CN103257157A - Combustible gas detector and calibration method thereof - Google Patents
Combustible gas detector and calibration method thereof Download PDFInfo
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- CN103257157A CN103257157A CN2013101508736A CN201310150873A CN103257157A CN 103257157 A CN103257157 A CN 103257157A CN 2013101508736 A CN2013101508736 A CN 2013101508736A CN 201310150873 A CN201310150873 A CN 201310150873A CN 103257157 A CN103257157 A CN 103257157A
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Abstract
The invention discloses a combustible gas detector. The combustible gas detector is composed of a power management unit, a main control chip unit, a sensor and an interface circuit unit, an output alarm unit, a V/I conversion circuit unit and a communication circuit unit, wherein the power management unit is connected with the other units and can provide power for the other units; the main control chip unit is connected with the sensor and the interface circuit unit, the communication circuit unit, the output alarm unit and the V/I conversion circuit unit, controls the communication circuit unit to be communicated with an upper computer, carries out digitization on data processed through the sensor and the interface circuit unit, and configures an interface circuit connected with the sensor and the interface circuit unit; and the communication circuit unit, the output alarm unit and the V/I conversion circuit unit are enabled or prohibited through the main control chip unit. The combustible gas detector provided by the invention is connected with an upper computer PC with display and interface operational software through a communication module, the parameter calibration such as internal compensation and gain of the combustible gas detector is realized in an on-line manner through the operation on the software, the detecting precision is less influenced by temperature, and large-scale manufacturing and calibration are conveniently realized.
Description
Technical field
The present invention relates to the gas detector field, specifically refer to a kind of combustible gas probe and scaling method thereof.
Background technology
From domestic and international development, the combustible gas probe product just develops towards low in energy consumption, life-span length, good stability, technical merit advanced person, digitizing bus system, the high direction of multi-functional, integrated, intelligent degree.It is new and old and deposit that the fast development of gas detector makes that the detection of gas product shows as: the multiple-way system combustible gas probe of being made up of sensing element, amplifying circuit, probe body; Export 4 ~ 20mA standard signal, have the multiple-way system inflammable gas transmitter that (or not having) on-the-spot concentration shows; Bus-type switching value detector and analogue detector; Finish signals collecting, data processing, fault arbitration functions by the scene, carry out the bus type gas detector of digital quantity transport communication then with controller.When selecting the detection of gas product, mainly be to select wherein a kind of detector according to practical application request, different demands is corresponding different product often.When user's request changes, need carry out the type selecting of detector again, brought trouble for production and application.And along with improving constantly that the gas detector art requires, the said goods can not satisfy the developing direction of combustible gas probe.
Main product is not in the market supported detector is demarcated, can only mend temperature drift, error by built-in adjustable resistance and taste, this method does not have consistance in whole temperature range, and the convenience deficiency of demarcating, adjusting also is not suitable for production debugging in batches.
Summary of the invention
In order to overcome the shortcoming that existing combustible gas probe (203) is not suitable for multiple user demand and demarcation, adjustment inconvenience, make combustible gas probe (203) applicable to various applied environments and availablely demarcate easily, debug, the present invention has designed a kind of combustible gas probe (203) and scaling method thereof.
For achieving the above object, technical scheme of the present invention provides a kind of combustible gas probe (203) on the one hand, comprise Power Management Unit (101), main control chip unit (102), sensor and interface circuit unit (103), output alarm unit (104), V/I conversion circuit unit (105), telecommunication circuit unit (106).
Wherein said Power Management Unit (101) links to each other with each unit in the circuit, for each unit provides power supply;
Wherein said main control chip unit (102) comprising:
Main control chip is connected with each unit, is used for control telecommunication circuit unit, communicates with host computer, and the data that inner processing of circuit is crossed are carried out digitizing, and interface circuit is configured;
Reset circuit is connected with described main control chip, for generation of reset signal;
Clock circuit is connected with described main control chip, for generation of clock signal;
The background debugging unit is connected with described main control chip, is used for that described main control chip is carried out program and downloads, debugs.
Wherein said sensor and interface circuit unit (103) comprising:
Combustible gas sensor has and detects and compensate two variable resistor outputs, detects and compensate two changes in resistance, and compensation Yin Wendu, humidity change the sensor output drift that brings;
Wheatstone bridge circuits, be made up of built-in detection, the compensating resistance with the resistance half-bridge combustible gas sensor coupling and combustible gas sensor output of combustible gas probe (203), the built-in half-bridge of combustible gas probe has the convenient circuit parameter of determining built-in half-bridge when trial production, debugging of an adjustable resistance simultaneously;
The sensor interface chip, MLX90320 sensor interface chip can amplify the differential voltage signal of wheatstone bridge circuits output the trip temperature compensation of going forward side by side, and wherein enlargement factor and temperature compensation parameter can be demarcated.
Wherein said output alarm unit (104):
Output alarm unit (104) comprises the output of two-way high level and the output of one tunnel low level, and have overcurrent and comprise, can satisfy and use the different field that the needs high level is reported to the police or low level is reported to the police, can enable or forbid by described main control chip unit (102).
Described V/I conversion circuit unit (105):
The V/I change-over circuit is converted to 4 ~ 20mA current signal with the voltage signal of sensor interface chip output, can satisfy the demand to become the application of sending mode to export by electric current, can enable or forbids by described main control chip unit (102).
Described telecommunication circuit unit (106) comprising:
The CAN communication module, can be used as the CAN network node applies in the combustible gas detecting application based on the CAN network of the heavy vehicle of pluralities of fuel, clean energy resource, locomotive, boats and ships, and support online calibrating function, can be used as demarcation passage and host computer PC and carry out exchanges data, described main control chip unit (102) is carried out data scaling, can enable or forbid by described main control chip unit (102);
The RS-485 communication module can be used as industrial circle based on the combustible gas detecting field of 485 networks, can enable or forbids by described main control chip unit (102).
In the research to various combustible gas sensor, find, when sensor had just begun to switch on, its performance was also unstable, and its calibration result that carries out is not had reference significance, owing to the reasons such as the linearity of sensor, unavoidable calibrated error can appear in timing signal simultaneously.In order to improve these problems, technical scheme of the present invention provides the scaling method of a kind of combustible gas probe (203), combustible gas probe (203) is connected with host computer (201) PC that is mounted with demonstration and operation interface software by communication module (202), by the operation to demonstration and operation interface software, realization is to the demarcation of combustible gas probe (203) internal data, and concrete demarcation flow process may further comprise the steps:
301, the demonstration and the operation interface that are loaded in the host computer (201) are opened in beginning;
302, be connected with slave computer, be connected with combustible gas probe (203) by communication module (202), and read sensor interface chip configuration information in the combustible gas probe;
303, preheating to the wheatstone bridge circuits energising, is carried out preheating to combustible gas sensor;
304, system initialization is set, and the combustible gas probe of demarcating first (203) is carried out system initialization set.
305, carry out Zero calibration, after the combustible gas sensor preheating is finished, to the logical 0%LEL inflammable gas of combustible gas sensor, host computer sends current concentration to combustible gas probe (203) simultaneously, the coarse adjustment parameter of sensor and interface circuit unit (103) inner sensor interface chip is adjusted according to the signal of current concentration and combustible gas sensor output in the main control chip unit (102) of combustible gas probe (203);
306, but calibration point 1 is demarcated, under the situation that Zero calibration is finished, combustible gas probe (203) is proceeded to demarcate, feed the A%LEL inflammable gas to combustible gas sensor, host computer sends current concentration to combustible gas probe (203), and the fine tuning parameter of sensor and interface circuit unit (103) inner sensor interface chip is adjusted in the main control chip unit (102) of combustible gas probe (203) according to the signal of current concentration and combustible gas sensor output;
307, demarcate checking, the inflammable gas that leads to 0%LEL, B%LEL, A%LEL respectively to combustible gas sensor, host computer sends corresponding concentration to combustible gas probe (203) simultaneously, the main control chip unit (102) of combustible gas probe (203) compares according to the signal of current concentration and combustible gas sensor output, if error (should be 3%LEL by standard) in allowed band, then verify under the current concentration and pass through;
308, demarcate successfully, if accuracy requirement is all satisfied in the demarcation of 0%LEL, B%LEL, A%LEL inflammable gas checking, then demarcate successfully;
309, demarcate failure, if among 0%LEL, B%LEL, the A%LEL under a certain concentration demarcation checking of inflammable gas exist and exceed the accuracy requirement scope, then finish to demarcate, enter next and demarcate flow process;
310, finish, demarcate and finish, write and demarcate the date, combustible gas probe (203) outage is prepared to carry out the next one (inferior) combustible gas probe (203) and is demarcated.
The invention has the beneficial effects as follows:
By designing a platform, disparate modules can be made up, realize product diversification; Can be according to customer requirements, can not influence other Module Design in the time of the increase and decrease module, extendability is strong; The mode signal output variation, bigger meets the need of market; The detection accuracy temperature influence is less; The present invention simultaneously supports parameters such as online internal compensation to combustible gas probe (203), gain to demarcate, and is convenient to large-scale production and calibration operation.
Description of drawings
Fig. 1 is combustible gas probe internal circuit configuration block diagram of the present invention.
The 101-Power Management Unit, 102-main control chip unit, 103-sensor and interface circuit unit, 104-output alarm unit, 105-V/I conversion circuit unit, 106-telecommunication circuit unit.
Fig. 2 is the demarcation block diagram of combustible gas probe of the present invention.
The 201-host computer, 202-communication module, 203-combustible gas probe.
Fig. 3 is the demarcation process flow diagram of combustible gas probe of the present invention.
301-begins, and 302-is connected with slave computer, the 303-preheating, and the 304-system initialization is set, and 305-carries out Zero calibration, but the 306-calibration point is demarcated 1,307-demarcation checking, and 308-demarcates successfully, and 309-demarcates failure, and 310-finishes.
Embodiment
Below in conjunction with accompanying drawing, be that example describes in further detail the specific embodiment of the present invention with combustible gas sensor NAP-55A.
Outside 24V power supply is as the supply voltage input Power Management Unit 101 of total system, Power Management Unit 101 is given 5V electric system circuit supply with the 24V voltage transitions for 5V voltage by the voltage stabilizing chip, and 5V voltage is exported 2.5V again and given 2.5V electric system circuit supply after chip AMS1117-2.5 step-down.Among the present invention, what need the 5V power supply is main control chip unit 102, output alarm unit 104, and telecommunication circuit unit 106,
Sensor and interface circuit unit 103, telecommunication circuit unit 106; What need the 2.5V power supply is sensor and interface circuit unit 103; Output alarm unit 104, V/I conversion circuit unit 105 uses the 24V power voltage supply.Combustible gas probe links to each other with the host computer that is mounted with demonstration and operation interface software by communication module.
Sensor NAP-55A has high sensitivity to all inflammable gass, and its output voltage and gas concentration are the better linearity relation, and measurement range is 0 ~ 50%LEL(lower explosive limit).Inner formed by the catalytic combustion element of a pair of coupling: one be detecting element (
), another be compensating element, (
).Sensor and combustible gas probe 203 built-in build-out resistor half-bridges are formed wheatstone bridge circuits,, the output voltage the when resistance of build-out resistor half-bridge is used for regulating zero point makes and departs from scope zero point in 0 mV ± 35mV.
Before using, need to form the MAP relation table that is detected gas concentration and sensor and interface circuit unit 103 output voltages, for main control chip unit 102 can be gathered output voltage, in the calibration process to sensor interface chip MLX90320, corresponding output voltage was made as 0.5V when concentration was 0%LEL, corresponding output voltage was made as 4.5V when concentration was 50%LEL, and 0 ~ 0.5V and 4.5 ~ 5V are used for diagnostic sensor open circuit or short trouble.After adjusting enlargement factor and side-play amount under two kinds of different temperatures, in the EEPROM of sensor interface chip MLX90320, write temperature compensation parameter, can realize the first compensation phase that temperature is floated.Carry out the second order compensation three kinds of next can floating temperature of different temperatures.Output voltage after the process temperature compensation has the consistance of better linearity degree and each temperature range, can satisfy the acquisition precision requirement.
The invention is not restricted to the embodiment that embodiment is set forth.Any design consistent with the present invention or that inspired by the present invention all falls into protection scope of the present invention.
Claims (4)
1. a combustible gas probe is characterized in that, it is by Power Management Unit, the main control chip unit, and sensor and interface circuit unit, the output alarm unit, V/I conversion circuit unit and telecommunication circuit unit are formed, wherein:
Main control chip unit: be connected with sensor and interface circuit unit, telecommunication circuit unit, output alarm unit and V/I conversion circuit unit, control telecommunication circuit unit, communicate with host computer, and the data that sensor and interface circuit cell processing are crossed are carried out digitizing, be configured being attached thereto the interface circuit that connects;
Power Management Unit: link to each other with other each unit, for each unit provides power supply;
Sensor and interface circuit unit: comprise combustible gas sensor, wheatstone bridge circuits and sensor interface chip are gathered the combustable gas concentration signal;
Output alarm unit: comprise the output of two-way high level and the output of one tunnel low level, and have overcurrent protection;
V/I conversion circuit unit: the voltage signal of sensor interface chip output is converted to 4 ~ 20mA current signal;
Telecommunication circuit unit: comprise CAN communication module and RS-485 communication module, according to concrete application configuration;
Described telecommunication circuit unit, output alarm unit, V/I conversion circuit unit can enable or forbid by described main control chip unit.
2. a kind of combustible gas probe as claimed in claim 1, it is characterized in that, the build-out resistor half-bridge that combustible gas probe is built-in, form wheatstone bridge circuits with detection, the compensating resistance of combustible gas sensor output, the sensor interface chip amplifies the trip temperature compensation of going forward side by side with the differential voltage signal of this circuit output, can demarcate enlargement factor and temperature compensation parameter.
3. a kind of combustible gas probe as claimed in claim 1 is characterized in that, on-line proving is supported in described telecommunication circuit unit.
4. method that combustible gas probe as claimed in claim 1 is demarcated, it is characterized in that, combustible gas probe is connected with the host computer PC that is mounted with demonstration and operation interface software by communication module, by the operation to demonstration and operation interface software, realization is to the demarcation of combustible gas probe internal data, and concrete demarcation flow process may further comprise the steps:
A. begin, open the demonstration and the operation interface that are loaded in the host computer PC;
B.. combustible gas probe is connected with host computer PC by communication module, and read sensor interface chip configuration information;
C. preheating to the wheatstone bridge circuits energising, is carried out preheating to combustible gas sensor;
D. system initialization carries out initializing set to the combustible gas probe of demarcating first;
E. carry out Zero calibration, after the combustible gas sensor preheating is finished, inflammable gas to the logical concentration 0%LEL of combustible gas sensor, host computer sends current concentration to combustible gas probe simultaneously, the coarse adjustment parameter of sensor and interface circuit inner sensor interface chip is adjusted according to the signal of current concentration and combustible gas sensor output in the main control chip unit of combustible gas probe;
F. but calibration point demarcates 1, under the situation that Zero calibration is finished, combustible gas probe is proceeded to demarcate, inflammable gas to the logical concentration A%LEL of combustible gas sensor, host computer sends current concentration to combustible gas probe, and the fine tuning parameter of sensor and interface circuit unit inner sensor interface chip is adjusted in the main control chip unit of combustible gas probe according to the signal of current concentration and combustible gas sensor output;
I. demarcate checking, the inflammable gas that leads to 0%LEL, B%LEL, A%LEL respectively to combustible gas sensor, simultaneously, host computer sends corresponding concentration to combustible gas probe, the main control chip unit of combustible gas probe compares according to the signal of current concentration and combustible gas sensor output, if error in allowed band, is then verified under the current concentration and is passed through;
J. demarcate successfully, if accuracy requirement is all satisfied in the demarcation of 0%LEL, B%LEL, A%LEL inflammable gas checking, then demarcate successfully;
K. demarcate failure, if among 0%LEL, B%LEL, the A%LEL under a certain concentration demarcation checking of inflammable gas exceed the accuracy requirement scope, then finish to demarcate, enter next and demarcate flow process;
L. demarcate and finish, the combustible gas probe outage prepares to carry out the next one or combustible gas probe is next time demarcated.
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104849405A (en) * | 2015-04-29 | 2015-08-19 | 无锡时和安全设备有限公司 | Intelligent gas detector adjusting system |
| CN104916083A (en) * | 2015-05-20 | 2015-09-16 | 安庆师范学院 | Internet of things based intelligent combustible gas inspection detector and calibration method thereof |
| CN105092791A (en) * | 2015-08-12 | 2015-11-25 | 福建美营自动化科技有限公司 | Combustible and explosible gas detection device |
| CN105806898A (en) * | 2016-03-10 | 2016-07-27 | 电子科技大学 | Gas concentration calibration method for gas sensor |
| WO2016206383A1 (en) * | 2015-06-26 | 2016-12-29 | 中航泰德(深圳)海洋工程有限公司 | Gas detector and alarming method therefor |
| CN106324047A (en) * | 2015-07-03 | 2017-01-11 | 上海戴维蓝普传感技术有限公司 | Catalytic combustion sensor work life assessment device and method |
| CN110455869A (en) * | 2018-05-07 | 2019-11-15 | 中国石油化工股份有限公司 | The gas sensing monitoring probe and its application of included sampling resistor |
| CN110646466A (en) * | 2019-08-30 | 2020-01-03 | 浙江大华技术股份有限公司 | Calibration method, system and equipment of semiconductor type gas sensor |
| CN111595910A (en) * | 2020-04-16 | 2020-08-28 | 北京航天试验技术研究所 | Concentration calculation method |
| CN112557606A (en) * | 2021-02-28 | 2021-03-26 | 中国工程物理研究院核物理与化学研究所 | Auxiliary device special for measuring performance parameters of gas detector |
| CN113358284A (en) * | 2021-08-11 | 2021-09-07 | 成都千嘉科技有限公司 | Gas leakage detection method and system based on MEMS chip detector |
| CN113866362A (en) * | 2021-09-28 | 2021-12-31 | 明石创新(烟台)微纳传感技术研究院有限公司 | Intelligent efficient accurate oxygen measuring instrument calibration and compensation method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101358947A (en) * | 2008-09-22 | 2009-02-04 | 河南省日立信电子有限公司 | Intelligent SF6 gas sensor |
| CN201331531Y (en) * | 2009-01-19 | 2009-10-21 | 重庆梅安森科技发展有限责任公司 | High precision carbon monoxide sensor device |
| CN201885990U (en) * | 2010-12-07 | 2011-06-29 | 上海翼捷工业安防技术有限公司 | Intelligent gas sensor |
| CN201885989U (en) * | 2010-12-06 | 2011-06-29 | 上海翼捷工业安防技术有限公司 | Combustible gas detector |
| CN102944648A (en) * | 2012-11-15 | 2013-02-27 | 中国科学院自动化研究所 | Modular intelligent gas detecting device |
-
2013
- 2013-04-27 CN CN2013101508736A patent/CN103257157A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101358947A (en) * | 2008-09-22 | 2009-02-04 | 河南省日立信电子有限公司 | Intelligent SF6 gas sensor |
| CN201331531Y (en) * | 2009-01-19 | 2009-10-21 | 重庆梅安森科技发展有限责任公司 | High precision carbon monoxide sensor device |
| CN201885989U (en) * | 2010-12-06 | 2011-06-29 | 上海翼捷工业安防技术有限公司 | Combustible gas detector |
| CN201885990U (en) * | 2010-12-07 | 2011-06-29 | 上海翼捷工业安防技术有限公司 | Intelligent gas sensor |
| CN102944648A (en) * | 2012-11-15 | 2013-02-27 | 中国科学院自动化研究所 | Modular intelligent gas detecting device |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104849405A (en) * | 2015-04-29 | 2015-08-19 | 无锡时和安全设备有限公司 | Intelligent gas detector adjusting system |
| CN104916083A (en) * | 2015-05-20 | 2015-09-16 | 安庆师范学院 | Internet of things based intelligent combustible gas inspection detector and calibration method thereof |
| WO2016206383A1 (en) * | 2015-06-26 | 2016-12-29 | 中航泰德(深圳)海洋工程有限公司 | Gas detector and alarming method therefor |
| CN106324047A (en) * | 2015-07-03 | 2017-01-11 | 上海戴维蓝普传感技术有限公司 | Catalytic combustion sensor work life assessment device and method |
| CN105092791A (en) * | 2015-08-12 | 2015-11-25 | 福建美营自动化科技有限公司 | Combustible and explosible gas detection device |
| CN105806898B (en) * | 2016-03-10 | 2018-06-29 | 电子科技大学 | A kind of gas concentration scaling method for gas sensor |
| CN105806898A (en) * | 2016-03-10 | 2016-07-27 | 电子科技大学 | Gas concentration calibration method for gas sensor |
| CN110455869A (en) * | 2018-05-07 | 2019-11-15 | 中国石油化工股份有限公司 | The gas sensing monitoring probe and its application of included sampling resistor |
| CN110646466A (en) * | 2019-08-30 | 2020-01-03 | 浙江大华技术股份有限公司 | Calibration method, system and equipment of semiconductor type gas sensor |
| CN110646466B (en) * | 2019-08-30 | 2022-04-08 | 浙江大华技术股份有限公司 | Calibration method, system and equipment of semiconductor type gas sensor |
| CN111595910A (en) * | 2020-04-16 | 2020-08-28 | 北京航天试验技术研究所 | Concentration calculation method |
| CN112557606A (en) * | 2021-02-28 | 2021-03-26 | 中国工程物理研究院核物理与化学研究所 | Auxiliary device special for measuring performance parameters of gas detector |
| CN112557606B (en) * | 2021-02-28 | 2021-06-04 | 中国工程物理研究院核物理与化学研究所 | Auxiliary device special for measuring performance parameters of gas detector |
| CN113358284A (en) * | 2021-08-11 | 2021-09-07 | 成都千嘉科技有限公司 | Gas leakage detection method and system based on MEMS chip detector |
| CN113866362A (en) * | 2021-09-28 | 2021-12-31 | 明石创新(烟台)微纳传感技术研究院有限公司 | Intelligent efficient accurate oxygen measuring instrument calibration and compensation method |
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Application publication date: 20130821 |