 8 is provided which has a function of determining whether the output signal 9b generated by the differential pressure transmitter 9 when a specified pressure is applied to the pressure applying section 9a is a proper value. The solenoid valve 5 (SV4) is connected in series with the pressure reducing valve 7, and when the solenoid valve 5 (SV4) is closed, the pressure reducing valve 7 no longer participates in the function of the water level gauge. Figures 1 to 3 are system diagrams showing the same embodiment, and the difference is that five valves (SV1
-SV5) are open and closed. Fig. 1 shows the "normal" state in which it functions as a water level gauge, Fig. 2 shows the state in which the digital calculator 8 is "zero adjusted", and Fig. 3 shows the state in which the differential pressure transmitter 9 is given full span. This is the "span adjustment" state in which the suitability of the output signal is determined. In FIGS. 1 to 3, the 〓〓 mark indicates the valve open state, and the 〓〓 mark indicates the valve closed state. The following table shows the opening and closing states of the valves in FIGS. 1 to 5. An x mark indicates a closed valve, and an ○ mark indicates an open valve.
本発明によれば、差圧伝送器に規定圧力を実際
に印加して差圧伝送器の規定圧力に従つた圧力信
号により差圧伝送器を校正する事が出来るので、
差圧伝送器本体の故障検出及び、自動校正が可能
になり、検出端の高信頼性を確立できる為、下水
処理場の雨水ポンプ井等における、突発的な水位
変動に対して確実に対応することが可能となる。
According to the present invention, the differential pressure transmitter can be calibrated by actually applying the specified pressure to the differential pressure transmitter and using a pressure signal according to the specified pressure of the differential pressure transmitter.
It enables failure detection and automatic calibration of the differential pressure transmitter body, ensuring high reliability of the detection end, and can reliably respond to sudden water level fluctuations in rainwater pump wells of sewage treatment plants, etc. becomes possible.
第１図乃至第３図は本発明の一実施例における
系統図であつて、第１図は水位計として通常の稼
働状態を示し、第２図はスパン調整状態を示し、
第３図は零点調整状態を示す。第４図はデイジタ
ル演算器の内部構成の説明図である。
１……エアーパージセツト、２〜６……電磁
弁、７……減圧弁、８……デイジタル演算器、９
……差圧伝送器、１０……挿入管、１１……定流
量弁、１２……外部SW、１３……計算機、１４
……零調整出力ブロツク、１５……フルスパン調
整出力ブロツク、１６……通常出力ブロツク。
1 to 3 are system diagrams in one embodiment of the present invention, in which FIG. 1 shows the normal operating state as a water level gauge, and FIG. 2 shows the span adjustment state,
FIG. 3 shows the zero point adjustment state. FIG. 4 is an explanatory diagram of the internal configuration of the digital arithmetic unit. 1... Air purge set, 2-6... Solenoid valve, 7... Pressure reducing valve, 8... Digital calculator, 9
... Differential pressure transmitter, 10 ... Insertion tube, 11 ... Constant flow valve, 12 ... External SW, 13 ... Computer, 14
... Zero adjustment output block, 15 ... Full span adjustment output block, 16 ... Normal output block.
Claims (1)
する挿入管と、上記の挿入管に供給する計装用圧
力空気の流量を調節する流量調節弁を内蔵したエ
アーパージセツトと、前記挿入管内の圧力の大気
圧に対する差圧を計測する機能を備えた差圧伝送
器とを設けたエアーパージ式水位計において、(a)
前記差圧伝送器の挿入管側圧力印加部に規定の圧
力を印加する圧力制御手段と、(b)上記の規定圧力
を印加した状態における差圧伝送器の出力信号が
適正値であるか否かを判定する自動的手段とを設
けたことを特徴とする、エアーパージ式水位計の
自動校正制御装置。1. An insertion tube that discharges instrumentation pressure air to the location where the liquid level is to be measured; In an air purge type water level gauge equipped with a differential pressure transmitter equipped with a function to measure the difference in pressure with respect to atmospheric pressure, (a)
(b) whether or not the output signal of the differential pressure transmitter in a state where the above specified pressure is applied is an appropriate value; An automatic calibration control device for an air purge type water level gauge, characterized in that it is provided with an automatic means for determining whether
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61267686A JPS63121704A (en) | 1986-11-12 | 1986-11-12 | Automatic calibration control device for water level meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61267686A JPS63121704A (en) | 1986-11-12 | 1986-11-12 | Automatic calibration control device for water level meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63121704A JPS63121704A (en) | 1988-05-25 |
| JPH0467895B2 true JPH0467895B2 (en) | 1992-10-29 |
Family
ID=17448122
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61267686A Granted JPS63121704A (en) | 1986-11-12 | 1986-11-12 | Automatic calibration control device for water level meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63121704A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4913379B2 (en) * | 2005-09-12 | 2012-04-11 | 株式会社ノーケン | Barometric liquid level detector |
| AU2008217000B2 (en) | 2007-09-21 | 2012-02-09 | Multitrode Pty Ltd | A pumping installation controller |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55109827U (en) * | 1979-01-30 | 1980-08-01 |
-
1986
- 1986-11-12 JP JP61267686A patent/JPS63121704A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63121704A (en) | 1988-05-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |