CN204128570U - A kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter - Google Patents

A kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter Download PDF

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Publication number
CN204128570U
CN204128570U CN201420537148.4U CN201420537148U CN204128570U CN 204128570 U CN204128570 U CN 204128570U CN 201420537148 U CN201420537148 U CN 201420537148U CN 204128570 U CN204128570 U CN 204128570U
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China
Prior art keywords
resistance
xtr101
chip
diode
potentiometer
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Expired - Fee Related
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CN201420537148.4U
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Chinese (zh)
Inventor
黄宋魏
葛鹏
于桂明
夏正一
童雄
和丽芳
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Kunming University of Science and Technology
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Kunming University of Science and Technology
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Abstract

The utility model relates to a kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter, belongs to measuring instrument field.The utility model comprises XTR101 chip, resistance R 1, diode D 1, thermopair, zero potentiometer RP 1, resistance R 2, adjust full potentiometer RP 2, resistance R 3, electric capacity C 1, electric capacity C 2, diode D 2, external power source, external loading, circuit board, connection terminal.The utility model saves the investment of thermocouple system compensating wire or extended line; Temperature signal is transmitted by 4-20mA direct current signal, has stronger antijamming capability than the compensating wire or connecting line transmitting faint thermoelectrical potential; Circuit board epoxy encapsulation is in stainless steel cylinder, and compact is compact, has waterproof and dustproof function; Transmitter box body adopt stainless steel material, resistance to mechanical clash into and resistance to corrosion strong; Transmitter and thermocouple sensor are that separate type is installed.

Description

A kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter
Technical field
The utility model relates to a kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter, belongs to measuring instrument field.
Background technology
In industrial site, often need thermocouple signal to amplify and the current signal nursing one's health into 4-20mA, to utilize for computer system.
Current Thermocouple Temperature Transmitter mainly contains cartridge and frame carried type:
Cartridge transmitter is mainly arranged in the terminal box of thermocouple sensor, the accessory in terminal box is needed to take out during installation, install cumbersome, and for the situation that site environment temperature is very high, serious drift is there is or easily damages in transmitter owing to being subject to high temperature action, in addition, require when cartridge transmitter is installed that thermocouple sensor must, with terminal box, not have the thermocouple sensor of terminal box then inapplicable for some.
Frame carried type transmitter can be arranged in switch board or field instrument case, need by compensating wire connecting sensor and transmitter, not only installation is inconvenient but also installation cost is higher, frame carried type transmitter waterproof, antidetonation, dust tightness, etch-proof poor-performing, faint thermocouple signal is easy to be subject to electromagnetic interference (EMI) in long range propagation process, brings difficulty to temperature detection.
Summary of the invention
The utility model provides a kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter, for overcoming the installation inconvenience that existing Thermocouple Temperature Transmitter exists, the situation needing compensating wire connection, be not suitable for hot environment, waterproof and corrosion resistance difference.
The technical solution of the utility model is: a kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter, comprises XTR101 chip 1, resistance R 12, diode D 13, thermopair 4, zero potentiometer RP 15, resistance R 26, full potentiometer RP is adjusted 27, resistance R 38, electric capacity C 19, electric capacity C 210, diode D 211, external power source 12, external loading 13, circuit board 17, connection terminal 18;
Described XTR101 chip 1, resistance R 12, diode D 13, zero potentiometer RP 15, resistance R 26, full potentiometer RP is adjusted 27, resistance R 38, electric capacity C 19, electric capacity C 210, diode D 211, external power source 12, external loading 13; Wherein the pin 5,6 of XTR101 chip 1 connects the full potentiometer RP of tune 27, zero potentiometer RP 1one end of 5 connects the pin 10 of XTR101 chip 1, zero potentiometer RP 1the other end of 5 connects diode D 13, resistance R 26, resistance R 38, diode D 1the anode of 3 and resistance R 1the pin 11 of XTR101 chip 1 is connected to, resistance R after 2 connections 1the other end of 2 and resistance R 2the pin 3 of XTR101 chip 1 is connected to, electric capacity C after the other end connection of 6 19 with resistance R 38 is in parallel, the pin 7 contact resistance R respectively of XTR101 chip 1 38, electric capacity C 2the negative electrode of 10, the negative electrode of external loading 13, the pin 8 of XTR101 chip 1 connects diode D 2the negative electrode of 11, diode D 2the other end of 11 connects electric capacity C 2the anode of 10 and the positive pole of external power source 12, the anode of external loading 13 is connected with the negative pole of external power source 12;
The both positive and negative polarity of described thermopair 4 connects the pin 10 and 4 of XTR101 chip 1 respectively;
Described circuit board 17 is designed to circle and two sides soldered elements, and connection terminal 18 is welded on circuit board 17, and connection terminal 18 has 4 terminals and connects the negative electrode of the both positive and negative polarity of thermopair 4, external power source 12 positive pole and external loading 13 respectively.
Described thermopair 4 is K type, J type, S type or R type.
Described zero potentiometer RP 1the maximum value of 5 is 100 Ω.
The full potentiometer RP of described tune 2the maximum value of 7 is 100 Ω.
The voltage range of described external power source 12 is 18-32VDC.
Principle of work of the present utility model is:
Thermopair 4 produces the mV voltage signal be directly proportional to temperature, and the positive pole of signal is directly connected to the pin 4 of XTR101 chip 1, and negative pole is by zero potentiometer RP 15 and resistance R 2be connected to the pin 3 of XTR101 chip 1 after 6, two 1mA constant current sources that circuit utilizes the pin 10 of XTR101 chip 1 and pin 11 to export, and utilize diode D 1the constant voltage effect of the PN junction of 3, by resistance R 12, resistance R 26, zero potentiometer RP 1the synergy of 5, the electric current exported when making temperature be measurement lower limit value is 4mA; The pin 5 of XTR101 chip 1 is connected with pin 6 adjusts full potentiometer RP 27, can conditioning signal gain, thus make temperature be that when measuring higher limit, circuit output current signal is 20mA; When the electric current of 2mA is by resistance R 3a stable voltage (about 5v) is produced, electric capacity C when 8 19 do filtering, diode D 211 burn out circuit, electric capacity C for preventing electric power polarity from connecing inverse time 210 filtering for outputing signal.
For different thermocouple sensors, because it exports mV voltage signal difference comparatively greatly, in order to make various sensor be taken into account, suitable resistance R can be chosen 12 and resistance R 26, and choose suitable zero potentiometer RP 15 potentiometer RPs full of tune 27, finally by adjustment zero potentiometer RP 15 potentiometer RPs full of tune 2the resistance value of 7, to adapt to different thermocouple sensors and different temperature measurement range.
The installation steps of circuit structure are as follows:
The bottom opening of Step1, described stainless steel cylinder 14 also welds internal thread screw rod 15, and the circular hole of internal thread screw rod 15 in the middle of circuit board 17 passes;
Step2, on division board 21, output 4 for installing the circular hole of connection terminal 18, the pin of connection terminal 18 is welded on circuit board 17 through after 4 circular holes; Output zero potentiometer hole 22 and adjust full potentiometer hole 23 to expose zero potentiometer RP 15 potentiometer RPs full of tune 2the rotating shaft of 7;
Be marked with epoxy filler 16 in Step3, stainless steel cylinder 14, circuit board 17 is arranged on stainless steel cylinder 14 together with division board 21 and connection terminal 18;
There is screw thread the upper end of Step4, stainless steel cylinder 14, can install threaded lid 19;
Step5, opening a circular hole in the appropriate location, upper end of stainless steel cylinder 14, crossing the end of a thread 20 for installing waterproof.
The beneficial effects of the utility model are:
1, save the investment of thermocouple system compensating wire or extended line, only need two plain conductors to power and signal output, this drops into for there being the occasion of numerous point for measuring temperature greatly can save wiring;
2, temperature signal is transmitted by 4-20mA direct current signal, has stronger antijamming capability than the compensating wire or connecting line transmitting faint thermoelectrical potential;
3, circuit board epoxy encapsulation is in stainless steel cylinder, and compact is compact, adapts to multiple production on-site environment, has waterproof and dustproof function;
4, transmitter box body adopt stainless steel material, resistance to mechanical clash into and resistance to corrosion strong;
5, transmitter and thermocouple sensor are that separate type is installed, and are conducive to the environment avoiding high temperature, humidity, severe corrosive, are convenient to be connected with computer control system, control instrument etc.
Accompanying drawing explanation
Fig. 1 is circuit theory diagrams of the present utility model;
Fig. 2 installs cut-away view in the utility model;
Fig. 3 is the installation vertical view not installing lid in the utility model;
In figure, each label is: 1-XTR101 chip, 2-resistance R 1, 3-diode D 1, 4-thermopair, 5-zero potentiometer RP 1, 6-resistance R 2, 7-adjusts full potentiometer RP 2, 8-resistance R 3, 9-electric capacity C 1, 10-electric capacity C 2, 11-diode D 2, 12-external power source, 13-external loading, 14-stainless steel cylinder, 15-internal thread screw rod, 16-epoxy filler, 17-circuit board, 18-connection terminal, 19-lid, 20-waterproof crosses the end of a thread, 21-division board, 22-zero potentiometer hole, and 23-adjusts full potentiometer hole.
Embodiment
Embodiment 1: as Figure 1-3, a kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter, comprises XTR101 chip 1, resistance R 12, diode D 13, thermopair 4, zero potentiometer RP 15, resistance R 26, full potentiometer RP is adjusted 27, resistance R 38, electric capacity C 19, electric capacity C 210, diode D 211, external power source 12, external loading 13, circuit board 17, connection terminal 18;
Described XTR101 chip 1, resistance R 12, diode D 13, zero potentiometer RP 15, resistance R 26, full potentiometer RP is adjusted 27, resistance R 38, electric capacity C 19, electric capacity C 210, diode D 211, external power source 12, external loading 13; Wherein the pin 5,6 of XTR101 chip 1 connects the full potentiometer RP of tune 27, zero potentiometer RP 1one end of 5 connects the pin 10 of XTR101 chip 1, zero potentiometer RP 1the other end of 5 connects diode D 13, resistance R 26, resistance R 38, diode D 1the anode of 3 and resistance R 1the pin 11 of XTR101 chip 1 is connected to, resistance R after 2 connections 1the other end of 2 and resistance R 2the pin 3 of XTR101 chip 1 is connected to, electric capacity C after the other end connection of 6 19 with resistance R 38 is in parallel, the pin 7 contact resistance R respectively of XTR101 chip 1 38, electric capacity C 2the negative electrode of 10, the negative electrode of external loading 13, the pin 8 of XTR101 chip 1 connects diode D 2the negative electrode of 11, diode D 2the other end of 11 connects electric capacity C 2the anode of 10 and the positive pole of external power source 12, the anode of external loading 13 is connected with the negative pole of external power source 12;
The both positive and negative polarity of described thermopair 4 connects the pin 10 and 4 of XTR101 chip 1 respectively;
Described circuit board 17 is designed to circle and two sides soldered elements, and connection terminal 18 is welded on circuit board 17, and connection terminal 18 has 4 terminals and connects the negative electrode of the both positive and negative polarity of thermopair 4, external power source 12 positive pole and external loading 13 respectively.
Described thermopair 4 is K type.
Described zero potentiometer RP 1the maximum value of 5 is 100 Ω.
The full potentiometer RP of described tune 2the maximum value of 7 is 100 Ω.
The voltage range of described external power source 12 is 18-32VDC.
The installation steps of circuit structure are as follows:
The bottom opening of Step1, described stainless steel cylinder 14 also welds internal thread screw rod 15, and the circular hole of internal thread screw rod 15 in the middle of circuit board 17 passes;
Step2, on division board 21, output 4 for installing the circular hole of connection terminal 18, the pin of connection terminal 18 is welded on circuit board 17 through after 4 circular holes; Output zero potentiometer hole 22 and adjust full potentiometer hole 23 to expose zero potentiometer RP 15 potentiometer RPs full of tune 2the rotating shaft of 7;
Be marked with epoxy filler 16 in Step3, stainless steel cylinder 14, circuit board 17 is arranged on stainless steel cylinder 14 together with division board 21 and connection terminal 18;
There is screw thread the upper end of Step4, stainless steel cylinder 14, can install threaded lid 19;
Step5, opening a circular hole in the appropriate location, upper end of stainless steel cylinder 14, crossing the end of a thread 20 for installing waterproof.
Design parameter design is as follows:
For the signal transmitting of K type thermopair, temperature measurement range is 0-800 DEG C, and supply voltage is 18-32VDC, and output current signal is 4-20mA, and external load resistors is less than 550 Ω.
In order to meet above-mentioned requirements, main element specifications and models of the present utility model are chosen as: the model of XTR101 chip 1 is SOL-16 encapsulation, resistance R 1the resistance of 2 is 2k Ω, diode D 1the model of 3 is 1N4001, zero potentiometer RP 1the setting value of 5 is 14.9 Ω, resistance R 2the resistance of 6 is 51 Ω, adjusts full potentiometer RP 2the setting value of 7 is 86 Ω, resistance R 3the resistance of 8 is 2.5k Ω, electric capacity C 19 is 0.01 μ, electric capacity C 210 is 0.01 μ, diode D 2the model of 11 is 1N4002, and the specification of stainless steel cylinder 14 is Φ 50x50, and the specification of internal thread screw rod 15 is M4X15, the diameter of circuit board 17 is Φ 38, the specification of connection terminal 18 is 3.81mm, and the specification that waterproof crosses the end of a thread 20 is M12*1.5, and the diameter of division board 21 is Φ 44.
Embodiment 2: as Figure 1-3, substantially the same manner as Example 1, difference is that described thermopair 4 is J type.
Design parameter design is as follows:
For the signal transmitting of J type thermopair, temperature measurement range is-100-100 DEG C, and supply voltage is 18-32VDC, and output current signal is 4-20mA, and external load resistors is less than 550 Ω.
For meeting above-mentioned requirements, main element specifications and models of the present utility model are chosen as: the model of XTR101 chip 1 is SOL-16 encapsulation, resistance R 1the resistance of 2 is 2k Ω, diode D 1the model of 3 is 1N4001, zero potentiometer RP 1the setting value of 5 is 19.53 Ω, resistance R 2the resistance of 6 is 51 Ω, adjusts full potentiometer RP 2the setting value of 7 is 24.98 Ω, resistance R 3the resistance of 8 is 2.5k Ω, electric capacity C 19 is 0.01 μ, electric capacity C 210 is 0.01 μ, diode D 2the model of 11 is 1N4002, and the specification of stainless steel cylinder 14 is Φ 50x50, and the specification of internal thread screw rod 15 is M4X15, the diameter of circuit board 17 is Φ 38, the specification of connection terminal 18 is 3.81mm, and the specification that waterproof crosses the end of a thread 20 is M12*1.5, and the diameter of division board 21 is Φ 44.
Embodiment 3: as Figure 1-3, substantially the same manner as Example 1, difference is that described thermopair 4 is S type.
Design parameter design is as follows:
For the signal transmitting of S type thermopair, temperature measurement range is 0-1200 DEG C, and supply voltage is 18-32VDC, and output current signal is 4-20mA, and external load resistors is less than 350 Ω.
For adapting to above-mentioned requirements, various main element specifications and models of the present utility model are chosen as: XTR101 chip 1 model is SOL-16 encapsulation, resistance R 1the resistance of 2 is 2k Ω, diode D 1the model of 3 is 1N4001, zero potentiometer RP 1the setting value of 5 is 14.9 Ω, resistance R 2the resistance of 6 is 51 Ω, adjusts full potentiometer RP 2the setting value of 7 is 128.3 Ω, resistance R 3the resistance of 8 is 2.5k Ω, electric capacity C 19 is 0.01 μ, electric capacity C 210 is 0.01 μ, diode D 2the model of 11 is 1N4002, and the specification of stainless steel cylinder 14 is Φ 50x45, and the specification of internal thread screw rod 15 is M4X15, the diameter of circuit board 17 is Φ 40, connection terminal 18 specification is 3.81mm, and it is M12*1.5 that waterproof crosses the end of a thread 20 specification, and division board 21 diameter is Φ 44.
Embodiment 4: as Figure 1-3, substantially the same manner as Example 1, difference is that described thermopair 4 is R type.
Design parameter design is as follows:
For the signal transmitting of R type thermopair, temperature measurement range is 300-1600 DEG C, and supply voltage is 18-32VDC, and output current signal is 4-20mA, and external load resistors is less than 350 Ω.
For adapting to above-mentioned requirements, main element specifications and models of the present utility model are chosen as: XTR101 chip 1 model is SOL-16 encapsulation, resistance R 1the resistance of 2 is 2k Ω, diode D 1the model of 3 is 1N4001, zero potentiometer RP 1the setting value of 5 is 12.5 Ω, resistance R 2the resistance of 6 is 51 Ω, adjusts full potentiometer RP 2the setting value of 7 is 41.81 Ω, resistance R 3the resistance of 8 is 2.5k Ω, electric capacity C 19 is 0.01 μ, electric capacity C 210 is 0.01 μ, diode D 2the model of 11 is 1N4002, and the specification of stainless steel cylinder 14 is Φ 50x45, and the specification of internal thread screw rod 15 is M4X15, the diameter of circuit board 17 is Φ 40, connection terminal 18 specification is 3.81mm, and it is M12*1.5 that waterproof crosses the end of a thread 20 specification, and division board 21 diameter is Φ 44.
By reference to the accompanying drawings embodiment of the present utility model is explained in detail above, but the utility model is not limited to above-mentioned embodiment, in the ken that those of ordinary skill in the art possess, various change can also be made under the prerequisite not departing from the utility model aim.

Claims (5)

1. a circuit structure for pocket two-wire system Thermocouple Temperature Transmitter, is characterized in that: comprise XTR101 chip (1), resistance R 1(2), diode D 1(3), thermopair (4), zero potentiometer RP 1(5), resistance R 2(6), full potentiometer RP is adjusted 2(7), resistance R 3(8), electric capacity C 1(9), electric capacity C 2(10), diode D 2(11), external power source (12), external loading (13), circuit board (17), connection terminal (18);
The pin 5,6 of described XTR101 chip (1) connects adjusts full potentiometer RP 2(7), zero potentiometer RP 1(5) one end connects the pin 10 of XTR101 chip (1), zero potentiometer RP 1(5) the other end connects diode D 1(3), resistance R 2(6), resistance R 3(8), diode D 1(3) anode and resistance R 1(2) pin 11 of XTR101 chip (1) is connected to after connecting, resistance R 1(2) the other end and resistance R 2(6) the other end is connected to the pin 3 of XTR101 chip (1) after connecting, electric capacity C 1(9) with resistance R 3(8) in parallel, the pin 7 contact resistance R respectively of XTR101 chip (1) 3(8), electric capacity C 2(10) negative electrode of negative electrode, external loading (13), the pin 8 of XTR101 chip (1) connects diode D 2(11) negative electrode, diode D 2(11) the other end connects electric capacity C 2(10) positive pole of anode and external power source (12), the anode of external loading (13) is connected with the negative pole of external power source (12);
The both positive and negative polarity of described thermopair (4) connects the pin 10 and 4 of XTR101 chip (1) respectively;
Described circuit board (17) is designed to circle and two sides soldered elements, connection terminal (18) is welded on circuit board (17), and connection terminal (18) has 4 terminals and connects the negative electrode of the both positive and negative polarity of thermopair (4), external power source (12) positive pole and external loading (13) respectively.
2. the circuit structure of pocket two-wire system Thermocouple Temperature Transmitter according to claim 1, is characterized in that: described thermopair (4) is K type, J type, S type or R type.
3. the circuit structure of pocket two-wire system Thermocouple Temperature Transmitter according to claim 1 and 2, is characterized in that: described zero potentiometer RP 1(5) maximum value is 100 Ω.
4. the circuit structure of pocket two-wire system Thermocouple Temperature Transmitter according to claim 1 and 2, is characterized in that: the full potentiometer RP of described tune 2(7) maximum value is 100 Ω.
5. the circuit structure of pocket two-wire system Thermocouple Temperature Transmitter according to claim 1 and 2, is characterized in that: the voltage range of described external power source (12) is 18-32VDC.
CN201420537148.4U 2014-09-18 2014-09-18 A kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter Expired - Fee Related CN204128570U (en)

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CN201420537148.4U CN204128570U (en) 2014-09-18 2014-09-18 A kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter

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Application Number Priority Date Filing Date Title
CN201420537148.4U CN204128570U (en) 2014-09-18 2014-09-18 A kind of circuit structure of pocket two-wire system Thermocouple Temperature Transmitter

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CN204128570U true CN204128570U (en) 2015-01-28

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104280052A (en) * 2014-09-18 2015-01-14 昆明理工大学 Circuit structure of compact type two-wire-system thermocouple transmitter and installing method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104280052A (en) * 2014-09-18 2015-01-14 昆明理工大学 Circuit structure of compact type two-wire-system thermocouple transmitter and installing method thereof
CN104280052B (en) * 2014-09-18 2017-06-13 昆明理工大学 A kind of circuit structure and its installation method of pocket two-wire system Thermocouple Temperature Transmitter

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CF01 Termination of patent right due to non-payment of annual fee
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Granted publication date: 20150128

Termination date: 20160918