CN204228303U - Intelligent digital pressure unit - Google Patents
Intelligent digital pressure unit Download PDFInfo
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- CN204228303U CN204228303U CN201420429645.2U CN201420429645U CN204228303U CN 204228303 U CN204228303 U CN 204228303U CN 201420429645 U CN201420429645 U CN 201420429645U CN 204228303 U CN204228303 U CN 204228303U
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Abstract
The utility model relates to pressure sensing arts, specifically provide a kind of intelligent digital pressure unit, comprise pressure transducer, microprocessor CPU, LCD MODULE, pwm signal processing module, communication output module, XTR115 chip, button design module, the output terminal of XTR115 chip is connected with the input end of pressure transducer, the input end of XTR115 chip is connected with the output terminal of pwm signal processing module, the output terminal of microprocessor CPU and LCD MODULE, pwm signal processing module is connected with the input end of communication output module, the output terminal of microprocessor CPU and pwm signal processing module, communication output module is connected with the input end of LCD MODULE.The utility model both can accomplish on-the-spot display, again can electric current long-distance transmissions, all right direct RS485 communication interface PLC, industrial computer etc.
Description
Technical field
The utility model relates to pressure sensing arts, is specifically related to a kind of intelligent digital pressure unit.
Background technology
The design and development of intelligent digital pressure unit, there are a lot of type and style, but existing intelligent digital pressure unit, many with HART agreement in the market, and major part be all import brand product, band RS485 communication just quite few.HART agreement, be in one's early years mainly used in pressure aspect thus in same DCS control system, can only coexist multiple kinds use simultaneously; Very high to the requirement of technician like this, simultaneously workload also increase.So according to the demand in market, the intelligent pressure transmitter of exploitation band RS485 communication, just necessitate.The very corn of a subject is low-power consumption, should meets band RS485 communication, again two-wire system output current DC4 ~ 20mA, also wants on-the-spot direct digital display; When namely ensureing that output of products electric current is no more than minimum 4mA, can normally work.
Utility model content
For above-mentioned technical matters, the utility model provides a kind of intelligent digital pressure unit, can accomplish on-the-spot display, again can electric current long-distance transmissions, can also directly RS485 communication interface PLC, industrial computer etc.
The utility model provides a kind of intelligent digital pressure unit, comprise pressure transducer, microprocessor, LCD MODULE, pwm signal processing module, communication output module, XTR115 chip, button design module, the output terminal of XTR115 chip is connected with the input end of pressure transducer, the input end of XTR115 chip is connected with the output terminal of pwm signal processing module, the output terminal of microprocessor and LCD MODULE, pwm signal processing module is connected with the input end of communication output module, the output terminal of microprocessor and pwm signal processing module, communication output module is connected with the input end of LCD MODULE.
Described microprocessor is MSP430 single-chip microcomputer.
1 pin of described XTR115 chip is connected with operational amplifier U2, pressure transducer comprises the Hui Sitong bridge circuit be made up of 4 adjustable resistances, described Hui Sitong bridge circuit input end is connected with the feedback resistance Rs two ends of operational amplifier U2, and described Hui Sitong bridge circuit output terminal is connected with the pin P2.1 of microprocessor through operational amplifier U3.
Described pwm signal processing module comprise by resistance R10 and the pi type filter that forms of electric capacity C4, C5 and operational amplifier U4, the pin P1.3 of microprocessor is connected with the input end of pi type filter with operational amplifier U4 through resistance R9, and the output terminal of operational amplifier U4 is connected with 2 pin of XTR115 chip through resistance R15.
8 pin of described XTR115 chip are connected with three terminal regulator U5.The P3.0-3.2 pin of microprocessor respectively with three button control linkages.The P3.4-3.6 pin of microprocessor is connected with communication output integration block, and communication output integration block adopts SP485 chip, adopts RS485 communication modes, Modbus-RTU agreement.
5,6,7 pin of described XTR115 chip are connected with the emitter of triode Q1, base stage and collector respectively, 8 pin of XTR115 chip are connected with 24V positive source through diode D1,4 pin of XTR115 chip are connected with 24V power cathode, are connected with electric capacity C1 between 8 pin of XTR115 chip and 4 pin.
The port P1.0-1.2 of described microprocessor is connected with LCD MODULE.Operational amplifier U2, U3, U4 adopt the dual operational amplifier AD 8506 of Micro Energy Lose.
The utility model comprises the direct current signal DC 4 ~ 20mA gathering the pressure transducer of pressure signal, low-power microprocessor, the LCD MODULE of specific customization, communication output interface, special chip U1, two-wire system outputting standard.Special chip U1 exports 2 groups of source of stable pressure, 5V and 2.5V, mainly powers to LCD MODULE, pressure transducer, and carries V/I conversion; Micro Energy Lose microprocessor, carry 10 A/D change-over circuits, by software optimization process, display measurement precision can control within 0.2%FS; Communication output module, RS485 communication modes, Modbus-RTU agreement, can directly can be connected with industrial computer by 485 turns of 232 or 485 turns of USB; By button operation, the parameters such as range, unit, scaling position can also be shown by amendment pressure unit arbitrarily; Both can accomplish on-the-spot display, again can electric current long-distance transmissions, can also directly RS485 communication interface PLC, industrial computer etc., be widely used in the fields such as oil, chemical industry, pharmacy, food, papermaking and need pressure to show the occasion of monitoring.
Accompanying drawing explanation
Fig. 1 is the utility model schematic diagram
Fig. 2 is the utility model circuit connection diagram
1-pressure transducer, 2-microprocessor, 3-LCD MODULE, 4-PWM signal processing module, 5-communication output module, 6-XTR115 chip, 7-button design module.
Embodiment
Below in conjunction with explanation the drawings and specific embodiments, the utility model is described in further detail:
The utility model provides a kind of intelligent digital pressure unit, comprise pressure transducer 1, microprocessor 2, LCD MODULE 3, pwm signal processing module 4, communication output module 5, XTR115 chip 6, button design module 7, the output terminal of XTR115 chip is connected with the input end of pressure transducer, the input end of XTR115 chip is connected with the output terminal of pwm signal processing module, the output terminal of microprocessor and LCD MODULE, pwm signal processing module is connected with the input end of communication output module, the output terminal of microprocessor and pwm signal processing module, communication output module is connected with the input end of LCD MODULE.XTR115 chip has the stabilized voltage supply output that 2 groups of voltages are 5V and 2.5V, and mainly give LCD MODULE, communication output module, button design module, pressure transducer provide power supply.XTR115 chip carries V/I change-over circuit and two-wire system electric current DC 4 ~ 20mA exports, and electric current exports formula I out=100Vin/Rin=100 × (VU4-1/R15+Vref2.5/R16)
In technique scheme, microprocessor is MSP430 single-chip microcomputer.The utility model comprises operational amplifier U2, U3, U4, and above-mentioned operational amplifier adopts the dual operational amplifier AD 8506 of Micro Energy Lose.
In technique scheme, XTR115 chip is connected with operational amplifier U2, and 1 pin of XTR115 chip is connected with 5 pin of operational amplifier U2 through resistance R1, and 5 pin of operational amplifier U2 are through resistance R2 ground connection, and resistance R2 two ends are parallel with electric capacity C2.7 pin of operational amplifier U2 are connected with 6 pin, 3 pin respectively.3 pin of operational amplifier U2 are through resistance R3 ground connection.Feedback resistance Rs is connected with between 2 pin of operational amplifier U2 and 1 pin.Pressure transducer comprises the Hui Sitong bridge circuit be made up of 4 adjustable resistances, described Hui Sitong bridge circuit input voltage is the feedback resistance Rs both end voltage of operational amplifier U2, and described Hui Sitong bridge circuit output terminal is connected with the pin P2.1 of microprocessor through operational amplifier U3.3 pin of operational amplifier U2 and 5 pin are input end.2 pin of operational amplifier U3 are through resistance R4 ground connection, and 2 pin are connected by resistance R5 with 1 pin, and 1 pin is connected by resistance R6 with 6 pin, and 6 pin are connected by resistance R7 with 7 pin.7 pin of operational amplifier U3 are connected with the pin P2.1 of microprocessor through resistance R8.The pin P2.1 of microprocessor is through electric capacity C3 ground connection.Pressure transducer adopts piezoresistive pressure sensor, and it is equivalent to a Wheatstone bridge.In order to reduce power consumption, by pressure sensor design on the feedback resistance RS of operational amplifier U2 amplifier, it is made to produce driving voltage V+ and as the input voltage of pressure transducer.Along with the change of pressure, the Wheatstone bridge output signal of pressure transducer also changes.Signal directly amplifies by operational amplifier U3, is directly inputted on U6 microprocessor input mouth 9.Microprocessor U6 will export pwm signal processing module, LCD MODULE and communication output module to after the signal transacting received.Microprocessor U6 adopts the microprocessor of the MSP430 series of Micro Energy Lose, carry 10 A/D conversion electric powers, operating voltage can be accomplished very low, be generally 1.8 ~ 3.6V, receive from after the input signal of pressure transducer, by software optimization process, display measurement precision can control within 0.2%FS.
In technique scheme, pwm signal processing module comprise by resistance R10 and the pi type filter that forms of electric capacity C4, C5 and the pin P1.3 of operational amplifier U4, microprocessor U6 be connected with 5 pin of operational amplifier U4 with pi type filter through resistance R9.6 pin of operational amplifier U4 are connected with 7 pin, and 7 pin are connected with 3 pin through resistance R11.3 pin of operational amplifier U4 are through resistance R12 ground connection, and resistance R12 two ends are parallel with electric capacity C6.2 pin of operational amplifier U4 are through resistance R13 ground connection, and 2 pin are connected with 1 pin through resistance R14, and resistance R14 two ends are parallel with electric capacity C7.1 pin of operational amplifier U4 is connected with 2 pin of XTR115 chip through resistance R15.1 pin of XTR115 chip is connected with 2 pin through resistance R16.XTR115 chip reference voltage Vref=2.5V, provides a part of signal to input by resistance R16; The output terminal of operational amplifier U4 provides a part of signal to input by resistance R15.While microprocessor U6 exports PWM square-wave signal, the signal after A/D can being changed converts frequency signal to and exports.When input pressure changes, the frequency that pwm signal exports is constant, and just pulsewidth changes, namely changes the dutycycle of waveform.Then pwm signal is by the secondary RC filtering of pi type filter, converts d. c. voltage signal to, then by after the amplification process of operational amplifier U4, outputs signal and enter XTR115 chip U1 by resistance R15.
In technique scheme, 8 pin of XTR115 chip are connected with three terminal regulator U5.7133 stabilivolts that three terminal regulator U5 adopts comprise voltage input end, voltage output end and earth terminal, and 5V voltage transitions is directly become 3.3V voltage by three terminal regulator U5, and its 5V voltage input end is through electric capacity C8 ground connection, and 3.3V voltage output end is through electric capacity C9 ground connection.Output voltage the powering with communication integrated package U7 to microprocessor U6 of 3.3V, powers to the special liquid crystal board of LCD MODULE through current-limiting resistance R30 simultaneously.
In technique scheme, the P3.0-3.2 pin of microprocessor controls button K1, K2, K3 with three respectively and is connected, and three key control switch K1, K2, K3 are connected with 3.3V supply voltage through resistance respectively.The parameters such as pressure transmitter measurement range, the unit of display, scaling position can be revised arbitrarily by button operation.
In technique scheme, the P3.4-3.6 pin of microprocessor is connected with communication output integration block, and communication output integration block U7 adopts SP485 chip, adopts RS485 communication modes, Modbus-RTU agreement.1 pin of SP485 chip is connected with the P3.5 port of microprocessor, and 4 pin of SP485 chip are connected with the P3.4 port of microprocessor, and 8 pin of SP485 chip are connected through resistance with 6 pin, 7 pin resistance groundeds of SP485 chip, the direct ground connection of 5 pin of SP485 chip.87 pin of SP485 chip and 6 pin are the utility model communication output terminal.The utility model directly can be connected with industrial computer by 485 turns of 232 or 485 turns of USB; Communication baud rate is defaulted as conventional 9600bps.
In technique scheme, 5,6,7 pin of XTR115 chip are connected with the emitter of triode Q1, base stage and collector respectively, 8 pin of XTR115 chip are connected with 24V positive source through diode D1,4 pin of XTR115 chip are connected with 24V power cathode, are connected with electric capacity C1 between 8 pin of XTR115 chip and 4 pin.The both positive and negative polarity of 24V power supply exports the direct current of 4-20mA.
In technique scheme, the port P1.0-1.2 of microprocessor is connected with LCD MODULE.The liquid crystal board of LCD MODULE is special customized, adopts HT1621 as LCD driving chip, positive four LCD design, maximum indication range-1999 ~ 9999.Separately be designed with four kinds of scaling positions such as unit of display KPa, MPa, m (keeping for liquid level, rice), DEG C (keep for temperature, degree Celsius), any selection, can be with at most 3 radix point, i.e. integer, one 0.0, two 0.00, three 0.000.
In technique scheme, operational amplifier U2, U3, U4 adopt the dual operational amplifier AD 8506 of Micro Energy Lose.
The utility model all adopts software calibration, without potentiometer design, has the range of the menu of calibration, input calibration, correction power transmitter in actions menu, adopts 2 point type calibrations, directly calibrates minimum pressure zero point and maximum pressure range two end point signal.Export calibration, school output signal DC 4 ~ 20mA also adopts 2 point type calibrations, directly calibration exports 4mA zero point and 20mA full scale.The range change of output signal directly linearly changes with the change of digital display range, shows and export one-to-one relationship.
Because be adopt software calibration, without potentiometer design thus before formal calibration, must simply judge the correctness of hardware when hardware appearance exception time, to there will be the phenomenon that cannot calibrate; So devise several monitoring point in whole circuit, judge that whether hardware circuit is normal.As the inspection of source of stable pressure, 5V, 3.3V, 2.5V etc., check that the 7 pin voltages of operational amplifier U2, U3, U4 export and 1 pin voltage exports respectively simultaneously.In order to improve antijamming capability, product design software filtering, make product show applicability that is more stable, reliable, that improve product.
Obviously, those skilled in the art can carry out various change and modification to the utility model and not depart from spirit and scope of the present utility model.Like this, if these amendments of the present utility model and modification belong within the scope of the utility model claim and equivalent technologies thereof, then the utility model is also intended to comprise these change and modification.The content be not described in detail in this instructions belongs to the known prior art of professional and technical personnel in the field.
Claims (10)
1. an intelligent digital pressure unit, it is characterized in that comprising pressure transducer, microprocessor, LCD MODULE, pwm signal processing module, communication output module, XTR115 chip, button design module, the output terminal of XTR115 chip is connected with the input end of pressure transducer, the input end of XTR115 chip is connected with the output terminal of pwm signal processing module, the output terminal of microprocessor and LCD MODULE, pwm signal processing module is connected with the input end of communication output module, the output terminal of microprocessor and pwm signal processing module, communication output module is connected with the input end of LCD MODULE.
2. intelligent digital pressure unit according to claim 1, is characterized in that microprocessor is MSP430 single-chip microcomputer.
3. intelligent digital pressure unit according to claim 2, it is characterized in that 1 pin of XTR115 chip is connected with operational amplifier U2, pressure transducer comprises the Hui Sitong bridge circuit be made up of 4 adjustable resistances, described Hui Sitong bridge circuit input end is connected with the feedback resistance Rs two ends of operational amplifier U2, and described Hui Sitong bridge circuit output terminal is connected with the pin P2.1 of microprocessor through operational amplifier U3.
4. intelligent digital pressure unit according to claim 2, it is characterized in that pwm signal processing module comprise by resistance R10 and the pi type filter that forms of electric capacity C4, C5 and operational amplifier U4, the pin P1.3 of microprocessor is connected with the input end of pi type filter with operational amplifier U4 through resistance R9, and the output terminal of operational amplifier U4 is connected with 2 pin of XTR115 chip through resistance R15.
5. intelligent digital pressure unit according to claim 2, is characterized in that 8 pin of XTR115 chip are connected with three terminal regulator U5.
6. intelligent digital pressure unit according to claim 2, the P3.0-3.2 pin that it is characterized in that microprocessor respectively with three button control linkages.
7. intelligent digital pressure unit according to claim 2, is characterized in that the P3.4-3.6 pin of microprocessor is connected with communication output integration block, and communication output integration block adopts SP485 chip, adopts RS485 communication modes, Modbus-RTU agreement.
8. intelligent digital pressure unit according to claim 2, it is characterized in that 5 of XTR115 chip, 6,7 pin are connected with the emitter of triode Q1, base stage and collector respectively, 8 pin of XTR115 chip are connected with 24V positive source through diode D1,4 pin of XTR115 chip are connected with 24V power cathode, are connected with electric capacity C1 between 8 pin of XTR115 chip and 4 pin.
9. an intelligent digital pressure unit according to claim 2, its feature is connected with LCD MODULE at the port P1.0-1.2 of microprocessor.
10. an intelligent digital pressure unit according to claim 2, is characterized in that operational amplifier U2, U3, U4 adopt the dual operational amplifier AD 8506 of Micro Energy Lose.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420429645.2U CN204228303U (en) | 2014-07-31 | 2014-07-31 | Intelligent digital pressure unit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420429645.2U CN204228303U (en) | 2014-07-31 | 2014-07-31 | Intelligent digital pressure unit |
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| CN204228303U true CN204228303U (en) | 2015-03-25 |
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| CN201420429645.2U Expired - Fee Related CN204228303U (en) | 2014-07-31 | 2014-07-31 | Intelligent digital pressure unit |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105509955A (en) * | 2015-12-21 | 2016-04-20 | 上海自动化仪表有限公司 | Pressure transmitter based on CMC processor |
| CN105910747A (en) * | 2016-04-26 | 2016-08-31 | 江苏华夏仪表有限公司 | Stress transmitter |
| CN106257255A (en) * | 2016-05-31 | 2016-12-28 | 大庆市镁龙测控技术有限公司 | Electrical pressure transmitter |
| CN107305373A (en) * | 2016-04-25 | 2017-10-31 | 经登企业股份有限公司 | Pressure sensor and control system |
| CN107478377A (en) * | 2016-06-08 | 2017-12-15 | 深圳市艾而特工业自动化设备有限公司 | The digital air gauge that a kind of double pictures are shown |
| CN110514348A (en) * | 2019-09-02 | 2019-11-29 | 武汉松野智能仪表有限公司 | A kind of intelligent digital pressure transmitter circuit |
| CN110514316A (en) * | 2019-09-02 | 2019-11-29 | 武汉松野智能仪表有限公司 | A kind of intelligent digital temperature transmitter circuit |
| CN110567527A (en) * | 2019-09-26 | 2019-12-13 | 武汉松野智能仪表有限公司 | Pressure temperature transmitter circuit based on NB-IoT wireless transmission |
-
2014
- 2014-07-31 CN CN201420429645.2U patent/CN204228303U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105509955A (en) * | 2015-12-21 | 2016-04-20 | 上海自动化仪表有限公司 | Pressure transmitter based on CMC processor |
| CN107305373A (en) * | 2016-04-25 | 2017-10-31 | 经登企业股份有限公司 | Pressure sensor and control system |
| CN105910747A (en) * | 2016-04-26 | 2016-08-31 | 江苏华夏仪表有限公司 | Stress transmitter |
| CN106257255A (en) * | 2016-05-31 | 2016-12-28 | 大庆市镁龙测控技术有限公司 | Electrical pressure transmitter |
| CN107478377A (en) * | 2016-06-08 | 2017-12-15 | 深圳市艾而特工业自动化设备有限公司 | The digital air gauge that a kind of double pictures are shown |
| CN107478377B (en) * | 2016-06-08 | 2023-06-06 | 深圳市艾而特传感器精密有限公司 | Double-picture display digital barometer |
| CN110514348A (en) * | 2019-09-02 | 2019-11-29 | 武汉松野智能仪表有限公司 | A kind of intelligent digital pressure transmitter circuit |
| CN110514316A (en) * | 2019-09-02 | 2019-11-29 | 武汉松野智能仪表有限公司 | A kind of intelligent digital temperature transmitter circuit |
| CN110567527A (en) * | 2019-09-26 | 2019-12-13 | 武汉松野智能仪表有限公司 | Pressure temperature transmitter circuit based on NB-IoT wireless transmission |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20150325 |