CN102141448A - Method and device for measuring temperature of vibrating wire type device - Google Patents
Method and device for measuring temperature of vibrating wire type device Download PDFInfo
- Publication number
- CN102141448A CN102141448A CN 201010609944 CN201010609944A CN102141448A CN 102141448 A CN102141448 A CN 102141448A CN 201010609944 CN201010609944 CN 201010609944 CN 201010609944 A CN201010609944 A CN 201010609944A CN 102141448 A CN102141448 A CN 102141448A
- Authority
- CN
- China
- Prior art keywords
- temperature
- lead
- voltage
- resistance
- frequency measurement
- 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.)
- Pending
Links
Images
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
Abstract
The invention relates to a method and device for measuring temperature of a vibrating wire type device. The method comprises the following steps of: measuring a resistance value of a frequency measurement coil at certain moment, which is adopted when the vibrating wire type device is used for measuring frequency, through a four-wire resistance measurement method; and then obtaining a temperature value of the moment by utilizing resistance temperature characteristics of a frequency measurement coil so as to realize the temperature parameter measurement of the vibrating wire type device. The method for measuring the temperature of the vibrating wire type device improves the accuracy and the reliability of measuring the temperature of the vibrating wire type device.
Description
Technical field
The present invention relates to the thermometry and the device of the type vibration wire instrument in the safety monitoring instrument of health monitoring technical field, particularly a kind of Geotechnical Engineering of Geotechnical Engineering.
Background technology
In safety monitoring, adopt the physical quantitys such as ess-strain, temperature, seam aperture, seepage and distortion of safety monitoring instrument monitoring Geotechnical Engineerings such as type vibration wire (or claiming steel chord type) instrument usually, in order to the safety of analysis and judgement Geotechnical Engineering to Geotechnical Engineering.
Type vibration wire instrument (or claim vibrating string type sensor) by two ends fix, the string wire of homogeneous forms.String wire length is L, and in perception external influence power F (can be ess-strain, temperature, seam aperture, seepage and the distortion etc. of Geotechnical Engineering), string wire can produce the stretcher strain of Δ L, in elastic range, considers the influence of temperature T simultaneously,
Δ T=T-T wherein
0, α is a linear expansion coefficient, T
0, α, K be known constant number.The mechanical vibration natural frequency f of string wire can obtain by following formula:
Wherein E is the elastic modulus of string wire, ρ
vBe the density of string wire, λ is the Poisson's coefficient of string wire material, and these all are permanent numbers.Above-mentioned two formula are put in order, eliminated
This common variable, drawing F is definite function of f and T, just can realize the measurement of F by measurement f and T.Wherein, temperature parameters T is the measurement factor of a key.
The measuring method of traditional temperature parameters T normally is provided with thermistor in the type vibration wire instrument, thermistor can present different resistances with variation of temperature to responsive to temperature, obtains temperature parameters T by the resistance of measuring thermistor.Reality is, the resistance of thermistor is in operating temperature range, its theoretical maximum will reach 50K Ω, temperature detecting resistance value with respect to same widely used other type safety monitoring instrument in Geotechnical Engineering field such as differential resistance type sensor 120 Ω, exceed 1 more than the order of magnitude, consider from the resistance measurement precision, just need very high requirement be proposed to the insulativity of measuring system, even it is harsh to the degree that is difficult to Project Realization, if can't guarantee sufficiently high insulativity index, then can bring very big measuring error; Owing to the influence of the conductor resistance that is subjected in the type vibration wire instrument, drawing, also can make the resistance of measuring that error is arranged, simultaneously so the measuring accuracy of the temperature T that finally calculates and reliability decrease.And the safety monitoring of Geotechnical Engineering has very strict requirement to the reliability of safety monitoring instrument and the accuracy of measurement data, this just requires to make every effort to accurately and reliably on measuring principle and measuring method, so the type vibration wire instrument that use in the safety monitoring field adopts the said temperature measuring method can not satisfy Testing requirement.
Summary of the invention
There is measuring error in the temperature survey that the present invention is directed to existing type vibration wire instrument when adopting thermistor to carry out temperature sense, the problem that causes measuring accuracy and reliability decrease, a kind of thermometry of novel type vibration wire instrument is provided, and this method has improved accuracy and reliability that the type vibration wire instrument temperature is measured.The invention still further relates to a kind of temperature measuring equipment of type vibration wire instrument.
Technical scheme of the present invention is as follows:
A kind of thermometry of type vibration wire instrument, it is characterized in that, measure the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by the four-wire ohm mensuration, utilize the resistance-temperature characteristic of frequency measurement coil again, obtain the temperature value in the described moment, realize the parameter measurement of type vibration wire instrument temperature.
The resistance-temperature characteristic formula of described frequency measurement coil is R
t=R
0[1+ β * (T
t-T
0)]; Wherein, R
0And T
0Be respectively the initial resistivity value of frequency measurement coil and corresponding with it temperature value, R
tAnd T
tBe respectively the frequency measurement coil at t resistance value and corresponding with it temperature value constantly, β is the temperature-coefficient of electrical resistance of frequency measurement coil.
Described four-wire ohm mensuration is for to draw first current lead and the first voltage lead at one of them measuring junction of frequency measurement coil, draw second current lead and the second voltage lead at another measuring junction, described first current lead and second current lead are connected respectively to the constant current source two ends to constitute current return, the first voltage lead is passed to first pressure tap by first voltage follower, the second voltage lead is passed to second pressure tap by second voltage follower; Realize the measurement of the resistance value that the frequency measurement coil is carved at a time by measuring voltage between first pressure tap and second pressure tap.
The described first voltage lead connects lead by first successively and first voltage follower is passed to first pressure tap, and the second voltage lead connects lead by second successively and second voltage follower is passed to second pressure tap.
A kind of temperature measuring equipment of type vibration wire instrument, it is characterized in that, comprise interconnected electric resistance measuring apparatus and resistance temperature scaler, described electric resistance measuring apparatus is measured the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by the four-wire ohm mensuration, and exports this resistance value to the resistance temperature scaler; Described resistance temperature scaler utilizes the resistance-temperature characteristic of frequency measurement coil, obtains the temperature value in the described moment, realizes the parameter measurement of type vibration wire instrument temperature.
The resistance-temperature characteristic formula of the frequency measurement coil that described resistance temperature scaler utilizes is R
t=R
0[1+ β * (T
t-T
0)]; Wherein, R
0And T
0Be respectively the initial resistivity value of frequency measurement coil and corresponding with it temperature value, R
tAnd T
tBe respectively the frequency measurement coil at t resistance value and corresponding with it temperature value constantly, β is the temperature-coefficient of electrical resistance of frequency measurement coil.
Second current lead and the second voltage lead that described electric resistance measuring apparatus is included in first current lead that one of them measuring junction of frequency measurement coil draws and the first voltage lead and draws at another measuring junction, electric resistance measuring apparatus also comprises constant current source, first voltage follower, first pressure tap, second voltage follower, second pressure tap and voltage measurement treating apparatus, and the voltage measurement treating apparatus links to each other with the resistance temperature scaler; Described first current lead and second current lead are connected respectively to the constant current source two ends to constitute current return, the first voltage lead is passed to first pressure tap by first voltage follower, and the second voltage lead is passed to second pressure tap by second voltage follower; Measure the voltage between first pressure tap and second pressure tap and realize the measurement of the resistance value that the frequency measurement coil is carved at a time by the voltage measurement treating apparatus.
Described electric resistance measuring apparatus comprises that also the first connection lead is connected lead with second, described first connects lead is arranged between the first voltage lead and first voltage follower, and described second connects lead is arranged between the second voltage lead and second voltage follower.
Technique effect of the present invention is as follows:
The thermometry of the type vibration wire instrument that the present invention relates to, measure the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by the four-wire ohm mensuration, the method that adopts four-wire ohm to measure can be eliminated the influence of conductor resistance fully, obtain the true value that the frequency measurement coil is carved resistance at a time, because the frequency measurement coil has resistance-temperature characteristic, so thereby guarantee the measuring accuracy of the measuring accuracy assurance temperature parameter of resistance value.When having avoided the temperature survey of existing type vibration wire instrument to adopt thermistor to carry out temperature sense simultaneously because the insulativity variation is brought the problem of measuring error, this method of the present invention is utilized the resistance-temperature characteristic of the Primary Component frequency measurement coil of type vibration wire instrument when frequency measurement dexterously, when measuring, frequency parameter f realized the temperature T measurement function normal the realization, save production cost, reduced process procedure, promote the usefulness of device, the most important thing is to improve the reliability of type vibration wire instrument.
The temperature measuring equipment of the type vibration wire instrument that the present invention relates to, comprise interconnected electric resistance measuring apparatus and resistance temperature scaler, wherein, electric resistance measuring apparatus is measured the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by four-wire ohm mensuration pin-point accuracy ground, utilize the resistance-temperature characteristic of frequency measurement coil then by the resistance temperature scaler, obtain the temperature value in the described moment, realize that type vibration wire instrument temperature parameter T measures.The mode that more traditional thermistor carries out temperature sense can obtain more accurate, more stable measurement result, improved accuracy and reliability that the type vibration wire instrument temperature is measured, the safety monitoring that can satisfy Geotechnical Engineering is to the strict demand of the accuracy of the reliability of safety monitoring instrument and measurement data.
Description of drawings
Fig. 1 is the equivalent resistance circuit of type vibration wire instrument frequency slotted line circle.
Fig. 2 is a four-wire ohm mensuration schematic diagram.
Fig. 3 is the temperature measuring equipment structural representation of type vibration wire instrument of the present invention.
Fig. 4 is the temperature measuring equipment preferred structure synoptic diagram of type vibration wire instrument of the present invention.
Embodiment
The present invention will be described below in conjunction with accompanying drawing.
The measurand of the thermometry of type vibration wire instrument disclosed by the invention is the frequency measurement coil, and the frequency measurement coil is the Primary Component that the type vibration wire instrument is adopted when carrying out frequency measurement, and the frequency measurement coil has two measuring junctions usually.When carrying out temperature survey, the equivalence on electric of frequency measurement coil becomes a resistance R
tAs shown in Figure 1, this method adopts four-wire ohm mensuration survey frequency to measure the resistance value that coil is carved at a time earlier, its four-wire ohm is connected to draws two respectively at two measuring junction A, the B two ends of frequency measurement coil and draws lead, be shown in Figure 1ly to draw two at the A of frequency measurement coil measuring junction and draw lead A1 and A2, draw two at the B of frequency measurement coil measuring junction and draw lead B3 and B4.Four-wire ohm mensuration schematic diagram as shown in Figure 2, with each measuring junction of frequency measurement coil wherein one draw lead and be connected respectively to the constant current source two ends to constitute current return, be that A1 is first current lead, B4 is second current lead, A1, B4 connect constant current source I (or A1, B4 respectively by long lead 11 ', long lead 44 ' connection constant current source I), providing a numerical value by constant current source I is the DC current of I, by the first current lead A1, long lead 11 ', the second current lead B4, long lead 44 ' and Rt constitute current return; A2 is the first voltage lead, B3 is the second voltage lead, with the first voltage lead A2 by first connect lead 22 ', the first voltage follower A1 is passed to the first pressure tap O1, with the second voltage lead B3 by second connect lead 33 ', the second voltage follower A2 is passed to the second pressure tap O2, is about to R
tThe voltage at two ends respectively by the first voltage lead A2, first connect lead 22 ', voltage follower A1 and the second voltage lead B3, second connect lead 33 ', voltage follower A2 is delivered to O1, O2 end; Because the first voltage follower A1 and the second voltage follower A2 have empty short, empty disconnected characteristic, can the first voltage lead A2, first connect lead 22 ', the second voltage lead B3, second connect lead 33 ' on do not produce under the situation of electric current, R
tBoth end voltage is sent to 23 ends from A, B end, is ultimately delivered to O1O2 to 2 ' 3 ' end again and holds, and makes U simultaneously
O1o2=U
2 ' 3 '=U
23=U
ABSet up.According to the resistance measurement principle:
Because I is a known parameters, so by measuring U
O1O2Just can realize the resistance value R that the frequency measurement coil is carved at a time
tMeasurement.This mode can be eliminated the true value of the influence acquisition frequency measurement coil resistance of conductor resistance fully.
Utilize the resistance-temperature characteristic R=f (T) of type vibration wire instrument frequency slotted line circle, measuring the resistance value R that coil is carved at a time by four-wire ohm mensuration survey frequency
tAfter, according to R
t=f (T
t) funtcional relationship, inverse goes out t temperature value T constantly
t, realize the parameter measurement of type vibration wire instrument temperature.The initial resistivity value of supposing described frequency measurement coil is R
0Dui Ying temperature value is T with it
0, t resistance value constantly is R
t, Dui Ying temperature value is T with it
t, the temperature-coefficient of electrical resistance of frequency measurement coil method is β, then the resistance-temperature characteristic formula of frequency measurement coil is R
t=R
0[1+ β * (T
t-T
0)], wherein, R
0, T
0, β is known parameters.Formula is changed to:
Can be by R
tObtain T
t, realize the temperature survey function.
For example in the present embodiment, known parameters R
0=180.00 Ω, T
0=20.0 ℃, β=0.0040, electric current I=5mA now records voltage U
O1O2=1.000V, then
By formula:
The invention still further relates to a kind of temperature measuring equipment of type vibration wire instrument, its structural representation as shown in Figure 3, comprise interconnected electric resistance measuring apparatus and resistance temperature scaler, wherein, electric resistance measuring apparatus is measured the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by the four-wire ohm mensuration, and exports this resistance value to the resistance temperature scaler; The resistance temperature scaler receives the resistance value of electric resistance measuring apparatus transmission and utilizes the resistance-temperature characteristic of frequency measurement coil, obtains the temperature value in the described moment, realizes the parameter measurement of type vibration wire instrument temperature.
The temperature measuring equipment preferred structure synoptic diagram of Fig. 4 type vibration wire instrument.Electric resistance measuring apparatus is included in two that A, B two measuring junctions of frequency measurement coil draw respectively and draws lead, be second current lead and the second voltage lead that A measuring junction first current lead of drawing and the first voltage lead and B measuring junction are drawn, electric resistance measuring apparatus comprises that also constant current source, first connects lead, first voltage follower, the first pressure tap O1, the second connection lead, second voltage follower, the second pressure tap O2 and voltage measurement treating apparatus, and the voltage measurement treating apparatus links to each other with the resistance temperature scaler; First current lead and second current lead are connected respectively to the constant current source two ends to constitute current return, the first voltage lead that the A measuring junction of frequency measurement coil is drawn is passed to the first pressure tap O1 by the first connection lead, first voltage follower, and the second voltage lead that the B measuring junction of frequency measurement coil is drawn is passed to the second pressure tap O2 by the second connection lead, second voltage follower.Electric resistance measuring apparatus four-wire ohm mensuration carries out the frequency measurement coil resistance and measures, its schematic diagram as shown in Figure 2, first pressure tap O1 that the voltage measurement treating apparatus measures and the voltage between the second pressure tap O2 are frequency measurement coil both end voltage, and the current value that records according to constant current source is and flows through frequency measurement coil (equivalent resistance R again
t) electric current, voltage measurement treating apparatus directly computing obtains the resistance value that the frequency measurement coil is carved at a time.
The resistance value that the voltage measurement treating apparatus is carved the frequency measurement coil that obtains at a time is sent to the resistance temperature scaler, and the resistance temperature scaler utilizes the resistance-temperature characteristic formula R of frequency measurement coil
t=R
0[1+ β * (T
t-T
0)] (wherein, R
0And T
0Be respectively the initial resistivity value of frequency measurement coil and corresponding with it temperature value, R
tAnd T
tBe respectively the frequency measurement coil at t resistance value and corresponding with it temperature value constantly, β is the temperature-coefficient of electrical resistance of frequency measurement coil.R
0, T
0, β is known parameters), so R
tAnd T
tHave the function corresponding relation, can pass through R
tObtain the temperature value T in the described moment
t, realize the parameter measurement of type vibration wire instrument temperature.
Should be pointed out that the above embodiment can make those skilled in the art more fully understand the invention, but do not limit the present invention in any way creation.Therefore; although this instructions has been described in detail the invention with reference to drawings and Examples; but; those skilled in the art are to be understood that; still can make amendment or be equal to replacement the invention; in a word, all do not break away from the technical scheme and the improvement thereof of the spirit and scope of the invention, and it all should be encompassed in the middle of the protection domain of the invention patent.
Claims (8)
1. the thermometry of a type vibration wire instrument, it is characterized in that, measure the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by the four-wire ohm mensuration, utilize the resistance-temperature characteristic of frequency measurement coil again, obtain the temperature value in the described moment, realize the parameter measurement of type vibration wire instrument temperature.
2. thermometry according to claim 1 is characterized in that, the resistance-temperature characteristic formula of described frequency measurement coil is R
t=R
0[1+ β * (T
t-T
0)]; Wherein, R
0And T
0Be respectively the initial resistivity value of frequency measurement coil and corresponding with it temperature value, R
tAnd T
tBe respectively the frequency measurement coil at t resistance value and corresponding with it temperature value constantly, β is the temperature-coefficient of electrical resistance of frequency measurement coil.
3. thermometry according to claim 1 and 2, it is characterized in that, described four-wire ohm mensuration is for to draw first current lead and the first voltage lead at one of them measuring junction of frequency measurement coil, draw second current lead and the second voltage lead at another measuring junction, described first current lead and second current lead are connected respectively to the constant current source two ends to constitute current return, the first voltage lead is passed to first pressure tap by first voltage follower, the second voltage lead is passed to second pressure tap by second voltage follower; Realize the measurement of the resistance value that the frequency measurement coil is carved at a time by measuring voltage between first pressure tap and second pressure tap.
4. thermometry according to claim 3, it is characterized in that, the described first voltage lead connects lead by first successively and first voltage follower is passed to first pressure tap, and the second voltage lead connects lead by second successively and second voltage follower is passed to second pressure tap.
5. the temperature measuring equipment of a type vibration wire instrument, it is characterized in that, comprise interconnected electric resistance measuring apparatus and resistance temperature scaler, described electric resistance measuring apparatus is measured the resistance value that frequency measurement coil that the type vibration wire instrument adopts when the frequency measurement is carved at a time by the four-wire ohm mensuration, and exports this resistance value to the resistance temperature scaler; Described resistance temperature scaler utilizes the resistance-temperature characteristic of frequency measurement coil, obtains the temperature value in the described moment, realizes the parameter measurement of type vibration wire instrument temperature.
6. temperature measuring equipment according to claim 5 is characterized in that, the resistance-temperature characteristic formula of described frequency measurement coil is R
t=R
0[1+ β * (T
t-T
0)]; Wherein, R
0And T
0Be respectively the initial resistivity value of frequency measurement coil and corresponding with it temperature value, R
tAnd T
tBe respectively the frequency measurement coil at t resistance value and corresponding with it temperature value constantly, β is the temperature-coefficient of electrical resistance of frequency measurement coil.
7. according to claim 5 or 6 described temperature measuring equipments, it is characterized in that, second current lead and the second voltage lead that described electric resistance measuring apparatus is included in first current lead that one of them measuring junction of frequency measurement coil draws and the first voltage lead and draws at another measuring junction, electric resistance measuring apparatus also comprises constant current source, first voltage follower, first pressure tap, second voltage follower, second pressure tap and voltage measurement treating apparatus, and the voltage measurement treating apparatus links to each other with the resistance temperature scaler; Described first current lead and second current lead are connected respectively to the constant current source two ends to constitute current return, the first voltage lead is passed to first pressure tap by first voltage follower, and the second voltage lead is passed to second pressure tap by second voltage follower; Measure the voltage between first pressure tap and second pressure tap and realize the measurement of the resistance value that the frequency measurement coil is carved at a time by the voltage measurement treating apparatus.
8. temperature measuring equipment according to claim 7, it is characterized in that, described electric resistance measuring apparatus comprises that also the first connection lead is connected lead with second, described first connects lead is arranged between the first voltage lead and first voltage follower, and described second connects lead is arranged between the second voltage lead and second voltage follower.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010609944 CN102141448A (en) | 2010-12-28 | 2010-12-28 | Method and device for measuring temperature of vibrating wire type device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010609944 CN102141448A (en) | 2010-12-28 | 2010-12-28 | Method and device for measuring temperature of vibrating wire type device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102141448A true CN102141448A (en) | 2011-08-03 |
Family
ID=44409120
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201010609944 Pending CN102141448A (en) | 2010-12-28 | 2010-12-28 | Method and device for measuring temperature of vibrating wire type device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102141448A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105758548A (en) * | 2014-12-15 | 2016-07-13 | 中车大连电力牵引研发中心有限公司 | Temperature measurement circuit of platinum thermal resistor PT100 |
| CN106885640A (en) * | 2017-03-30 | 2017-06-23 | 苏州汇川联合动力系统有限公司 | A kind of motor temperature sample circuit |
| CN110132592A (en) * | 2019-04-16 | 2019-08-16 | 上海交通大学 | The effective prefastening load measurement method of assembly bearing |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201434686Y (en) * | 2009-07-10 | 2010-03-31 | 中国水利水电第三工程局有限公司 | One-to-two connection type vibrating wire transducer |
-
2010
- 2010-12-28 CN CN 201010609944 patent/CN102141448A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201434686Y (en) * | 2009-07-10 | 2010-03-31 | 中国水利水电第三工程局有限公司 | One-to-two connection type vibrating wire transducer |
Non-Patent Citations (2)
| Title |
|---|
| 《地层冻结工程技术和应用-中国地层冻结工程40年论文集》 19951231 姚直书、邓昕 钢筋计测量冻结井壁温度的试验研究及应用 第212页第1节至第214页倒数第4行 1-8 , * |
| 《山东电子》 19941231 顾正谊 探讨四线电阻在测量仪器中的应用 第2节 1-8 , 第01期 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105758548A (en) * | 2014-12-15 | 2016-07-13 | 中车大连电力牵引研发中心有限公司 | Temperature measurement circuit of platinum thermal resistor PT100 |
| CN106885640A (en) * | 2017-03-30 | 2017-06-23 | 苏州汇川联合动力系统有限公司 | A kind of motor temperature sample circuit |
| CN110132592A (en) * | 2019-04-16 | 2019-08-16 | 上海交通大学 | The effective prefastening load measurement method of assembly bearing |
| CN110132592B (en) * | 2019-04-16 | 2020-06-12 | 上海交通大学 | Method for measuring effective pre-tightening load of bearing for assembly |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104075841B (en) | aircraft engine pressure sensor detection circuit | |
| CN105579820B (en) | Pressure transmitter | |
| JP6042220B2 (en) | Inspection of measuring instrument system, corresponding measuring instrument system, and inspection system | |
| CN106018942A (en) | Current sensor array used for measuring three-phase current and measuring method thereof | |
| CN103235189A (en) | High-precision micro resistor measurement method based on double-current voltage ratio method and measurement system for realizing method | |
| CN102368086A (en) | Wheatstone bridge compensation resistance test method | |
| KR101179169B1 (en) | Temperature compensated load cell comprising strain gauges | |
| CN101936754B (en) | On-line self-correcting method of measuring data of dam safety monitoring automated data acquisition device | |
| CN102141448A (en) | Method and device for measuring temperature of vibrating wire type device | |
| CN108036804A (en) | A kind of device adjusted for resistance strain gage output | |
| CN202582775U (en) | Temperature measuring circuit | |
| CN107132417A (en) | A kind of precision resister measuring method of reactive circuit parameter drift | |
| CN104459330B (en) | High-voltage transmission line zero-sequence impedance measuring circuit and method | |
| CN201935749U (en) | Temperature measuring device of vibrating instrument | |
| CN207991561U (en) | A kind of device adjusted for resistance strain gage output | |
| Foord et al. | Transformer-ratio bridge network with precise lead compensation. And its application to the measurement of temperature and temperature difference | |
| CN102012279A (en) | Dual-constant current source temperature measurement system for thermal resistor | |
| CN206593749U (en) | A kind of field calibration system for magnetoelectric sensor | |
| CN201060231Y (en) | High accuracy electrical current detection and temperature on-line testing apparatus | |
| CN1011072B (en) | The electric apparatus temperature rise automatic detection device | |
| CN104457797B (en) | Method for determining a physical and/or chemical, temperature dependent, process variable | |
| CN102662098B (en) | High voltage, high-resistance method is measured with ratio stacked system | |
| CN204287327U (en) | A kind of ultra-high-tension power transmission line zero sequence impedance metering circuit | |
| CN104515600B (en) | Infrared sensor | |
| CN205067606U (en) | High tension transmission line impedance measuring circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20110803 |