Industrial-grade high-precision voltage type temperature transmitter system capable of automatic calibration

Abstract

The utility model discloses an industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration. The industrial-grade high-precision voltage-type temperature transmitter system comprises a temperature sensor unit, a temperature transmitting control unit, a voltage signal output unit and a voltage signal acquisition unit, the output end of the temperature sensor unit is connected with the temperature transmitting control unit; the voltage signal output unit comprises a voltage conversion circuit and a port protection circuit, the first end of the voltage conversion circuit is connected with the temperature transmitting control unit, the second end of the voltage conversion circuit is connected with the first end of the port protection circuit, and the second end of the port protection circuit is connected with the voltage output port; the first end of the voltage signal acquisition unit is connected with the second end of the voltage conversion circuit, and the second end of the voltage signal acquisition unit is connected with the temperature transmitting control unit.

Description

Technical Field

[0001] The present application relates to the field of industrial production technology, and in particular to an industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration. Background Art

[0002] Temperature transmitters are widely used in industrial control systems to convert temperature signals into standard electrical signal outputs.

[0003] The temperature transmitters on the market currently have the following common problems: First, there is a lack of effective isolation design between the power supply and signal ports, which are easily affected by external interference, causing the system to freeze or be damaged; second, the temperature signal acquisition unit mostly uses analog temperature measurement elements, the conversion circuit is complex, and errors are easy to occur, resulting in inaccurate output signals; third, the output accuracy of the voltage signal needs to be manually calibrated, and each device requires a lot of manpower and material resources in the production test link, affecting production efficiency.

[0004] Therefore, how to improve the measurement accuracy and calibration efficiency of the temperature transmitter system is an urgent problem to be solved. Utility Model Content

[0005] To this end, the present application provides an industrial-grade high-precision voltage-type temperature transmitter system that can be automatically calibrated to solve the problems of low measurement accuracy and calibration efficiency of the temperature transmitter system in the prior art.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions: an industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration, the system comprising

[0007] The system includes a temperature sensor unit, a temperature transmission control unit, a voltage signal output unit and a voltage signal acquisition unit;

[0008] The output end of the temperature sensor unit is connected to the temperature transmission control unit;

[0009] The voltage signal output unit includes a voltage conversion circuit and a port protection circuit, wherein a first end of the voltage conversion circuit is connected to the temperature transmission control unit, a second end of the voltage conversion circuit is connected to a first end of the port protection circuit, and a second end of the port protection circuit is connected to a voltage output port;

[0010] The first end of the voltage signal acquisition unit is connected to the second end of the voltage conversion circuit, and the second end of the voltage signal acquisition unit is connected to the temperature transmission control unit;

[0011] Among them, the temperature transmission control unit sends the temperature detection value output by the temperature sensor unit to the voltage conversion circuit; the voltage conversion circuit converts the temperature detection value into a corresponding voltage signal, and sends the voltage signal to the voltage signal acquisition unit and the port protection circuit respectively; the voltage signal acquisition unit sends the voltage signal to the temperature transmission control unit, and the temperature transmission control unit calibrates the voltage signal according to the voltage signal and the preset voltage signal; the port protection circuit is used to protect the voltage output port and output the voltage signal to the voltage output port.

[0012] Optionally, the temperature sensor unit includes a digital temperature sensor chip SHT45;

[0013] The digital temperature sensor chip SHT45 is connected to the temperature transmission control unit via an I2C communication interface.

[0014] Optionally, the temperature transmission control system includes a main control chip MCU;

[0015] The main control chip MCU adopts Saiyuan SC95F8617BP48R.

[0016] Optionally, the voltage conversion circuit includes a fourth chip U4, a third resistor R3 and a sixth resistor R6, and the fourth chip U4 is a chip SGM8273-2XS8GTR;

[0017] The 5th pin of the fourth chip U4 is divided into two paths, one path is connected to one end of the third resistor R3, and the other path is connected to one end of the sixth resistor R6; the 6th pin of the fourth chip U4 is connected to the 7th pin of the fourth chip U4, and the 7th pin of the fourth chip U4 is connected to the signal isolation circuit;

[0018] The other end of the third resistor R3 is the output end of the voltage conversion circuit, and the other end of the sixth resistor R6 is grounded.

[0019] Optionally, the port protection circuit includes a first diode TVS1 and a first resistor R1;

[0020] The positive electrode of the first diode TVS1 is grounded, and the negative electrode of the first diode TVS1 is connected to the output end of the voltage conversion circuit;

[0021] A first end of the first resistor R1 is connected to the cathode of the first diode TVS1 , and a second end of the first resistor R1 is connected to the voltage output port VO1 .

[0022] Optionally, the system further includes a signal isolation unit, and the signal isolation unit includes a chip 110E30;

[0023] The input end of the signal isolation unit is connected to the output end of the voltage conversion circuit.

[0024] Optionally, the input end of the voltage signal acquisition unit is connected to the output end of the signal isolation unit;

[0025] The voltage signal acquisition unit includes a tenth chip U10 and an eleventh chip U11;

[0026] The tenth chip U10 is SGM58031XMS, and the eleventh chip U11 is SGM4029-2.5XS8G.

[0027] Optionally, the system further includes a digital-to-analog converter, the digital-to-analog converter includes a sixth chip U6, and the sixth chip U6 is a chip GP8211S-TC5-EW.

[0028] Optionally, the system further comprises a power supply, wherein the power supply is a 24V AC power supply or a 24V DC power supply;

[0029] The power supply is connected to the temperature transmission control unit, the voltage conversion circuit, the port protection circuit and the voltage signal acquisition unit through a 24V to 24V power isolation circuit.

[0030] Compared with the prior art, this application has at least the following beneficial effects:

[0031] 1. The system adopts domestic chips, and the power supply and output signals are all isolated, which has high reliability and low cost.

[0032] 2. The use of digital temperature sensor chip and digital signal transmission ensures the reliable transmission of high-precision temperature acquisition signals.

[0033] 3. Automatic calibration of voltage signal output reduces manual involvement and improves production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly explain the prior art and the present invention, the following briefly introduces the drawings required for describing the prior art and the present invention. Obviously, the drawings described below are only exemplary, and for ordinary technicians in this field, other drawings can be derived from the provided drawings without creative work.

[0035] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which the present invention can be implemented. Any structural modification, change in proportion or adjustment of size should still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0036] Figure 1 This is a block diagram of the temperature sensor voltage signal output automatic calibration system provided by the utility model;

[0037] Figure 2 A block diagram of the sensor assembly provided by the utility model;

[0038] Figure 3 The temperature transmitter main control chip and peripheral circuit block diagram provided by the utility model;

[0039] Figure 4 The block diagram of the voltage signal output circuit provided by the utility model;

[0040] Figure 5 The block diagram of the voltage signal acquisition circuit provided by the utility model;

[0041] Figure 6 This is a block diagram of the system power supply provided by the utility model. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0043] In the description of the present invention, unless otherwise specified, "plurality" means two or more. The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are intended to distinguish the objects referred to. For schemes with a sequential flow, this terminology does not have to be understood as describing a specific order or sequence. For schemes with device structures, this terminology does not distinguish between importance, positional relationships, etc.

[0044] In addition, the terms "comprises", "has" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that have been explicitly listed, but may also include other steps or units that are not explicitly listed but are inherent to these processes, methods, products or apparatuses, or steps or units that are added based on further optimization schemes conceived by the present invention.

[0045] This embodiment provides an industrial-grade high-precision voltage-type temperature transmitter system that can be automatically calibrated, the system comprising a temperature sensor unit, a temperature transmission control unit, a voltage signal output unit, and a voltage signal acquisition unit;

[0046] The output end of the temperature sensor unit is connected to the temperature transmission control unit;

[0047] The voltage signal output unit includes a voltage conversion circuit and a port protection circuit, wherein a first end of the voltage conversion circuit is connected to the temperature transmission control unit, a second end of the voltage conversion circuit is connected to a first end of the port protection circuit, and a second end of the port protection circuit is connected to a voltage output port;

[0048] The first end of the voltage signal acquisition unit is connected to the second end of the voltage conversion circuit, and the second end of the voltage signal acquisition unit is connected to the temperature transmission control unit;

[0049] Among them, the temperature transmission control unit sends the temperature detection value output by the temperature sensor unit to the voltage conversion circuit; the voltage conversion circuit converts the temperature detection value into a corresponding voltage signal, and sends the voltage signal to the voltage signal acquisition unit and the port protection circuit respectively; the voltage signal acquisition unit sends the voltage signal to the temperature transmission control unit, and the temperature transmission control unit calibrates the voltage signal according to the voltage signal and the preset voltage signal. If the voltage signal collected by the signal acquisition unit is consistent with the preset voltage signal converted by the actual temperature sensor or is within the allowable deviation range, the voltage signal is not adjusted. If the collected voltage signal exceeds the preset deviation, the voltage signal is adjusted and corrected by the corresponding deviation value to ensure that the output voltage signal is within the allowable deviation range; the port protection circuit is used to protect the voltage output port and output the voltage signal to the voltage output port.

[0050] In this embodiment, the temperature sensor unit includes a digital temperature sensor chip SHT45;

[0051] The digital temperature sensor chip SHT45 is connected through I 2The C communication interface is connected to the temperature transmission control unit.

[0052] It should be noted that the temperature sensor unit includes a temperature sensor probe and leads. The temperature sensor probe uses a digital temperature sensor chip SHT45. The digital temperature sensor chip SHT45 and the main control chip MCU of the temperature transmitter control unit communicate through an I2C communication interface.

[0053] In this embodiment, since the temperature sensor chip SHT45 and the main control chip MCU transmit digital data, the conversion error of the temperature during the transmission process is avoided, and the output accuracy of the temperature sensor unit is well guaranteed.

[0054] In this embodiment, the temperature transmission control system includes a main control chip MCU;

[0055] The main control chip MCU adopts Saiyuan SC95F8617BP48R.

[0056] In this embodiment, the voltage conversion circuit includes a fourth chip U4, a third resistor R3 and a sixth resistor R6, and the fourth chip U4 is a chip SGM8273-2XS8GTR;

[0057] The 5th pin of the fourth chip U4 is divided into two paths, one path is connected to one end of the third resistor R3, and the other path is connected to one end of the sixth resistor R6; the 6th pin of the fourth chip U4 is connected to the 7th pin of the fourth chip U4, and the 7th pin of the fourth chip U4 is connected to the signal isolation circuit;

[0058] The other end of the third resistor R3 is the output end of the voltage conversion circuit, and the other end of the sixth resistor R6 is grounded.

[0059] The voltage conversion circuit is used to convert the output 0-10V voltage ratio into a signal that can be recognized by the signal acquisition circuit.

[0060] In this embodiment, the port protection circuit includes a first diode TVS1 and a first resistor R1;

[0061] The positive electrode of the first diode TVS1 is grounded, and the negative electrode of the first diode TVS1 is connected to the output end of the voltage conversion circuit; the port protection circuit is used to absorb external instantaneous high voltage, surge and other interference.

[0062] A first end of the first resistor R1 is connected to the cathode of the first diode TVS1 , and a second end of the first resistor R1 is connected to the voltage output port VO1 .

[0063] In this embodiment, the system further includes a signal isolation unit, and the signal isolation unit includes a chip 110E30;

[0064] The input end of the signal isolation unit is connected to the output end of the voltage conversion circuit.

[0065] In this embodiment, the input end of the voltage signal acquisition unit is connected to the output end of the signal isolation unit;

[0066] The voltage signal acquisition unit includes a tenth chip U10 and an eleventh chip U11;

[0067] The tenth chip U10 is SGM58031XMS, and the eleventh chip U11 is SGM4029-2.5XS8G.

[0068] The voltage divider resistors are configured as 4.99K and 2K, with a voltage divider ratio of 200 / 699, which convert the 0-10V signal into 0V-2.86V in proportion. The proportionally converted signal is conditioned by the emitter follower U4 and output to the signal isolation chip (VO_1). VO_1 is output to the ADC voltage signal acquisition chip through the isolation chip.

[0069] In this embodiment, the system further includes a digital-to-analog converter, and the digital-to-analog converter includes a sixth chip U6 , and the sixth chip U6 is a chip GP8211S-TC5-EW.

[0070] In this embodiment, the system further includes a power supply, and the power supply is a 24V AC power supply or a 24V DC power supply;

[0071] The power supply is connected to the temperature transmission control unit, the voltage conversion circuit, the port protection circuit and the voltage signal acquisition unit through a 24V to 24V power isolation circuit.

[0072] In one embodiment, Figure 1 The present invention mainly consists of four parts, including a temperature sensor unit, a temperature transmission control unit, a voltage signal output unit, and a voltage signal acquisition unit.

[0073] The temperature sensor assembly includes a temperature sensor probe and leads. The temperature sensor uses a digital chip and communicates with the MCU via I2C. Because the digital transmission between the MCU and the temperature sensor avoids the conversion error of the temperature during the transmission process, the output accuracy of the sensor is well guaranteed.

[0074] The temperature transmitter control unit, mainly the MCU, is responsible for transmitting the received temperature value to the digital-to-analog converter DAC chip and controlling the DAC chip to output the desired voltage signal.

[0075] The voltage signal output unit is where the DAC chip converts the temperature value transmitted from the MCU into a corresponding voltage signal, outputs it to the port, and uses a combination of a resistor and a TVS tube to protect the output port against surges and pulse groups.

[0076] The voltage signal acquisition unit accurately acquires the output voltage signal through a high-precision voltage acquisition circuit, outputs the acquired voltage signal to the ADC chip, and the ADC chip transmits the voltage signal to the MCU through the I2C digital interface.

[0077] The MCU compares the acquired voltage signal with the voltage signal to be output, detects whether the output voltage signal is within the accuracy range, and if it exceeds the accuracy requirement, self-tunes the output value.

[0078] Through the above process, for the actually output voltage signal, a closed-loop automatic calibration system is formed inside the control board. While the voltage signal is output externally, the system performs closed-loop acquisition, detection, and calibration on this output signal, ensuring the high-precision output of the voltage signal.

[0079] As Figure 2 shown, the temperature sensor component uses the digital temperature sensor chip SHT45 from MinYuan Electronics, is powered by DC 3.3V, and communicates through the I2C digital interface. In the temperature range of 0°C to 50°C, the temperature measurement accuracy deviation of the chip is ±0.1°C. Since it communicates with the MCU through the I2C digital interface, the intermediate signal transmission will not affect the accuracy of the chip.

[0080] As Figure 3 shown, the main control chip MCU uses the model SC95F8617BP48R from SAIYUAN, and is configured with corresponding power supply, crystal oscillator, and program debugging and downloading interface circuits, etc.; Three I2C ports of the MCU are respectively connected to the temperature sensor, the voltage output DAC chip, and the output voltage inspection chip to perform corresponding control and communication; A UART port test terminal is configured to display the acquired temperature value through a computer upper computer, and a test indicator is used to indicate the working state of the board.

[0081] As Figure 4 shown, the voltage signal conversion DAC uses the GP8211S chip from XianJi Electronics. The chip converts the temperature value input by the MCU into a corresponding voltage signal through the I2C interface and outputs it to the port. A 10R resistor and a TVS tube are configured to form a port surge protection circuit to improve the anti-interference ability of the system.

[0082] The acquisition circuit uses two high-precision resistors with 0.02% to form a voltage division circuit. After the operational amplifier, the signal VO_1 after the resistor voltage division is output to the signal isolation chip for the voltage signal acquisition circuit to acquire.

[0083] AsFigure 5 As shown, the voltage signal acquisition circuit acquires the isolated output VO_IN signal through the ADC chip. The ADC chip sends the acquired voltage signal to the MCU in real time via I2C3, so that the MCU can compare and calibrate the acquired output signal with the desired output voltage signal.

[0084] As Figure 6 shown, the system is powered by 24V AC or DC. The power supply passes through an isolation module that converts 24V AC to 24V DC, and provides the isolated DC 24V to power the entire system.

[0085] The above several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in some embodiments.

[0086] The technical features of the above embodiments can be combined arbitrarily (as long as there is no contradiction in the combination of these technical features). For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described; these embodiments that are not explicitly written out should also be considered to be within the scope described in this specification.

[0087] In the above text, the present utility model has been described in a relatively specific and detailed manner through general descriptions and specific embodiments. It should be noted that, without departing from the concept of the present utility model, it is obvious that several modifications and improvements can still be made to these specific embodiments, and these all belong to the protection scope of this application. Therefore, the protection scope of the patent of this application should be subject to the appended claims.

Claims

1. An industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration, characterized in that: The system includes a temperature sensor unit, a temperature transmission control unit, a voltage signal output unit and a voltage signal acquisition unit; The output end of the temperature sensor unit is connected to the temperature transmission control unit; The voltage signal output unit includes a voltage conversion circuit and a port protection circuit, wherein a first end of the voltage conversion circuit is connected to the temperature transmission control unit, a second end of the voltage conversion circuit is connected to a first end of the port protection circuit, and a second end of the port protection circuit is connected to a voltage output port; The first end of the voltage signal acquisition unit is connected to the second end of the voltage conversion circuit, and the second end of the voltage signal acquisition unit is connected to the temperature transmission control unit; Among them, the temperature transmission control unit sends the temperature detection value output by the temperature sensor unit to the voltage conversion circuit; the voltage conversion circuit converts the temperature detection value into a corresponding voltage signal, and sends the voltage signal to the voltage signal acquisition unit and the port protection circuit respectively; the voltage signal acquisition unit sends the voltage signal to the temperature transmission control unit, and the temperature transmission control unit calibrates the voltage signal according to the voltage signal and the preset voltage signal; the port protection circuit is used to protect the voltage output port and output the voltage signal to the voltage output port.

2. The industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration according to claim 1 is characterized in that: The temperature sensor unit includes a digital temperature sensor chip SHT45; The digital temperature sensor chip SHT45 is connected through I 2 The C communication interface is connected to the temperature transmission control unit.

3. The industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration according to claim 1 is characterized in that: The temperature transmission control system includes a main control chip MCU; The main control chip MCU adopts Saiyuan SC95F8617BP48R.

4. The automatically calibrated industrial-grade high-precision voltage-type temperature transmitter system according to claim 1, characterized in that: The voltage conversion circuit includes a fourth chip U4, a third resistor R3 and a sixth resistor R6, and the fourth chip U4 is a chip SGM8273-2XS8GTR; The 5th pin of the fourth chip U4 is divided into two paths, one path is connected to one end of the third resistor R3, and the other path is connected to one end of the sixth resistor R6; the 6th pin of the fourth chip U4 is connected to the 7th pin of the fourth chip U4, and the 7th pin of the fourth chip U4 is connected to the signal isolation circuit; The other end of the third resistor R3 is the output end of the voltage conversion circuit, and the other end of the sixth resistor R6 is grounded.

5. The industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration according to claim 1, characterized in that: The port protection circuit includes a first diode TVS1 and a first resistor R1; The positive electrode of the first diode TVS1 is grounded, and the negative electrode of the first diode TVS1 is connected to the output end of the voltage conversion circuit; A first end of the first resistor R1 is connected to the cathode of the first diode TVS1 , and a second end of the first resistor R1 is connected to the voltage output port VO1 .

6. The industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration according to claim 1, characterized in that: The system further includes a signal isolation unit, and the signal isolation unit includes a chip 110E30; The input end of the signal isolation unit is connected to the output end of the voltage conversion circuit.

7. The automatically calibrated industrial-grade high-precision voltage-type temperature transmitter system according to claim 6, characterized in that: The input end of the voltage signal acquisition unit is connected to the output end of the signal isolation unit; The voltage signal acquisition unit includes a tenth chip U10 and an eleventh chip U11; The tenth chip U10 is SGM58031XMS, and the eleventh chip U11 is SGM4029-2.5XS8G.

8. The industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration according to claim 1, characterized in that: The system further includes a digital-to-analog converter, which includes a sixth chip U6 , which is a chip GP8211S-TC5-EW.

9. The industrial-grade high-precision voltage-type temperature transmitter system capable of automatic calibration according to claim 1, characterized in that: The system also includes a power supply, which is a 24V AC power supply or a 24V DC power supply; The power supply is connected to the temperature transmission control unit, the voltage conversion circuit, the port protection circuit and the voltage signal acquisition unit through a 24V to 24V power isolation circuit.

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