Split type transformer oil temperature meter calibration device

Abstract

The utility model relates to a split type transformer oil temperature meter calibration device. The split type transformer oil temperature meter calibration device comprises a groove body unit and an electric measurement control unit. The electric measurement control unit is arranged on one side of the groove body unit and is electrically connected with the groove body unit; the groove body unit is used for providing a stable temperature source field for oil temperature meter calibration, and the electric measurement control unit is used for providing parameter measurement, data display and signal control functions for oil temperature meter calibration. The groove body unit and the electric measurement control unit are designed in a split mode and used in a combined mode, carrying is convenient, and on-site use is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature calibration, in particular to a split-type transformer oil temperature meter calibration device. Background Art

[0002] As the core equipment of the substation, the safe and reliable operation of the transformer directly determines the reliability and stability of the power supply. The oil temperature meter can monitor the changes in the transformer oil temperature so as to provide timely feedback and adjust the oil temperature. Therefore, the accuracy of the oil temperature meter directly determines the service life of the transformer. The traditional oil temperature meter calibration steps are relatively complicated and the calibration time is long, which is not conducive to the implementation of maintenance work and also reduces the safety of transformer operation. The laboratory calibration cycle is long and cannot meet the timeliness of the site. In particular, when on-site maintenance personnel need to quickly check and confirm the metering performance of the oil temperature meter, they urgently need an on-site calibration device that meets the requirements of relevant measurement specifications.

[0003] Currently, many manufacturers have developed portable dry body furnaces and portable liquid tanks. Some of their indicators meet the requirements of the transformer oil temperature meter measurement specification for standard instruments, but they still have problems such as large size, inconvenient to carry, narrow temperature control range, inability to increase or decrease temperatures at a constant speed, and lack of switch quantity detection function. Summary of the invention

[0004] Based on this, the purpose of the utility model is to provide a split transformer oil temperature gauge calibration device, which has the advantages of being easy to carry and use on site.

[0005] A split transformer oil temperature gauge calibration device includes a tank unit and an electric measurement control unit; the electric measurement control unit is arranged on one side of the tank unit and electrically connected thereto; the tank unit is used to provide a stable temperature source field for oil temperature gauge calibration, and the electric measurement control unit is used to provide parameter measurement, data display, and signal control functions for oil temperature gauge calibration. The tank unit and the electric measurement control unit are designed to be split and used in combination, which is convenient for transportation and on-site use.

[0006] Furthermore, the slot unit includes a first shell, a slot cavity, a standard device, a heating mechanism and a cooling mechanism; the slot cavity is fixedly arranged in the first shell, for containing a liquid medium; the standard device is inserted in the liquid medium; the heating mechanism is fixedly arranged in the slot cavity, for heating the liquid medium; the cooling mechanism is fixedly arranged on the outer periphery of the slot cavity, for cooling the liquid medium.

[0007] Furthermore, the tank unit also includes a stirring mechanism, which includes a stirring motor and a magnetic stirring bar, and the magnetic stirring bar is fixed on the output end of the stirring motor and located at the bottom of the tank cavity; when working, the stirring motor is started, and the magnetic stirring bar rotates to stir the liquid medium. Compared with the traditional blade stirring method, the magnetic stirring method adopted in this application has the advantages of small volume and low stirring heat.

[0008] Furthermore, the trough unit also includes a sample holder; the sample holder includes an upper support plate, a lower support plate, a connecting rod and a plurality of retaining springs, the upper support plate and the lower support plate are spaced apart and arranged in parallel, and are clamped at the upper end of the trough cavity; the upper support plate and the lower support plate are provided with a plurality of mutually corresponding through holes, and the through holes are used to insert the standard device or the oil temperature gauge that needs to be calibrated; the retaining spring is fixedly connected between the upper support plate and the lower support plate, located at the through hole, and is used to clamp the standard device or the oil temperature gauge that needs to be calibrated.

[0009] Furthermore, the tank unit further comprises a protective filter, which is clamped between the sample holder and the heating mechanism to prevent the lower end of the oil temperature gauge to be calibrated from touching the magnetic stirrer, causing it to lose step.

[0010] Furthermore, the tank unit also includes an overflow cup, which is fixed at the upper end of the tank cavity and is used to collect liquid medium overflowing from the tank cavity due to boiling due to heating or placing an oil temperature gauge that needs to be calibrated.

[0011] Furthermore, the slot unit also includes a cavity cover. When the calibration device is transported, the periphery of the cavity cover is sealed and connected to the inner wall of the upper end of the slot cavity.

[0012] Furthermore, the heating mechanism is the annular heating rod, which is fixed in the slot cavity; the cooling mechanism includes a semiconductor chip, a heat sink fin and a fan, the semiconductor chip is attached to the outer peripheral surface of the slot cavity, with its cold side facing the slot cavity, the heat sink fin is fixed to the hot side of the semiconductor chip, and the fan is fixed to the side of the heat sink fin away from the semiconductor chip for blowing air to dissipate heat; the first shell is provided with a heat dissipation port.

[0013] Furthermore, the electrical measurement control unit includes a second shell, an industrial computer, a switching power supply and a display screen; the industrial computer is fixedly mounted in the second shell and is electrically connected to the standard device, the oil temperature gauge to be calibrated, the heating mechanism and the refrigeration mechanism; the switching power supply and the display screen are fixedly mounted on the second shell and are connected to the industrial computer.

[0014] Furthermore, the industrial computer is provided with an oil temperature gauge calibration process, including a parameter setting module, a sensor self-calibration module, a temperature calibration module and a switch quantity calibration module; the parameter setting module is used to set stability, allowable deviation, stabilization time, dynamic value, dynamic initial value, dynamic cycle, temperature display resolution, and PID parameters; a temperature sensor is also provided in the slot cavity, and the temperature sensor is connected to the industrial computer. The sensor self-calibration module is used to calibrate the temperature sensor with a standard device to achieve high-accuracy output of the temperature sensor; the temperature calibration module is used to effectively control the heating and cooling of the liquid medium in the slot cavity; the switch quantity calibration module is used to read the indication of the standard thermometer and calculate the action error and switching error.

[0015] In order to better understand and implement the present invention, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of the split-type transformer oil temperature gauge calibration device of the present application;

[0017] Figure 2 It is a front view of the split transformer oil temperature gauge calibration device of the present application;

[0018] Figure 3 Three views of the sample holder of this application.

[0019] In the figure:

[0020] 1-tank unit; 11-first shell; 111-heat dissipation port; 12-tank cavity; 13-overflow cup; 14-sample holder; 141-upper support plate; 1411-first through hole; 1412-second through hole; 142-lower support plate; 143-connecting rod; 144-circlip; 15-standard device; 16-heating mechanism; 17-stirring mechanism; 171-stirring motor; 172-magnetic stirring bar; 18-protective filter; 19-refrigeration mechanism; 191-semiconductor chip; 192-heat dissipation fins; 193-fan;

[0021] 2-electrical measurement control unit; 21-second housing; 22-switching power supply; 23-display screen. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] In the description of the present invention, it should be noted that the terms "vertical direction", "upper", "lower", "horizontal" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, "first", "second", "third", and "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, or a connection through an intermediate medium, or the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] See also Figure 1 The present application provides a split-type transformer oil temperature gauge calibration device, including a tank unit 1 and an electric measurement control unit 2. The tank unit 1 is used to provide a stable temperature source field for the oil temperature gauge calibration device, and the electric measurement control unit 2 is used to provide parameter measurement, data display, signal control and other functions for the oil temperature gauge calibration device. The tank unit 1 and the electric measurement control unit 2 are connected by a cable.

[0026] The tank unit 1 includes a first shell 11 , a tank cavity 12 , an overflow cup 13 , a sample holder 14 , a standard device 15 , a heating mechanism 16 , a stirring mechanism 17 and a cooling mechanism 19 .

[0027] The groove cavity 12 is fixed in the first shell 11, and its upper end is open. In this embodiment, the groove cavity 12 is a cylindrical hollow body, and its upper end surface is flush with the upper end surface of the first shell 11. When working, the groove cavity 12 is filled with a liquid medium, which can be water, antifreeze or silicone oil. In this embodiment, dimethyl silicone oil with a viscosity of less than 50cs is used as the liquid medium.

[0028] The overflow cup 13 is covered at the opening of the tank cavity 12 and is used to collect the liquid medium overflowing from the tank cavity 12 due to heating and boiling or placing the object to be inspected.

[0029] The sample holder 14 is clamped inside the slot cavity 12 to support the standard device 15 and the object to be tested. In this embodiment, the standard device 15 is a temperature sensor for real-time monitoring of the temperature of the liquid medium in the slot cavity 12, and the object to be tested is an oil temperature gauge. In other embodiments, the standard device 15 is a second-class standard platinum resistor. Further, the sample holder 14 includes an upper support plate 141, a lower support plate 142, a connecting rod 143 and a plurality of retaining springs 144. The upper support plate 141 and the lower support plate 142 are spaced and arranged in parallel, the upper support plate 141 is fixed on the overflow cup 13, and the lower support plate 142 is located in the slot cavity 12. In this embodiment, the upper support plate 141 and the lower support plate 142 are both circular plates, and the upper support plate 141 and the lower support plate 142 are provided with a first through hole 1411 at the center of the circle, and the two first through holes 1411 are located on the same vertical line for inserting the standard device 15. A plurality of second through holes 1412 are provided on the upper support plate 141 and the lower support plate 142, and the second through holes 1412 of the upper support plate 141 and the second through holes 1412 of the lower support plate 142 correspond one to one and are located on the same vertical line for inserting the inspected object. Preferably, the second through holes 1412 of the upper support plate 141 and the second through holes 1412 of the lower support plate 142 are evenly distributed around their centers. In other embodiments, the upper support plate 141 and the lower support plate 142 are rectangular plates or plates of other shapes. A first through hole 1411 is provided at the geometric center of each of the upper support plate 141 and the lower support plate 142, and the two first through holes 1411 are located on the same vertical line. The two ends of the connecting rod 143 are respectively fixedly connected to the upper support plate 141 and the lower support plate 142. A plurality of retaining springs 144 are fixedly mounted on the upper support plate 141 and are located between the upper support plate 141 and the lower support plate 142. Preferably, one end of the retaining spring 144 is fixedly connected to the lower end surface of the upper support plate 141, and the other end thereof is tilted and located between two second through holes 1412 corresponding to each other on the upper support plate 141 and the lower support plate 142, for contacting the object to be tested. During operation, the standard 15 is sequentially passed through the first through holes 1411 of the upper support plate 141 and the lower support plate 142, and is clamped thereon; the object to be tested is sequentially inserted into the two second through holes 1412 corresponding to each other on the upper support plate 141 and the lower support plate 142, and the retaining spring 144 presses the object to be tested, so that it is clamped on the sample holder 14; the lower ends of the standard 15 and the object to be tested are both immersed in the liquid medium in the groove cavity 12, which is convenient for calibration.

[0030] Furthermore, the tank unit 1 further includes a cavity cover, which is generally cylindrical in shape, and the diameter of the cavity cover is the same as the diameter of the tank cavity 12. In order to prevent the liquid medium in the tank cavity 12 from spilling during transportation, the cavity cover can be clamped at the opening of the tank cavity 12, and the circumferential surface of the cavity cover is threadedly connected to the inner wall of the tank cavity 12 to achieve a sealing effect of the tank cavity 12.

[0031] The heating mechanism 16 includes an annular heating rod fixedly disposed in the tank cavity 12 and used for heating the liquid medium in the tank cavity 12 to reach a set temperature.

[0032] The stirring mechanism 17 includes a stirring motor 171 and a magnetic stirring bar 172. The stirring motor 171 is fixedly mounted in the first shell 11, located below the slot cavity 12, and its output end passes through the lower end surface of the slot cavity 12. The magnetic stirring bar 172 is fixedly mounted on the output end of the stirring motor 171, located at the bottom of the slot cavity 12, below the annular heating rod. During operation, the stirring motor 171 is started, and the magnetic stirring bar 172 rotates to stir the liquid medium in the slot cavity 12, so that the heat generated by the annular heating rod is evenly diffused. Compared with the traditional blade stirring method, the magnetic stirring method adopted in this application has the advantages of small size and low stirring heat.

[0033] Furthermore, the tank unit 1 also includes a protective filter 18, which is stuck in the tank cavity 12, between the annular heating rod and the sample holder 14, and is used to prevent the lower end of the object under test from touching the magnetic stirring bar 172, causing it to lose step. During use, the protective filter 18 can be moved down to the annular heating rod to form a heat conductor with the annular heating rod, increase the contact area between the heat of the annular heating rod and the liquid medium, and improve the heating efficiency. In this embodiment, the protective filter 18 is cylindrical.

[0034] The cooling mechanism 19 includes a semiconductor chip 191, a heat dissipation fin 192 and a fan 193. The semiconductor chip 191 is attached to the outer peripheral surface of the slot cavity 12, with the cold surface of the semiconductor chip 191 facing the slot cavity 12. The heat dissipation fin 192 is fixedly mounted on the side surface of the semiconductor chip 191 away from the slot cavity 12, that is, the hot side of the semiconductor chip 191, for heat dissipation. The upper end surface and side surface of the first shell 11 are provided with a heat dissipation port 111, and the fan 193 is fixedly mounted on the inner wall surface of the first shell 11 away from the slot cavity 12, for heat dissipation and transferring heat to the outside of the first shell 11.

[0035] The tank unit 1 further includes a temperature sensor, which is disposed in the tank cavity 12 and is used to monitor the temperature change of the liquid medium in the tank cavity 12 in real time.

[0036] The electrical measurement control unit 2 includes a second housing 21 , an industrial computer, a switching power supply 22 and a display screen 23 .

[0037] The second housing 21 is a rectangular housing with a hollow interior. The industrial computer is fixedly mounted in the second housing 21. The industrial computer is electrically connected to the standard device 15, the heating mechanism 16, the stirring mechanism 17, and the refrigeration mechanism 19, respectively. The industrial computer is provided with an oil temperature gauge calibration process for realizing the calibration of temperature parameters and switch quantities. The calibration process complies with the calibration specification of the oil temperature gauge. The oil temperature gauge calibration process includes a parameter setting module, a sensor self-calibration module, a temperature calibration module, and a switch quantity calibration module.

[0038] The parameter setting module is used to set stability, allowable deviation, stabilization time, dynamic value, dynamic initial value, dynamic cycle, temperature display resolution, PID parameters, and facilitates the subsequent experiment to call related parameters. The industrial computer accurately outputs the heating power and cooling power through the setting of the PID parameters, and realizes the precise control of the temperature of the liquid medium in the tank cavity 12.

[0039] When the temperature sensor is within the entire measuring range, the sensor self-calibration module is used to calibrate it with the standard 15 every 10°C. The calibrated data is saved in the database and corrected by linear fitting to achieve high-accuracy output of the temperature sensor. After calibration by the sensor self-calibration module, the output accuracy of the temperature sensor can reach ±0.05°C, which meets the technical requirements of the standard 15 in the technical specifications and can replace the original standard 15, solving the inconvenience of carrying a standard platinum resistance or a standard mercury thermometer for on-site calibration.

[0040] During operation, the object to be inspected, i.e., the oil temperature gauge, is inserted into the sample holder 14. The temperature calibration module is used to set the temperature to be calibrated, start the temperature control program, calculate according to the current temperature and predicted temperature of the liquid medium in the tank cavity 12, integrate the PID value, effectively control the heating and cooling of the liquid medium in the tank cavity 12, and realize the rapid rise and fall of the temperature. When the temperature reaches the target value and its stability meets the set threshold, it indicates that the current temperature of the liquid medium in the tank cavity 12 has stabilized, and the error of the oil temperature indication value can be calibrated.

[0041] The switch calibration module can calibrate up to four switches simultaneously. First, you need to set the instrument number, calibration temperature point and other parameters, then start the switch detection, adjust the contact pointer of the oil temperature gauge to the calibration temperature point Sv, and connect the contact to the signal circuit. When the temperature of the liquid medium in the tank cavity 12 is 5°C away from the calibration point temperature, slowly and evenly change the temperature of the liquid medium in the tank cavity 12 at a rate of (0.8~1.0)℃ / min, so that the contact produces a closed or open switching action. At the moment of action, read the standard thermometer indication, which is the contact upper travel switching value t S1 , or the lower travel switching value t S2 , the contact action error Δt can be calculated according to the formula d .

[0042] Simultaneously with the contact action error calibration, the travel switching value t at the same temperature point S1 , and the down stroke switching value t S2 The difference is the switching difference Δt q , the switching error Δt can be calculated according to the relevant formula q The action temperature, recovery temperature, action error, switching error, etc. during the switch calibration process can be automatically calculated by the software.

[0043] The switch power supply 22 and the display screen 23 are arranged on the first housing 11 and connected to the industrial computer. The first housing 11 is also provided with a switch quantity detection port for detecting the switch quantity of the oil temperature gauge; when the temperature of the oil temperature gauge is higher or lower than the set value, the switch quantity signal changes, and the change of this signal corresponds to the switch quantity calibration in the industrial computer. The first housing 11 is also provided with a low voltage signal (0-5V) and a low current (0-20mA) test port to facilitate the detection of the temperature transmitter signal; at the same time, a 24V power supply port is provided for powering the temperature secondary instrument or the temperature transmitter.

[0044] The split transformer oil temperature gauge calibration device of the present application has the following advantages:

[0045] (1) The tank unit 1 and the electrical measurement control unit 2 are designed as separate parts and can be used in combination, which is convenient for transportation and on-site use;

[0046] (2) A ring-shaped heating rod is arranged in the tank cavity 12, and a magnetic stirring method is adopted, and a protective filter screen 18 is arranged; a semiconductor sheet 191 is arranged outside the tank cavity 12 for cooling, and the metal conduction cold source is used as the overall realization of precise temperature control and adjustable temperature of the liquid medium in the tank cavity 12.

[0047] (3) The electrical measurement control unit 2 is provided with functions such as temperature calibration, switch quantity detection, and electrical signal detection, which can realize synchronous detection of multiple switch quantities and expand the calibration of temperature sensors and temperature transmitters;

[0048] (4) The industrial computer is equipped with a temperature calibration module and a switch calibration module to achieve rapid on-site calibration of the oil temperature gauge;

[0049] The tank unit 1 is provided with a high-precision temperature sensor, and the electrical measurement control unit 2 is provided with a sensor self-calibration module to achieve precise temperature measurement with an accuracy of up to ±0.05°C. During on-site calibration, it replaces the use of traditional standard thermometers.

[0050] The split transformer oil temperature meter calibration device of the present application can realize on-site calibration of the oil temperature meter temperature parameters and switch quantity, solving the problems of carrying too many devices, inconvenient transportation, poor resistance to environmental interference, low temperature control accuracy, and cumbersome data processing. The device also has the function of controllable heating and cooling rate and electrical signal detection, and can calibrate temperature sensors and temperature transmitters in industrial sites. After internal calibration, the high-precision temperature sensor built into the device can reach an accuracy of ±0.05℃, and can be used as a standard device 15 for calibrating industrial field temperature instruments.

[0051] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, and the utility model is also intended to include these modifications and modifications.

Claims

1. A split transformer oil temperature gauge calibration device, characterized in that: It includes a tank unit and an electrical measurement control unit; the electrical measurement control unit is arranged on one side of the tank unit and is electrically connected to the tank unit; the tank unit is used to provide a stable temperature source field for oil temperature gauge calibration, and the electrical measurement control unit is used to provide parameter measurement, data display, and signal control functions for oil temperature gauge calibration.

2. The split transformer oil temperature gauge calibration device according to claim 1 is characterized in that: The slot unit includes a first shell, a slot cavity, a standard device, a heating mechanism and a cooling mechanism; the slot cavity is fixedly arranged in the first shell and is used to contain a liquid medium; the standard device is inserted in the liquid medium; the heating mechanism is fixedly arranged in the slot cavity and is used to heat the liquid medium; the cooling mechanism is fixedly arranged on the outer periphery of the slot cavity and is used to cool the liquid medium.

3. The split transformer oil temperature meter calibration device according to claim 2 is characterized in that: The tank unit also includes a stirring mechanism, which includes a stirring motor and a magnetic stirring bar. The magnetic stirring bar is fixed on the output end of the stirring motor and located at the bottom of the tank cavity. When working, the stirring motor is started and the magnetic stirring bar rotates to stir the liquid medium.

4. The split transformer oil temperature gauge calibration device according to claim 3 is characterized in that: The trough unit also includes a sample holder; the sample holder includes an upper support plate, a lower support plate, a connecting rod and a plurality of retaining springs, the upper support plate and the lower support plate are spaced apart and arranged in parallel, and are clamped at the upper end of the trough cavity; the upper support plate and the lower support plate are provided with a plurality of mutually corresponding through holes, and the through holes are used to insert the standard device or the oil temperature gauge that needs to be calibrated; the retaining spring is fixedly connected between the upper support plate and the lower support plate, located at the through hole, and is used to clamp the standard device or the oil temperature gauge that needs to be calibrated.

5. The split transformer oil temperature gauge calibration device according to claim 4 is characterized in that: The tank unit further comprises a protective filter, and the protective filter is clamped between the sample holder and the heating mechanism.

6. The split transformer oil temperature gauge calibration device according to claim 5 is characterized in that: The tank unit also includes an overflow cup, which is fixed at the upper end of the tank cavity and is used to collect liquid medium overflowing from the tank cavity due to boiling or placing an oil temperature gauge that needs to be calibrated.

7. The split transformer oil temperature gauge calibration device according to claim 6 is characterized in that: The slot unit also includes a cavity cover. When the calibration device is transported, the periphery of the cavity cover is sealed and connected to the inner wall of the upper end of the slot cavity.

8. The split transformer oil temperature meter calibration device according to claim 2 is characterized in that: The heating mechanism is a ring-shaped heating rod, which is fixed in the slot cavity; the cooling mechanism includes a semiconductor chip, a heat dissipation fin and a fan. The semiconductor chip is attached to the outer peripheral surface of the slot cavity with its cold side facing the slot cavity, the heat dissipation fin is fixed to the hot side of the semiconductor chip, and the fan is fixed to the side of the heat dissipation fin away from the semiconductor chip for blowing air to dissipate heat; a heat dissipation port is provided on the first shell.

9. The split transformer oil temperature gauge calibration device according to claim 2, characterized in that: The electrical measurement control unit includes a second shell, an industrial computer, a switching power supply and a display screen; the industrial computer is fixedly arranged in the second shell and is electrically connected to the standard instrument, the oil temperature gauge to be calibrated, the heating mechanism and the refrigeration mechanism; the switching power supply and the display screen are fixedly arranged on the second shell and are connected to the industrial computer.

10. The split transformer oil temperature gauge calibration device according to claim 9, characterized in that: The industrial computer is provided with an oil temperature gauge calibration process, including a parameter setting module, a sensor self-calibration module, a temperature calibration module and a switch calibration module; the parameter setting module is used to set stability, allowable deviation, stabilization time, dynamic value, dynamic initial value, dynamic cycle, temperature display resolution, and PID parameters; the tank cavity is also provided with a temperature sensor, the temperature sensor is connected to the industrial computer, and the sensor self-calibration module is used to calibrate the temperature sensor with a standard device to achieve high-accuracy output of the temperature sensor; The temperature calibration module is used to effectively control the heating and cooling of the liquid medium in the tank cavity; the switch quantity calibration module is used to read the indication of the standard thermometer and calculate the action error and the switching error.

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