CN106404207A - Platinum resistance-based wide-range high-precision temperature measuring instrument and measuring method thereof - Google Patents
Platinum resistance-based wide-range high-precision temperature measuring instrument and measuring method thereof Download PDFInfo
- Publication number
- CN106404207A CN106404207A CN201610978073.7A CN201610978073A CN106404207A CN 106404207 A CN106404207 A CN 106404207A CN 201610978073 A CN201610978073 A CN 201610978073A CN 106404207 A CN106404207 A CN 106404207A
- Authority
- CN
- China
- Prior art keywords
- resistance
- temperature
- circuit
- precision
- platinum resistance
- 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
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
- G01K7/16—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements
- G01K7/18—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The invention discloses a platinum resistance-based wide-range high-precision temperature measuring instrument and a measuring method thereof. The temperature measuring width is between -200 DEG C and 800 DEG C. The platinum resistance-based wide-range high-precision temperature measuring instrument comprises a power circuit (1), a constant current source driving circuit (2), a temperature sensor (3), a signal processing circuit (4), an A/D conversion circuit (5), a single chip microcomputer (6), a display (7), a memory (8), a key module (9), a reset circuit (10), a crystal oscillator circuit (11), a temperature calibration module (12) and a data signal processing module (13). Measurement requirements can be met, the high-precision temperature measuring instrument after calibration has a temperature measurement range of 0 DEG C to 100 DEG C, the temperature measurement precision reaches 5/1000, the temperature measurement precision is high, the temperature measurement range is wide, the price is low, and the economic value and the social value are huge.
Description
Technical field
The present invention relates to the structure design of temperature measuring set and applied technical field, specifically provide one kind and be based on platinum resistance
Wide-range high-precision temperature measuring set and its measuring method.
Background technology
For people, temperature survey understands that temperature, application temperature provide foundation, have widely in actual production life
Application, its range of application is from daily life to scientific research.High-resolution hydrocode technology is to improve to ambient temperature
The key controlling, this allows for high-resolution hydrocode technology becomes the factor that can not ignore in industrial development.Thus design
The wide High Precision Temperature Measuring Instruments of a kind of high precision, temperature-measuring range are very important, and this is greatly promoted our societies
Development, the productive life giving people brings great convenience.
People are highly desirable to obtain a kind of excellent High Precision Temperature Measuring Instruments of technique effect.
Content of the invention
It is an object of the invention to provide a kind of wide-range high-precision temperature measuring set based on platinum resistance and its measuring method.
The described wide-range high-precision temperature measuring set based on platinum resistance and its measuring method composition are as follows：Power circuit 1,
Constant current source driving circuit 2, temperature sensor 3, signal processing circuit 4, A/D change-over circuit 5, single-chip microcomputer 6, display 7, bin
8th, key-press module 9, reset circuit 10, crystal oscillating circuit 11, temperature correction module 12, data signal processing module 13；Wherein, power supply
Circuit 1 and constant current source driving circuit 2, A/D change-over circuit 5 and single-chip microcomputer 6 constitute and electrically connect, constant current source driving circuit 2 and signal
Process circuit 4 constitutes electrical connection, and described signal processing circuit 4 includes connecting the equivalent resistance of four leads of temperature sensor 3,
It is respectively first resistor, second resistance, 3rd resistor and the 4th resistance, wherein, first resistor, constant current source driving circuit 2, second
Resistance and temperature sensor 3 are followed in series to form loop by wire, and one end of 3rd resistor is connected to the first electricity by wire
Between resistance and temperature sensor 3, the other end of 3rd resistor connects the A/D sampling compensating line of A/D change-over circuit 5, the 4th resistance
One end be connected between second resistance and temperature sensor 3 by wire, the other end of the 4th resistance connects compensating line over the ground,
Signal processing circuit 4 is connected with single-chip microcomputer 6 by A/D change-over circuit 5, display 7, bin 8, key-press module 9, reset circuit
10 are connected with single-chip microcomputer 6 respectively with crystal oscillating circuit 11, and key-press module 9 passes through temperature correction module 12 and processes mould with data signal
Block 13 is connected, and data signal processing module 13 is connected with single-chip microcomputer 6.
Described temperature sensor 3 adopts PT100 platinum sensor, and described constant current source driving circuit 2 connects temperature stabilization
The high high-accuracy resistance of coefficient, the temperature varying coefficient of this high-accuracy resistance is 1ppm, i.e. 1 DEG C of temperature change, its change in resistance
For 106Ω, the electric current of described constant current source driving circuit 2 output can not be more than 4mA.
Described A/D change-over circuit 5 adopts the LTC2492 analog-digital converter of 24, and its precision is up to VREF/224.
Described measuring method according to the put variation of ambient temperature of platinum resistance and resistance close to linear relation, by thermometric
Scope is divided into some sections, and each of which section is linear, and up to 1mK, signal processing circuit 4 employs and changes the resolution of PT100
The four-wire system connection entered, collection platinum resistance voltage and reference voltage simultaneously, and with constant-current source for circuit provide one stable, hold
Continuous electric current, eliminates due to accessing the error of lead resistance and temperature drift that platinum resistance exciting current causes is to thermometric shadow
Ring.Data processing adopts Function Approximation Algorithm and temperature correction algorithm, each section of temperature is chosen at 2 points and is corrected, therefore manage
By computational accuracy up to 0.001 DEG C.
Described A/D change-over circuit 5 adopts the LTC2492 analog-digital converter of 24, and its precision is up to VREF/224, VREFAbout etc.
In 1.1V, using formula Rt=R0(1+At+Bt2+C(t-100)t3) and formula Rt=(1+At+Bt2) adopt numerical approximation algorithm
Solve.
When the ambient temperature that platinum resistance is placed changes between -200 DEG C～800 DEG C, its put variation of ambient temperature
With resistance close to linear relation.National regulations PT platinum resistance when 0 DEG C, its resistance value R0=100 Ω, its characteristic curve
As shown in Figure 1.
Platinum resistance mainly has resistance and allows two kinds of errors.Wherein A allowable error is equal to ± (0.15+0.002t), and B allows
Error is equal to ± (0.30+0.005t), and in formula, t represents temperature value.
When -200 DEG C≤t≤0 DEG C, the resistance of platinum resistance with the function expression of temperature change is：
Rt=R0(1+At+Bt2+C(t-100)t3) (1)
When 0 DEG C≤t≤850 DEG C, the resistance of platinum resistance with the function expression of temperature change is：
Rt=(1+At+Bt2) (2)
In formula, RtThe resistance value of platinum resistance, R when representing t DEG C0The resistance value of platinum resistance, this paper design process when representing 0 DEG C
The resistance of middle selection is Pt, the R of standard Pt0Equal to ohm.The value of A, B, C is respectively：A=3.9082 × 10-3, B=-
5.80195×10-7, C=-4.2735 × 10-12.
Numerical approximation algorithm is utilized according to above-mentioned principle, takes an array to have following data, set array in program as T
(K) 24 data, are had in this array, data is as follows：
8388.608,4194.304,2097.152,1048.576,0524.288,0262.144,0131.072,
0065.536,0032.768,0016.384,0008.192,0004.096,0002.048,0001.024,0000.512,
0000.256,0000.128,0000.064,0000.032,0000.016,0000.008,0000.004,0000.002,
0000.001.
Program adopts cycle accumulor mode, as K=1,8388.608 is brought in formula (2), calculates resistance value, will
This value RTPlatinum resistance resistance R with actual measurementPT100It is compared, if bigger than actual measurement resistance value, i.e. RT＞ RPT100,
Then, this data is not added up, if less than actual measurement resistance value, i.e. RT＜ RPT100, then, this data is added up.Once
Circulation 24 times, T (K) value meeting above-mentioned condition the most at last is added, and obtains the value of calculation of platinum resistance temperature.
Described signal processing circuit 4 uses the four-wire system connection after improvement, for ensureing the precision of measurement and stablizing
Degree.X in Fig. 51、X2、X3、X4It is the equivalent resistance of four leads of platinum sensor respectively.With R4The magnitude of voltage of resistance as
Reference voltage R in the design4Value is 510 Ω, reference voltage, the design of constant-current source drastically influence circuit survey
Accuracy of measurement and degree of stability.Reference voltage VREFWhether stablize and Low Drift Temperature is to ensure that high precision measuring temperature instrument herein has height
The important prerequisite of precision.External interference is reduced with the mirror current source that audion 8550 is constituted, it is to avoid error.On this basis
Connect high-accuracy resistance R0, the temperature varying coefficient of this high-accuracy resistance is 1ppm, i.e. 1 DEG C of temperature change, and its change in resistance is
10-6Ω, R in the design0Value is Ω.Theoretical according to electronic circuit, the electric current I of platinum resistance PT sensor is：
Reference voltage VREFFor：
VRef=I × R4(4)
The voltage of PT sensor and precision resistance R0Voltage be respectively：
VPT100=I × RPT100(5)
VR0=I × R0(6)
Finally take voltage and the precision resistance R obtaining PT sensor0Both voltage voltage ratio, that is,
Thus, eliminate the curent change that constant-current source affected due to factors such as temperature drifts so that output voltage ratio with
Platinum resistance becomes good linear relationship.
The voltage signal obtaining is sampled by 24 A/D converter LTC2492, then by signal to ATmega32
Single-chip microcomputer, single-chip microcomputer carries out data processing and preserves and video data.The stability of the design temperature measurement of this circuit can reach
To 1 ‰.
The present invention, using ATmega32 single-chip microcomputer as the core devices of control circuit, has selected 24 LTC2492 as A/D
Transducer, PT100 has been selected in temperature sensor, thermometric width at -200 DEG C～800 DEG C, because PT100 sensor allows to pass through
The not higher than electric current of 4mA, minimum placed-depth can not be less than 200mm, and its precision is up to 1mK, is hindered with resistance using PT100 temperature
The change of value and linearly change, sample circuit employs improved four-wire system connection, simultaneously collection platinum resistance voltage and reference
Voltage, and with constant-current source be circuit provide a stable, lasting electric current, eliminate due to access lead resistance error and
The temperature drift that platinum resistance exciting current causes is on thermometric impact.Data processing adopts Function Approximation Algorithm and temperature correction to calculate
Method, thus realizing high-resolution hydrocode, Theoretical Calculation precision is up to 0.001 DEG C.
The present invention meets measurement requirement, interval 0 DEG C～100 DEG C in thermometric of the High Precision Temperature Measuring Instruments after calibration, thermometric
Precision reaches 5/1000ths.Temperature measurement accuracy is high, temperature-measuring range is wide, price is low, has more huge economic worth and social valency
Value.
Brief description
Fig. 1 is the characteristic curve of platinum resistance；
Fig. 2 is measurement temperature schematic diagram；
Fig. 3 is based on the wide-range high-precision temperature measuring set of platinum resistance and its schematic diagram of measuring method；
Fig. 4 is platinum resistance four-wire system wiring diagram；
Fig. 5 is constant current source driving circuit figure；
Fig. 6 is the schematic diagram of LTC2492；
The circuit diagram of Fig. 7 key-press module；
The wide-range high-precision temperature measuring set based on platinum resistance for the Fig. 8 and its measuring method workflow diagram；
Specific embodiment
As shown in figure 3, power circuit 1, constant current source driving circuit 2, temperature sensor 3, signal processing circuit 4, A/D conversion
Circuit 5, single-chip microcomputer 6, display 7, bin 8, key-press module 9, reset circuit 10, crystal oscillating circuit 11, temperature correction module 12,
Data signal processing module 13；Wherein, power circuit 1 and constant current source driving circuit 2, A/D change-over circuit 5 and single-chip microcomputer 6 are constituted
Electrical connection, constant current source driving circuit 2 and signal processing circuit 4 constitute electrical connection, and described signal processing circuit 4 includes connecting temperature
The equivalent resistance of four leads of sensor 3, respectively first resistor, second resistance, 3rd resistor and the 4th resistance, wherein,
First resistor, constant current source driving circuit 2, second resistance and temperature sensor 3 are followed in series to form loop by wire, the 3rd electricity
One end of resistance is connected between first resistor and temperature sensor 3 by wire, and the other end of 3rd resistor connects A/D conversion electricity
The A/D sampling compensating line on road 5, one end of the 4th resistance is connected between second resistance and temperature sensor 3 by wire, and the 4th
The other end of resistance connects compensating line over the ground, and signal processing circuit 4 is connected with single-chip microcomputer 6 by A/D change-over circuit 5, display
7th, bin 8, key-press module 9, reset circuit 10 are connected with single-chip microcomputer 6 respectively with crystal oscillating circuit 11, and key-press module 9 passes through temperature
Degree calibration module 12 is connected with data signal processing module 13, and data signal processing module 13 is connected with single-chip microcomputer 6.
Described A/D change-over circuit 5 adopts the LTC2492 analog-digital converter of 24, and its precision is up to VREF/224, VREFAbout etc.
In 1.1V, using formula Rt=R0(1+At+Bt2+C(t-100)t3) and formula Rt=(1+At+Bt2) adopt numerical approximation algorithm
Solve.
Described key-press module 9 includes 4 control keys, specially 1 esc key, 1 ↑ directionkeys and 1 ↓ directionkeys, 4
One end ground connection, another termination I/O mouth and the pull-up resistor of control key.
As shown in figure 1, when the ambient temperature that platinum resistance is placed changes between -200 DEG C～800 DEG C, its put ring
Border temperature change and resistance are close to linear relation.National regulations PT platinum resistance when 0 DEG C, its resistance value R0=100 Ω,
Its characteristic curve is as shown in Figure 1.
Platinum resistance mainly has resistance and allows two kinds of errors.Wherein A allowable error is equal to ± (0.15+0.002t), and B allows
Error is equal to ± (0.30+0.005t), and in formula, t represents temperature value.
When -200 DEG C≤t≤0 DEG C, the resistance of platinum resistance with the function expression of temperature change is：
Rt=R0(1+At+Bt2+C(t-100)t3) (1)
When 0 DEG C≤t≤850 DEG C, the resistance of platinum resistance with the function expression of temperature change is：
Rt=(1+At+Bt2) (2)
In formula, RtThe resistance value of platinum resistance, R when representing t DEG C0The resistance value of platinum resistance, this paper design process when representing 0 DEG C
The resistance of middle selection is Pt, the R of standard Pt0Equal to ohm.The value of A, B, C is respectively：A=3.9082 × 10-3, B=-
5.80195×10-7, C=-4.2735 × 10-12.
Numerical approximation algorithm is utilized according to above-mentioned principle, takes an array to have following data, set array in program as T
(K) 24 data, are had in this array, data is as follows：
8388.608,4194.304,2097.152,1048.576,0524.288,0262.144,0131.072,
0065.536,0032.768,0016.384,0008.192,0004.096,0002.048,0001.024,0000.512,
0000.256,0000.128,0000.064,0000.032,0000.016,0000.008,0000.004,0000.002,
0000.001.
Program adopts cycle accumulor mode, as K=1,8388.608 is brought in formula (2), calculates resistance value, will
This value RTPlatinum resistance resistance R with actual measurementPT100It is compared, if bigger than actual measurement resistance value, i.e. RT＞ RPT100,
Then, this data is not added up, if less than actual measurement resistance value, i.e. RT＜ RPT100, then, this data is added up.Once
Circulation 24 times, T (K) value meeting above-mentioned condition the most at last is added, and obtains the value of calculation of platinum resistance temperature.
So simple linear relationship is not met always between platinum resistance temperature and resistance, by other conditions in reality
Impact, has deviation.
High precision measuring temperature instrument selects platinum resistance as temperature transducer, and platinum resistance selects improved four-wire system wiring method, can
It is prevented effectively from the error that lead resistance is brought to temperature survey.By constant current source to platinum resistance provide one stable, lasting
Electric current, the change in resistance that platinum resistance is caused in temperature changing process is sent to A/D converter conversion after being transformed into the signal of telecommunication
Become digital signal, then receive via single-chip microcomputer, analyze, process and result of calculation is corrected, single-chip microcomputer is extraneous if necessary
Key-press module can carry out initialization operation to system, the data finally processing single-chip microcomputer passes through numeral method out.Its
Operation principle is as shown in Figure 2.
The temperature sensor of platinum resistance PT100 is to be made according to the characteristic that platinum resistance varies with temperature, when environment temperature to be measured
When degree changes, the resistance of platinum resistance also changes therewith, thus temperature signal is converted into resistance signal, then by detecting platinum
Resistance signal is converted into voltage signal by the magnitude of voltage of resistance.The LTC2492 A/D converter of 24 is respectively to platinum resistance PT
The voltage of voltage and high-accuracy resistance is read out, and the voltage signal of reading is converted into digital signal.Digital signal transmits
To ATMEGA32 single-chip microcomputer, microprocessor can be entered to digital signal according to the program write with Function Approximation Algorithm for core in advance
Row parsing computing, thus obtaining the measurement temperature of environment to be measured, finally by the temperature of numeral method measurement.
Described signal processing circuit 4 adopts the four-wire system mode of connection, refers to that temperature sensor 3 is the both sides difference of platinum resistance
Connect and draw two wires, be a kind of high-precision temp measuring method.The external A/D sampling of its difference on two-wire system mode of connection is mended
Repay line and an A/D compensating line over the ground.The change transitions of platinum resistance are become the signal of telecommunication by the wire of wherein platinum resistance one end, and other two
The signal of telecommunication is sent to signal processor by bar wire.The impact of lead resistance is cut down by such mode of connection completely, can be used for
High precision, apart from remote place.Note the current control exporting constant-current source within 4mA, it is to avoid electric current is excessive to be led to simultaneously
Platinum resistance is overheated and brings error to measurement.
Constant-current source resistance itself is infinitely great, has the characteristics that independent of temperature variations, thus being widely used in circuit
Design among, its Main Function is to provide a constant current not changed with load change for designed circuit.?
Need accurately to record the situation of change of platinum resistance resistance, so that can be by change in resistance in the design circuit of high precision measuring temperature instrument
It is transformed into the signal of telecommunication, thus being converted into digital signal, thus obtaining the temperature of environment to be measured.Constant-current source is accurately to record platinum resistance
The precondition of resistance.
Reference voltage, the design of constant-current source drastically influence certainty of measurement and the degree of stability of circuit.Reference electricity
Pressure VREFWhether stablize and Low Drift Temperature is to ensure that high precision measuring temperature instrument herein has high-precision important prerequisite；Meanwhile, it is employing
The platinum resistance temperature sensor of the four-wire system mode of connection provides stable constant-current source to be also necessary, and platinum resistance temperature
Sensor by electric current definitely not above 4mA.
As shown in figure 4, described signal processing circuit 4 uses the four-wire system connection after improvement, for ensureing measurement
Precision and degree of stability.X in Fig. 51、X2、X3、X4It is the equivalent resistance of four leads of platinum sensor respectively.With R4Resistance
Magnitude of voltage R in the design as reference voltage4Value is 510 Ω, and reference voltage, the design of constant-current source drastically influence
The certainty of measurement of circuit and degree of stability.Reference voltage VREFWhether stablize and Low Drift Temperature is to ensure that high precision measuring temperature herein
Instrument has high-precision important prerequisite.External interference is reduced with the mirror current source that audion 8550 is constituted, it is to avoid error.?
Connect on the basis of this high-accuracy resistance R0, the temperature varying coefficient of this high-accuracy resistance is 1ppm, i.e. 1 DEG C of temperature change, its resistance
Value changes are 10-6Ω, R in the design0Value is Ω.Theoretical according to electronic circuit, the electric current I of platinum resistance PT sensor is：
Reference voltage VREFFor：
VRef=I × R4(4)
The voltage of PT sensor and precision resistance R0Voltage be respectively：
VPT100=I × RPT100(5)
VR0=I × R0(6)
Finally take voltage and the precision resistance R obtaining PT sensor0Both voltage voltage ratio, that is,
Thus, eliminate the curent change that constant-current source affected due to factors such as temperature drifts so that output voltage ratio with
Platinum resistance becomes good linear relationship.
The voltage signal obtaining is sampled by 24 A/D converter LTC2492, then by signal to ATmega32
Single-chip microcomputer, single-chip microcomputer carries out data processing and preserves and video data.The stability of the design temperature measurement of this circuit can reach
To 1 ‰.
Table 1 High Precision Temperature Measuring Instruments emulate data
Design circuit according to Fig. 5 and Fig. 3 system structure FB(flow block), the system circuit test is verified change current potential
The resistance of device, to simulate platinum resistance temperature sensor test, measures potentiometer using the desk-top multimeter 8808A of fluke five and half
Resistance calibrated, take part measurement data as shown in table 1.According to table 1 systematic survey sampled data, V100It is to represent accurate
Resistance R0Voltage, VPT100It is the voltage of platinum sensor, the resistance of platinum sensor can be calculated by formula (7), then lead to
Cross formula (1) and formula (2) solves measured temperature.Calculate through data, mean error 1.1 ‰, maximum error 4 ‰.
For ensureing precision and the degree of stability of measurement, we devise one and do reference voltage with 510 ohmages, with three poles
The mirror current source that pipe 8550 is constituted is reducing external interference, it is to avoid error.One ohm of series connection is high-accuracy on this basis
Resistance, 1 DEG C of temperature change, the increased resistance value of this high-accuracy resistance is 106/ mono-.For ensureing the high accuracy survey designing herein
The temperature measurement accuracy of amount instrument and degree of stability, we take the method that analog voltage does ratio using the high-accuracy resistance of ohm and PT respectively
Obtain magnitude of voltage.Its circuit design is referring to Fig. 5.
Described A/D change-over circuit 5 Main Function is that analogue signal is become digital signal, the system independent design A/D
Transducer.What ADC selected is voltage resolution is 0.5LSB, 1LSB=VREF/224, VREFSpan be 0.1～VCC,24
The LTC2492 of position, it complies fully with the requirement to precision for the system, and the design of LTC2492 is as shown in Figure 6.
For convenience of the parameter setting of high precision measuring temperature instrument and the calibration of temperature, ad hoc meter key-press module 9, key-press module 9 wraps
Containing 4 control buttons, their function is ESC, ENTER, both direction key respectively.For realizing the control function of circuit, 4 controls
Button one end processed ground connection, another termination I/O mouth and pull-up resistor.On keyboard, each button is equal to a mechanical switch, when
When key is pressed, circuit is in connected state, and now corresponding to single-chip microcomputer mouth line is low level；When button is released, whole circuit
It is off, now mouth line corresponding with single-chip microcomputer is high level.The circuit of key-press module is as shown in Figure 7.
Key-press module 9, using free-standing button, can be directly connected to into single key circuit with I/O line, each button list
Solely connect an I/O mouth line, be in separate state, this key arrangement avoids producing impact to other I/O mouth lines.This electricity
Road figure be designed with Low level effective, when button disconnects, pull-up resistor ensure that I/O mouth line has high level.
Temperature correction module 12 is mainly used in the numerical value to measured temperature and carries out linear gauging, the temperature value that system is surveyed
Mainly the error caused by the difference of sensor, the difference of constant-current source, analog-digital converter and solution temperature equation are produced error
The composition such as raw error, comprehensive apparently these are linear, and useable linear equation is being modified.Its update equation computing formula
For：Y=ax+b, needs before calculating first to determine two parameters of a and b in equation, by with two-point measurement value and standard temperature value
Method relatively can try to achieve two parameters of a and b, and x is substituted into formula：In y=ax+b, the y solving is exactly revised result.?
During determining two parameters of a and b, preferably select 0 DEG C and 100 DEG C of two points as two-point measurement value.
When -200 DEG C≤t≤0 DEG C, the resistance of platinum resistance with the function expression of temperature change is：
Rt=R0(1+At+Bt2+C(t-100)t3) (1)
When 0 DEG C≤t≤850 DEG C, the resistance of platinum resistance with the function expression of temperature change is：
Rt=(1+At+Bt2) (2)
By system compensation.Temperature measuring set test data is as shown in table 2 and table 3.
Mixture of ice and water final test data after table 2 calibration
Boiling water final test data after table 3 calibration
According to the characteristic curve of platinum resistance, its update equation computing formula is：Y=ax+b.By temperature correction parameter journey
The numerical value of ordered pair measured temperature carries out linear gauging, consider error caused by the difference of constant-current source, analog-digital converter with
And the produced error useable linear equation of solution temperature equation etc. is being modified.Need before calculating first to determine a and b in equation
Two parameters, we select 0 DEG C can to try to achieve two parameters of a and b by the method being compared with standard temperature value with two-point measurement value
To solve two parameters of a and b with 100 DEG C of two points as two-point measurement value, x is substituted into formula：In y=ax+b, the y solving is just
It is revised result.
The described wide-range based on platinum resistance be can be seen that by the measurement data of temperature measuring set before and after comparison calibration high
Accurate temperature measuring instrument and its measuring method meet measurement requirement, interval 0 DEG C in thermometric of the High Precision Temperature Measuring Instruments after calibration
～100 DEG C, temperature measurement accuracy reaches 5/1000ths.Temperature measurement accuracy is high, temperature-measuring range is wide, price is low, has more huge economy
It is worth and social value.
Claims (4)
1. a kind of wide-range high-precision temperature measuring set based on platinum resistance it is characterised in that：The described width amount based on platinum resistance
Journey High Precision Temperature Measuring Instruments and its measuring method composition are as follows：Power circuit (1), constant current source driving circuit (2), temperature sensing
Device (3), signal processing circuit (4), A/D change-over circuit (5), single-chip microcomputer (6), display (7), bin (8), key-press module
(9), reset circuit (10), crystal oscillating circuit (11), temperature correction module (12), data signal processing module (13)；Wherein, power supply
Circuit (1) is electrically connected with constant current source driving circuit (2), A/D change-over circuit (5) and single-chip microcomputer (6) composition, constant current source driving circuit
(2) electrically connect with signal processing circuit (4) composition, described signal processing circuit (4) includes connect temperature sensor (3) four
The equivalent resistance of lead, respectively first resistor, second resistance, 3rd resistor and the 4th resistance, wherein, first resistor, constant current
Source driving circuit (2), second resistance and temperature sensor (3) are followed in series to form loop, one end of 3rd resistor by wire
It is connected between first resistor and temperature sensor (3) by wire, the other end of 3rd resistor connects A/D change-over circuit (5)
A/D sampling compensating line, one end of the 4th resistance is connected between second resistance and temperature sensor (3) by wire, the 4th
The other end of resistance connects compensating line over the ground, and signal processing circuit (4) is connected with single-chip microcomputer (6) by A/D change-over circuit (5),
Display (7), bin (8), key-press module (9), reset circuit (10) are connected with single-chip microcomputer (6) respectively with crystal oscillating circuit (11)
Connect, key-press module (9) is connected with data signal processing module (13) by temperature correction module (12), data signal processing module
(13) it is connected with single-chip microcomputer (6).
2. according to the wide-range high-precision temperature measuring set based on platinum resistance described in claim 1 it is characterised in that：Described temperature
Sensor (3) adopts PT100 platinum sensor, and it is 1ppm's that described constant current source driving circuit (2) connects temperature varying coefficient
The high high-accuracy resistance of temperature stabilization coefficient, the electric current that described constant current source driving circuit (2) exports can not be more than 4mA.
3. according to the wide-range high-precision temperature measuring set based on platinum resistance described in claim 1 or 2 it is characterised in that：Described
A/D change-over circuit (5) adopts the LTC2492 analog-digital converter of 24, and its precision is up to VREF/224.
4. according to the wide-range high-precision temperature measuring set based on platinum resistance and its measuring method, its feature described in claim 2
It is：Described measuring method according to the put variation of ambient temperature of platinum resistance and resistance close to linear relation, by thermometric model
Enclose and be divided into some sections, each of which section is linear, up to 1mK, signal processing circuit (4) employs and changes the resolution of PT100
The four-wire system connection entered, collection platinum resistance voltage and reference voltage simultaneously, and with constant-current source for circuit provide one stable, hold
Continuous electric current, eliminates due to accessing the error of lead resistance and temperature drift that platinum resistance exciting current causes is to thermometric shadow
Ring.Data processing adopts Function Approximation Algorithm and temperature correction algorithm, each section of temperature is chosen at 2 points and is corrected, therefore manage
By computational accuracy up to 0.001 DEG C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610978073.7A CN106404207B (en) | 2016-11-08 | 2016-11-08 | Wide-range high-precision temperature measuring instrument based on platinum resistor and measuring method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610978073.7A CN106404207B (en) | 2016-11-08 | 2016-11-08 | Wide-range high-precision temperature measuring instrument based on platinum resistor and measuring method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106404207A true CN106404207A (en) | 2017-02-15 |
| CN106404207B CN106404207B (en) | 2020-04-03 |
Family
ID=58015316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610978073.7A Expired - Fee Related CN106404207B (en) | 2016-11-08 | 2016-11-08 | Wide-range high-precision temperature measuring instrument based on platinum resistor and measuring method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106404207B (en) |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106989847A (en) * | 2017-03-22 | 2017-07-28 | 中国计量大学 | Error correcting method in system of Pt-resistance |
| CN106989844A (en) * | 2017-04-26 | 2017-07-28 | 北京科技大学 | A kind of data acquisition equipment and acquisition method |
| CN107943180A (en) * | 2017-11-20 | 2018-04-20 | 中国电子科技集团公司第四十研究所 | A kind of circuit and method for suppressing reference circuit voltage drift |
| CN108037790A (en) * | 2017-11-30 | 2018-05-15 | 天津航空机电有限公司 | A kind of platinum resistance signal acquisition debug circuit based on double constant-current sources |
| CN109991295A (en) * | 2019-04-29 | 2019-07-09 | 福建海纳欣生物科技有限公司 | A kind of intelligent pH combination electrode and its implementation with temperature drift self-regulation |
| CN110632959A (en) * | 2019-10-18 | 2019-12-31 | 湖南晨威高科有限公司 | Charging pile internal temperature control method |
| CN111198591A (en) * | 2018-11-16 | 2020-05-26 | 纬湃科技投资(中国)有限公司 | Method for controlling current output of SDH8 circuit |
| CN111257641A (en) * | 2020-02-25 | 2020-06-09 | 东风电子科技股份有限公司 | Wide resistance range signal acquisition circuit and corresponding acquisition method |
| CN111765913A (en) * | 2020-07-22 | 2020-10-13 | 中国科学院长春光学精密机械与物理研究所 | Absolute measuring ring photoelectric encoder based on digital potentiometer |
| CN112268633A (en) * | 2020-10-22 | 2021-01-26 | 合肥中科离子医学技术装备有限公司 | Temperature and resistance value conversion method for industrial platinum resistor with voltage of 30-73K |
| CN112461397A (en) * | 2020-11-26 | 2021-03-09 | 云南电网有限责任公司电力科学研究院 | Electronic thermometer for detecting field temperature of oil-immersed transformer |
| CN113459839A (en) * | 2021-07-23 | 2021-10-01 | 吉林省中赢高科技有限公司 | Method and device based on temperature compensation of direct-current charging seat |
| CN113557417A (en) * | 2019-03-01 | 2021-10-26 | 卡姆鲁普股份有限公司 | Utility meter including temperature sensor detection algorithm |
| CN113701905A (en) * | 2021-08-05 | 2021-11-26 | 歌联科技(苏州)有限公司 | High-precision temperature measuring method and device |
| CN114019443A (en) * | 2021-11-09 | 2022-02-08 | 南京能瑞自动化设备股份有限公司 | Temperature calibration method, device and system of electric energy meter |
| CN114720009A (en) * | 2022-06-09 | 2022-07-08 | 中国船舶重工集团公司第七0七研究所 | Digital high-precision temperature measurement system and method for relative gravimeter |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000241258A (en) * | 1999-02-25 | 2000-09-08 | T & D:Kk | Instrument and method for temperature measurement |
| CN101261163A (en) * | 2008-04-22 | 2008-09-10 | 上海电力学院 | Thermal resistor three-wire system, four wire system dual temperature measuring process |
| CN103063321A (en) * | 2012-12-28 | 2013-04-24 | 王坚 | Platinum resistance temperature measuring equipment and temperature measuring method thereof |
| CN104236742A (en) * | 2014-09-26 | 2014-12-24 | 江南大学 | Method and device for precisely measuring temperatures of platinum resistors |
| CN104458045A (en) * | 2014-12-09 | 2015-03-25 | 福建宁德核电有限公司 | Temperature measuring system |
| CN204881901U (en) * | 2015-07-12 | 2015-12-16 | 陈东 | High accuracy temperature sensor based on four -wire system PT100 |
| CN206161180U (en) * | 2016-11-08 | 2017-05-10 | 辽宁师范大学 | Wide -range high accuracy temperature measurement device based on platinum resistance |
-
2016
- 2016-11-08 CN CN201610978073.7A patent/CN106404207B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000241258A (en) * | 1999-02-25 | 2000-09-08 | T & D:Kk | Instrument and method for temperature measurement |
| CN101261163A (en) * | 2008-04-22 | 2008-09-10 | 上海电力学院 | Thermal resistor three-wire system, four wire system dual temperature measuring process |
| CN103063321A (en) * | 2012-12-28 | 2013-04-24 | 王坚 | Platinum resistance temperature measuring equipment and temperature measuring method thereof |
| CN104236742A (en) * | 2014-09-26 | 2014-12-24 | 江南大学 | Method and device for precisely measuring temperatures of platinum resistors |
| CN104458045A (en) * | 2014-12-09 | 2015-03-25 | 福建宁德核电有限公司 | Temperature measuring system |
| CN204881901U (en) * | 2015-07-12 | 2015-12-16 | 陈东 | High accuracy temperature sensor based on four -wire system PT100 |
| CN206161180U (en) * | 2016-11-08 | 2017-05-10 | 辽宁师范大学 | Wide -range high accuracy temperature measurement device based on platinum resistance |
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106989847A (en) * | 2017-03-22 | 2017-07-28 | 中国计量大学 | Error correcting method in system of Pt-resistance |
| CN106989847B (en) * | 2017-03-22 | 2019-09-06 | 中国计量大学 | Error correcting method in system of Pt-resistance |
| CN106989844A (en) * | 2017-04-26 | 2017-07-28 | 北京科技大学 | A kind of data acquisition equipment and acquisition method |
| CN107943180A (en) * | 2017-11-20 | 2018-04-20 | 中国电子科技集团公司第四十研究所 | A kind of circuit and method for suppressing reference circuit voltage drift |
| CN108037790A (en) * | 2017-11-30 | 2018-05-15 | 天津航空机电有限公司 | A kind of platinum resistance signal acquisition debug circuit based on double constant-current sources |
| CN111198591A (en) * | 2018-11-16 | 2020-05-26 | 纬湃科技投资(中国)有限公司 | Method for controlling current output of SDH8 circuit |
| CN113557417A (en) * | 2019-03-01 | 2021-10-26 | 卡姆鲁普股份有限公司 | Utility meter including temperature sensor detection algorithm |
| CN109991295A (en) * | 2019-04-29 | 2019-07-09 | 福建海纳欣生物科技有限公司 | A kind of intelligent pH combination electrode and its implementation with temperature drift self-regulation |
| CN109991295B (en) * | 2019-04-29 | 2023-12-08 | 福建海纳欣生物科技有限公司 | Intelligent pH composite electrode with temperature drift self-adjustment function and implementation method thereof |
| CN110632959A (en) * | 2019-10-18 | 2019-12-31 | 湖南晨威高科有限公司 | Charging pile internal temperature control method |
| CN111257641A (en) * | 2020-02-25 | 2020-06-09 | 东风电子科技股份有限公司 | Wide resistance range signal acquisition circuit and corresponding acquisition method |
| CN111257641B (en) * | 2020-02-25 | 2022-03-04 | 东风电子科技股份有限公司 | Wide resistance range signal acquisition circuit and corresponding acquisition method |
| CN111765913A (en) * | 2020-07-22 | 2020-10-13 | 中国科学院长春光学精密机械与物理研究所 | Absolute measuring ring photoelectric encoder based on digital potentiometer |
| CN111765913B (en) * | 2020-07-22 | 2021-07-06 | 中国科学院长春光学精密机械与物理研究所 | Absolute measuring ring photoelectric encoder based on digital potentiometer |
| CN112268633A (en) * | 2020-10-22 | 2021-01-26 | 合肥中科离子医学技术装备有限公司 | Temperature and resistance value conversion method for industrial platinum resistor with voltage of 30-73K |
| CN112461397A (en) * | 2020-11-26 | 2021-03-09 | 云南电网有限责任公司电力科学研究院 | Electronic thermometer for detecting field temperature of oil-immersed transformer |
| CN113459839A (en) * | 2021-07-23 | 2021-10-01 | 吉林省中赢高科技有限公司 | Method and device based on temperature compensation of direct-current charging seat |
| CN113459839B (en) * | 2021-07-23 | 2023-04-25 | 吉林省中赢高科技有限公司 | Method and device based on direct-current charging seat temperature compensation |
| CN113701905A (en) * | 2021-08-05 | 2021-11-26 | 歌联科技(苏州)有限公司 | High-precision temperature measuring method and device |
| CN114019443A (en) * | 2021-11-09 | 2022-02-08 | 南京能瑞自动化设备股份有限公司 | Temperature calibration method, device and system of electric energy meter |
| CN114720009A (en) * | 2022-06-09 | 2022-07-08 | 中国船舶重工集团公司第七0七研究所 | Digital high-precision temperature measurement system and method for relative gravimeter |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106404207B (en) | 2020-04-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106404207A (en) | Platinum resistance-based wide-range high-precision temperature measuring instrument and measuring method thereof | |
| CN103063321B (en) | Platinum resistance temperature measuring equipment and temperature measuring method thereof | |
| CN211528541U (en) | Resistance measuring circuit of programmable constant current source | |
| US5841077A (en) | Digital load cell assembly | |
| CN206161180U (en) | Wide -range high accuracy temperature measurement device based on platinum resistance | |
| CN105300269B (en) | A kind of wireless accurate strain gauge means and a kind of wireless accurate strain measurement method | |
| CN201672987U (en) | Temperature measuring apparatus | |
| CN200996875Y (en) | Multi-channel temperature-measuring recorder | |
| CN108204865A (en) | Industrial instrument, industrial control system and RTD temp measuring methods | |
| CN204314388U (en) | A kind of program controlled high precision resistance measuring instrument based on analog to digital converter | |
| CN203688096U (en) | Multirange medical temperature detecting instrument | |
| CN203534694U (en) | Remote-control digital weighing machine with temperature compensation function | |
| CN205176246U (en) | Conductivity meter self -calibration system | |
| CN113514168B (en) | Multi-channel temperature sensor testing device | |
| CN111693083B (en) | Online temperature and humidity instrument in-situ calibration method | |
| CN103234617A (en) | Remote-control digital weighing machine with temperature compensation function and temperature compensation method for remote-control digital weighing machine | |
| CN2043360U (en) | Multifunctional grain detector | |
| CN113310588A (en) | Remote temperature detection device based on mercury thermometer | |
| CN108766148B (en) | Program control potentiometer experimental instrument | |
| CN203535468U (en) | Detector for temperature and humidity controller | |
| CN220794379U (en) | Flow detection device for flow computer | |
| CN203069290U (en) | Platinum resistor temperature measuring equipment | |
| CN2591577Y (en) | Automatic correcting temperature and salinity sensor | |
| CN218726863U (en) | Low-cost two-wire system pH meter | |
| CN204902951U (en) | Digital capacitanc level meter based on TDC chip technology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20200403 Termination date: 20211108 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |